Accraspiroketides A-B, Phenylnaphthacenoid-Derived Polyketides with Unprecedented [6 + 6+6 + 6] + [5 + 5] Spiro-Architecture
Authors
Fleurdeliz Maglangit
Department of Biology and Environmental Science, College of Science, University of the Philippines Cebu
Shan Wang
Arvin Moser
Kwaku Kyeremeh
Laurent Trembleau
Yongjun Zhou
David James Clark
Jioji Tabudravu
Hai Deng
Abstract
Two novel polyketides, accraspiroketides A (1) and B (2), which feature unprecedented [6 + 6+6 + 6] + [5 + 5] spiro chemical architectures, were isolated from Streptomyces sp. MA37 ΔaccJ mutant strain. Compounds 1-2 exhibit excellent activity against Gram-positive bacteria (MIC = 1.5–6.3 μg/mL). Notably, 1 and 2 have superior activity against clinically isolated Enterococcus faecium K60–39 (MIC = 4.0 μg/mL and 4.7 μg/mL, respectively) than ampicillin (MIC = 25 μg/mL).