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Two new antimicrobial cytochalasin derivatives, 6β,7β-epoxydeoxaphomin C (1) and 12-hydroxydeoxaphomin C (2), a new natural occurring product 24-nor-cytochalasin B (3), together with two related known analogs (4-5) were isolated and identified from an endozoic fungus Curvularia verruculosa CS-129, isolated from the deep-sea squat lobster Shinkaia crosnieri which was collected in cold seep region of south China sea. The structures of new compounds were elucidated on the basis of detailed spectroscopic analysis and ECD calculation. The spectroscopic data of 24-nor-cytochalasin B (3) were reported for the first time. All compounds were tested for their antibacterial activities against human and aquatic pathogenic bacteria.

Two new antibacterial thiodiketopiperazine derivatives (TDKPs), 7-dehydroxyepicoccin H and 7-hydroxyeutypellazine F, along with seven known TDKP analogs, were isolated and identified from Epicoccum nigrum SD-388, a deep-sea-sediment-derived fungus. The structures of these compounds were elucidated on the basis of detailed spectroscopic analysis. The absolute configuration of 7-dehydroxyepicoccin H was established by X-ray crystallographic analysis, while 7-hydroxyeutypellazine F was determined by ECD experiment and TDDFT-ECD calculation. The antibacterial activities against human and aquatic pathogens were evaluated. 7-Dehydroxyepicoccin H and 7-hydroxyeutypellazine F displayed inhibitory activities against aquatic pathogens Vibrio vulnificus, V. alginolyticus, and Edwardsiella tarda, with MIC values ranging from 4.0 to 8.0 μg/mL.

Enantiomers of a 2-benzofuran-1(3H)-one derivative [(-)-1 and (+)-1] and four known analogs (2, 3, 4, 5) were isolated and identified from the culture extract of Eurotium rubrum MA-150, a fungus obtained from the mangrove-derived rizospheric soil. Their structures were established by detailed interpretation of nuclear magnetic resonance (NMR) data and the structure of (+/-)-1 was confirmed by single-crystal X-ray diffraction analysis. The absolute configuration of the enantiomers (-)-1 and (+)-1 was determined by means of online high-performance liquid chromatography - electronic circular dichroism (HPLC-ECD) measurements and time-dependent Density Functional Theory - electronic circular dichroism (TDDFT-ECD) calculations. Compounds (+/-)-1 as well as 2 and 3 exhibited potent DPPH radical scavenging activities with IC50 values of 1.23, 2.26, and 3.99 g/mL, respectively. Chirality 28:581-584, 2016. (c) 2016 Wiley Periodicals, Inc.

Two new oxepine-containing diketopiperazine-type alkaloids, varioloids A and B (1 and 2, resp.), were isolated from the algal-derived fungus Paecilomyces variotii EN-291. The structures and absolute configurations were determined by detailed interpretation of 1D- and 2D-NMR spectroscopic data and by analysis of acidic hydrolysates. Compounds 1 and 2 exhibited potent activity against the plant-pathogenic fungus Fusarium graminearum with MIC values of 8 and 4 mu g/ml, respectively.

Three new prenylated indole alkaloids, including two -carbolines, penipalines A and B (1 and 2, resp.), and one indole carbaldehyde derivative, penipaline C (3), as well as two known indole derived analogs, 4 and 5, were isolated from the deep-sea-sediment derived fungus Penicillium paneum SD-44 cultured in a 500-l bioreactor. The structures of the new compounds were determined on the basis of 1D- and 2D-NMR spectroscopy, as well as by high-resolution mass spectrometry. The new compounds 2 and 3 showed potent cytotoxic activities against A-549 and HCT-116 cell lines.

