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Four new steroids with an acetoxy linked at the end of the side chain, echrebsteroids A–D (1–4) were obtained from the South China Sea gorgonian Echinogorgia rebekka. The absolute configurations of 1–3 were determined using the modified Mosher’s method on the hydrolysis products. The isolation of the pair of epimers (2 and 3) represents the first reported separation of C-25 epimers of 26-acetoxy steroids. The (25R)-epimer (3) exhibited promising antiviral activity against respiratory syncytial virus with an IC50 value of 0.19 μM and a comparatively higher therapeutic ratio (TC50/IC50 = 128).

Twelve new 9,10-secosteroids designated as subergorgiaols A-L (1-12), along with four known analogues (13-16), were isolated from the gorgonian Subergorgia rubra collected from the South China Sea. Their planar structures and the relative configurations were elucidated by comprehensive spectroscopic methods including NOESY spectra. The absolute configuration of 1 was established by a dimolybdenum tetraacetate [Mo2(AcO)4] induced circular dichroism (ICD) procedure and the modified Mosher's method. Compounds 1-12 represent the first series of 9,10-secosteroids characterized with a hydroxy group at C-8, which are 8-OH derivatives of astrogorgiadiols/calicoferols. Compound 4 exhibited cytotoxicity against the cervical carcinoma cell line (CaSki) with an IC50 value of 2.4 μM, and 6 showed toxicity toward brine shrimp Artemia salina with an LC50 value of 2.0 μM.

Three new 14-membered resorcylic acid lactones, cochliomycins D-F, 1-3, and eight known analogues, 4-11, were isolated from the sea anemone-derived fungus Cochliobolus lunatus. Compounds 1-4 are diastereomers differing from each other by the absolute configurations of the 4',5'-diol chiral centers. The absolute configurations of 1-4 were established by the CD exciton chirality method and TDDFT ECD calculations. In antifouling assays, 1, 3-6, and 6a exhibited potent antifouling activities against the larval settlement of the barnacle Balanus amphitrite at nontoxic concentrations, with EC50 values ranging from 1.82 to 22.5 μg/mL. Noticeably, fungicide whole-plant assays indicated that 6 showed excellent activity on the Plasmopara viticola preventative test at 6 ppm and concentration-dependent activity on the Phytophthora infestans preventative application at 200, 60, and 20 ppm. Preliminary structure-activity relationships are also discussed.

Five new 9,11-secosteroids 1, 2, and 4-6, and seven known analogs, 3 and 7-12, with the same steroid skeleton, (5αH)-3β,6α,11-trihydroxy-9,11-secocholest-7-en-9-one, were isolated from the South China Sea gorgonian Subergorgia suberosa. Among them, 2/3 and 4/5 are C(24)-epimeric mixtures, and 6/7 is an (E)/(Z) mixture of (C(24)C(28)). Their structures and relative configurations were elucidated by using comprehensive spectroscopic methods including NOESY spectra. The absolute configuration of the steroidal nucleus was established by the modified Mosher method applied to 10 and on the basis of a common biogenesis for all of these compounds. All isolated compounds, 1-12, and five synthetic acetylated derivatives, 12a-12e, were evaluated for their cytotoxicities in vitro. Compounds 4/5, 11, 12, and 12b-12d showed cytotoxic activities against K562 cell line with the IC50 values ranging from 1.09 to 8.12 μM.

One new δ-valerolactone (1) and one new natural phenolic glycoside 2, together with four known compounds 3–6, were isolated from the fruits of Ligustrum lucidum. Their structures were elucidated on the basis of spectral data. The chemical transformation from 2 to 3 was observed. The immunomodulatory activities of the compounds were also evaluated.

[Sun, Ling-Ling; Shao, Chang-Lun; Wang, Chang-Yun] Ocean Univ China, Sch Med & Pharm, Key Lab Marine Drugs, Minist Educ, Qingdao 266003, Peoples R China; [Mei, Wen-Li; Dai, Hao-Fu] Chinese Acad Trop Agr Sci, Inst Trop Biosci & Biotechnol, Key Lab Trop Crop Biotechnol, Minist Agr, Haikou 571101, Peoples R China; [Huang, Hui] Chinese Acad Sci, S China Sea Inst Oceanol, Guangzhou 510000, Guangdong, Peoples R China

A new dihydroisocoumarin derivative containing an isoprenyl group, 5-(3'-methylbut-2'-enyloxy)-3,4-dihydro8-hydroxy-3-methylisochromen-1-one (1), was isolated from the mangrove fungus Cephalosporium sp. from the South China Sea. The structure of compound 1 was established by comprehensive analysis of the spectral data, especially 2D NMR spectra.

