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ABSTRACT: Eight flavonoids were isolated from Sophora flavescens. Among them, three prenylflavanones: (2S)-6[2(3-hydroxyisopropyl)-5-methyl-4-hexenyl]-5-methoxy-7,2', 4'-trihydroxyflavanone (1), (2S)-5, 4'-dimethoxy-8-lavandulyl-7, 2'-dihydroxy flavanone (2) and (2S)-8-(5-hydroxy-2-isopropenyl-5-methylhexyl)-7-methoxy-5,2', 4'-trihydroxyflavanone (3) are new compounds. Their chemical structures were determined by spectral methods including 2D NMR.
Magnetic Resonance in Chemistry 07/2008; 46(9):903-6. · 1.44 Impact Factor
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ABSTRACT: A high-performance liquid chromatography-diode array UV detection-electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS) method was developed and validated for the simultaneous analysis of seven major constituents in Cortex Fraxini, including esculin, esculetin, fraxetin, fraxin, escuside, oleuropein and ligustroside. The contents of the seven constituents were determined by using HPLC-DAD, and the chemical structures of these constituents were identified by using HPLC-DAD-ESI-MS method. The separation was performed on an Agilent Zorbax SB-C18 column (250 mm x 4.6 mm i.d., 5 microm) with gradient elution of acetonitrile and 0.3% aqueous acetic acid within 40 min. Detection was performed at 254 nm. The calibration curves showed good linearity (r2>0.9992). The limits of detection (LOD) ranged from 1.07 to 3.19 ng/ml and limits of quantification (LOQ) ranged from 2.79 to 12.75 ng/ml, respectively. The intra- and inter-day precision was less than 5% and the accuracy was ranging from 96.49% to 103.55%. The recovery of the assay was in the range of 97.61-104.36%. The method was successfully applied to the quantification of the seven constituents in different samples of Cortex Fraxini. The results indicated that the developed method could be considered to be a simple, rapid and reliable method for the quality evaluation of Cortex Fraxini.
Journal of Pharmaceutical and Biomedical Analysis 05/2008; 47(1):39-46. · 2.97 Impact Factor
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Man Xu,
Hui Guo,
Jian Han,
Shi-feng Sun,
Ai-hua Liu,
Bao-rong Wang, Xiao-chi Ma,
Peng Liu,
Xue Qiao,
Zi-chuan Zhang,
De-an Guo
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ABSTRACT: This study was conducted to compare the in vivo metabolites of salvianolic acid B (Sal B) between normal rats and antibiotic-treated rats and to clarify the role of intestinal bacteria on the absorption, metabolism and excretion of Sal B. A valid method using LC-MS(n) analysis was established for identification of rat biliary and fecal metabolites. And isolation of normal rat urinary metabolites by repeated column chromatography was applied in this study. Four biliary metabolites and five fecal metabolites in normal rats were identified on the basis of their MS(n) fragmentation patterns. Meanwhile, two normal rat urinary metabolites were firstly identified on the basis of their NMR and MS data. In contrast, no metabolites were detected in antibiotic-treated rat urine and bile, while the prototype of Sal B was found in antibiotic-treated rat feces. The differences of in vivo metabolites between normal rats and antibiotic-treated rats were proposed for the first time. Furthermore, it was indicated that the intestinal bacteria showed an important role on the absorption, metabolism and excretion of Sal B. This investigation provided scientific evidence to infer the active principles responsible for the pharmacological effects of Sal B.
Journal of Chromatography B 11/2007; 858(1-2):184-98. · 2.89 Impact Factor
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ABSTRACT: Five germacrane-type sesquiterpene alcohols obtained from curdione (1) by microbial biotransformation were isolated. Their structures were characterized as (2R)-2beta-hydroxycurdione (2), 1alpha, 10beta-epoxy-11-hydroxycurdione (3), (2S)-2alpha, 11-dihydroxycurdione (4), 11,15-dihydroxycurdione (5) and (3R)-3alpha-hydroxycurdione (6) based on the extensive NMR studies. Among them, 4, 5 and 6 are new compounds.
