Francesco Cafieri’s research while affiliated with University of Naples Federico II and other places

... (1-4) Compounds 1 and 2 were obtained separately, although the separation by HPLC using an ODS column with aqueous methanol was incomplete and provided a partial mixture. The comparison of 1 H-and 13 C-NMR data with those reported in the literature revealed that 1 and 2 were isoscalarafuran A and furoscalarol, respectively ( Figure 1) [3,27]. ...

Reference:

Cytotoxic Furan- and Pyrrole-Containing Scalarane Sesterterpenoids Isolated from the Sponge Scalarispongia sp

... Endoperoxides are routinely prepared in the laboratory by the action of singlet oxygen on cyclic conjugated dienes. Hence, when the endoperoxides 102-106 were isolated from Tethya aurantia [67] and 102, 107 and 108 from Axinella cannabina [68], it was suspected that they might be artifacts. However, such epidioxides continue to be isolated even when extreme care is taken to prevent their possible formation during extraction and isolation procedure. ...

Reference:

Sterol Ring System Oxidation Pattern in Marine Sponges

... (Table 9; [37,38] Tables S3 and S4), consistent with a molecular formula of C21H34O3. This is consistent with the known furanolactone, plakortone B (2) ( Figure 2B) [34,35]. Due to insufficient material, the 1H and 13C NMR of plakortone B (2) were not determined. ...

Reference:

Bioactive Compounds Isolated from a Marine Sponge Selectively Inhibit Neisseria gonorrhoeae

... 6-Bromo-5-hydroxy-3-indolecarboxyaldehyde (50) along with two other brominated indoles 6-bromo-3-indolecarboxyaldehyde (51) and 3-bromoindole (52) (Figure 7) were discovered in the Caribbean sponge Oceanapia bartschi by Fattorusso's group [18]. Their structurally related non-brominated indole 3-formylindole (53) was disclosed in the Tha sponge O. sagittaria [8]. ...

Reference:

Secondary Metabolites from Marine Sponges of the Genus Oceanapia: Chemistry and Biological Activities

... The additional NOESY interactions, among H-6α, Η-12 and Η3-16, and between the latter and H-9α, as well as the correlations of H-8 with H-5β, H-6β, H-9β, H-10β and H-13, and of H-13 with H-10β, established the uncommon cis-fusion of the two cyclohexane rings, previously reported for coronone [24]. Moreover, the β-equatorial orientation of Η3-15 was evident from its synchronous NOEs observed with H-12 and H-13, thus permitting the assignment of the relative configuration of debromosphaerol (7). ...

Reference:

Halogenated Diterpenes with In Vitro Antitumor Activity from the Red Alga Sphaerococcus coronopifolius

... Iodination occurs more frequently in brown algae metabolites, but only less than 1% of secondary metabolites from brown algae contain bromine or chlorine in contrast with as much as 90% and 7% of red and green algal compounds, respectively [1]. In our continuing investigation aimed at the bioactivity screening and isolation of bioactive metabolites from the Greek seas, eight new structurally diverse halogenated diterpenes (1)(2)(3)(4)(5)(6)(7)(8) were isolated from the red alga S. coronopifolius. Their structures and relative configurations were determined on the basis of their spectroscopic data (mainly NMR and MS). ...

Reference:

Halogenated Diterpenes with In Vitro Antitumor Activity from the Red Alga Sphaerococcus coronopifolius

... A population of this alga previously collected in Liapades Bay at Corfu island afforded three structurally unique diterpenes, including spirosphaerol, anthrasphaerol and corfusphaeroxide [31]. Herein, we report the isolation and structure elucidation of eight new diterpene alcohols (1-8) (Figure 1) from another population collected later from another site in the Ionian Sea, including (i) four tetracyclic halogenated diterpenes, namely iodocoronol (1), the 14-iodo-substituted derivative of coronopifoliol [13], bromocoronol (2), the corresponding 14-bromo-substituted analogue, bromotetrasphaereniol (3), the Δ 3,18 unsaturated 14-deoxy derivative of bromotetrasphaerol [14], and the methoxy derivative 4 of ioniol I [26], (ii) two bicyclic diterpenes, corotrienone (5) featuring the sphaerococcenol-like [5] α,β-unsaturated ketone analogue of bromocorodienol [12], and the double-bond positional isomer iso-bromocorodienol (6), and (iii) two brominated 6/6/6 tricyclic diterpenes, debromosphaerol (7), the unusual B/C cis-fused 17-debromo analogue of bromosphaerol [4], and the methoxy derivative 8 of 8-hydroxy-dihydro-sphaerococcenol [21]. The structures and relative stereochemistry of the isolated metabolites were established on the basis of 1D and 2D NMR, IR, UV, and HR-ESIMS data. ...

Reference:

Halogenated Diterpenes with In Vitro Antitumor Activity from the Red Alga Sphaerococcus coronopifolius

... The modification of natural products by semi-synthesis has been revealed to be a starting point for the generation of new analogue libraries with distinct properties from the original compounds, creating new lead structures for drug discovery [23]. Despite the red seaweed Sphaerococcus coronopifolius being revealed to be a prolific source of terpenes, most of them halogenated and with cytotoxic properties, there are only two studies that explore its chemical diversity as scaffolds for the synthesis of novel hemi-synthetic compounds [11,19,24]. As previously referenced, sphaerococcenol A was subjected to a base-catalyzed rearrangement, originating the new hemi-synthetic compound A, which by reduction, hydrogenation, and acetylation originated four new A analogues [19]. ...

Reference:

Sphaerococcenol A Derivatives: Design, Synthesis, and Cytotoxicity

... Marine sponges are a unique source for natural products, and even after decades of research, they still represent a rich reservoir of novel chemistry [1]. The phylum Porifera produces a huge variety of different natural product classes, and the genus Ircinia is well known for producing sesterterpenes (C 25 -terpenes) [2][3][4][5][6][7][8][9]. The chemical scaffolds of these terpenoids show a huge diversity with significant biological activity in almost all fields of biomedical research [10][11][12][13][14][15]. ...

Reference:

Discovery of Ircinianin Lactones B and C—Two New Cyclic Sesterterpenes from the Marine Sponge Ircinia wistarii

... A series of chromatographic separations of the CH 2 Cl 2 / MeOH extract of the red alga S. coronopifolius, collected in Agios Giannis bay off Parga in Greece, resulted in the isolation of 14 diterpenes (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) and one sesquiterpene (15) as the major constituents. By comparison of their spectroscopic and physical characteristics with those reported in the literature, the isolated metabolites were identified as bromosphaerol (1) [33,34], 12S-hydroxybromosphaerol (2) [35,36], 12R-hydroxy-bromosphaerol (3) [36,37], sphaerococcinol A (4) [38,39], 14R-hydroxy-13,14-dihydro-sphaerococcinol A (5) [36], 8-methoxy-dihydrosphaerococcenol (6) [40], 2S-hydroxy-isobromosphaerol (7) [41], bromosphaerol B (8) [36], bromosphaerodiol (9) [42], 1S-hydroperoxy-12S-hydroxy-bromosphaerodiol B (10) [36], 1S-hydroperoxy-12R-hydroxy-bromosphaerodiol B (11) [36], 1S-hydroxy-1,2-dihydrobromosphaerol (12) [41,43], bromotetrasphaerol (13) [37], 12R-hydroxy-bromocorodienol (14) [44] and allo-aromadendrene (15) [45] (Figure 1). ...

Reference:

Antifouling Activity of Halogenated Compounds Derived from the Red Alga Sphaerococcus coronopifolius: Potential for the Development of Environmentally Friendly Solutions