Feng-Ping Miao

Absolute Configurations of Unique Harziane Diterpenes from Trichoderma Species

Harzianone (2), a new harziane diterpene, was isolated from an alga-endophytic isolate of Trichoderma longibrachiatum. The structure and absolute configuration of 2 were unambiguously identified by NMR and mass spectrometric methods as well as quantum chemical calculations. The absolute configuration of harziandione (1) was supported by calculation of optical rotation, and the structure of isoharziandione was revised to 1 on the basis of (13)C NMR data comparison and calculation.

Aspeverin, a New Alkaloid from an Algicolous Strain of Aspergillus versicolor

A novel carbamate- and cyano-containing alkaloid, aspeverin (1), was isolated from the culture of an algicolous Aspergillus versicolor strain (dl-29). The structure and absolute configuration were unambiguously identified by NMR, IR, ECD, and mass spectrometric methods as well as quantum chemical calculations. 1 exhibited potent bioactivities against some marine-derived organisms.

Terretonin, ophiobolin, and drimane terpenes with absolute configurations from an algicolous Aspergillus ustus

One new meroterpene, 1,2-dihydroterretonin F (2), five new sesterterpenes, (6α)-21-deoxyophiobolin G (3), (6α)-16,17-dihydro-21-deoxyophiobolin G (4), ophiobolin U (5), ophiobolin V (6), and ophiobolin W (7), two new sesquiterpenes, (6-strobilactone-B) esters of (E,E)-6,7-epoxy-2,4-octadienoic acids (13 and 14), and twelve known terpenes (1, 8–12, and 15–20) were isolated from Aspergillus ustus, a fungus from the fresh tissue of marine green alga Codium fragile. Their structures and absolute configurations were identified by NMR and mass spectroscopic methods as well as quantum chemical calculations. Some of the isolates exhibited antibacterial activity and brine shrimp toxicity.

Aspewentins A-C, Norditerpenes from a Cryptic Pathway in an Algicolous Strain of Aspergillus wentii

Through addition of suberoylanilide hydroxamic acid, two new aromatic norditerpenes, aspewentins A (1) and B (2), along with an oxygenated derivative, aspewentin C (3), were obtained from the culture of an Aspergillus wentii strain (na-3) isolated from the tissue of the brown alga Sargassum fusiforme. The structures and absolute configurations were unambiguously elucidated by spectroscopic analyses and quantum chemical calculations. Aspewentins A-C were produced before sporulation and exhibited potent bioactivities against some marine-derived organisms.

Three new xanthone derivatives from an algicolous isolate of Aspergillus wentii

Three new xanthone derivatives, yicathin A (1), yicathin B (2), and yicathin C (3), and three known anthraquinone derivatives, alatinone (4), 1,5‐dihydroxy‐3‐methoxy‐7‐methylanthraquinone (5), and 5‐hydroxy‐1,3‐dimethoxy‐7‐methylanthraquinone (6), were isolated from the cultures of Aspergillus wentii pt‐1, an endophytic fungus isolated from the marine red alga Gymnogongrus flabelliformis. Their structures were unambiguously elucidated by NMR and mass spectroscopic methods as well as quantum chemical calculations. Compound 2 was active against Escherichia coli, and 3 could inhibit E. coli, Staphylococcus aureus, and Colletotrichum lagenarium. Copyright

Steroids and an oxylipin from an algicolous isolate of Aspergillus flavus

A new oxylipin, (8E,12Z)‐10,11‐dihydroxyoctadeca‐8,12‐dienoic acid (1), a new steroid, 3β,4α‐dihydroxy‐26‐methoxyergosta‐7,24(28)‐dien‐6‐one (2), and four known steroids, episterol (3), (22E,24R)‐ergosta‐7,22‐dien‐3β,5α,6α‐triol (4), (22E,24R)‐ergosta‐5,22‐dien‐3β‐ol (5), and (22E,24R)‐ergosta‐4,6,8(14),22‐tetraen‐3‐one (6), were isolated from the cultures of Aspergillus flavus, an endophytic fungus isolated from the marine red alga Corallina officinalis. Their structures and relative stereochemistry were elucidated by 1D, 2D NMR and mass spectroscopic techniques. 1 and 2 exhibited low activity to inhibit acetylcholinesterase and no activity against plant pathogenic fungi Colletotrichum lagenarium and Fusarium oxysporum. Copyright

Trichocitrin, a new fusicoccane diterpene from the marine brown alga-endophytic fungus Trichoderma citrinoviride cf-27

Abstract One new diterpene, trichocitrin (1), and four known secondary metabolites, nafuredin (2), 5-hydroxy-2,3-dimethyl-7-methoxychromone (3), 24-methylenecycloartanol (4) and citrostadienol (5), were isolated from the culture of marine brown alga-endophytic Trichoderma citrinoviride cf-27. Trichocitrin (1) represents the first Trichoderma-derived and furan-bearing fusicoccane diterpene, and its structure and relative configuration were identified by analysis of 1D/2D NMR and mass spectroscopic data. Compounds 1 and 2 exhibited 8.0- and 9.5-mm inhibition zones, respectively, against Escherichia coli at 20 μg/disc and 54.1 and 36.7% growth inhibition, respectively, of Prorocentrum donghaiense at 80 μg/mL.

Sesquiterpenes from the marine red alga Laurencia composita

Four new chamigrane derivatives, laurecomin A (1), laurecomin B (2), laurecomin C (3), and laurecomin D (4), one new naturally occurring sesquiterpene, 2,10-dibromo-3-chloro-7-chamigren-9-ol acetate (5), and three known halogenated structures, deoxyprepacifenol (6), 1-bromoselin-4(14),11-diene (7), and 9-bromoselin-4(14),11-diene (8), were isolated from the marine red alga Laurencia composita collected from Pingtan Island, China. The structures of these compounds were unambiguously established by 1D, 2D NMR and mass spectroscopic techniques. The bioassay results showed that 2 was active against both brine shrimp and fungus Colletotrichum lagenarium.

Halogenated chamigrane sesquiterpenes from Laurencia okamurae

Three new halogenated chamigrane sesquiterpenes, laurokamin A (1), laurokamin B (2), and laurokamin C (3), and four known halogenated chamigrane sesquiterpenes, 10‐bromo‐α‐chamigrene (4), 10‐bromo‐β‐chamigrene (5), 2,10‐dibromo‐3‐chloro‐β‐chamigrene (6), and obtusane (7), were isolated from the marine red alga Laurencia okamurae collected from the coast of Rongcheng, China. The structures of these compounds were unambiguously identified by one‐ and two‐dimensional NMR and mass spectroscopic methods. The antimicrobial activity of compounds 1–3 was evaluated. Copyright

Ergosteroid derivatives from an algicolous strain of Aspergillus ustus

One new ergosteroid derivative, isocyathisterol (1), and eight known compounds (2–9) were isolated from the culture of an algicolous strain (cf-42) of Aspergillus ustus obtained from the fresh tissue of marine green alga Codium fragile. The structure and absolute configuration of 1 were unequivocally identified by using NMR and mass spectroscopic methods as well as quantum chemical calculations. Compound 1 exhibited weak antibacterial activity.