Sargassum pallidum (Turn.) C. Ag., a kind of brown algae distributed mainly in the Shandong and Liaoning Provinces of China, has been used in folk medicine for a long time in China [1]. Only several polysaccharides from S. pallidum with antitumor and antioxidant activities have been reported [2]. However, there are no reports on phytochemical analysis of the secondary metabolites. In this paper, two new natural keto-acid derivatives, 2,6,6-trimethyl-4-oxo-2-cyclohexene-1-acetic acid (1) and 2,6,6-trimethyl-4-oxo-2-cyclohexene-1-acetic acid methyl ester (2), were reported from the whole plant of S. pallidum (Turn.) C. Ag.. Their structures were established by comprehensive analysis of the spectral data, especially 2D NMR spectral results. Compound 3 was isolated for the first time from the marine enviroment. Compound 1 was obtained as a yellow oil, [ ] D –7.96 (c 9.15, MeOH). The molecular formula of 1 was established as C11H16O3 from the results of ESI-MS ([M + H] + at m/z 197) and its NMR data. The molecular formula indicated four degrees of unsaturation within the molecule. The IR spectrum showed the presence of carbonyl groups (1653, 1651 cm–1). The 13C NMR and DEPT spectra showed that 1 has 11 carbon signals, attributable to 3 methyl, 2 methylene, 2 methine, and 4 quaternary carbons, including 1 ketone carbonyl at C 202.1 and 1 carboxyl at C 180.0. The 1H NMR spectrum together with HMQC data displayed one olefinic proton signal at H 5.79 (s), one triple signal due to one methine proton at H 2.70, two methylene group signals at H 2.02, 2.40 and H 2.17, 2.49, and three methyl group signals at H 1.03 (s, CH3), 1.04 (s, CH3), 2.03 (s, CH3). The whole structure of 1 was mainly determined by the HMBC spectra (Table 1). The correlations from H-9 proton to C-1, C-2, C-6, C-11 and the correlations from H-1 to C-2, C-3, C-6, C-9, C-11 suggested that C-1 was directly connected with C-2, C-6, and C-9. The correlations from H-5 to C-1, C-3, C-4, C-6, C-7, C-8, and the correlations from H-7, H-8 to C-1, C-5, C-6 indicated that C-5 was linked with C-4 and C-6. The correlations from H-3 to C-1, C-2, C-10 and the correlations from H-5 to C-3 confirmed that there were linkages between the C-3 and C-2, C-4 positions. Thus protons of 10-CH3 showed the HMBC correlations to the C-1, C-2 and C-3, placing the methyl group at the C-2 position. Thus, the structure of compound 1 was identified as 2,6,6-trimethyl-4-oxo-2-cyclohexene-1-acetic acid. As is known, compound 1 has not been reported previously as a natural product and was only obtained as a synthetic compound [3, 4].

Two new benzaldehyde derivatives, 6-ethyl-2-hydroxy-4-methoxy-3-methylbenzaldehyde (1), 6-ethyl-2,4-dihydroxy-3-methylbenzaldehyde (2), together with 2, 4-dihydroxy-3,6-dimethylbenzaldehyde (3) were isolated from mangrove fungus (No. ZZF 32#) from the South China Sea. The structures of compounds 1 and 2 were established by comprehensive analysis of the spectral data, especially 2D NMR spectral results.

Two new acids 1 and 2, together with a known compound, purpactin A (3), were isolated from endophytic fungus No. ZZF13. Their structures were elucidated on the basis of 1D, 2D NMR, and HREIMS spectra.

Asperterpenol A (1) and asperterpenol B (2), two novel sesterterpenoids with an unusual 5/8/6/6 tetracyclic ring skeleton, were isolated from a mangrove endophytic fungus Aspergillus sp. 085242. The structures were elucidated on the basis of spectroscopic methods and the absolute configurations determined by single-crystal X-ray diffraction analysis. Compounds 1 and 2 inhibit acetylcholinesterase with IC50 values of 2.3 and 3.0 μM, respectively.

