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13C NMR Spectra of pentacyclic triterpenoids—a compilation and some salient features
Abstract
A compilation of the13C NMR data of a selected variety of naturally occurring pentacyclic triterpenoids, arranged skeletonwise, is provided. A bri
... The IR absorption revealed the presence of a O-H (3447 cm −1 ), C-H (2931 cm −1 ), carbonyl (1692 cm −1 ), C = C (1523 cm −1 ), and C-O (1034 cm −1 ) functionalities (figure S2). The 1 H NMR data (Tables S1) indicated six methyl groups at δ Η 1.05 (H 3 -23), 0.95 (H 3 -30), 0.92 (H 3 -25), 0.90 (H 3 -29), 0.84 (H 3 -24), and 0.77 (H 3 -26); one oxymethylene at δ Η 3.74 (1H, d, J = 12.0) & 3.47 (1H, d, J = 12.5); an oxymethine proton at δ Η 3.16, one olefinic proton at δ Η 5.61 (t, J = 2.5 Hz, H-12); in addition to ten methylene and three methine proton resonances ascribed to olean-12-en-28-oic acid skeleton (Mahato and Kundu 1994). Furthermore, the 1 H NMR spectrum displayed signals between δ Η 3.18 − 3.84 and an anomeric proton at δ Η 4.31 (d, J = 8.0 Hz, Glc-H-1) assigned to a D-glucose moiety. ...
... A closer look at the chemical shifts of C-12 and C-13, δ C 129.9 and 139.7 respectively in compounds 1-4, compare to 123.4 and 145.1 in compound 5, suggests that hydroxylation of C-27 leads to an up-field shift of C-12 of about 5.7 ppm and a corresponding downfield shift of C-13 of about 5.3 ppm. Further inside into structure confirms C-18 carbon in all compounds to be β-oriented with a chemical shift around δ 42.2 (Mahato and Kundu 1994). ...
Tetrapleura tetraptera fruit, used as spice in West Africa was studied chemically; five previously undescribed triterpenoid saponins 1 - 5 and four known compounds 6-9 were isolated from the n-Butanol fraction. The chemical structures of all nine isolates were determined by comprehensive analysis of HRMS, 1D & 2D NMR experiments and by comparison with data in the literature. All nine compounds were evaluated for antibacterial activity by the broth microdilution through the rapid p-iodonitrotetrazolium chloride (INT) colorimetric technique. The results showed that only compounds 5 (MIC = 64 µg/mL against P. aeruginosa and P. stuartii) and 8 (MIC = 64 µg/mL against E. coli) exhibited moderate antibacterial activity. The rest of the compounds displayed weak antibacterial activity against the tested organisms. Molecular docking studies was used to comprehend antibacterial activities.
... Further analysis on HMQC and HMBC spectral data elucidated that five of the non-protonated carbon atoms showed at C 145.0, 143.6, 126.6 and 140.4 and two protonated carbon atoms at C 110.8 and 111.5 to be aromatic. Compound Table 4) and the direct comparison of literature data revealed the structure of the compound as 3β-OAc, 28-COOH and acetyl aleuritolic acid (14). ...
... It is reported that diterpenoid compound (1), podocarpane-type diterpenes rarely occur in nature had been previously isolated from Taiwania cryptomerioides (5). Also, compound 2 was reported from Maprounea guianensis, the plant that is well known to produce triterpenes with cytotoxic activity (14). Further, it is stated that compound 2 showed anticancer properties, significantly inhibiting tumor cell growth. ...
We did a preliminary investigation of the allelopathic activity of 60 invasive and medicinal plants in Sri Lanka on Lactuca sativa (lettuce) and Raphanus sativus (radish). Out of 60 plants, 14 significantly reduced lettuce seedling lengths than distilled water, and 55 plants reduced radish seedling growth. In consideration of all the parameters tested, Cardiospermum halicacabum and Canarium zeylanicum Blume showed the highest phytotoxicity. C. zeylanicum (family Burseraceae), an endemic plant in Sri Lanka was selected for the isolation of phytotoxic compounds. The whole tree has a distinct fragrance bears edible seeds and has potential health benefits. This plant is used for medicinal purposes and its bark contains 3-hydroxy-12-methoxy-8,11,13-podocarpatrien-3-one and acetyl aleuritolic acid. This is the first report of the aforementioned two compounds from C. zeylanicum. These compounds exhibited phytotoxicity against lettuce.
... The 1 H and 13 C NMR spectra showed the signals attributable to one double bond (δ H 5.27 (1H, t, J = 3.5 Hz, C-24)). Considering the features revealed by the 1 H and 13 C NMR spectra, this compound likely belonged to the family of ursane triterpenes [29]. It was found that the overall 1 H and 13 C NMR spectral data of 1 ( Figure S17, Table S1) displayed a high degree of resemblance to those of the ursane-type triterpene ursolic acid [19]. ...
... In the 1 H and 13 Table S2) indicated this compound was a oleane-type triterpene [29]. Finally, compound 2 was identified as 24-acetoxy-3αhydroxyolean-12-en-28-oic, on the basis of comparable data in the published work [20,21]. ...
An investigation of the potential ornamental plant Ophiorrhiza chinensis H.S. Lo (Rubiaceae) was conducted, which resulted in the discovery of eight structurally diverse compounds, including two triterpenes, two steroids, two anthraquinones, one alkaloid, and one coumarin. These chemical constituents were isolated by repeated column chromatography and identified by analysis of their NMR spectral data. All of these substances were found in this species for the first time, and four of them were first isolated from the genus Ophiorrhiza. The chemotaxonomic importance of these isolates was discussed, indicating four chemotaxonomic markers for O. chinensis. The tyrosinase inhibitory activity of these isolates was evaluated by a colorimetric method. As a result, six phytochemicals demonstrated moderate tyrosinase inhibitory effects with IC50 values ranging from 25.7 μM to 68.1 μM. Moreover, the binding modes between the active compounds and the mushroom tyrosinase were analyzed preliminarily assisted by molecular docking calculations. This study filled up the knowledge gap of the unreported phytochemical and pharmacological profiles of secondary metabolites from the species O. chinensis.
... The known compounds were identified from their respective 13 C NMR data, compared with data from the literature, as friedelan-3-one (2), 14 friedelan-3β-ol (3), 16 friedelane-3,15dione (4), 13 15α-hydroxyfriedelan-3-one (5), 13 28-hydroxyfriedelan-3-one (6), 17 30-hydroxyfriedelan-3-one (7) 18 and 29hydroxyfriedelan-3-one (8). 16 Antiviral Assay. ...
... The known compounds were identified from their respective 13 C NMR data, compared with data from the literature, as friedelan-3-one (2), 14 friedelan-3β-ol (3), 16 friedelane-3,15dione (4), 13 15α-hydroxyfriedelan-3-one (5), 13 28-hydroxyfriedelan-3-one (6), 17 30-hydroxyfriedelan-3-one (7) 18 and 29hydroxyfriedelan-3-one (8). 16 Antiviral Assay. The antiviral activity of compounds 1−8 and the hexane (EH), chloroform (EC) and ethyl acetate (EAE) extracts was evaluated against the murine coronavirus MHV-3 (Table 2). ...
Salacia grandifolia is naturally found in the Atlantic Forest regions of Brazil. Despite the pharmacological potential of plants from the Salacia genus, phytochemical studies on this species have not been reported in literature. A new triterpene, 28-hydroxyfriedelane-3,15-dione (1), and seven known compounds (friedelan-3-one (2), friedelan-3β-ol (3), friedelane-3,15-dione (4), 15α-hydroxyfriedelan-3-one (5), 28-hydroxyfriedelan-3-one (6), 30-hydroxyfriedelan-3-one (7), and 29-hydroxyfriedelan-3-one (8)) were obtained from the hexane extract of Salacia grandifolia leaves. These isolated compounds and three extracts, hexane (EH), chloroform (EC), and ethyl acetate (EAE), were assessed for their potential biological activities, which consisted in the evaluation of antiviral activity against a murine coronavirus, mouse hepatitis virus 3 (MHV-3), antibacterial activity against the susceptible and methicillin-resistant Staphylococcus aureus (MRSA), and antileukemia activity against the THP-1 and K-562 cell lines. The extracts EH and EAE along with the triterpenes 1 and 6 exhibited moderate to high antiviral activity, with emphasis on 6, which presented an EC50 value of 2.9 ± 0.3 μM. None of the compounds presented antibacterial activity against the tested strains. The evaluated compounds 1, 4, 6 and 7 exhibited low cytotoxic activity against the tested leukemia cell lines. Taken together, this study comprises an overview for the potential of the Salacia grandifolia biological activities, including a new isolated triterpene.
... The methanolic extract obtained from the stem bark of G. sylvestre extraction was fractionated over SiO 2 gel CC and further purified using repeated CC to yield 12 known compounds (1-12). The structures of all the isolated compounds were achieved using their 1D-& 2D-NMR, MS, IR spectra analyses and with comparison of their data to reported literature as: a mixture of stigmasterol and spinasterol (1 and 2), then (3β, 24 S) stigmata-5,25-dien-3-ol or clerosterol (3) [32], 20S-hydroxy-4,6,24(28)-ergostatrien-3-one (4) [33], 3β-hydroxyolean-12-ene or β-amyrine (5) [34], oleanolic acid (6) [35], bellericagenine B (7) [34], betulin (8) [36], betulinic acid (9) [36], 5-hydroxy-6,7,3′,4′-tetramethoxyflavone or belamcanidine (10) [37], velutin or 3′, 7-dimethoxy-4′,5-dihydroxyflavone (11) [38], and cirsilineol or 5, 4′-dihydroxy-6,7,3′-trimethoxyflavone (12) [37] (Fig. 1). ...
... The methanolic extract obtained from the stem bark of G. sylvestre extraction was fractionated over SiO 2 gel CC and further purified using repeated CC to yield 12 known compounds (1-12). The structures of all the isolated compounds were achieved using their 1D-& 2D-NMR, MS, IR spectra analyses and with comparison of their data to reported literature as: a mixture of stigmasterol and spinasterol (1 and 2), then (3β, 24 S) stigmata-5,25-dien-3-ol or clerosterol (3) [32], 20S-hydroxy-4,6,24(28)-ergostatrien-3-one (4) [33], 3β-hydroxyolean-12-ene or β-amyrine (5) [34], oleanolic acid (6) [35], bellericagenine B (7) [34], betulin (8) [36], betulinic acid (9) [36], 5-hydroxy-6,7,3′,4′-tetramethoxyflavone or belamcanidine (10) [37], velutin or 3′, 7-dimethoxy-4′,5-dihydroxyflavone (11) [38], and cirsilineol or 5, 4′-dihydroxy-6,7,3′-trimethoxyflavone (12) [37] (Fig. 1). ...
This study investigated the chemical constituents, antioxidant potential, and in vitro and in silico antidiabetic activity of Gymnema sylvestre. Column chromatography and spectroscopic techniques identified twelve compounds from the methanol extract, including 4 sterols (1–4), 5 triterpenoids (5–9), and 3 flavonoids (10–12). The chemophenetic significance of all compounds was also investigated. The antioxidant capacity of the extract and compounds (1–4) was evaluated using FRAP and DPPH assays. The extract exhibited strong free radical scavenging activity (IC50 = 48.34 µg/mL), while compounds (1–4) displayed varying degrees of efficacy (IC50 = 98.30–286.13 µg/mL). The FRAP assay indicated significant reducing power for both extract and compounds (58.54, 47.61, 56.61, and 49.11 mg Eq.VitC/g for extract and compounds 1 & 2, 3, and 4, respectively). The antidiabetic potential was assessed through α-amylase and α-glucosidase enzyme inhibition assays. The crude extract demonstrated the most potent inhibition (IC50 = 218.46 and 57.42 µg/mL for α-glucosidase and α-amylase respectively) suggesting its potential for managing postprandial hyperglycaemia. In silico studies employed molecular docking and dynamics simulations to elucidate the interactions between identified compounds and α-amylase/α-glucosidase enzymes. The results revealed promising binding affinities between the compounds and target enzymes, with compound 6 demonstrating the highest predicted inhibitory activity with −10 kcal/mol and −9.1 kcal/mol for α-amylase and α-glucosidase, respectively. This study highlights the presence of diverse bioactive compounds in Gymnema sylvestre. The extract exhibits antioxidant properties and inhibits carbohydrate-digesting enzymes, suggesting its potential as a complementary therapeutic approach for managing hyperglycaemia associated with type 2 diabetes.