Cultivation of the fungal strain Eurotium cristatum EN-220, an endophyte obtained from the marine alga Sargassum thunbergii, resulted in the isolation of one new anthraquinone glycoside, 3-O-(alpha-D-ribofuranosyl)questinol (1) and one new orsellinic acid ester, cristatumside A (2), together with three known aromatic glycosides, 3-O-(alpha-D-ribofuranosyl)questin (3), isotorachrysone 6-O-alpha-D-ribofuranoside (4), and asperflavin ribofuranoside (5), as well as three anthraquinone derivatives, asperflavin (6), eurorubrin (7), and (+)-variecolorquinone A (8). The structures of these compounds were determined by extensive analysis of their spectroscopic data, as well as by their comparison with those in the literature. Each of the isolated compounds was evaluated for its antimicrobial activity and brine shrimp lethality.

Three new alkaloids, brocaeloids A-C (1-3), containing C-2 reversed prenylation, were isolated from cultures of Penicillium brocae MA-192, an endophytic fungus obtained from the fresh leaves of the marine mangrove plant Avicennia marina. Their structures were determined on the basis of 1D and 2D NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configuration of brocaeloid A (1) was established by gas-phase and solution conformational analysis and TDDFT-ECD calculations, which revealed that the fused hetero-ring adopted M-helicity conformation with axial orientation of the C-2 and C-3 substituents. The correct assignment of the hetero-ring conformation was found to be crucial in determining the relative and absolute configuration. Based on ECD calculations, the helicity of the 2,3-dihydroquinoline-4(1H)-one chromophore was correlated with the characteristic ECD transitions, and the resultant helicity rule was found to coincide with that of the chroman-4-one chromophore. X-ray single-crystal analysis of 1 by Cu-K-alpha radiation also confirmed the result of the stereochemical analysis obtained from ECD calculations. Brocaeloid B (2) showed lethality against brine shrimp (Artemia salina) with an LD50 value of 36.7 mu M.

Asperethers A–E (1–5), five new 20-nor-isopimarane diterpenoids having a 14,16-cyclic ether unit and possessing a unique 6/6/6/5 tetracyclic skeleton, which had not so far been described for this class of diterpenoids, were identified from the culture extract of Aspergillus wentii SD-310, a fungus obtained from a deep-sea sediment sample. The structures of these compounds were established on the basis of detailed interpretation of NMR and mass spectroscopic data, and their relative and absolute configurations were confirmed by NOESY data and X-ray crystallographic analysis, as well as by TDDFT calculations of their ECD spectra. Compounds 1–5 showed cytotoxic activities against several tumor cell lines.

Two new 6,8(14),22-hexadehydro-5,9-epidioxy-3,15-dihydroxy sterols, nigerasterols A and B (1 and 2, resp.), together with two known cyclopentapeptides, malformins A1 and C (3 and 4, resp.), were identified in the culture extract of Aspergillus niger MA-132, an endophytic fungus isolated from a fresh healthy sample of the mangrove plant Avicennia marina. The structures and relative configurations of these compounds were established on the basis of extensive spectroscopic analyses. The absolute configuration of compound 1 was determined by application of a modified version of Mosher's method. Nigerasterols A and B (1 and 2, resp.) represent the first 5,9-epidioxy-sterol compounds of marine origin, and they displayed potent activity against tumor cell lines HL60 and A549 in a preliminary bioassay.

Two new triazoles, chrysotriazoles A and B (1 and 2, resp.), along with two known quinazolinones, 3 and 4, two known 2-(4-hydroxyphenyl)acetamides, 5 and 6, and two known N-(4-hydroxystyryl)formamides, 7 and 8, were isolated and identified from the culture extract of Penicillium chrysogenum EN-118, an endophytic fungus obtained from the marine brown alga Sargassum pallidium. The structures of the isolated compounds were elucidated by NMR-spectroscopic analysis, and that of compound 1 was confirmed by X-ray crystallographic analysis of its p-bromobenzoate derivative. Compounds 4, 5, and 7 showed moderate cytotoxicities against Du145, A-549, and HeLa cell lines.