Fumiquinazoline L (1), an alkaloid with a heptacyclic skeleton formed via a bridging hemiaminal linkage, was isolated from a gorgonian-derived Scopulariopsis sp. fungus. The structure and absolute configuration of the new compound were identified by comprehensive spectroscopic data and X-ray diffraction analysis. During acid hydrolysis of 1, the isomerization of the valine residue was observed and also studied in different conditions. Fumiquinazoline L (1) showed no cytotoxic or antibacterial activities.

Two new prenylated indole alkaloids, 17-epi-notoamides Q and M (1 and 2), and two new phenyl ether derivatives, cordyols D and E (9 and 13), together with 10 known compounds (3–8, 10–12, 14) were isolated from a marine-derived Aspergillus sp. fungus. Among them, 1/5 and 2/4 were pairs of epimers. The planar structures and absolute configurations of the new compounds were determined by extensive NMR spectroscopic data as well as CD spectra. The absolute configuration of 3 was confirmed by single-crystal X-ray diffraction analysis for the first time. All isolated metabolites (1–14) and eight synthetic phenyl ether derivatives (12a, 14a–14g) were evaluated for their antibacterial activities in vitro. The polybromide phenyl ether 14g showed pronounced antibacterial activity against Staphylococcus epidermidis with an MIC value of 0.556 μM, stronger than that of the positive control ciprofloxacin (MIC = 3.13 μM).

Ten new fungal metabolites, including three hydroisocoumarins, penicimarins A–C (1–3), three isocoumarins, penicimarins D–F (6–8), and four benzofurans, penicifurans A–D (11–14), together with four known isocoumarin derivatives (4, 5, 9, 10), were obtained from the sponge-derived fungus Penicillium sp. MWZ14-4, collected from the South China Sea. Their planar structures and relative configurations were elucidated by detailed analysis of spectroscopic data and by comparison with related known compounds. The absolute configurations of 1–4 were assigned by the modified Mosher’s method and TDDFT ECD calculations together with comparison of their CD spectra. Compound 1 represents a rare naturally occurring isocoumarin derivative with 4-substitution, but no substituent at the 3-position. These compounds were evaluated for antibacterial activities and cytotoxic activities in vitro. Among them, penicifuran A (11) exhibited inhibitory activity against Staphylococcus albus with an MIC value of 3.13 μM.

One new hydroanthraquinone dimer with a rare C-9–C-7′ linkage, nigrodiquinone A (1), and four known anthraquinone monomers 2–5, were isolated from a fungus Nigrospora sp. obtained from the zoanthid Palythoa haddoni collected in the South China Sea. The structure of 1 was established through extensive NMR spectroscopy, and the absolute configuration was elucidated by comparing computed electronic circular dichroism (ECD) and optical rotations (OR) with experimental results. All the compounds were evaluated for antiviral activity, and 1 was also evaluated for antibacterial activity. Compound 4 displayed mild antiviral activity against coxsackie virus (Cox-B3) with the IC50 value of 93.7 μM, and 5 showed an IC50 value of 74.0 μM against respiratory syncytial virus (RSV).

Chemical investigation of the ethanol extract of soft coral Sinularia sp. collected from the South China Sea led to the isolation of three new polyoxygenated sterols, (3S,23R,24S)-ergost-5-ene-3β,23α,25-triol (1), (24S)-ergostane-6-acetate-3β,5α,6β,25-tetraol (2), (24S)-ergostane-6-acetate-3β,6β,12β,25-tetraol (3) together with three known ones (4-6). The structures, including relative configurations of the new compounds (1-3), were elucidated by detailed analysis of spectroscopic data (IR, UV, NMR, MS) and by comparison with related reported compounds. The absolute configuration of 1 was further determined by modified Mosher's method. Compound 5 exhibited moderate cytotoxicity against K562 cell line with an IC(50) value of 3.18 μM, but also displayed strong lethality toward the brine shrimp Artemia salina with a LC(50) value of 0.96 μM.