... They were conrmed from their proton and carbon chemical shi values (Fig. S1-S8 †) compared with those reported in the literature. They were identied as 24-b-ethylcholesta-5(6),22(23),25(26)-triene-3-ol (1) and its glucoside 24-b-ethyl-cholesta-5(6),22 (23),25(26)-triene-3-O-b-D-glucoside (4), 20 besides a-amyrin (2), 21,22 and linoleic acid (3). 23 It is the rst time that compounds 1 and 4 have been isolated from family Compositae. ...
... Subgroup 2A (fractions 28-37), which was re-chromatographed over normal silica gel column using methylene chloride : methanol (100 : 0 till 0 : 100) to give sub-fractions (50-100), eluted with methylene chloride : methanol (85 : 15), when le for crystallization, precipitated a yellow powder (compound 17, 5 mg). Subgroup 2B (fractions 43-70) was re-chromatographed over reversed silica gel column RP-C 18 using water : methanol (100 : 0 till 0 : 100), yielded fractions (17)(18)(19)(20)(21)(22)(23), eluted with water : methanol (95 : 5), when le for crystallization, a yellow substance was precipitated (compound 18, 7 mg). ...
Discovering SARS-CoV-2 inhibitors from natural sources is still a target that has captured the interest of many researchers. In this study, the compounds (1–18) present in the methanolic extract of Helichrysum bracteatum were isolated, identified, and their in vitro inhibitory activities against SARS-CoV-2 main protease (Mpro) was evaluated using fluorescence resonance energy transfer assay (FRET-based assay). Based on 1D and 2D spectroscopic techniques, compounds (1–18) were identified as 24-β-ethyl-cholesta-5(6),22(23),25(26)-triene-3-ol (1), α-amyrin (2), linoleic acid (3), 24-β-ethyl-cholesta-5(6),22(23),25(26)-triene-3-O-β-D-glucoside (4), 1,3-propanediol-2-amino-1-(3′,4′-methylenedioxyphenyl) (5), (−)-(7R,8R,8′R)-acuminatolide (6), (+)-piperitol (7), 5,7,4′-trihydroxy-8,3′-dimethoxy flavanone (8), 5,7,4′-trihydroxy-6-methoxy flavanone (9), 4′,5-dihydroxy-3′,7,8-trimethoxyflavone (10), 5,7-dihydroxy-3′,4′,5′,8-tetramethoxy flavone (11), 1,3-propanediol-2-amino-1-(4′-hydroxy-3′-methoxyphenyl) (12), 3′,5′,5,7-tetrahydroxy-6-methoxyflavanone (13), simplexoside (piperitol-O-β-D-glucoside) (14), pinoresinol monomethyl ether-β-D-glucoside (15), orientin (16), luteolin-3′-O-β-D-glucoside (17), and 3,5-dicaffeoylquinic acid (18). Compounds 6, 12, and 14 showed comparable inhibitory activities against SARS-CoV-2 Mpro with IC50 values of 0.917 ± 0.05, 0.476 ± 0.02, and 0.610 ± 0.03 μM, respectively, compared with the control lopinavir with an IC50 value of 0.225 ± 0.01 μM. The other tested compounds showed considerable inhibitory activities. The molecular docking study for the tested compounds was carried out to correlate their binding modes and affinities for the SARS-CoV-2 Mpro enzyme with the in vitro results. Analyzing the results of the in vitro assay together with the obtained in silico results led to the conclusion that phenylpropanoids, lignans, and flavonoids could be considered suitable drug leads for developing anti-COVID-19 therapeutics. Moreover, the phenylpropanoid skeleton oxygenated at C3, C4 of the phenyl moiety and at C1, C3 of the propane parts constitute an essential core of the SARS-CoV-2 Mpro inhibitors, and thus could be proposed as a scaffold for the design of new anti-COVID-19 drugs.
... The equatorial location of the primary hydroxyl group at C23 was further supported by its 64.9 ppm downfield shift resonance. 19 The presence of ten sp 3 methylene carbons, six sp 3 methyl groups, six sp 3 methine, and one sp 2 methine carbon was confirmed (Figures S1a and S1b). The methyl and methine signals appeared positive, while the methylene signals appeared negative on DEPT 135. ...
... Except for the absence of a methyl group at C17, the 1 H and 13 C spectroscopic data are similar to those of other pentacyclic triterpenoids of the oleanane structural backbone. 19 The loss of the methyl group is expected to have occurred through the biosynthetic action(s) of cytochrome P450 enzymes. 24 Combretum quadrangulare provided the first evidence of a nortriterpenoid for genus. ...
... Compound 1, obtained as a white powder, gave a pink coloration in the Liebermann-Buchard's test, which is characteristic of triterpenes. The 1 H and 13 [17]. A signal for carbon, C-20, of the lupeol structure was observed on the 13 C NMR spectrum at δ 148.2 ppm, while seven singlet signals relevant for angular methyl groups appeared on the 1 H NMR spectrum between 0.8 and 1.7 ppm. ...
... and 81.0, assignable to a triterpene skeleton with one carbonyl acetate (CH3CO), one ethylenic double bond (C=CH), and one oxymethine (HCOH) group. The 1 H NMR spectrum ( Figure S6 in Supplementary Data) exhibited characteristic signals at δ 5.12 (t, 3.7 Hz, 1H), 4.49 (m, 1H), and 2.02 (s, 3H) due to protons at positions C-12, C-3, and the acetyl group from α-amyrin acetate [17]. All of the data above were similar to those published for α-amyrin acetate previously isolated from the same species [18]. ...
Diabetes contributes to the rising global death rate. Despite scientific advancements in understanding and managing diabetes, no single therapeutic agent has been identified to effectively treat and prevent its progression. Consequently, the exploration for new antidiabetic therapeutics continues. This study aimed to investigate the antidiabetic bioactive ethyl acetate fraction of F. lutea at the molecular level to understand the molecular interactions and ligand-protein binding. To do this, the fraction underwent column chromatography fractionation to yield five compounds: lupeol, stigmasterol, α-amyrin acetate, epicatechin, and epiafzelechin. These compounds were evaluated in vitro through α-glucosidase inhibition and glucose utilization assays in C2C12 muscle and H-4-11-E liver cells using standard methods. In silico analysis was conducted using molecular docking and ADMET studies. Epicatechin exhibited the most potent α-glucosidase inhibition (IC50 = 5.72 ± 2.7 µg/mL), while epiafzelechin stimulated superior glucose utilization in C2C12 muscle cells (33.35 ± 1.8%) and H-4-11-E liver cells (46.7 ± 1.2%) at a concentration of 250 µg/mL. The binding energies of the isolated compounds for glycogen phosphorylase (1NOI) and α-amylase (1OSE) were stronger (<−8.1) than those of the positive controls. Overall, all tested compounds exhibited characteristics indicative of their potential as antidiabetic agents; however, toxicity profiling predicted epiafzelechin and epicatechin as better alternatives. The ethyl acetate fraction and its compounds, particularly epiafzelechin, showed promise as antidiabetic agents. However, further comprehensive studies are necessary to validate these findings.
... The IR absorption revealed the presence of a O-H (3447 cm −1 ), C-H (2931 cm −1 ), carbonyl (1692 cm −1 ), C = C (1523 cm −1 ), and C-O (1034 cm −1 ) functionalities (figure S2). The 1 H NMR data (Tables S1) indicated six methyl groups at δ Η 1.05 (H 3 -23), 0.95 (H 3 -30), 0.92 (H 3 -25), 0.90 (H 3 -29), 0.84 (H 3 -24), and 0.77 (H 3 -26); one oxymethylene at δ Η 3.74 (1H, d, J = 12.0) & 3.47 (1H, d, J = 12.5); an oxymethine proton at δ Η 3.16, one olefinic proton at δ Η 5.61 (t, J = 2.5 Hz, H-12); in addition to ten methylene and three methine proton resonances ascribed to olean-12-en-28-oic acid skeleton (Mahato and Kundu 1994). Furthermore, the 1 H NMR spectrum displayed signals between δ Η 3.18 − 3.84 and an anomeric proton at δ Η 4.31 (d, J = 8.0 Hz, Glc-H-1) assigned to a D-glucose moiety. ...
... A closer look at the chemical shifts of C-12 and C-13, δ C 129.9 and 139.7 respectively in compounds 1-4, compare to 123.4 and 145.1 in compound 5, suggests that hydroxylation of C-27 leads to an up-field shift of C-12 of about 5.7 ppm and a corresponding downfield shift of C-13 of about 5.3 ppm. Further inside into structure confirms C-18 carbon in all compounds to be β-oriented with a chemical shift around δ 42.2 (Mahato and Kundu 1994). ...
Non-tuberculous mycobacteria infect mostly immunocompromised people. NTM infections incidence and prevalence increase has led to a public health problem. Combretum species are used as food by humans and animals, and medicinal purposes. The aim of the study was to evaluate the antimycobacterial effects of plant extracts from selected Combretum species on Mycobacterium smegmatis and Mycobacterium aurum as well as their mode of action on the most susceptible organisms. Antimycobacterial activity of the plant extracts was screened. Mycobacterium smegmatis was more susceptible to the extracts. The potent Combretum extracts were investigated for their effects on Rhodamine 6G transport and biofilms in M. smegmatis. The amount of Rhodamine 6G accumulated in M. smegmatis in the presence of extracts were also investigated. The C. zeyheri acetone extracts were the most potent efflux pump inhibitors. Surface extracts from C. zeyheri were the most potent disrupters and inhibitors of biofilms. The ethylacetate extract of another species, C. apiculatum lacked the effect on biofilms and this may be due to the lack of penetration of the extract into the already established biofilm. The ultra-high performance liquid chromatography UPHLC-MS/MS analysis of acetone extracts from C. zeyheri indicated the presence of cirsimaritin, quinic acid, and ampelopsin glucoside and these could have contributed to the antimycobacterial activities of the extract. In conclusion, phytochemicals from C. zeyheri, C. platypetalum, C. apicultum species used in traditional medicine in Zimbabwe showed antimycobacterial and antibiofilm activity and may be used as sources of lead compounds targeting non-tuberculosis infections caused by M. smegmatis.
... The structures of isolated compounds were determined by extensive spectroscopic experiments, including 1 H, 13 C-DEPT-Q, 1 H-1 H COSY, 1 H-13 C HSQC, NOESY, and 1 H-13 C HMBC (600 MHz) and HR-ESI-MS, and comparison with the respective literature data. The structure of compound 1 was concluded as oleanolic acid (Do et al., 2020), compound 4 was deduced as oleanolic acid 3-O-[β-D-glucopyranosyl-(1 → 4)-β-D-glucuronopyranoside] (Huan et al., 1998;Patkhullaeva et al., 1972;Stefaniak et al., 2018), and compound 6 was concluded as oleanolic acid (Mahato and Kundu, 1994). Compounds 1 and 4 are reported here for the first time in Olax genus (Tsakem et al., 2022). ...
... Other sugar peaks occurred between δ C 61.2-80.3. Compound 3, like 2, has an olean-12en-28-oic acid triterpene skeleton (Mahato and Kundu, 1994). A 1 H-13 C long-range correlation in the HMBC spectrum existed between the sugar anomerics at δ H 4.46 and δ C 89.8 (C-3). ...
Bioactivity-guided phytochemical fractionation of the methanol extract of Olax subscorpioidea root has led to the isolation of six triterpenes. Three of these compounds are previously undescribed triterpenoid saponins: oleanolic acid 3-O-[α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranosyl-(1 → 2)-6-O-methyl-β-D-glucuronopyranoside]-28-O-β-D-glucopyranosyl ester (2), oleanolic acid 3-O-[β-D-glucopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-β-D-glucopyranoside] (3), and oleanolic acid 3-O-[β-D-glucopyranosyl-(1 → 4)-6-O-methyl-β-D-glucuronopyranoside] ester (5). Other reported known compounds include two triterpene glycosides: oleanolic acid 3-O-[β-D-glucopyranosyl-(1 → 4)-6-O-methyl-β-D-glucuronopyranoside]-28-O-β-D-glucopyranosyl ester (1) and oleanolic acid 3-O-[β-D-glucopyranosyl-(1 → 4)-β-D-glucuronopyranoside] (4); and a triterpene acid, oleanolic acid (6). The structures of these compounds were elucidated by spectroscopic means. The isolated compounds were tested against human cervical cancer (HeLa), colorectal cancer (Caco-2) and breast cancer (MCF-7) cell lines using the in vitro 3-[4,5-dimethylthiazole-2-yl] 3,5-diphenyltetrazolium bromide (MTT) assay, with vincristine as positive control. The cytotoxicity assay showed that compounds 3 and 5 exhibited significant inhibitory effects on the HeLa cell line, with IC50 values of 7.42 ± 0.34 μM and 10.27 ± 1.26 μM; and moderate effects on MCF-7 (IC50 values, 36.67 ± 1.23 μM and 43.83 ± 0.65 μM) and Caco-2 (IC50 values, 35.83 ± 0.55 μM and 39.03 ± 4.38 μM, respectively) cell lines. They were also more selectively cytotoxic than vincristine against the cancer cell lines, when compared with cytotoxicity against the normal lung cell line MRC5.