Two new tricyclic sesterterpenes, fusaprolifins A and B (1 and 2), and three new 2H-pyran-2-one derivatives, prolipyrones A C (35), were isolated and characterized from Fusarium proliferatum MA-84, an endophytic fungus obtained from the fresh tissue of the marine mangrove plant Bruguiera sexangula. In addition, two known sesterterpenes, terpestacin (6) and fusaproliferin (7), and one known 2H-pyran-2-one derivative, gibepyrone D (8), were also identified. The structures of these compounds were elucidated by detailed spectroscopic analyses. Fusaprolifin A (1) showed moderate activity against brine shrimp (Artemia salina), with a lethality rate of 49.5% at 100g/ml, while fusaprolifin B (2) showed weak activity.

Two new secoanthraquinone derivatives, wentiquinones A (1) and B (2), together with the eight known compounds 310, were isolated from the culture extracts of Aspergillus wentii EN-48, an endophytic fungus derived from an unidentified marine brown algal species of the genus Sargassum. The structures of these compounds were elucidated on the basis of extensive spectroscopic analysis.

Bioassay-guided isolation of a fungal strain Nigrospora sp. MA75, an endophytic fungus obtained from the marine semi-mangrove plant Pongamia pinnata, which was fermented on three different culture media, resulted in the isolation and identification of seven known compounds, 2, 3, and 5-9, from a medium containing 3.5% NaCl, while a new compound, 2,3-didehydro-19α-hydroxy-14-epicochlioquinone B (10) was obtained from the medium containing 3.5% NaI. In addition, two new griseofulvin derivatives, 6-O-desmethyldechlorogriseofulvin (1) and 6'-hydroxygriseofulvin (4), were isolated and identified from the rice solid medium. Dechlorogriseofulvin (2) and griseofulvin (3) were the major components in fermentation extracts of all these culture media, while compounds 1 and 4, 5 and 6, and 10 were only present in the extract of respective culture medium. The structures of these compounds were elucidated by detailed spectroscopic analysis, and the absolute configuration of 1 was determined by CD measurement. Compounds 9 and 10 exhibited antibacterial activities toward five tested bacterial strains, while compounds 5, 6, and 8 selectively inhibited MRSA, E. coli, and S. epidermidis, and compound 3 showed moderate activity against V. mali and S. solani. Moreover, compound 10 potently inhibited the growth of MCF-7, SW1990, and SMMC7721 tumor cell lines with IC(50) values of 4, 5, and 7 μg/ml, respectively.

Two new cembranoids, namely, sinumerolides A and B (1 and 2), one new steroid, 7 beta-hydroxygorgosterol (7), along with four known cembranoid derivatives (36), four known steroids (811), and four known africane sesquiterpenoids (1215), were isolated and identified from the marine soft coral Sinularia numerosa that was collected from South China Sea waters. The structures of these metabolites were elucidated on the basis of extensive spectroscopic analysis and by comparison of their spectral data with those of literature reports. The isolated compounds were evaluated for the antimicrobial and cytotoxic activity.

Cultivation of the fungal strain Eurotium rubrum, an endophytic fungus that was isolated from the inner tissue of the semi-mangrove plant Hibiscus tiliaceus, resulted in the isolation of one new dioxopiperazine alkaloid, 12-demethyl-12-oxo-eurotechinulin B (1), and one new anthraquinone derivative, 9-dehydroxyeurotinone (2), together with ten known compounds including variecolorin J (3), eurotechinulin B (4), variecolorin G (5), alkaloid E-7 (6), cryptoechinuline G (7), isoechinulin B (8), 7-isopentenylcryptoechinuline D (9), 2-O-methyl-9-dehydroxyeurotinone (10), emodin (11), and emodic acid (12). The structures of the isolated compounds were determined by extensive analysis of their spectroscopic data as well as by comparison with literature reports. Some of the purified compounds were evaluated for antibacterial, antifungal, and cytotoxic activities.

Two new halogenated sesquiterpenes, (8 beta) 10 bromo-3-chloro-2,7-epoxychamigr-9-en-8-ol (1) and 2 bromo-3 chlorobisabola-7(14),11 diene 6,10 diol (3). and one new phytol derived diterpene, epoxyphytyl acetate (4), along with cis- and trans 1-methylcyclohexane-1,4-diol (5 and 6) which were isolated from a natural source for the first time but have been previously synthesized were isolated from the marine red alga Laurencia composita and characterized In addition, a known sesquiterpene, pacifenediol (2), and the known furanone derivative 7 were also identified Their structures were established by MAR and mass spectroscopic methods.