Chemical investigation of a marine-derived fungus Nigrospora sp., isolated from an unidentified sea anemone, yielded two new hydroanthraquinone analogues, 4a-epi-9α-methoxydihydrodeoxybostrycin (1) and 10-deoxybostrycin (2), together with seven known anthraquinone derivatives (3-9). The structures of the two new compounds were established through extensive NMR spectroscopy as well as a single-crystal X-ray diffraction analysis using Cu Kα radiation. The antibacterial activities of compounds 1-9 and 10 acetyl derivatives (6a, 7a, 8a-8g, 9a) were evaluated in vitro. Compound 6a, the acetylated derivative of 6, exhibited promising activity against Bacillus cereus with an MIC value of 48.8 nM, which was stronger than that of the positive control ciprofloxacin (MIC = 1250 nM). Analysis of the antibacterial screening data for the metabolites and their acetyl derivatives revealed the key structural features required for this activity.

Cadmium (Cd) is a toxic, nonessential transition metal and contributes a health risk to humans, including various cancers and cardiovascular diseases; however, underlying molecular mechanisms remain largely unknown. Cells transmit information to the next generation via two distinct ways: genetic and epigenetic. Chemical modifications to DNA or histone that alters the structure of chromatin without change of DNA nucleotide sequence are known as epigenetics. These heritable epigenetic changes include DNA methylation, post-translational modifications of histone tails (acetylation, methylation, phosphorylation, etc), and higher order packaging of DNA around nucleosomes. Apart from DNA methyltransferases, histone modification enzymes such as histone acetyltransferase, histone deacetylase, and methyltransferase, and microRNAs (miRNAs) all involve in these epigenetic changes. Recent studies indicate that Cd is able to induce various epigenetic changes in plant and mammalian cells in vitro and in vivo. Since aberrant epigenetics plays a critical role in the development of various cancers and chronic diseases, Cd may cause the above-mentioned pathogenic risks via epigenetic mechanisms. Here we review the in vitro and in vivo evidence of epigenetic effects of Cd. The available findings indicate that epigenetics occurred in association with Cd induction of malignant transformation of cells and pathological proliferation of tissues, suggesting that epigenetic effects may play a role in Cd toxic, particularly carcinogenic effects. The future of environmental epigenomic research on Cd should include the role of epigenetics in determining long-term and late-onset health effects following Cd exposure.

Five new hydroanthraquinone derivatives, tetrahydroaltersolanols C-F (1-4) and dihydroaltersolanol A (5), and five new alterporriol-type anthranoid dimers, alterporriols N-R (12-16), along with seven known analogues (6-11 and 17), were isolated from the culture broth and the mycelia of Alternaria sp. ZJ-2008003, a fungus obtained from a Sarcophyton sp. soft coral collected from the South China Sea. Their structures and the relative configurations were elucidated using comprehensive spectroscopic methods including 1D and 2D NOE spectra as well as single-crystal X-ray crystallography. Compound 13 represents the first isolated alterporriol dimer with a C-4-C-4' linkage, and the absolute configuration of 4 was determined using the modified Mosher's method. Compounds 1 and 15 exhibited antiviral activity against the porcine reproductive and respiratory syndrome virus (PRRSV), with IC₅₀ values of 65 and 39 μM, respectively. Compound 14 showed cytotoxic activity against PC-3 and HCT-116 cell lines, with IC₅₀ values of 6.4 and 8.6 μM, respectively.

Four new bisabolane-type sesquiterpenoids, aspergiterpenoid A (1), (−)-sydonol (2), (−)-sydonic acid (3), and (−)-5-(hydroxymethyl)-2-(2′,6′,6′-trimethyltetrahydro-2H- pyran-2-yl)phenol (4) together with one known fungal metabolite (5) were isolated from the fermentation broth of a marine-derived fungus Aspergillus sp., which was isolated from the sponge Xestospongia testudinaria collected from the South China Sea. Four of them (1–4) are optically active compounds. Their structures and absolute configurations were elucidated by using NMR spectroscopic techniques and mass spectrometric analysis, and by comparing their optical rotations with those related known analogues. Compounds 1–5 showed selective antibacterial activity against eight bacterial strains with the MIC (minimum inhibiting concentrations) values between 1.25 and 20.0 µM. The cytotoxic, antifouling, and acetylcholinesterase inhibitory activities of these compounds were also examined.

