title: Antimycins A(19) and A(20), two new antimycins produced by marine actinomycete Streptomyces antibioticus H74-18.
abstract: Two new antimycin antibiotics; that is antimycins A(19) (1) and A(20) (2), were isolated from a cultured broth of marine actinomycete Streptomyces antibioticus H74-18 together with antimycins A(1a) (3a) and A(1b) (3b), A(2a) (4), A(3a) (5a) and A(3b) (5b). Their structures were determined by spectroscopic methods in combination with X-ray diffraction. Antimycin A(19) possessed a chiral acyl chain and an alkyl branch. The absolute configuration of chiral acyl chain in 1 was determined by X-ray diffraction analysis. Antimycin A(20) (2) has the shortest and simplest acetoxy acyl chain in the antimycins family. All the antimycins (1-5) showed potential antifungal activities against Candida albicans with MIC of about 5-10 μg ml(-1).
authors.affiliation: Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou, China.
authors.forename: Lin-Ya
authors.initials: LY
authors.lastname: Xu
authors.forename: Xue-Sheng
authors.initials: XS
authors.lastname: Quan
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.forename: Hui-Fang
authors.initials: HF
authors.lastname: Sheng
authors.forename: Guang-Xiong
authors.initials: GX
authors.lastname: Zhou
authors.forename: Bi-Run
authors.initials: BR
authors.lastname: Lin
authors.forename: Ren-Wang
authors.initials: RW
authors.lastname: Jiang
authors.forename: Xin-Sheng
authors.initials: XS
authors.lastname: Yao