Iizukines C-E from a saline soil fungus Aspergillus iizukae.
Bioorg Chem. 2019 Jul 31;91:103167
Authors: Kang HH, Zhong MJ, Ma LY, Rong XG, Liu DS, Liu WZ
Three new alkaloids, iizukines C-E (1-3), including two aspochalasins (1 and 2), and one brasiliamide derivative (3), along with two known aspochalasins, rosellichalasin (4) and cytochalasin Z17 (5), were isolated from the culture of Aspergillus iizukae. Compound 1 was the first aspochalasin uniquely featuring a 1,2,4-triazole functionality, and 3 showed a pair of NMR signals in CDCl3 with a ratio of about 2:1 due to the existence of conformational isomers. Their structures were determined by extensive spectroscopic analyses and single-crystal X-ray diffractions. In particular, the 1,2,4-triazole moiety in 1 was assigned on the basis of extremely valuable 1H-15N HMBC spectrum. Compound 1 exhibited cytotoxic effect towards HL-60 and A549 cell lines with IC50 values of 3.8 and 7.2 μM, respectively.
PMID: 31398599 [PubMed – as supplied by publisher]