α-Pyrones with Diverse Hydroxy Substitutions from Three Marine-Derived Nocardiopsis Strains.
Eight new α-pyrones 1-8 and three known α-pyrones 9-11 were isolated from three marine-derived Nocardiopsis strains SCSIO 10419, SCSIO 04583, and SCSIO KS107. The structures of compounds 1-8 were elucidated by comprehensive spectral analyses. The absolute configurations of 4-deoxyphomapyrone C (1), 4-deoxy-11-hydroxyphomapyrone C (3), 4-deoxy-7R-hydroxyphomapyrone C (5), and phomapyrone C (11) were determined by TDDFT-ECD calculations for the solution conformers, which revealed that the conformation of the side chain was decisive for the sign of the characteristic high-wavelength ECD transition. (-)-4-Deoxy-8-hydroxyphomapyrone C (4) was isolated from SCSIO 10419 and was deduced as a diastereomeric mixture containing (8S)- and (8R)-4-deoxy-8-hydroxyphomapyrone C in a ratio of 2.6:1 (8R:8S), by chiral-phase HPLC analysis and Mosher's ester analysis. Interestingly, 7-hydroxymucidone (9) was isolated from both SCSIO 04583 and SCSIO KS107, as an enantiomeric mixture containing (7S)-hydroxymucidone (major in 9 from SCSIO 04583) and (7R)-hydroxymucidone (major in 9 from SCSIO KS107). α-Pyrones 3-5 were identified as three isomers of phomapyrone C (11) with diverse hydroxy substitutions. α-Pyrones 10-hydroxymucidone (6), 4-hydroxymucidone (8), and 9, differed in the position of the hydroxy group. Several α-pyrones exhibited moderate growth inhibitory activity against Micrococcus luteus and Bacillus subtilis.
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences , 164 West Xingang Road, Guangzhou 510301, China.
Haibo
H
Zhang
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences , 164 West Xingang Road, Guangzhou 510301, China.
Kumar
K
Saurav
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences , 164 West Xingang Road, Guangzhou 510301, China.|School of Life Sciences, Hunan Normal University , 36 Lushan Road, Changsha 410081, China.
Ziquan
Z
Yu
Department of Organic Chemistry, University of Debrecen , P.O. Box 400, H-4002 Debrecen, Hungary.
Attila
A
Mándi
Department of Organic Chemistry, University of Debrecen , P.O. Box 400, H-4002 Debrecen, Hungary.
Tibor
T
Kurtán
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences , 164 West Xingang Road, Guangzhou 510301, China.
Jie
J
Li
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences , 164 West Xingang Road, Guangzhou 510301, China.
Xinpeng
X
Tian
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences , 164 West Xingang Road, Guangzhou 510301, China.
Qingbo
Q
Zhang
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences , 164 West Xingang Road, Guangzhou 510301, China.
Wenjun
W
Zhang
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences , 164 West Xingang Road, Guangzhou 510301, China.
Changsheng
C
Zhang
D000192:Actinomycetales / Q000737:chemistry*; D001407:Bacillus / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D013293:Enterococcus faecalis / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D008386:Marine Biology; D008826:Microbial Sensitivity Tests; D016982:Micrococcus luteus / Q000187:drug effects; D008968:Molecular Conformation; D015394:Molecular Structure; D011753:Pyrones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects; D013237:Stereoisomerism
D011753:Pyrones