... Alkaloids, such as morphine and vinblastine, are renowned for their analgesic, anticancer, and antimicrobial properties [7]. Interestingly, terpenes like taxol and limonene demonstrate anticancer, antiviral, and anti-inflammatory activities [8]. Tannins, effective as antioxidants and antimicrobials, also aid in wound healing and glucose regulation [9]. ...
... The analysis of 1 H and 13 C NMR data (Table 1) indicated that 1 was a triterpenoid saponin. In facts, its 1 H NMR spectrum displayed resonances of six methyl groups including four singlets [δ H 1.04 (H-23, s), 0.83 (H-24, s), 0.97 (H-25, s), and 0.88 (H-26, s)], two doublets [δ H 0.92 (d, J = 6.0 Hz) and 0.93 (d, J = 6.0 Hz)], and a characteristic olefinic proton at δ H 5.62 (H-12, br s) of an urs-12-en-type triterpenoid (Mahato and Kundu, 1994;Koffi et al., 2023). The 1 H NMR spectrum of 1 also displayed the signals of three anomeric protons at δ H 5.38 (d, J = 8.2 Hz, H-1′′′), 4.66 (d, J = 7.7 Hz, H-1′′) and 4.39 (d, J = 7.7 Hz, H-1′), which correlated in the HSQC with the carbon signals at δ C 95.6 (C-1′′′), 104.4 (C-1′′), and 105.3 (C-1′), respectively. ...
The chemical investigation of the CH 2 Cl 2 /MeOH (1:1, v/v) extract of the leaves and the stem bark of Brenania brieyi (Rubiaceae), which displayed antiplasmodial activity during preliminary screening resulted in the isolation of a new saponin (1), two new homoflavonoids (2 and 3) alongside 21 known compounds (4-24). Their structures were elucidated on the basis of their spectrometric and spectroscopic data, and by chemical reactions. All the compounds were isolated for the first time from the genus Brenania. Furthermore, fractions and some of the isolated compounds were assessed in vitro for their antiplasmodial potency against the chloroquine-sensitive strain of Plasmodium falciparum 3D7 (Pf3D7) and for their antibacterial activity against Escherichia coli 35218, Salmonella typhi CPC, Staphylococcus aureus 700098 and Pseudomonas aeruginosa HM 801. The extracts and fractions displayed moderate to good antiplasmodial activity with IC 50 values ranging from 12.17 to 32.63 µg/ mL. Compounds 5, 7, 19, and 21 exhibited moderate antiplasmodial activity while the other tested compounds were inactive. Regarding the antibacterial activity, compounds 2 and 23 exhibited potent antibacterial activity against at least one tested strain with MIC values between 8.313 and 19.423 µM.
... Based on the 1 H, 13 C-and DEPT NMR spectral data and comparison with NMR data available in the literature, compounds 1, 2 and 3 ( Figure 1) isolated from n-hexane extract were identified, respectively as epifriedelinol (ARAGAO; TOLEDO; FILHO, 1990), friedelin (HARBORNE, 1995), and canophyllol (MAHATO; KUNDU, 1994). These triterpenoids are quite common in plants. ...
Endopleura uchi is an important Amazonian species widely used in crafts, cooking and carpentry. The species is also widely used to treat uterine inflammation, intestinal diseases and reduce cholesterol, proving to be a promising field of study for the development of pharmaceuticals and the discovery of biologically active metabolites. Triterpenoids, coumarins and tannins were the secondary metabolites already isolated from the stem bark of the species. The leaves of E. uchi, on the other hand, have not yet been investigated and this work aimed to reveal the chemical potential present in this plant organ. The chemical study resulted in the isolation of three triterpenoids and the trihydroxybenzoic acid glycoside, bergenin. From the natural product bergenin, the pentaacetyl derivative was produced by semi-synthesis. Bergenin and its pentaacetyl derivative were used in phytotoxicity tests against the invasive pasture species Mimosa pudica. Bioassays revealed that the pentaacetylated derivative was the most phytotoxic.
... The NOESY spectrum revealed correlations between H-3/ H-23 and H-3/H-5, which pointed to the β-configuration of the oxygen atom at the C-3 position. In the 1 H-1 H COSY spectrum, the proton signal is correlated with the two proton signals of the methylene group at δ H 2.57 (br d, 1H, J = 12.2 Hz, H-15b) and δ H 1.77 (15a).Based on the broad single peak of the hydrogen proton on the methylene carbon in the 1 H-NMR, HMBC and DEPT spectra, it is inferred that the hydroxyl group at position 16 should be in the alpha configuration (Shashi and Mahato, 1994). Taken together, the spectroscopic of the aglycone closely matched that of caulophyllogenin (Strigina et al., 1974). ...
Since ancient times, plants have provided humans with important bioactive compounds for the treatment of various diseases. Nine compounds were isolated from the roots and rhizomes of Caulophyllum robustum (a plant in the family Panaxaceae), including two new saponins C. Spanion A and C. Spanion B (1-2) and seven known saponins (3-9). The cytotoxicity of these compounds on human cancer cell lines was analyzed using MTT method. Compounds 6 and 9 exhibit cytotoxicity towards these three types of human cancer cells (<10 μM). By utilizing the SEA platform for target prediction, a common tumor related target CD81 was identified. The molecular docking of saponins 1, 2, 6, and 9 with CD81 protein showed strong binding affinities ranging from -4.5 to -7.1 kcal/mol. Research has shown that these compounds can become potential anti-tumor drugs. Further research is still recommended to understand its exact molecular mechanism and toxicological effects.
... Lupeol is a naturally existing pentacyclic triterpenoid found in a variety of plants, fruits, and vegetables, including mangoes (Mangifera indica), olives (Olea europaea), and strawberries (Fragaria ananassa), as well as medicinal plants like Aloe vera and Andrographis paniculata (Saleem, 2009;Gallo and Sarachine, 2009). Lupeol is structurally defined by its lupane structure, critical in determining its distinct biochemical properties and wide range of biological activities (Mahato and Kundu, 1994). Lupeol's pharmacological relevance has been established, with research demonstrating its powerful anti-inflammatory, antioxidant, antibacterial, anticancer, and hepatoprotective activities. ...
Lupeol, a pentacyclic triterpenoid found in a variety of fruits, vegetables, and medicinal plants, has received a lot of attention due to its diverse pharmacological properties and possible therapeutic applications. A thorough literature search was carried out to acquire important information on lupeol's pharmacological actions and mechanisms of lupeol. Key databases, such as Google scholar, Science Direct, Springer Link, PubMed and Scopus, were used to ensure an extensive review of available literature. The studies included were selected based on criteria requiring peer-reviewed articles, clinical studies, and experimental research published mainly, focusing on the pharmacological properties, bioactivity, and mechanisms of action of lupeol. Lupeol's diverse beneficial effects, which include anti-inflammatory, antioxidant, antimicrobial, anticancer, and hepatoprotective properties, are attributed to its ability to modulate key molecular pathways involved in inflammation, oxidative stress, cellular proliferation, and programmed cell death. Lupeol inhibits the production of pro-inflammatory cytokines such as TNF-, IL-1, and IL-6 by downregulating the NF-B signaling pathway, leading to reduced inflammation and tissue damage. Its antioxidant properties, which include scavenging reactive oxygen species and increasing the activity of endogenous antioxidant enzymes, help it defend against diseases associated with oxidative stress, such as neurological and cardiovascular problems. Furthermore, lupeol's anticancer capabilities have been extensively studied, with results demonstrating its capacity to inhibit tumor growth, induce apoptosis, and prevent metastasis in a variety of cancer models. This review offers an in-depth analysis of current research on lupeol, highlighting its chemical structure, pharmacological properties, and the molecular mechanisms underlying its functions. By examining lupeol's multifaceted medicinal potential, this study explores its promise in developing innovative treatments for various chronic diseases. Additionally, the review identifies key areas for future investigation, outlining research opportunities to deepen the understanding of lupeol's clinical viability, optimize its therapeutic efficacy, and assess its safety across a broader spectrum of applications.
... The 1D and 2D NMR data of OSS4a agreed with those we recently reported in the root extract of O. subscorpioidea for oleanolic acid (Figure 1). The data also agreed with the literature values for oleanolic acid (Mahato & Kundu, 1994;Seebacher et al., 2003). To the best of our knowledge, this is the first report of the isolation and NMR analysis of OA from O. subscorpioidea stem bark. ...
... The various extracts were purified by a combination of chromatographic techniques using silica gel and Sephadex LH-20 as the stationary phase to afford 7 known compounds, which were subjected to 1 H-NMR and 13 C-NMR spectroscopy. And were identified by comparing their spectroscopic data with those reported in the literature as stigmasterol [14], β-sistosterol [15], lupéol [16], betulinic acid [17], oleanolic acid, lantic acid [18], lantanilic acid [19]. Only five of these compounds were used in this study. ...
... The 1 H NMR (400 MHz) and 13 ...
Objective: The Knema genus contains various naturally occurring secondary metabolites with pharmacological potential, including antitumor, neuroprotective, antidiabetic, and hepatoprotective activities. This study focuses on identifying nitric oxide production inhibitors from Vietnamese Knema globularia. Methods: The secondary metabolites were isolated using several chromatographic techniques. Their chemical structures were determined using nuclear magnetic resonance (NMR) spectroscopy and compared with published literature. The anti-inflammatory effect was evaluated using the Griess assay, and protein interactions were investigated through docking studies. Results: Based on their anti-inflammatory activity, six compounds (1-6) were isolated from Vietnamese K. globularia. These compounds were identified as lupeol (1), formononetin (2), isoliquiritigenin (3), 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]propane-1,3-diol (4), (+)-catechin (5), and (−)-epicatechin (6). For the first time, compounds 1, 3, and 4 were reported from Vietnamese K. globularia. All isolated compounds were tested against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW264.7 cells to assess their anti-inflammatory potential. Compound 5 exhibited the highest inhibitory activity, with an IC50 value of 5.61 μM, followed by compounds 3 and 6, with IC50 values of 6.76 and 11.52 μM, respectively. However, compounds 1, 2, and 4 showed inactivity with IC50 values exceeding 30 μM. Molecular docking was then employed to investigate the affinity and interactions between compounds 3, 5, and 6 and proteins involved in inflammation, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and interleukin-8 (IL-8), along with ADMET (absorption, distribution, metabolism, excretion, and toxicity) predictions. Conclusion: These findings suggest that the active constituents derived from Vietnamese K. globularia have the potential as anti-inflammatory agents worthy of further exploration and development.
... Lupeol (3), lupenone (4), and sitostenone (7) were directly identified by comparison of NMR registered data with literature data for these compounds. 26,27 The mixture of sitosterol and stigmasterol was identified by TLC comparing with pure standards and also NMR data analysis. ...
This study describes the chemical composition and biological activities of extracts and compounds obtained from the roots of Bowdichia virgilioides (Fabaceae). A mixture of very long-chain free fatty acids (VLFAs) and pure compounds, namely isocordoin, cordoin, lupeol, lupenone, β-sitosterol, stigmasterol, and sitostenone, were isolated from the soluble fraction of the methanol extract by using sequential column chromatography procedures. The molecular structures of the compounds were determined using infrared (IR), nuclear magnetic resonance (NMR), and mass spectrometry (MS) techniques. Notably, this is the first report of the occurrence of both chalcones within this plant genus. Besides, the VLFAs were identified by electrospray ionization mass spectrometry (ESIMS) and the presence of these compounds in roots is suggested to be an adaptive response to environmental stress, which exhibited moderate antioxidant properties when tested against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and in the β-carotene/linolenic acid auto-oxidation assay. However, the MeOH soluble fraction demonstrated significant toxicity in the brine shrimp lethality assay.