Two new steroidal glycosides, fragilioside A (1) and fragilioside B (2), along with five known compounds (3-7) were isolated from the gorgonian Dichotella fragilis (Ridleg) collected from the South China Sea. The structures of the new compounds (1 and 2) were elucidated by comprehensive analysis of spectral data, especially 2D NMR. The brine shrimp lethality and antifouling activity of the isolated compounds were also evaluated.

Three new phenolic bisabolane sesquiterpenoid dimers, disydonols A-C (1-3), and one known compound (S)-(+)-sydonol (4) were isolated from the fermentation broth of a marine-derived fungus Aspergillus sp., which was isolated from the sponge Xestospongia testudinaria collected from the South China Sea. Their structures were elucidated on the basis of comprehensive spectral analysis including 1D and 2D NMR spectra and HR-ESI-MS. These compounds were evaluated for cytotoxic activity against HepG-2 and Caski human tumour cell lines. Among them, compounds 1 and 3 exhibited cytotoxicity against the two cell lines.

Four new norsesquiterpene peroxides, named talaperoxides A-D (1-4), as well as one known analogue, steperoxide B (5, or merulin A), have been isolated from a mangrove endophytic fungus, Talaromyces flavus. Their structures were elucidated mainly by 1D and 2D NMR. Structures of 1, 2, and 5 were further confirmed by single-crystal X-ray diffraction, and their absolute configurations were also determined using copper radiation. Cytotoxic activities of compounds 1-5 were evaluated in vitro against human cancer cell lines MCF-7, MDA-MB-435, HepG2, HeLa, and PC-3. Compounds 2 and 4 showed cytotoxicity against the five human cancer cell lines with IC50 values between 0.70 and 2.78 μg/mL.

Aspergilone A(I) possessing an azaphilone structure, and its symmetrical dimer with a unique methylene bridge, aspergilone B(II), are isolated from the culture broth of the marine derived title plant.

A new diimide derivative, named (-)-byssochlamic acid bisdiimide (1), was isolated from the mixed broth of two mangrove fungi (strain no. K38 and E33) from the South China sea coast. The structure of 1 was determined by comprehensive spectroscopic methods, including 1D and 2D NMR (COSY, HMQC, and HMBC) and semi-synthesis. Primary bioassays showed that 1 had weak cytotoxic activity against Hep-2 and HepG2 cells.

Two new eicosanoids with a unique isovalerianic acid ester group at C-12, named dichotellates A (1) and B (2), were isolated from the gorgonian Dichotella gemmacea collected from the South China Sea using bioassay-guided fractionation. Their structures were established on the basis of extensive spectroscopic analysis including one-dimensional (1D) and two-dimensional (2D) NMR as well as high-resolution ESI-MS experiments. These two compounds were evaluated for their lethal activity toward brine shrimp Artemia salina and both showed weak activity.

Three new phenolic bisabolane-type sesquiterpenoids: (+)-methyl sydowate (1), 7-deoxy-7,14-didehydrosydonic acid (2), and 7-deoxy-7,8-didehydrosydonic acid (3), together with two known fungal metabolites were isolated from the fermentation broth of a marine-derived fungus Aspergillus sp., which was isolated in turn from a gorgonian Dichotella gemmacea collected from the South China Sea. Their structures were elucidated by combined spectroscopic methods, and the structure of 1 was further confirmed by single-crystal X-ray data.

A new pyrrolyl 4-quinolinone alkaloid with an unprecedented ring system, named penicinoline (1) was isolated from a mangrove endophytic fungus. The structure of 1 was elucidated by spectroscopic methods and comparison with its derivative, penicinotam (1a), an unexpected lactam that was obtained from 1 by intramolecular dehydration. The structure of 1a was unambiguously confirmed by single-crystal X-ray analysis. Penicinoline (1) showed potent in vitro cytotoxicity toward 95-D and HepG2 cell lines with IC(50) values of 0.57 and 6.5 microg/mL, respectively.

Chemical examination of the soft coral Sarcophyton infundibuliforme collected front the South China Sea resulted in the isolation of the three new O-glycosylglycerol derivatives sarcoglycosides A-C (1-3), together with two known compounds, chimyl alcohol (4) and hexadecanol (5). Their structures were elucidated by combined spectral and chemical methods. All the compounds showed moderate toxicity to brine shrimps Artemia salina.

