Progress in research on active metabolites of fungi from sedimentary environment

Recently, Dr Zhong Weimao and his team from South China Sea Institute of Oceanography, Chinese Academy of Sciences, cooperated with South China Botanical Garden of Chinese Academy of Sciences, Guangdong Institute of Microbiology and Guangzhou University of traditional Chinese medicine and other researchers to make new progress in the research of active metabolites of fungi from the sedimentary environment of South China Sea Relevant achievements were published in organic letters (DOI: 10.1021/acs.orglett.8b01880) and marine drugs (DOI: 10.3390/md16040136) Three pairs of enantiomers, variecolor tins a-c (1-3), were isolated from Eurotium sp SCSIO f452 from the South China Sea sedimentary environment by Zhong Weimao and his team Compound 1 has a novel split ring anthronopyranoid Compounds 2 and 3 have a new 6 / 6 / 6 / 6 tetracycline anthrone structure skeleton These compounds are derived from indole diketone piperazine alkaloids and anthraquinone, but their structures are different from the four reported variecolor tides with pyrano anthrone skeleton Using NMR, MS and X-ray single crystal diffraction techniques, the plane and relative structures of the novel structure of variecolor tins a-c (1-3) were determined The optical rotation and circular dichroism suggested that compound 1-3 may exist in the form of racemate The absolute configuration of all compounds was determined by chiral resolution and ECD quantum chemistry calculation The results of antioxidative and cytotoxic tests showed that the antioxidative activity of (-) - 1 was nearly three times that of (±) - 1, (+) - 2 and (+) - 3 had certain SF-268 and HepG2 cytotoxic activities, but (±) - 2 and (±) - 3 had no activity, so it was speculated that the absolute configuration of the compound had a certain influence on its activity The preliminary study of docking shows that the difference of enantiomers activity may be related to their hydrophobic interaction with potential targets and the formation of hydrogen bonds The above research results are published in organizational letters In addition, four new indole alkaloids (4-7), a new biphenylpyrimidine derivative (17) and a series of other indole Dione piperazines (8-16) were also found in the strain Compounds 4 and 5 are a pair of epiisomers with hexahydropyrrolo [2,3-b] indole framework Compounds 17 are rare in marine natural products, which are mostly found in chemical synthesis products Compounds 6, 8-10, 13 and 15 showed higher antioxidant activity than VC The research was published in marine drugs Zhong Weimao is the first author of the above two papers The research work has been supported by the national key R & D plan, the National Natural Science Foundation and the science and technology plan of Guangdong Province.