... Sub-fraction 5-20 presented a compound that appeared as a white crystal (130 mg). This compound was identified by their spectral data (IR, 1 H-NMR, and 13 C-NMR) in comparison with literature values as 2β, 3β, 19α-trihydroxyursolic acid (Alves et al., 2014;Mahato & Kundu, 1994;Niero et al., 1999;Taketa et al., 2000). ...
Rubus imperialis (Rosaceae) is a Brazilian medicinal plant that already exhibited therapeutical perspectives. However, previous studies revealed cellular and/or genetic toxicity of extracts from aerial parts of this plant, as well as other species of the Rubus genus. Being 2β,3β‐19α‐trihydroxyursolic acid (2B) one of the major compounds of this plant, with proven pharmacological effect, it is important to investigate the biosafety of this isolated compound. Therefore, in the present study, (2B) was tested by several cytogenotoxic endpoints up to 20 μg/ml in human hepatoma HepG2/C3A cells. The test compound did not produce any decreased cell viability, DNA damage, chromosomal mutations, cell cycle changes, or apoptotic effects in the tested cells. Additionally, RT‐qPCR analysis revealed the downregulation of CYP3A4 (metabolism), M‐TOR (cell death), and CDKN1A (cell cycle) genes. Under the experimental conditions used, the 2B compound did not show cytogenotoxic activity after a single exposure to HepG2/C3A human cells.
... The 1D and 2D NMR data of OSS4a agreed with those we recently reported in the root extract of O. subscorpioidea for oleanolic acid (Figure 1). The data also agreed with the literature values for oleanolic acid (Mahato & Kundu, 1994;Seebacher et al., 2003). To the best of our knowledge, this is the first report of the isolation and NMR analysis of OA from O. subscorpioidea stem bark. ...
... Anisaldehyde sulphuric reagent color was used to the visualize spots. The compound was identified by their spectral data (IR, 1 H-NMR and 13 C-NMR) in comparison with literature values as niga-ichigoside F1 (265 mg) (Mahato & Kundu, 1994;Niero et al., 1999;Tonin et al., 2016;Um et al., 2001). The pure compound was placed in a desiccator on active silica gel until further use. ...
Rubus imperialis Chum. Schl. (Rosaceae) have demonstrated some pharmacological activities, including gastroprotective action. However, genotoxic effects of R. imperialis extract was also reported. Since niga‐ichigoside F1 (NIF1) is a major compound of this plant species, and which has proven pharmacological properties, it is essential to investigate whether this compound is responsible for the observed toxicity. Therefore, the objective of this study was to analyze the effects of NIF1 on HepG2/C3A cells for possible cytogenotoxicity, cell cycle and apoptosis influence, and expression of genes linked to the DNA damage, cell cycle, cell death, and xenobiotic metabolism. The results showed no cytogenotoxic effects of NIF1 at concentrations between 0.1 and 20 μg/ml. Flow cytometry also showed no cell cycle or apoptosis disturbance. In the gene expression analysis, none of the seven genes investigated showed altered expression. The data indicate that NIF1 has no cytogenotoxic effects, and no interruption of the cell cycle, or induction of apoptosis, apparently not being responsible for the cytotoxic effects observed in the crude extract of R. imperialis .
... The 13 C NMR spectrum (Table S1) of compound 1 displayed forty-two resonances signals which coupled with the HSQC spectrum allow us to distinguish among other, seven methyl groups at δ C 32.2 (C-29), 27.0 (C-23), 26.0 (C-27), 22.8 (C-30), 15.9 (C-26), 15.5 (C-24) and 14.7 (C-25); two oxymethine carbons at δ C 89.8 (C-3) and 66.3 (C-16) and one oxymethylene carbon at δ C 67.4 (C-28). The signals of the two olefinic carbons at δ C 142.8 (C-13) and 122.5 (C-12) were an indication of an olean-12-ene skeleton (Maeda et al. 1994;Mahato and Kundu 1994;Ageta et al. 1995). On this basis, the aglycone moiety of compound 1 was established to be longispinogenin (Mahato and Pal 1987). ...
The chemical investigation of the aerial part of Abrus canescens led to isolation of a new triterpenoid glycoside named Canescensoside (1) and four known compounds including longispinogenin-3-O-β-D-glucuronopyranoside (2), β-sitosterol-3-O-β-D-glucoside (3), apigenin-7-O-β-D-glucopyranoside (4) and apigenin-7-O-[α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranoside] (5). Structures of compounds were assigned by interpretation of their spectral data, mainly 1D and 2D NMR, HRESIMS, and by comparison with the reported data. The MeOH extract, EtOAc and n-BuOH fractions as well as isolated compounds were tested for their antibacterial activities against four bacteria strains among which, two Gram-negative (Pseudomonas aeruginosa ATCC 76110 and Escherichia coli ATCC 8739) and two Gram-positive (Enterococcus faecalis ATCC 29212 and Staphylococcus aureus ATCC 25923) bacteria using the broth microdilution method. The MeOH extract and EtOAc fraction exhibited significant activities (MIC values ranging from 128 to 512 μg/mL) against all the tested bacteria. Compounds 2 and 3 showed the lowest MIC values of 55.47 and 50.40 µM, respectively.
... The spectral data of the other known compounds were consistent with those reported in previous studies as follows: rugosin B (2) [15], rugosin A methyl ester (3) [16], rugosin A (4) [15], eugeniin (5), tellimagrandin I (6) [17], 1,2,3,4,6-penta-O-galloyl-β-D-glucose (7) [18], 2,3,4,6-tetra-O-galloyl-D-glucose (8), 1,2,3,6-tetra-O-galloyl-β-D-glucose (9) [19], quercetin 3-glucuronic acid (10) [20], kaempferol 8-O-glucuronic acid (11), kaempferol 3-glucuronic methyl ester (12), kaempferol 3-glucuronic acid (13) [21], catechin (14) [22], tomentic acid (15), benthamic acid (16) [23], ursolic acid (17) [24], rosamutin (18) [25], arjunetin (19) [26], methylgallate (21), methylprotocatechuate (22), salicylic acid (23) [27], gaultherin (24) [28], methyl gallate 3-O-β-D-glucopyranoside (25), (R/S)-rhododendrin (26) [29], salidroside (27) [30], and undulatoside A (28) [31] as shown in Figure 1. In addition, 26 known compounds (2-19 and 21-27) were identified by comparing their physical and spectroscopic data with those reported in the mentioned literature, respectively. ...
In our search for bioactive components, various chromatographic separations of the organic fractions from Filipendula glaberrima leaves led to the isolation of a new ellagitannin and a triterpenoid, along with 26 known compounds. The structures of the isolates were determined based on their spectroscopic properties and chemical evidence, which were then evaluated for their antioxidant activities, inhibitory activities on 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and foam cell formation in THP-1 cells to prevent atherosclerosis. Rugosin B methyl ester (1) showed the best HMG-CoA reductase inhibition and significantly reduced ox-low-density lipoprotein-induced THP-1 macrophage-derived foam cell formation at 25 µM. In addition, no cytotoxicity was observed in THP-1 cells at 50 μg/mL of all extracts in the macrophage foam cell formation assay. Therefore, F. glaberrima extract containing 1 is promising in the development of dietary supplements due to its potential behavior as a novel source of nutrients for preventing and treating atherosclerosis.
... The phytochemical investigation of the aerial parts of Psychotria schlechtendaliana afforded seven compounds (Figure 1): the alkaloids 4-N-oxide-harmane (1) 13 and strictosidinic acid (2), 14 the steroids sitosterol (3) and stigmasterol (4) 15 and the triterpenes α-amyrin (5), β-amyrin (6) and betulinic acid (7). 16 The chemical structures were characterized by 1 H, 13 C, and 2D NMR analysis, followed by comparison with the literature. Table 1). ...
Phytochemical study of Psychotria schlechtendaliana (Rubiaceae) aerial parts resulted in the isolation of alkaloids 4-N-oxide harmane (1) and strictosidinic acid (2), and the terpenoids sitosterol, estigmasterol, α-amyrin, β-amyrin and betulinic acid. The crude extract (CE), its fractions (hexane FH, chloroform FC, ethyl acetate FEA, hydromethanolic FHM, alkaloidal chloroform FCOH, alkaloidal aqueous FAq) and majority alkaloid (1) were investigated for their antiproliferative potential against nine human tumor cells lines and one non-tumoral human cell line (HaCat). CE, FH and FEA fractions exhibited strong growth inhibition for ovary cells (OVCAR-3, GI50 = 5.89; 1.36 and 6.59 μg mL-1, respectively) and FC, FH and FAq fractions showed potent activity on the growth of leukemia cell lines (K562, GI50 = 1.92; 7.23 and 8.81 μg mL-1, respectively). Compound 1 exhibited selective antiproliferative activity to breast cancer (MCF-7, GI50 = 32.7 μg mL-1) and was non-toxic to HaCat cells. To evaluate the anti-inflammatory effect, models of ear edema induced by croton oil and the enzyme myeloperoxidase (MPO) were used. FH and FC fractions exhibited antiinflammatory effect and reduce ear edema compared to the control group. These fractions showed results superior to those exhibited by indomethacin (75.1%), FH (97.5%) and FC (95.5%) fractions.
... On observe également sur ce spectre un multiplet d'un proton à δH 3,12 ppm attribuable au proton d'un hydroxyméthine et cinq singulets de trois protons chacun entre δH 0,75-0,97 ppm correspondant à cinq groupements méthyles angulaires. [14]. Son spectre RMN 13 C présente trente signaux correspondant à trente atomes de carbones. ...
Introduction : Vernonia conferta est une espèce utilisée par les populations camerounaises dans la prise en charge des plaies. L’objectif de ce travail était de déterminer la composition chimique et d’évaluer les propriétés antimicrobiennes de cette plante. Méthodologie : Nous avons mené une étude expérimentale. Le matériel végétal était constitué d’écorces de tronc de V. conferta récoltées dans la région du Centre, département de la Mefou et Afamba, localité de Nkolafamba, L’identification du spécimen a été effectuée à l’Herbier National du Cameroun sous le n° 10046. Le matériel a été nettoyé, séché durant 14 jours à l’abri du soleil, puis pulvérisé dans un broyeur mécanique. L’extraction a été faite par double macération de 72h dans 11 L de MeOH de la poudre d’écorces de V. conferta. Le mélange a été filtré sur du papier filtre Whatman N°3, le filtrat concentré à l’évaporateur rotatif Heidolph® (Hei-VAP ML/G3). L’extrait sec a été conservé à température ambiante à l’abri du soleil. Le criblage phytochimique qualitatif a été réalisé en utilisant les protocoles standards d’Harbonne de 1998. Pour l’isolement et la caractérisation des molécules, l’extrait brut a été dissout dans du MeOH et fixé sur une quantité équivalente de silice (de granulométrie 60 – 200μm / 60A) puis séché à température ambiante. Le mélange a été ensuite séparé sur une colonne chromatographique ouverte éluée au système de solvants n-hexane/AcOEt à des polarités croissantes. La composition qualitative des fractions recueillies a été déterminée à l’aide de la CCM. L’élucidation des structures des composés isolés a été faite grâce aux méthodes de RMN 1H et 13C. L’évaluation de l’activité antimicrobienne a été réalisée par la détermination des CMI et CMB. Pour les CMI, les tests ont été faits en triplicate dans les microplaques stériles de 96 puits. Cinq dilutions d’ordre 2 ont été réalisées (de 50 μg /mL à 1,56 μg/mL). L’incubation a été faite pendant 24 h à 37 °C (bactéries) et à 28 °C (fungi). La croissance des microorganismes a été observée grâce à un indicateur coloré l’iodonitrotétrazolium qui virait au rose en présence de bactéries viables. La CMI est la plus faible concentration à laquelle l’extrait a empêché la croissance visible des bactéries et fungi. L’activité de l’extrait a été classé en : i) très forte, CMI ≤ 5 μg/mL ; ii) forte, 5 μg/mL ≤ CMI ≤ 50 μg/mL ; iii) modérée, 50 μg/mL ≤ CMI ≤ 325 μg/mL et iv) faible, CMI> 325 μg/mL Concernant les CMB, L’ensemencement a été effectué à partir des puits de CMI, sur les géloses Muller Hinton e et Sabouraud et l’incubation s’est faite à 37 °C pendant 24 h (bactéries) et 28 °C (champignons). La CMB/CMF est la plus petite concentration à laquelle l’extrait a empêché la croissance visible des microorganisemes après repiquage. L’effet de l’extrait a été déterminé par le rapport CMB ou CMF/CMI : ˂ 1, «bactéricide/fongicide absolu», ≤ 4, «bactéricide/fongicide», > 4, «bactériostatique /fongistatique». Résultats : le rendement d’extraction a été de 2,66%, les composés phénoliques et terpénoïdes ont été révélés. Un mélange de β‐sitostérol et de stigmastérol, ainsi que l’acide bétulinique, ont été isolés. L’extrait méthanolique a montré une forte activité antibactérienne sur les souches de S. aureus et E. coli avec une CMI de 1.25 µg / ml et une très forte activité antifongique sur la souche de C. albicans avec une CMI de 0,78 µg / ml, de plus l’effet a été bactéricide et fongistatique. Conclusion : ces résultats démontrent que l’extrait méthanolique d’écorces de V. conferta présente des propriétés antimicrobiennes.