Four new halogenated sesquiterpenes, 10-bromo-3-chloro-2,7-epoxychamigr-9-en-8a-of (1), 2,10 beta-dibromochamigra-2,7-dien-9 alpha-ol (2), (9S)-2-bromo-3-chloro-6,9-epoxybisabola-7(14),10-diene (3), and (9R)-2-bromo-3-chloro-6,9-epoxybisabola-7(14),10-diene (4), were characterized from the marine red alga Laurencia saitoi. In addition, two known halosesquiterpenes, 2,10-dibromo-3-chlorochamigr-7-en-9 alpha-ol (5) and isolaurenisol (6), were also isolated and identified. Their structures were established on the basis of extensive analysis of spectroscopic data.

A new fungus-derived benzodiazepine analogue, 2-hydroxycircumdatin C (1), and a compound which has been isolated from a natural resource for the first time, but has been previously synthesized, namely (11aS)-2,3-dihydro-7-methoxy-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5,11(10H,11aH)-dione (2), along with five structurally related known alkaloids (3-7), were isolated from Aspergillus ochraceus, an endophytic fungus derived from the marine brown alga Sargassum kjellmanianum. Their structures were established on the basis of spectroscopic methods. The absolute configuration of I was determined through CD evidence. Compound 1 displayed significant DPPH radical-scavenging activity with an IC(50) value of 9.9 mu M, which is 8.9-fold more potent than that of butylated hydroxytoluene (BHT), a well-known synthetic positive control.

Two new and one known squalenoid-derived triterpenoids. namely, laurenmariannol (1) and (21 alpha)-21-hydroxythyrsiferol (2). and the known thyrsiferol (3) were isolated and identified from the marine red alga Laurencia mariannensis, which was collected off the coast of Hainan and Weizhou Islands of China. The structures of these compounds were established by means of spectroscopic analyses, as well as by comparison with literature data. Compounds I and 2 displayed significant cytotoxic activity against P-388 tumor cells with IC(50) values of 0.6 and 6.6 mu g/ml, respectively.

Cultivation of the fungal strain Eurotium rubrum, an endophytic fungus that was isolated from the inner tissue of stems of the mangrove plant Hibiscus tiliaceus, resulted in the isolation of two new dioxopiperazine derivatives, namely, dehydrovariecolorin L (1) and dehydroechinulin (2), together with eight known dioxopiperazine compounds including variecolorin L (3), echinulin (4), isoechinulin A (5), dihydroxyisoechinulin A (6), preechinulin (7), neoechinulin A (8), neoechinulin E (9), and cryptoechinuline D (10). The structures of the isolated compounds were determined by extensive analysis of their spectroscopic data as well as by comparison with literature. Compounds 1, 2, 9, and 10 were investigated for their a,a-diphenyl-beta-picrylhydrazyl (DPPH) radical-scavenging activity. In addition, the new compounds, 1 and 2, were evaluated for their cytotoxic activity against the P-388, HL-60, and A549 cell lines.

Three new triterpenoids with the rarely occurring nigrum skeleton, namely (20E)-22-hydroxynigrum-20-en-3-one (1), 21 beta-hydroxynigrum-22(29)-en-3-one (2), and 21 alpha-hydroxynigrum-22(29)-en-3-one (3), were isolated from the mangrove plant Hibiscus tiliaceus. Additionally, five known triterpenoids including friedelin (4),12-oleanen-3 beta-ol (5), 3 beta-hydroxy-12-oleanen-28-oic acid (6),20(29)-lupen-3 beta,28-diol (7). and cucurbita-5,23-dien-3 beta,25-diol (8) were also isolated and identified. The latter structures were elucidated by a detailed NMR and MS analyses, as well as by comparison with reported literature data.

