TY - JOUR A1 - Saito, Shun A1 - Indo, Kanji A1 - Oku, Naoya A1 - Komaki, Hisayuki A1 - Kawasaki, Masashi A1 - Igarashi, Yasuhiro T1 - Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes JF - Beilstein Archives Y1 - 2021/// SN - M3 - doi:10.3762/bxiv.2021.74.v1 N2 - A genome mining survey combined with metabolome analysis of publicly available strains identified Couchioplanessp. RD010705, a strain belonging to an underexplored genus of rare actinomycetes, as a producer of new metabolites. HPLC-DAD-guided fractionation of its fermentation extracts resulted in the isolation of five new methyl-branched unsaturated fatty acids, (2E,4E)-2,4-dimethyl-2,4-octadienoic acid (1), (2E,4E)-2,4,7-trimethyl-2,4-octadienoic acid (2), (R)-(–)-phialomustin B (3), (2E,4E)-7-hydroxy-2,4-dimethyl-2,4-octadienoic acid (4), (2E,4E)-7-hydroxy-2,4,7-trimethyl-2,4-octadienoic acid (5), and one prenylated tryptophan derivative, 6-(3,3-dimethylallyl)-N-acetyl-L-tryptophan (6). The enantiomer ratio of 4 was determined to be approximately S/R = 56/44 by a recursive application of Trost’s chiral anisotropy analysis and chiral HPLC analysis of its methyl ester. Compounds 1–5 were weakly inhibitory against Kocuria rhizophila at MIC 100 mg/mL and none were cytotoxic against P388 at the same concentration. ER -