... On observe également sur ce spectre un multiplet d'un proton à δH 3,12 ppm attribuable au proton d'un hydroxyméthine et cinq singulets de trois protons chacun entre δH 0,75-0,97 ppm correspondant à cinq groupements méthyles angulaires. [14]. Son spectre RMN 13 C présente trente signaux correspondant à trente atomes de carbones. ...
... The fraction rich in α-(67%) and β-amyrin (33%) was submitted to further purification. The identification of these isomers was performed by infrared spectrophotometry (KBr) Vmax cm -1 (3300, 1480 and 1050), 1 H-NMR (500 MHz, CDCl 3 ), 13 C (125 MHz, CDCl 3 ), melting point (179-181°C) (Mahato & Kundu, 1994). The final product, a mixture of α-AMY and β-AMY, was a white amorphous powder with slight odor. ...
The isomeric mixture of alpha and beta amyrin (AMY), present in the resin of Protium heptaphyllum, is popularly used as anti-inflammatory and anti-ulcer. The literature has been demonstrating pharmacological activities of these triterpenes in the central and peripheral nervous systems, and in the gastrointestinal and immunological systems. This study traces a toxicological profile of amyrin, aiming to provide information that may clarify its safety. Nine female Wistar rats (170 to 200 g) were divided into three groups of three animals each (control, amyrin 300 and amyrin 2000 mg kg-1, p.o.), which were evaluated by protocols preconized by the Organization for Economic Co-operation and Development (OECD). Open field Test and Malone Hippocratic Screening Scale were performed. AMY, mostly at 2000 mg kg-1, reduced the number of crossings by 57% vs. saline (22.67 ± 2.40) and the number of rearing by 53% vs. saline (42.67 ± 2.96), but increased the number of grooming by 26% vs. saline (1.66 ± 0.33). AMY (2000 mg kg-1) increased the serum glucose by 77% vs. saline (126.70 ± 4.33 mg dL-1), triglycerides by 50% vs. saline (78.67 ± 2.18 mg dL-1) and uric acid by 65% vs. saline (0.73 ± 0.03 mg dL-1). AMY induced vascular congestion and hemorrhage in the liver, spleen and cerebral cortex. Renal changes (cellular damage, inflammatory infiltrate, tubular protein deposition and glomeruli atrophy) were also seen. In conclusion, AMY decreased rat locomotor activity, caused minor biochemical changes, and altered the morphology of the kidney. The present study may contribute to deepen the knowledge about the safety of AMY, aiming the development of a novel pharmacological product.
Phytochemical studies of ethanolic extract from leaves of Byrsonima intermedia, B. cocoolobifolia and B. verbacifolia (collected in Mogi Mirim, SP, Brazil) afforded the following triterpenoids: mixtures ofthe a+ B-amyrin and ursolic acid + oleanolic acid, and 2a-hydroxi ursolic acid of B. cocoolobifolia; mixtures of a + B-amyrin and ursolic acid + oleanolic acid of B. verbacifolia; lupeol and B-amyrin of B. intermedia. The structures of these compounds were identified by spectroscopic methods (IR, ¹³C and ¹ H NMR).
KEY WORDS: Malpighiaceae; Byrsonima ; Triterpeno
Four triterpenes were isolated from the ethanolic extract of branches Vitis vinifera (Vitaceae) and identified as, lupeol, 28-hydroxylupeol, 30-hydroxy-b-amirin and l 9ahydroxy-a-amirin, by spectroscopic data.
KEY WORDS: Triterpens; ethanolic extract; Vitis vinifera, Vitaceae.
Chemical studies of Mangifera indica twigs yielded two compounds, identified as taraxerol (1) and methyl gallate (2). The galloyl moiety was suggested as a potential scaffold that can interfere with proteases by previous biological investigations on SARS-CoV-2 main protease (Mpro) inhibitors in combination with docking studies. Therefore, a series of 13 gallate esters were prepared by treating gallic acid with natural and non-natural alcohols. Their inhibitory effects were evaluated against Mpro and NS2B/NS3 of Zika and Dengue viruses. Among the obtained compounds, 2e and 2i were the most potent against Mpro with IC50 values of 2.60 and 4.0 μM, respectively. Compounds 2f and 2g were more potent than others against ZIKV protease with IC50 values of 2.7 and 1.9 μM, respectively. The bioactivity profile against DENV NS2B/NS3 was different with 2e and 2f showing moderate inhibition with IC50 values of 66.0 and 59.29 μM, respectively. It was found that 2f and 2g inhibited ZIKV NS2B/NS3 via a noncompetitive mechanism. The study also showed that 2e and 2f could exert noncompetitive inhibition at the previously described allosteric pocket of flaviviral NS2B/NS3 proteases. Molecular docking revealed different types of interactions among the most prominent were hydrogen bonding with the galloyl moiety.
Four novel triterpenoid saponins, 1α,3β,23-trihydroxy-olean-12-en-28-oic acid 28-O-β-glycopyranoside ester (1), 1α,3β,23-trihydroxy-urs-12-en-28-oic acid 28-O-β-glycopyranoside ester (2), 3-O-β-galloyl-1α,23-dihydroxy-olean-12-en-28-oic acid 28-O-β-glycopyranoside ester (3) and 3-O-β-galloyl-1α,23-dihydroxy-urs-12-en-28-oic acid 28-O-β-glycopyranoside ester (4) and two new pentacyclic triterpenoids, 3-O-β-trans-p-coumaroyl-1α-hydroxy-urs-12-en-28-oic acid (5) and 3-O-β-cis-p-coumaroyl-1α-hydroxy-urs-12-en-28-oic acid (6), together with six known compounds were isolated from the ethanolic extracts of Miconia burchellii leaves and stem bark. Their structures were established by HR-MS, 1D and 2D NMR and comparison with literature data. Additionally, the antimicrobial activity of the leaves and stem bark extracts and fractions was evaluated using the micro broth dilution technique. The crude extract, the ethyl acetate and methanol fractions of the stem bark were the most active against the tested bacteria, showing growth inhibition of both Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa). To the best of our knowledge, this is the first study to report on the antimicrobial activity of M. burchellii.
Chrysobalanus icaco (Chrysobalanaceae), é um arbusto, no Brasil, tem ocorrência em todo litoral e no bioma amazônico, conhecida como abajurú, abajerú, bajerú, guajurú, entre outros nomes populares. Na medicina popular é usada principalmente no controle da glicemia de diabéticos, disenterias e leucorreias. Há na literatura cientifica estudos que confirmam seus efeitos antidiabéticos. Do ponto de vista químico a espécie caracteriza- se como bioprodutora de compostos terpênicos e fenólicos. O objetivo deste trabalho é contribuir com os estudos químicos da espécie C. icaco, considerando as suas relevantes atividades farmacológicas. Neste trabalho apresentamos o isolamento e caracterização de dois triterpenos e três flavonoides além do produto obtido por reação de acetilação de uma fração acetato de etila identificado como 2α, 3β-diacetoxi-6β-hidroxi-olean-12-en-28-oato de [β-D-triacetoxi-glicopiranosil (2→1) – β - triacetoxi-xilopiranosil]. A determinação estrutural das substâncias foi feita através da análise de espectros de ressonância magnética nuclear 1D e 2D e espectrometria de massas HR-ESI-MS e comparação com valores registrados na literatura.
The genus Plumeria of the Apocynaceae family has a rich history of traditional medicines supported by empirical evidences. This review consolidates diverse biological attributes, phytochemical compositions, physical properties (melting point, shape, optical rotation, etc.), and analytical data (UV, IR, Mass spectroscopic data, elemental analysis) of various species of Plumeria. The review covered the chemistry of wide range of natural compounds like iridoids, triterpenoids, alkaloids, flavonoids, steroids, cardiac glycosides, quinones, anthocyanins, cardenolides, fatty acid esters, lignans, coumarins, etc. found in various species of the genus Plumeria. Analytical techniques including chromatography, IR, UV, and mass spectroscopy have significantly contributed to elucidating the complex chemical profiles of extracts of various species of Plumeria which are systematically presented in a tabular format. The review also defines the historical background, geographical distribution, and traditional uses of various species of the genus Plumeria. The review also includes the mechanisms of action and biotransformation of compounds, providing a deeper understanding of their therapeutic potential. The comprehensive review reveals the significance of the natural products isolated from a number of species of genus Plumeria. It is also suggestive that there is an extensive scope for further investigation to explore new therapeutic components of the genus Plumeria.
Oligosaccharides are biologically active components of any mammalian milk. Due to
various compositions of its monosaccharide contents i.e. Glucose, Galactose, GlcNAc,
GalNAc, Fucose and Sialic acid they show varied biological activities. The configuration of
glycosidic linkages and conformation of monosaccharides also play a decisive role in the
biological activity of these naturally occurring oligosaccharides. The position of glycosidic
linkages between different monosaccharides, in a straight or branched chain also plays a
definite role in the biological activity of oligosaccharides isolated from particular milk.
Besides the common milks like cow, buffalo, goat and sheep, some other rare milks i.e.
mare, yak, camel and elephant has also been investigated for their oligosaccharide
contents. In the present article we are describing the oligosaccharide contents of mare
milk. Horse/mare is a robust mammal used for transport and other purposes. Its milk
shows prebiotic, anti-adhesive and anti-inflammatory, lowers cholesterol intake as well as
to control cardiovascular diseases, cures Crohn’s disease, ulcerative colitis as well as
hepatitis and chronic gastric ulcers. In view of its biological activity a number of milk
oligosaccharides have been isolated from mare milk and their structures elucidated by chemical degradation, chemical transformation and spectroscopic techniques like NMR (1D and 2D) 1H, 13C, HSQC, HMBC, COSY, TOCSY and Mass spectrometry. This paper deals in detail with the techniques used in isolation, purification, structure elucidation and biological activity of Mare milk oligosaccharides. Keywords: Horse/Mare, Milk oligosaccharides, Structure elucidation, NMR, Biological activity.
The apicomplexan parasite Toxoplasma gondii causes toxoplasmosis, a ubiquitous and cosmopolitan parasitosis, generally asymptomatic and potentially dangerous for the fetus and highly immunocompromised patients. Pyrimethamine and sulfadiazine, supplemented with folic acid, are the drugs of choice to treating the disease, but they produce severe side effects and treatments fail due to drug resistance. New anti-Toxoplasma compounds are needed, and natural compounds can be a good source for obtaining them. The antiparasitic activity of 40 polar and non-polar extracts of eight antiparasitic medicinal plants used in Côte d'Ivoire, and selected based on ethnopharmacological survey, were evaluated in vitro against T. gondii. Among them, the hydromethanolic extract of the Elaeis guineensis leaves exhibited the best parasite growth inhibition (94% ± 0.07) at 25 μg/mL without being cytotoxic at the same dose. The fractionation of this extract did not allow the recovery of antitoxoplasmic activity in its individualized fractions. The ¹³ C-NMR based dereplication of the produced fractions and the purification of one of them highlighted the presence of saccharides, terpenes, flavonoids, cardanols and aliphatic acids. The obtained clusters of ¹³ C chemical shifts were assigned to their corresponding molecular structures with the help of open online databases, resulting in nine unambiguously identified compounds, whereas the purification of one of these fractions led to the identification of palmitic acid (10), palmitic acid methyl ester (11), 3-[12(E)-pentadecenyl]phenol (12), 3-[14(E)-heptadecenyl]phenol (13), ursolic acid (14) and stigmasta-4,24(28)-dien-3-one (15). A synergistic effect between these metabolites is thought to be responsible for the anti-Toxoplasma activity.