A new sesquiterpenoid compound, microsphaeropsisin A (1), together with three known dihydroisocoumarin compounds, (R)-mellein (2), 4-hydroxymellein (3) and 5-hydroxymellein (4) were isolated from the culture of the mangrove fungus (No. DZ39). The structure of the new compound was established by comprehensive spectral analysis, especially 2D NMR spectroscopy.

The metabolites of a marine mangrove fungus (Penicillium sp. No. 2556) were studied in this paper and six compounds were isolated from the fermentation liquid. Their structures were elucidated by spectroscopy methods as Sch54796 (1), Sch54794 (2), 4-hydroxybenzoic acid (3), urail (4), succinic acid (5), Vermopyrone (6). Among them, compounds 1, 2 and 6 were firstly isolated from Penicillium sp., Coumpounds 1 and 2 remarkably inhibited the growth of cancer cell lines hep2 and hepG2.

Three metabolites named phomopsin A (1), B (2) and C (3), together with two known compounds cytosporone B (4) and C (5), were isolated from the mangrove endophytic fungus, Phomopsis sp. ZSU-H76 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly by 1D and 2D NMR spectroscopic techniques. The medium-sized cyclic phenol ether based on 1 or 2 is rare in natural products. In bioassays, compounds 1, 2, and 3 had no significant antibiotic activities, but compounds 4 and 5 inhibited two fungi Candida albicans and Fusarium oxysporum with an MIC ranging from 32 to 64 microg/ml.

Two new xanthones, 8-(methoxycarbonyl)-1-hydroxy-9-oxo-9H-xanthene-3-carboxylic acid (1) and dimethyl 8-methoxy-9-oxo-9H-xanthene-1, 6-dicarboxylate (2) and one known xanthone methyl 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate (3) were isolated from the culture broth of the mangrove fungus Penicillium sp. (ZZF 32#) collected from the South China Sea. Their structures were established by comprehensive analysis of one-dimensional (1D) and two-dimensional (2D) NMR data. The structure of compound 3 was confirmed by X-ray crystallography, which led to the suggestion that janthinone (4) might have the same structure as 3. Compounds 1–3 were inactive against KB or KBv200 cells during cytotoxicity evaluations. Copyright © 2008 John Wiley & Sons, Ltd.

The title compound, C9H9Cl2NO2, is a natural product isolated from the endophytic fungus No. B77 of the mangrove tree from the South China Sea coast. In the crystal structure, the molecules lie on twofold axes and form offset stacks through face-to-face π–π interactions. Adjacent molecules in each stack are related by a centre of inversion and have an interplanar separation of 3.53 (1) Å, with a centroid–centroid distance of 3.76 (1) Å. Between stacks, there are C—H...O interactions to the nitro groups and Cl...Cl contacts of 3.462 (1) Å.

In the title compound, [Cd(C(6)H(6)N(2)O)(2)(H(2)O)(4)](C(10)H(8)O(6)S(2)), the Cd(II) ion is located on a crystallographic inversion centre. An octa-hedral coordination geometry is defined by four water mol-ecules in one plane, and two trans N-atom donors of the nicotinamide ligands. The biphenyl-4,4'-disulfonate anion also lies on a crystallographic inversion centre. In the crystal structure, the complex cations are connected to the counter-anions via N-H⋯O and O-H⋯O hydrogen bonds, forming a three-dimensional network.

Diverse arrays of new bioactive secondary metabolites have been isolated from marine microorganisms; and the number of publications in this area has greatly increased in recent years. In this review, the emphasis is placed on new compounds with antitumor, enzyme inhibitors, antivirus, and other bioactive metabolites from fungi, bacteria, actinomycetes, and cyanobacteria reported between 2000 and 2005. Supply is a major limitation in the development of marine bioproducts, and the methods for supplying these products are important. So in this review, the secondary major point is placed on the chemical synthetic studies. References of 390 structures and 263 citations are overall presented in this review.