Jussiaea repens L. (JRL) is an edible medicinal plant and is also used as a vegetable by the local people in southwestern China. The crude extract and its four fractions derived from JRL were evaluated for the 1,1-diphenyl-2-picrylhydrazyl radical-scavenging ability, hydroxyl radical-scavenging capacity and the potassium ferricyanide reduction property. The ethyl acetate-soluble fraction (EAF) and EAF6 (a subfraction derived from EAF) were the most valuable fraction and subfraction, respectively. Furthermore, bioactivity-guided chromatographic fractionation revealed that three pure compounds greatly contributed to the antioxidant activities. Qualitative and quantitative analyses of the major antioxidant constituents in the extract were systematically conducted by NMR, mass spectral analyses and RP-HPLC. The result demonstrated that rosmarinic acid (2.00 mg g(-1) JRL dry weight) quercetin 3-O-beta-D-glucopyranoside (9.88 mg g(-1) JRL dry weight), and kaempferol 3-O-beta-D-glucopyranoside (1.85 mg g(-1) JRL dry weight) were the major antioxidative constituents in JRL. These compounds are reported for the first time from this plant.

Two new brominated diterpenes, namely, laurendecumtriol (1) and 11-O-deacetylpinnaterpene C (2), one new polybromoindole, 2,3,4,6-tetrabromo-1-methyl-1H-indole (7), and six known natural products were isolated and identified from the marine red alga Laurencia decumbens. Their structures were elucidated on the basis of detailed spectroscopic and mass-spectrometric analysis as well as by comparison with literature data. Based on 2D-NMR experiments, the previously reported NMR data for pinnaterpene C (3) were reassigned.

Asperamides A (1) and B (2), a sphingolipid and their corresponding glycosphingolipid possessing a hitherto unreported 9-methyl-C-20-sphingosine moiety, were characterized from the culture extract of Aspergillus niger EN-13, an endophytic fungus isolated from marine brown alga Colpomenia sinuosa. The structures were elucidated by spectroscopic and chemical methods as (2S,2'R,3R,3'E,4E,8E)-N-(2'-hydroxy-3'-hexadecenoyl)-9-methyl-4,8-icosadien-1,3-diol (1) and 1-O-beta-D-glucopyranosyl-(2S,2'R,3R,3'E,4E,8E)-N-(2'-hydroxy-3'-hexadecenoyl)-9-methyl-4,8-icosadien-1,3-diol (2). In the antifungal assay, asperamide A (1) displayed moderate activity against Candida albicans.

Three new polybrominated 1H-indoles, compounds 1-3, and three new aristolane sesquiterpenes, compounds 4-6, were isolated from the marine red alga Laurencia similis, together with seven known natural products. Their structures were elucidated on the basis of detailed spectroscopic and mass-spectrometric analyses, as well as by comparison with literature data.

Two new oxepine-containing diketopiperazine-type alkaloids, varioloids A and B (1 and 2, resp.), were isolated from the algal-derived fungus Paecilomyces variotii EN-291. The structures and absolute configurations were determined by detailed interpretation of 1D- and 2D-NMR spectroscopic data and by analysis of acidic hydrolysates. Compounds 1 and 2 exhibited potent activity against the plant-pathogenic fungus Fusarium graminearum with MIC values of 8 and 4 mu g/ml, respectively.

A new polyoxygenated dihydropyrano[2,3-c]pyrrole-4,5-dione derivative, pyranonigrin F (1), together with a related known compound, pyranonigrin A (2), were isolated and identified from Penicillium brocae MA-231, an endophytic fungus obtained from the fresh tissue of the marine mangrove plant Avicennia marina. The structures of these metabolites were determined based on comprehensive spectral interpretation and the absolute configuration of compound 1 was established by X-ray crystallographic analysis. Compounds 1 and 2 showed potent activity against a broad spectrum of human-, aqua-, and plant-pathogens. (C) 2015 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.

One new resorcylic acid derivative (IV), and five new loop-opened resorcylic acid-related congeners, including brocapyrone A (III), and brocaketones A-D (structure examples (I) and (II)) are isolated together with three known compounds.