Nine compounds were isolated and identified from ethanolic extracts of Saposhnikovia divaricata , including one new alkaloid ( 1 ), one new pentacyclic triterpenoid ( 9 ), and seven known alkaloids ( 2 – 8 ). Structural elucidation of compounds 1 and 9 was established by 1D and 2D NMR spectra referring to the literature, together with high-resolution mass spectrometric analysis. All compounds were evaluated for antiproliferative activity against two cancer cell lines (LN229, A549) in vitro . Compounds ( 1 – 9 ) showed no significant antiproliferative activity.
The new flavonoid 4’‐O‐methylepigallocatechin 5‐O‐β‐D‐glucopyranoside (1), along with four known triterpenes (2‐4), a steroid (6), and a flavonoid (7) were isolated from the ethyl acetate extract of Maytenus quadrangulata leaves. The chemical structures of the isolated compounds were determined through analysis of 1D NMR (1H and 13C) spectroscopic data, in addition to 2D NMR and spectrometric (MS) data for compound 1. This is the first report of the isolation of compounds 3‐O‐β‐D‐glucosyl‐β‐sitosterol (6) and 4’‐O‐methylepigallocatechin (7) from this species. Compounds 1 and 7 were evaluated against the bacteria Staphylococcus aureus and Klebsiella pneumoniae, but neither exhibited activity even at the highest concentration tested.
By investigating the chemical constituents of the roots of Launaea sarmentosa , collected at Can Gio beach, Can Gio district, Ho Chi Minh city, nine compounds were isolated including α‐amyrin acetate ( 1 ), β‐amyrin acetate ( 2 ), lupeol acetate ( 3 ), ψ‐taraksasterol acetate ( 4 ), luteolin ( 5 ), 4‐allyl‐2,6‐dimethoxyphenol glucopyranoside ( 6 ), scorzoside ( 7 ), ixerisoside D ( 8 ) and 9α‐hydroxypinoresinol ( 9 ). To the best of our knowledge, all compounds were reported in other species, but this is the first time they were known in L. sarmentosa . Four compounds ( 1 ‐ 4 ) from the n ‐hexane extract were identified by 4‐dimethylaminopyridine‐catalyzed benzoylation. Their chemical structures were elucidated by means of 1D and 2D NMR, HR‐ESI‐MS data analysis and compared with those reported in the literature.
Combretum indicum belonging to the Combretaceae family possessed many bioactivities such as pain relief, antipyretic, antimicrobial, antioxidant, anticancer, etc. However, there had not much chemically studied on this species, especially, in Viet Nam. Herein, eight compounds consisting of asiatic acid ( 1 ), arjunolic acid ( 2 ), oleanolic acid ( 3 ), benzyl‐β‐D‐xylopyranosyl‐(1′′ → 6′)‐β‐D‐glucopyranoside ( 4 ), nudifloric acid ( 5 ), vanillin ( 6 ), gallic acid ( 7 ), and β ‐sitosterol ( 8 ) were reported from the Combretum indicum leaves collected at Ho Chi Minh City, Viet Nam. Their chemical structures were elucidated by the MS and NMR spectroscopic analysis as well as the comparison of their NMR data with the published data. Compounds 1 , 3 , 4 , 5 , and 6 were notified for the first time from Combretum indicum .
Medicinal plants have been largely used for the treatment of several illnesses including lifestyle diseases. The observed pharmacological properties of these plants are mainly attributed to the presence of secondary metabolites. Several of these secondary metabolites have been isolated, characterized, and assessed for their biological potential against lifestyle diseases. Reports on the chemical investigation of some medicinal plants involved in the management of lifestyle diseases such as diabetes, respiratory chronic diseases, cancer, and cardiovascular diseases have revealed that the main classes of compounds involved are phenolic compounds, terpenoids, steroids, alkaloids, etc. This chapter provides an overview of these phytoconstituents frequently involved in the management of lifestyle diseases and the various chemical techniques used for their characterization.
Trema orientale (L.) Blume is an important medicinal plant with multiple applications for treating several disease conditions. This study compiled published data on botanical, traditional uses, phytochemistry, pharmacology, and antimicrobials, coupled with discussing the conservation and domestication potential of T. orientale. Data were sourced from databases such as Google Scholar, PubMed, Scopus, Elsevier Plants of the World Online (Kew Science), Global Biodiversity Information Facility (GBIF), and World Flora Online (WFO), using key search terms: Trema orientale or orientalis, phytochemistry pharmacology, taxonomy, and domestication with Boolean operators to include and exclude articles for the review. The review indicated that molecular studies have shown that T. orientale is closely related to a sister group of Cannabis through plastome phylogenetic evidence which accounts for its transfer from Ulmaceae to the Cannabaceae family. T. orientale is distributed across several African countries and has recently been assessed as the Least Concern by the IUCN Red List of Threatened Species. Nevertheless, deforestation continues to pose an extinction risk to their population. Currently, 31 compounds have been isolated from different parts of T. orientale justifying many traditional uses accredited to it. T. orientale is considered a dose-dependent safe remedy for the treatment of infectious diseases, cancer, cardiovascular diseases and other disease conditions ascribed to it except for its continuous application. This review underscores the domestication potential of T. orientale including evidence of molecular markers, soil seed banks, and promising outcomes of germination experimentations. This, therefore, presents significant gains toward sustainable utilization of Trema orientale.
Pterocaulon genus comprises 26 species, half of them have been phytochemical investigations regarding the chemical composition, and coumarins have been considered the chemotaxonomic markers in the genus. Herein Pterocaulon angustifolium DC (Asteraceae), a native plant from Brazil, is investigated for the first time. Twenty-six compounds were isolated from aerial parts of P. angustifolium DC., being 5 triterpenes, 4 phytosterols, 9 flavonoids, 3 phenolic acids, and 5 coumarins. Moreover, a total of 177 compounds were putatively identified using the dereplication technique by UHPLC-HRMS/MS, more than 50% correspond to flavonoids and coumarins. Although 41 different coumarins have already been reported in Pterocaulon genus, 16 were identified for the first time in this study. Crude ethanolic extract and fractions of P. angustifolium were also biologically investigates, and dichloromethane fraction was the most active fraction in the evaluation of antiproliferative, antioxidant, antimicrobial and cholinesterase inhibitory activities.
Background Bauhinia thonningii is a plant traditionally used against many human diseases such as gastric ulcers,
fever, inflammations, coughs, dysentery, diarrhea, and malaria. In the present investigation, the cytotoxicity of methanol
extract of Bauhinia thonningii leaves (BTL), fractions and the isolated phytoconstituents was determined in a panel
of 9 human cancer cell lines including drug sensitive and multidrug-resistant (MDR) phenotypes. The acute and subchronic
oral toxicity of BTL was investigated as well.
Methods Compounds were isolated using chromatographic techniques while their chemical structures were
determined using spectroscopic methods. The resazurin reduction assay (RRA) was used to evaluate the cytotoxicity
of samples, propidium iodide (PI) for apoptosis, 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolylcarbocyan
ine iodide (JC-1) staining for mitochondrial membrane potential (MMP) analysis, 2´,7´-dichlorodihydrofluoresceine
diacetate (H2DCFH-DA) staining for the quantification of reactive oxygen species (ROS), whereas Caspase Glo assays
were combined by means of flow cytometry. Furthermore, the toxicological investigations were performed as recommended
by the Organization for Economic Cooperation and Development (OECD).
Results The botanicals as well as 6-C-methylquercetin-3,7-dimethyl ether (2), quercetin-3-O-L-rhamnopyranoside (5),
quercetin-3-O-β-glucopyranoside (6), 6,8-C-dimethylkaempferol 3,7-dimethyl ether (7), and 6,8-C-dimethylkaempferol-
3-methyl ether (8) had promising cytotoxic effects in the 9 tested cancer cell lines. The IC50
values below 20 μg/
mL (botanicals) or 10 μM (compounds) on at least 1/9 tested cancer cell lines were considered. The best cytotoxic
effects with IC50
values below 5 μM were achieved with compounds 7 against CEM/ADR5000 leukemia cells
(2.86 μM) and MDA-MB-231-pcDNA breast adenocarcinoma cells (1.93 μM) as well as 8 against CCRF-CEM leukemia
cells (3.03 μM), CEM/ADR5000 cells (2.42 μM), MDA-MB-231-pcDNA (2.34 μM), and HCT116 p53−/− cells (3.41 μM). BTL
and compound 8 induced apoptotic cell death in CCRF-CEM cells through caspase activation, alteration of MMP,
and increased ROS production. BTL did not cause any adverse effects in rats after a single administration at 5000 mg/
kg or a repeated dose of 250 mg/kg body weight (b. w.).
Conclusion Bauhinia thonningii and its constituents are sources of cytotoxic drugs that deserve more in-depth studies
to develop novel antiproliferative phytomedicine to fight cancer including resistant phenotypes.
Background
Bauhinia thonningii is a plant traditionally used against many human diseases such as gastric ulcers, fever, inflammations, coughs, dysentery, diarrhea, and malaria. In the present investigation, the cytotoxicity of methanol extract of Bauhinia thonningii leaves (BTL), fractions and the isolated phytoconstituents was determined in a panel of 9 human cancer cell lines including drug sensitive and multidrug-resistant (MDR) phenotypes. The acute and sub-chronic oral toxicity of BTL was investigated as well.
Methods
Compounds were isolated using chromatographic techniques while their chemical structures were determined using spectroscopic methods. The resazurin reduction assay (RRA) was used to evaluate the cytotoxicity of samples, propidium iodide (PI) for apoptosis, 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining for mitochondrial membrane potential (MMP) analysis, 2´,7´-dichlorodihydrofluoresceine diacetate (H2DCFH-DA) staining for the quantification of reactive oxygen species (ROS), whereas Caspase Glo assays were combined by means of flow cytometry. Furthermore, the toxicological investigations were performed as recommended by the Organization for Economic Cooperation and Development (OECD).
Results
The botanicals as well as 6-C-methylquercetin-3,7-dimethyl ether (2), quercetin-3-O-L-rhamnopyranoside (5), quercetin-3-O-β-glucopyranoside (6), 6,8-C-dimethylkaempferol 3,7-dimethyl ether (7), and 6,8-C-dimethylkaempferol-3-methyl ether (8) had promising cytotoxic effects in the 9 tested cancer cell lines. The IC50 values below 20 µg/mL (botanicals) or 10 µM (compounds) on at least 1/9 tested cancer cell lines were considered. The best cytotoxic effects with IC50 values below 5 µM were achieved with compounds 7 against CEM/ADR5000 leukemia cells (2.86 µM) and MDA-MB-231-pcDNA breast adenocarcinoma cells (1.93 µM) as well as 8 against CCRF-CEM leukemia cells (3.03 µM), CEM/ADR5000 cells (2.42 µM), MDA-MB-231-pcDNA (2.34 µM), and HCT116 p53−/− cells (3.41 µM). BTL and compound 8 induced apoptotic cell death in CCRF-CEM cells through caspase activation, alteration of MMP, and increased ROS production. BTL did not cause any adverse effects in rats after a single administration at 5000 mg/kg or a repeated dose of 250 mg/kg body weight (b. w.).
Conclusion
Bauhinia thonningii and its constituents are sources of cytotoxic drugs that deserve more in-depth studies to develop novel antiproliferative phytomedicine to fight cancer including resistant phenotypes.
A complete assignment of the ¹H and ¹³C n.m.r. signals of the lichen triterpenoid 12α-acetoxyfern-9(11)-en-3 β-ol (lb) has been achieved by using one- and two-dimensional n.m.r. techniques. Evidence in support of one of two recently advanced assignments of the methyl group resonances of fern-9(11)-en-3-β-ol (1a) is presented.
Chemical shift assignments are reported for some hopane triterpenoids variously oxygenated at C3, C6, C7, C15, C22 and/or C24. Substituent group effects are compared and correlated with a local symmetry axis. Revisions to a recently reported interpretation of the ¹³C n.m.r. spectrum of 7β-acetoxyhopan-22-ol (1c) are described.
