Thioamycolamides A-E, Sulfur-Containing Cycliclipopeptides Produced by the Rare Actinomycete sp.

A series of novel sulfur-containing cycliclipopeptides named thioamycolamides A-E, with thiazoline, thioether rings, and fatty acid moieties, were identified from the culture broth of the rare actinomycete sp. 26-4. The planar structural elucidation was accomplished by HRMS and 1D/2D NMR spectroscopic data analyses. The absolute configurations were unambiguously determined by Marfey's method, CD spectroscopy, and synthesis of partial structures. Moreover, their growth inhibitory activities against human tumor cell lines were investigated.