Evaluation of the cytotoxic activity of the newly isolated indole alkaloids, dihydrocarneamide A (I) and iso-notoamide (II), reveals a weak cytotoxicity.

Two new β-carbolines, penipalines A and B (I), and the new indole carbaldehyde derivative, penipaline C (II) are isolated along with two known indole derived analogs from the deep-sea-sediment derived fungus Penicillium paneum SD-44 Compounds (Ib) and (II) exhibit potent cytotoxic activities against A-549 an HCT-116 cell lines.

The alkaloid varioexpine A (I) is isolated from the marine fungus Paecilomyces variotii and its structure is characterized by NMR spectroscopy and X-ray analysis.

The three new brocaeloids (I)-(III) are isolated from the cultures of penicillium brocae MA-192.

The anthraquinone glycoside (I), and the orsellinic ester, cristatumside A (II), are isolated along with three known aromatic glycosides as well as three known anthraquinone derivatives from the fungal strain Euroticum cristatum.

A new hydroperoxy-substituted cembranoid diterpene, 2-hydroperoxysarcophine (=(1aR*,4E,11E,14aR*)-2,3,6,7,10a,13,14,14a-octahydro-10a-hydroperoxy-1a,5,8,12-tetramethyloxireno[9,10]cyclote- tradeca[1,2-b]furan-9(1aH)-one; 1), was isolated from the marine soft coral Lobophytum crassum. Also isolated were two other cembranoid diterpenes, obtained for the first time from a natural source, i.e., 7 beta,8 beta-epoxy-4 alpha-hydroxycembra-1(15),2,11-trien-16,2-olide (2) and 7 beta,8 beta-epoxy-4 beta-hydroxycembra1(15),2,11-trien-16,2-olide (3), along with three further cembranoid derivatives, five sterols, and two open-chain metabolites. Their structures and relative configurations were elucidated on the basis of extensive spectroscopic analyses including 1D- and 2D-NMR, and HR-ESI-MS experiments.

Cristatumin A (I), B (II), C (III) and D (IV) are isolated together with 6 known compounds.

Two new polyoxygenated steroids, named penicisteroids A (I) and B (II), are obtained from the culture extract of Penicillium chrysogenum QEN-24S, an endophytic fungus isolated from an unidentified marine red algal species.

One new sesquiterpenoid, aristolan-1 alpha-bromo-9 beta,10 beta-epoxide (1), and one new indole alkaloid, 2,5-dibromo-N-methylindole (2), along with six sesquiterpenes and indoles were identified from the marine red alga Laurencia similis. Their structures were established on the basis of spectroscopic methods.

A new rearranged chamigrane sesquiterpene, named laurenokamurin, was isolated from the marine red alga Laurencia okamurai. Its structure was determined on the basis of spectroscopic methods. (C) 2008 Bin Gui Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

6-Bromo-1-(3-bromo-4,5-dihydroxybenzyl)phenanthro[4,5-bcd]furan-2,3,5-triol (urceolatin, 1), a highly oxygenated bromophenol containing an unprecedented naturally occurring benzylphenanthro[4,5-bcd]furan unit, was isolated from the marine red alga Polysiphonia urceolata. Its structure was established on the basis of extensive spectroscopic analysis. Compound 1 displayed significant DPPH radical-scavenging activity with an IC(50) value of 7.9 mu M, which is 10-fold more potent than that of the positive control, butylated hydroxytoluene.

Two new brominated diterpenes, namely, laurendecumtriol and 11-deacetylpinnaterpene C, were isolated and identified from the marine red alga Laurencia decumbens. Their structures were established on the basis of various NMR spectroscopic techniques and HR-ESI-MS analyses. (c) 2007 Bing Gui Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Chemical investigation of the basic fraction from the roots of Spiraea japonica var, acuta has resulted in the isolation of three new diterpene alkaloids, spiramines X (1), Y (2) and Z (3), along with five known compounds, spiradine F (4), and spiramines A, B, P (5), and U (6). The structures of 1-3 were determined by spectral and chemical methods. Antiplatelet aggregation activities of compounds (1-6) were tested.