Three new hopane triterpenes have been isolated from lichens of the family Physciaceae. Two of the triterpenes, 22-hydroxyhopan-6-one (2) and 6 α-acetoxyhopan-22-ol (1b), have been characterized previously but their natural occurrence is reported for the first time, while a new triterpene acid [ aipolic acid (1c)], was isolated and characterized as the corresponding methyl ester. One- and two-dimensional ¹H-¹H and ¹³C-lH correlated n.m.r. studies have revealed methyl aipolate to be methyl 6#945;-acetoxy-22-hydroxyhopan-25-oate (1d).
The known triterpenes ursonic acid, oleanonic acid, ursolic acid, oleanolic acid and 24-hydroxy-3-oxoolean-12-en-28-oic acid occur in Lantana tiliaefolia Cham., together with a new triterpene,24-hydroxy-3-oxours-12-en-28-oic acid. A detailed ¹³C n.m.r. study has been made of a number of olean-12-enes and urs-12-enes, and the ¹H n.m.r. signals from the secondary methyl groups in urs-12-enes have been investigated. N.m.r. evidence shows significant conformational differences in ring A between a number of 3-oxo derivatives that differ in their ring A substituents. Methyl ursonate and methyl oleanonate have been separated on columns of Spherosorb A5Y alumina.
The triterpenes 20α-acetoxyhopane-6α, 22-diol, 16β-acetoxyhopane-6α,22-diol, 6α-acetoxyhopane-16β,22-diol and 6α,l6β -diacetoxyhopan-22-ol have been isolated from chemical strains of Physcia aipolia. The structure of these triterpenes followed primarily from the ¹³C n.m.r. spectra.
Three triterpenoid prosapogenins tentatively named CP0 (I), CP2a (VI) and CP3a(VIII) have been isolated from the alkaline hydrolysate of the crude saponin obtained from the root of Clematis chinensis Osbeck. On the basis of chemical and physicochemical evidence, they were characterized as follows: I, hederagenin 23-O-α-l-arabinopyranoside; VI, hederagenin 23-O-β-d-glucopyranoside; VIII, olean-12-ene-28-oic acid-3β,24-diol (4-epihederagenin) 3-O-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside. I and VI are the first examples of 23-O-glycosides of oleanane-type triterpenes to be isolated from nature. Six less polar genuine saponins were isolated and they appeared to be identical with prosapogenins CP4, CP6, CP7, CP8, CP9 and CP10,1,4) on the basis of the results of high performance thin-layer chromatography (HPTLC). © 1982, The Pharmaceutical Society of Japan. All rights reserved.
The phase-sensitive two-dimensional (2D) 13C-1H heteronuclear correlated and double quantum-filtered COSY NMR spectra of 7.beta.-acetoxyhopan-22-ol (I) and 2.alpha.,3.beta.,22.alpha.-triacetoxystictane (II) were recorded at resoln. sufficient for the complete assignment of their 1H resonances. Revisions to some of the methylene 1H resonances of 7.beta.-acetoxyhopan-22-ol proposed elsewhere are discussed, and assignments for a series of flavicene and stictane triterpenes are presented. 2D NMR anal. of a new triterpene isolated from Pseudocyphellaria coronata revealed it to be 22.alpha.-hydroxystictano-252,3.beta.-lactone (III).
Since the late 1950’s when proton n. m. r. spectroscopy was first used in organic natural products studies the technique has increasingly contributed to the rapid advancement of this important area of chemistry. Although the potential utility of 13C n. m. r. was recognized very early, essentially no application of 13C n. m. r. appeared in the literature prior to 1966 and 95% of the existing data are less than five years old. The initially slow growth had its cause in inadequate instrumentation, insufficient sensitivity being the main obstacle. This situation drastically changed with the advent and commercial availability of broadband excitation and Fourier transform methods, giving natural-abundance 13C n. m. r. and its numerous chemical applications a tremendous impetus. Today 13C spectra can be recorded on sample quantities down to the submilligram level, which until recently even withstood proton n. m. r.
The molecular geometry of asiaticoside (1 ), a trisaccharide triterpene isolated from Centella asiatica, has been determined by a single-crystal X-ray analysis. The glycoside, C48H78O19, is prismatic with space group monoclinic, C2 and lattice constants a = 41.46 (1), 0 = 7.563 (4), c = 17.988 (5). Å, β = 99.66(5)°, cell volume V = 5602.3 Å3, and Z = 4. Diffractometer intensity measurements were made with Cu-kα radiation and least-squares adjustment of the atomic parameters converged to a final R value of 0.073. 13C N.m.r. and f.a.b.-m.s. are satisfactorily interpreted within terms of the structure.
Applications of inverse-detected 2D nmr methods are reviewed. Sequences presently available for direct (one-bond) heteronuclear correlation via 1J(XH) (HMQC and others) are discussed individually followed by examples of applications to natural products presented by class. Correlations of heteronuclear pairs other than H-1-C-13 and H-1-N-15 are briefly considered. Optimization of parameters necessary in the acquisition of inverse-detected heteronuclear chemical shift correlation data are considered, followed by an illustration using the degradation product of 1-bromomaaliol. Methods for performing HMQC-COSY (RELAY) and HMQC-TOCSY experiments are considered with examples. Various ways of utilizing HMQC-TOCSY data are discussed followed by an illustration of the assembly of the protonated portion of the carbon skeleton of the degradation product of 1-bromomaaliol by varying the mixing times in a series of HMQC-TOCSY experiments. Long-range proton-detected heteronuclear chemical shift correlation experiments (HMBC) are presented with extensive examples of the application of these experiments to a diverse assortment of natural products, which are presented by class of compounds. A practical example of the application of the HMBC experiment to the degradation product of 1-bromomaaliol follows. The relatively new HMQC-NOESY experiment is presented followed by a discussion of the relatively few examples of this experiment presently contained in the literature. Finally, examples of proton-detected one-dimensional analogues of 2D nmr experiments are described; these include SELINCOR, selective one-dimensional HMQC-TOCSY, and SIMBA (selective inverse multiple bond analysis).
Further study on the chemical constituents of the Abrus species resulted in the isolation of a new sapogenol, abrisapogenol J (1), from the methanolysate of the seeds for Abrus precatorius L., together with sophoradiol (4), its 22-O-acetate (2) and hederagenin methyl ester (5). The structure of 1 has been elucidated to be 3β, 22β-dihydroxy-11-oxoolean-13(18)-ene by the use of hetero unclear multiple bonds correlation (HMBC) spectroscopy. In addition, various compounds, trimethyl tryptophan dipolar ion (3), kaikasaponin III methyl ester (6), abrine (7), abrusin (8) and its 2"-O-apioside (9) were obtained from the methanolic extract.
Two new triterpenoid sulfates were isolated from the fresh leaf blades of Scheffera octophylla (Araliaceae). On the basis of results of spectral and chemical investigations, their structures were characterized as free forms of 3-epi-betulinic acid 3-O-sulfate and betulinic acid 3-O-sulfate.
Further investigation of the chemical constituents of the leaves of Acanthopanax senticosus HARMS. resulted in the isolation of five new triterpenoid saponins, named ciwujianosides A1 (1), A2 (2), A3 (3), D3(4) and A4 (5). The structures of these saponins were elucidated as follows : 1, 3-O-β-glucopyranosyl-(1→2)-α-arabinopyranosyloleanolic acid 28-O-α-rhamnopyranosyl-(1→4)-β-glucopyranosyl-(1→6)-β-glucopyranosyl ester; 2, 3-O-β-glucopyranosyl-(1→2)-α-arabinopyranosyl-30-norolean-12, 20(29)-dien-28-oic acid 28-O-α-rhamnopyranosyl-(1→4)-β-glucopyranosyl-(1→6)-β-glucopyranosyl ester; 3, 3-O-α-rhamnopyranosyl-(1→2)-α-arabinopyranosylmesembryanthemoidigenic acid 28-O-α-rhamnopyranosyl-(1→4)-β-glucopyranosyl-(1→6)-β-glucopyranosyl ester; 4, 3-O-α-arabinopyranosylmesembryanthemoidigenic acid 28-O-α-rhamnopyranosyl-(1→4)-6-O-acetyl-β-glucopyranosyl-(1→6)-β-glucopyranosyl ester; 5, 3-O-β-glucopyranosyl-(1→2)-α-arabinopyranosylmesembryanthemoidigenic acid 28-O-α-rhamnopyranosyl-(1→4)-6-O-acetyl-β-glucopyranosyl-(1→6)-β-glucopyanosyl ester.
The structures of lobatosides B, E, F and G, the dicrotalic acid esters of bayogenin bisdesmosides isolated from the harb of Actinostemma lobatum MAXIM. (Cucurbitaceae), were determined on the basis of chemical and spectral evidence.Lobatoside B is the dicrotalic acid (3-hydroxy-3-methylglutaric acid) ester of 3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl]bayogenin 28-[α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] ester. Dicrotalic acid is linked at one end to the C6-hydroxyl group of the terminal β-D-glucopyranosyl group in the C3-linked sugar moiety, and at the other end to the C4-hydroxyl group of the α-L-rhamnopyranosyl group in the ester-linked sugar moiety to form a macrocyclic structure (cyclic bisdesmoside).Lobatosides E, F and G are cyclic bisdesmosides of bayogenin similar to lobatoside B, but different in the numbers and species of the component sugars and positions of the ester linkages of the dicrotalic acid.
Nine novel triterpenoid saponins, named crocosmiosides A-I, were isolated from the corms of montbretia (Crocosmia crocosmiiflora N. E. BR., Iridaceae). Among those saponins, the structures of crocosmiosides A (1), B (2) and H (3) were determined on the basis of spectral and chemical evidence. They are unique acylated saponins which have 2, 9, 16-trihydroxypalmitic acid glycoside as the acyl moiety, and their structures were elucidated as polygalacic acid-3-{α-L-arabinopyranosyl-(1→6)-β-D-glucopyranosido}-28-{2-O-[β-D-apio-D-furanosyl-(1→4)-β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl]-4-O-(9-hydroxy-16-α-L-rhamnopyranosyloxy-2-β-D-xylopyranosyloxyhexadecanoyl)-β-D-fucopyranoside} (1), polygalacic acid-3-{α-L-arabinopyranosyl-(1→6)-β-D-glucopyranosido}-28-{2-O-[β-D-apio-D-furanosyl-(1→4)-β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl]-4-O-(9, 16-dihydroxy-2-β-D-xylopyranosyloxyhexadecanoyl)-β-D-fucopyranoside} (2) and polygalacic acid-3-{α-L-arabinopyranosyl-(1→6)-β-D-glucopyranosido}-28-{2-O-[β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl]-4-O-(9-hydroxy-16-α-L-rhamnopyranosyloxy-2-β-D-xylopyranosyloxyhexadecanoyl)-β-D-fucopyranoside} (3), respectively.
Two new triterpenoid glycosides, 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosiduronic acids (2 and 3) of 3β, 22β-dihydroxyolean-12-en-29-oic acid and 3β, 21β, 22β-trihydroxyolean-12-en-29-oic acid, along with a known glycoside, kaikasaponin III (1), were isolated from the bark of Dalbergia hupeana HANCE. Their structures were determined by chemical and spectral methods.
Two new triterpenoid glycosides were isolated (one of them as the methyl ester) as major components from leaves of Ilex chinensis SIMS (Aquifoliaceae). The structures of these glycosides, termed ilexoside A (1) and ilexoside B methyl ester (2a), have been established to be 3β-Ο (β-D-xylopyranosyl) siaresinolic acid and 3β-Ο (β-D-xylopyranosyl) pomolic acid methyl ester, respectively, based on chemical and spectral evidence. High-resolution 13C-nuclear magnetic resonance data for the methyl ester of 1 (1a) and 2a are also reported.
Eight triterpenoid hydrocarbons were characterized from the fresh leaves of Cheiropleuria bicuspis. They consist of hop-22(29)-ene, neohop-13(18)-ene, fern-7-ene, (18R)-dammara-13(17), 21-diene, eupha-7, 21-diene, 13α(H)-malabaricatriene, γ-polypodatetraene and squalene, all of which have different carbon skeletons, A new triterpenoid alcohol was isolated and established as 1α, 11α, 30-trihydroxyhopane. We also detected friedelin, hydroxyhopane, dryocrassol, lupeol, fernenol, 1α, 11α, 22-trihydroxyhopane, a mixture of sterols and a mixture of fatty acid esters of cycloartanoids, methylsterols and sterols. These findings suggest that Cheiropleuria bicuspis is related to Microsorium (Polypodiaceae), but are nevertheless consistent with the independency of Cheiropleuriaceae.