A novel nitro-phenyl glucoside (1) was isolated from mangrove endophytic fungus (fungus B60), collected from the Shenzhen mangrove Acanthus ilicifolius linn. Four related nitro-phenyl compounds (2-5) were also obtained, which were isolated for the first time as natural products. Their structures were established on the basis of NMR spectroscopic, mass spectrometric data and some chemical transformations. In the preliminary bioassay, compound 1 had a slight inhibitory effect on alpha-glucosidase with an IC(50) of 160.3 microM.

Two new natural products, named paecilin A (1) and B (2), together with two known compounds secalonic acid D (3) and (11)-cytochalasa-6(12),13-diene-1,21-dione-16,18-dimethyl-7-hydroxy-10-phenyl-(7S*,13E,16S*,18S*) (4), were isolated from the mangrove endophytic fungus, Paecilomyces sp. (tree 1-7) from the South China Sea. 1D and 2D NMR experiments including COSY, HMQC, and HMBC were used for the determination of their structures. In our cytotoxicity assays, secalonic D (3) showed cytotoxicity toward KB cells with IC(50) < 1 microg ml(-1) and inhibiting human topoisomerase I with IC(50) at 0.16 micromol ml(-1). 1, 2, and 4 showed no activity to KB cells.

We report the unambiguous assignments of the (1)H and (13)C NMR spectra of one new natural product, namely, 6,8-di-O-methyl versiconol (1) together with one known anthraquinone aversin (2) and two xanthones 5-methoxysterigmatocystin (3) and sterigmatocystin (4). These compounds were all isolated from the mangrove endophytic fungus ZSUH-36 from the South China Sea. 1D and 2D NMR experiments including COSY, HMQC and HMBC were used to elucidate the structures. Variations in the (1)H NMR spectrum of 6,8-di-O-methyl versiconol (1) were also observed in the temperature range 25-75 degrees C. In addition, the plausible biogenetic path from 1 to 2 is discussed.

The complete 1H and 13C NMR assignments are reported for the novel natural product Bacillosporin D together with the known compound Bacillosporin C. These compounds containing seven rings were isolated from the mangrove endophytic fungus SBE-14 from the South China Sea. 1D and 2D NMR experiments, including COSY, HMQC and HMBC were used to the determination of the structures and NMR assignments. It is proposed that 1 was biogenetically produced by transforming 2. Transforming a lactone to an anhydride is unusual in nature. Copyright © 2007 John Wiley & Sons, Ltd.

Three metabolites named phomopsin A (1), B (2) and C (3), together with two known compounds cytosporone B (4) and C (5), were isolated from the mangrove endophytic fungus, Phomopsis sp. ZSU-H76 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly by 1D and 2D NMR spectroscopic techniques. The medium-sized cyclic phenol ether based on 1 or 2 is rare in natural products. In bioassays, compounds 1, 2, and 3 had no significant antibiotic activities, but compounds 4 and 5 inhibited two fungi Candida albicans and Fusarium oxysporum with an MIC ranging from 32 to 64 microg/ml.

− Chemical investigation of the fermentation broth of a Soft Coral-Derived fungus Pestalotiopsis sp., led to the isolation of a new phthalide derivative, pestalotiolide A (1), three known analogues (2, 3 and 4), along with 5'-O-acetyl uridine (5) first isolated as a natural product. The structure of the new compound (1) was established by comprehensive spectroscopic analysis and chemical methods. Compounds 1 4 possessed varying degrees of antiviral activities, which was reported for the first time. Compared to the positive control ribavirin (IC50 = 418.0 μM), pestalotiolide A (1) exhibited significant anti-EV71 activity in vitro, with an IC50 value of 27.7 μM. Furthermore, the preliminary structure-activity relationship of antiviral activities was also discussed.

The title compound, C13H16O4, was isolated from culture extracts of the endophytic fungus Cephalosporium sp. The ester and ether substituents are twisted only slightly out of the benzene ring plane, making dihedral angles of 2.16 (2) and 3.63 (5)°, respectively. The non-H atoms of all three substituents are almost coplanar with the benzene ring, with an r.m.s. deviation of 0.0284 Å from the mean plane through all non-H atoms in the structure. A weak intramolecular O—H...O hydrogen bond contributes to this conformation. In the crystal structure, molecules are linked into a one-dimensional chain by intermolecular O—H...O hydrogen bonds. Weak non-classical C—H...π contacts are also observed in the structure.