Magnetic Resonance in Chemistry 02/2007; 45(1):90-2. · 1.44 Impact Factor
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ABSTRACT: Three new cyclolanostane triterpenoids, 1–3, were isolated from the EtOH extract of the stems of Kadsura heteroclita. Their structures and configurations were determined by extensive 1D- and 2D-NMR spectroscopy, high-resolution mass spectrometry (HR-MS), and circular dichroism (CD) spectroscopy. The three new compounds are likely to be artificial products formed during the extraction process, and might be derived from schisanlactone E (4) and two related double-bond isomers, respectively.
Helvetica Chimica Acta 09/2006; 89(9):1888 - 1893. · 1.48 Impact Factor
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ABSTRACT: A new cyclodipeptide named as cordycedipeptide A, a new natural compound and two known compound were isolated from the culture liquid of Cordyceps sinensis (BERK.) SACC. Their structures were elucidated as 3-acetamino-6-isobutyl-2,5-dioxopiperazine (1), 3-isopropyl-6-isobutyl-2,5-dioxopiperazine (2) and 3,6-di(4-hydroxy)benzyl-2,5-dioxopiperazine (3) by 1D and 2D-NMR techniques. The cytotoxic assay showed compound 1 had the cytotoxic activities to L-929, A375, and Hela.
CHEMICAL & PHARMACEUTICAL BULLETIN 06/2005; 53(5):582-3. · 1.59 Impact Factor
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ABSTRACT: Twenty strains of filamentous fungi (from nine genera) and four species of bacteria were screened for their capabilities to transform bufadienolides. The highly stereo- and regiospecific isomerization and dehydrogenation of three major bufadienolides (resibufogenin, cinobufagin and bufalin) at 3-OH by Fusarium solani AS 3.1829 were reported. Three major transformed products were obtained and their structures were identified as 3-epi-resibufogenin (1a), 3-epi-bufalin (2a), 3-keto-cinobufagin (3a), respectively, on the basis of their spectral data. The reaction kinetics and the effects of pH, substrate concentration and incubation phase on the biotransformation were also investigated.
Enzyme and Microbial Technology.
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ABSTRACT: The capabilities of twenty strains of filamentous fungi (from 9 genera) to transform deoxyandrographolide (1) were screened. And eleven derivatives of 1 transformed by Cunninghamella echinulata AS 3.3400 were isolated. Their chemical structures were identified by spectral methods including 2D NMR. Among them, 3-oxo-7α-hydroxy-14-deoxyandrographolide (2), 3-oxo-8β,17α-epoxy-14-deoxyandrographolide (3), 8α-formyl-14-deoxyandrographolide (4), 8β-methoxyl-17α-hydroxyl-14-deoxyandro-grapholide (5) and 3α,17,19-trihydroxyl-7,13-ent-labdadien-15,16-olide (6), are new compounds. And their structure–activity relationships (SAR) were also discussed.Graphical abstractResearch highlights▶ Eleven transformed products from biotransformation of deoxyandrographolide by C. echinulata. And Five of them were novel compounds. ▶ The structure-activity relationships (SAR) of bioconversion products and proposed biosynthetic pathways were listed. ▶ Hydroxylation was the main biotransformation reaction which providing more functional hydroxyl groups for semi-synthesis of ester derivatives.
Journal of Molecular Catalysis B Enzymatic 68(2):187-191. · 2.73 Impact Factor
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ABSTRACT: Twenty strains of filamentous fungi (from nine genera) and four species of bacteria were screened for their capabilities to transform dehydrocostuslactone (1) and costunolide (10). Stereo- and region-specific hydroxylation, epoxidation and hydrogenation reactions of the substrates by Mucor polymorphosporus AS 3.3443 and Aspergillus candidus CICC 2360 were reported. Twelve transformed products were obtained and their structures were identified on the basis of their spectral data. Among them, 10α,14β-epoxy-11α,13-dihydrodehydrocostuslactone and 10α,14-dihydroxy-11α,13-dihydrodehydrocostuslactone are new compounds. The biotransformation kinetics were also investigated.
Enzyme and Microbial Technology 40(5):1013-1019. · 2.37 Impact Factor