No diterpene glycoside was isolated from the roots of Rubus suavissimus S. LEE, in contrast to its leaves, which taste sweet and contain a large amount of the sweet diterpene glucoside named rubusoside. Instead, a new 28-β-gluchopyranosyl ester of 2α, 3β, 19α-trihydroxyurs-12-ene-23, 28-dioic acid named suavissimoside F1 was isolated from the roots of this plant, along with niga-ichigoside F1 (28-β-glucopyranosyl ester of 19α-hydroxyasiatic acid) which has already been obtained from leaves of other Rubus spp.
The structures of six new arborane type triterpenoids, rubiarbonols A, B, C, D, E, and F, from Rubia plants were determined as 3β, 7β, 19α, 28-tetrahydroxyarbor-9(11)-ene, 3β, 7β, 19α-trihydroxyarbor-9(11)-ene, 2α-acetoxy-3β, 7β, 19α-trihydroxyarbor-9(11)-ene, 3β-acetoxy-2α, 7β, 19α-trihydroxyarbor-9(11)-ene, 2α, 3β, 7β, 19α-tetrahydroxyarbor-9(11)-ene, and 2α, 3β, 7β, 19α, 28-pentahydroxyarbor-9(11)-ene respectively by various spectroscopic methods.
The powder coating of a bamboo, Lingnania chungii MCCLURE (=Bambusa chungii) was found to be a rich source of the 3-oxo pentacyclic triterpenes (25% on the recovery basis by chromatography on silica gel) which contained friedelin, arborinone and glutinone as the major components accompanied by minor amounts of α- and β-amyrenones. A simple procedure for isolation of friedelin is described. All proton and carbon-13 nuclear magnetic resonance signals for arborinone, friedelin and glutinone were assigned.
From the fresh rhizomes of the ferns, Microsorium brachylepis and M. normale (Polypodiaceae) we isolated new triterpenoid acids, fern-7-, fern-8- and fern-9(11)-en-28-oic acids, and adian-5-en-28-oic acid as their methyl esters. Their structrues were determiend by spectral analysis and chemical correlations.
A new tetrahydroxy triterpene acid, named clethric acid (I), in addition to barbinervicand rotundic-acids, has been isolated from the leaves of Clethra barbinervis SIEB. et ZUCC and clethric acid was elucidated as 3α, 19α, 23, 24-tetrahydroxyurs-12-en-28-oic acid by the chemical and spectral evidences. The 13C-nuclear magnetic resonance spectra of the methylates and acetyl methylates of clethric acid, pomolic acid, rotundic acid and barbinervic acid were studied.
Seven oleanene-sapogenols (1-7) were obtained from the methanolysate of the crude saponin in Puerariae Radix. Four of them, sapogenols 1-4, were identical with sophoradiol, cantoniensistriol, and soyasapogenols B and A. The structures of three new sapogenols (5-7), named kudzusapogenols C, A and B methyl ester, were deduced by spectroscopic means.
In the course of studies on the metabolism of saikosaponins, which are the main constituents of Bupleurum falcatum L., five new compounds derived from saikosaponins a, c and d were isolated after incubation with acid and snail enzyme. On incubation of saikosaponins a and c at 60°C in a 1 N sulfuric acid-dioxane solution, saikosaponins g and i possessing a homoannular diene moiety at C-9 (11), 12 were isolated, and their structures were elucidated as 3β, 16β, 23, 28-tetrahydroxyoleana-9 (11), 12-diene 3-O-β-D-glucopyranosyl-(1→3)-β-D-fucopyranoside and 3β, 16β, 28-trihydroxyoleana-9 (11), 12-diene 3-O-β-D-glucopyranosyl-(1→6)-[α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranoside, respectively. Furthermore, on incubation of saikosaponins b1, g and b2 with snail enzyme for 12h at 37°C, prosaikogenins A, H, and D were formed ; they were identified as the 3-β-D-fucopyranosides of saikogenins A, H and D.
Four new triterpenoid saponins (wistariasaponins A, B1, B 2 and C) were isolated as methyl ester forms from the knots of Wistaria brachybotrys (Leguminosae), and their structures were characterized as 3-O-[α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranosyl(1→2) -β-D-glucuronopyranosyl]wistariasapogenol A, 3-O[α-L- rhamnopyranosyl(1→2)-β-D- xylopyranosyl(1→2)-β-D- glucuronopyranosyl]wistariasapogenol B, 3-O-[α-L-rhamnopyranosyl(1→2) -β-D-galactopyr- anosyl(1→2)-β-D-glucuronopyranosyl] wistariasapogeno] B and 3-O-[α-L-rhamnopyranosyl(1→2)-β-D- xylopyranosyl-(1→2)-β-D-glucuronopyranosyl]soyasapogenol B, respectively, on the basis of chemical and physicochemical evidence. The inhibitory effects of these saponins and sapogenols on Epstein-Barr virus activation induced by a tumor promoter were also tested for the primary screening of anti-tumor promoting activities.
Two new triterpene acids were isolated from the plant Cornulaca monacantha DEL. The first acid was assigned the structure 3β, 6α-dihydroxyolean-12-en-27-oic acid I and was given the trivial name manevalic acid. The other compound was assigned the structure 3β, 6α-dihydroxyolean-12-en-27, 28-dioic acid II and named azizic acid. These assignments were based on spectral and chemical studies. The chemical correlation between manevalic acid and the known triterpene astilbic acid, 3β, 6β-dihydroxyolean-12-en-27-oic acid, was established through oxidation of their methyl esters to methyl 3, 6-dioxoolean-12-en-27-oate IC.
Seven triterpenoidal saponins, onjisaponins A, B, C, D, E, F, and G, were isolated from the roots of Polygala tenuifolia WILLDENOW. Among these saponins, the structures of onjisaponins G (1) and F (2) were determined on the basis of spectral and chemical evidence as presenegenin-(3)-β-D-glucopyranosido-(28)-2-O-{[β-D-apio-D-furanosyl (1→3)]-[β-D-xylopyranosyl (1→4)]-α-L-rhamnopyranosyl}-4-O-(3', 4', 5'-trimethoxycinnamoyl)-β-D-fucopyranoside and presenegenin-(3)-β-D-glucopyranosido-(28)-2-O-{[β-D-apio-D-furanosyl-(1→3)] [α-L-arabinopyranosyl (1→3)-β-D-xylopyranosyl (1→4)]-α-L-rhamnopyranosyl}-4-O-(3', 4', 5'-trimethoxycinnamoyl)-β-D-fucopyranoside, respectively.
Two new triglycosides of oleanane-type triterpenes, rotundioside E (3) and F (1), isolated from the leaves of Bupleurum rotundifolium L. were identified as 16α, 28-dihydroxyoleana-11, 13 (18)-dien-3β-yl α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-β-D-fucopyranoside (3) and 13β, 28-epoxy-16α-hydroxyoleana-11-en-3β-yl α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-β-D-fucopyranoside (1), respectively, on the basis of chemical and spectroscopic evidence.
From the roots of Rubia cordifolia var. pratensis, three new triterpenoids named rubiprasins A, B and C have been isolated and their structures were determined as 3β-acetoxyoleanane-13β, 15α-diol-12-one, 3β-acetoxyoleanace-13β-ol-12-one and 3β-acetoxyl-19α-hydroxyolean-12-en-28-oic acid respectively by various chemical and spectroscopic methods including 1H-1H COSY, 1H-13C COSY and X-ray diffractions.
Two new triterpenoid hydrocarbons were isolated from the rhizomes of Davallia mariesii MOORE, together with neohop-13(18)-ene, hop-21-ene, hop-17(21)-ene, hydroxyhopane, cyclolaudenol and cyclobalanol. On the other hand, fern-9(11)-ene, ferna-7, 9(11)-diene, fern-7-ene, hop-22(29)-ene, hydroxyhopane and dryocrassol were isolated from the leaves of the same fern. The structures of two new compounds, hop-16-ene (1) and isohop-22(29)-ene (2), were elucidated on the basis of spectral data and chemical correlations with known compound.
Four new oleanene sapogenols having 22-oxo group were obtained from the methanolysate of the crude glycosidic fraction in Sophorae Subprostratae Radix, the root of Sophora subprostrate CHUN et T. CHEN. Also, twelve known sapogenols were isolated from the same methanylsate.
Grains of Quinoa, Chenopodium quinoa have been used as a staple food in the Andes, South America. In a continuing study on saponin constituents of this plant, seven oleanane saponins were isolated from brans of the grains. Two of them were identified as known saponins of oleanolic acid, chikusetsusaponin IVa (10) from rhizomes of Panax spp. and quinoside D (12) from seeds of this plant, respectively. The other five compounds (7, 8, 9, 11 and 13) are new saponins, being designated as quinoa-saponins-6-10. The structures of these saponins were elucidated as follows : 7, 8 and 9, 3-O-[β-glucopyranosyl(1→2)-β-glucopyranosyl(1→3)-α-arabinopyranoside]-28-O-β-glucopyranoside of 30-O-methyl spergulagenate, oleanolic acid and phytolaccagenic acid, respectively; 11, hederagenin 3-O-β-glucuronide-28-O-β-glucopyranoside; and 13; hederagenin 3-O-β-xylopyranosyl(1→3)-β-glucuronide-28-O-β-glucopyranoside.
Three sulfated tetraglycosides of oleane-type triterpenoids, rotundiosides A (1), B (2) and C (3), isolated from the leaves of Bupleurum rotundifolium L., were characterized as the 3β-sulfate ester of 16α-hydroxyolean-12-ene-28-oyl β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl (1→2)-β-D-glucopyranosyl (1→6)-β-D-glucopyranoside, the 3β-sulfate ester of olean-12-ene-28-oyl β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl (1→6)-β-D-glucopyranoside and the 3β-sulfate ester of olean-12-ene-28-oyl β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl (1→2)-β-D-glucopyranosyl (1→2)-β-D-glucopyranoside, respectively, on the basis of chemical and spectroscopic evidence.
Triterpenoids isolated and characterized from various sources are reviewed. The newer techniques used in their isolation and structure elucidation, the newer skeleton triterpenoids characterized, chemical modifications and synthetic studies reported are discussed. A compilation of the triterpenoids isolated during the period 1982-1989 along with their occurrence, available physical data, spectroscopy and X-ray analysis used for their characterization, is included. The biological activities of the triterpenoids are also described.
A significantly increased resolution in the proton-coupled 13C NMR spectrum of MeI was achieved by 2-dimensional J spectroscopy. [on SciFinder (R)]
The possibilities for the extension of spectroscopy to two dimensions are discussed. Applications to nuclear magnetic resonance are described. The basic theory of two‐dimensional spectroscopy is developed. Numerous possible applications are mentioned and some of them treated in detail, including the elucidation of energy level diagrams, the observation of multiple quantum transitions, and the recording of high‐resolution spectra in inhomogenous magnetic fields. Experimental results are presented for some simple spin systems.
Migrated gammacerane triterpenoids, named pichierenyl acetate (1) and isopichierenyl acetate (2), were isolated from the fresh roots of Picris hieracioides subsp. japonica, Compositae. By spectral and chemical methods, the structures of 1 and 2 were established as the members of migrated gammacerane series with a Δ9(11) and a Δ8 double bond respectively.
New triterpenoids, gammacer-16-en-3β-yl acetate (3), gammacer-16-en-3β-ol (4) and gammacer-16-en-3α-ol (5) were isolated from the fresh roots of Picris hieracioides subsp. japonica, Compositae. Their structures were established by chemical and spectral methods. X-ray crystallographic study of the corresponding ketone (6) confirmed the structures of 3, 4 and 5.
Trichadenic acid B, isolated first from Hydrocarpuzoctandra and its acetate from Trichadeniazeylanica (Flacourtiaceae), was also obtained from the stem bark of Phyllanthusflexuosus (Euphorbiaceae) and the structure was revised as 3β-hydroxy-D:A-friedooleanan-27-oic acid, which have revealed the coexistence of S and F forms in the X-ray analysis.
The structure of kairateno1 (1a), the first representative of a new class of migrated gammacerane triterpenoid, has been established on the basis of spectral evidence and chemical correlations.