Study On Secondary Metabolites Of Three Marine Actinomycetes

In order to find bioactive compounds with unique structures from actinomycetes, three marine actinomycetes(Streptomyce sp. 10355, Micrococcus sp. R21, and ActiNomadura sp.4388)were collected and subjected to systematic investigation for the secondary metabolites.Sixteen compounds were isolated from the ethyl acetate extracts by silica gel column,sephadex LH-20 column and MPLC, their structures were elucidated by NMR and comparison of chemical and physical data with authentic samples reported in literatures. As a result:1. One novel sesquiterpene was obtained from a marine actinomycete Streptomyce sp.10355, and was given a name of(1R,R,4S,5S,8S,10S)-4,9,9,10-tetramethyl-2, 5, 10-trihydroxytricyclo [6.2.1.01, 5]undecan(1). And it showed moderate inhibitory activity against lipopolysaccharide-induced TNFα production in RAW264.7 macrophages.2. Eight compounds were obtained from the marine actinomycetes Micrococcus sp. R21.By mainly detailed analysis of their NMR data, their structures were elucidated as2-hydroxybenzoic acid(2), phenylacetic acid(3), cyclo(D-Pro-L-Leu)(4), dibutyl phthalate(5), N-β-acetyltryptamine(6), cyclo(L-Pro-L-Ala)(7), cyclo(4-hydroxy-L-Pro-L-leu)(8), and cyclo(L-Pro-L-Gly)(9).3. Seven compounds were obtained from ActiNomadura sp. 4388. Their structures were determined as(3Z, 6E)-1-N-methyl-3-benzylidene-6-isobutylidene-2,5-piperazinedione(10),(3Z,6E)-1-N-methyl-3-benzylidene-6-(2S-methyl-3-hydroxypropylidene)-2,5-piperazinedioe(11), pyrrole-2-carboxylic acid(12), 2,4,4a,8-tetrahydro-2,6,8-trimethyl-4a-(2-oxopropyl)pyrimido[5,4-e]-1,2,4-triazine-3,5,7(6H)-trione(13), 2, 5, 7-trimethyl-2,7-dihydro-5H-imidazo[4,5-e]-1,2,4-triazine-3,6-dione(14), cyclo(4-trans-L hydroxyPro-L-Phe)(15), and cyclo(gly-L-Leu)(16).Sixteen compounds were isolated and elucidated from three marine actinomycetes.Compound 1 is a novel stepsesquitriol, compounds 2、3、5、6、8、9were isolated from theMicrococcus sp. for the frist time and compounds 10~16 were isolated from the ActiNomadura sp. for the frist time.