Anti-Respiratory Syncytial Virus Prenylated Dihydroquinolone Derivatives from the Gorgonian-Derived Fungus <i>Aspergillus</i> sp. XS-20090B15
作者:Min Chen、Chang-Lun Shao、Hong Meng、Zhi-Gang She、Chang-Yun Wang
DOI:10.1021/np500650t
日期:2014.12.26
Two new prenylated dihydroquinolone derivatives, 22-O-(N-Me-l-valyl)aflaquinolone B (1) and 22-O-(N-Me-l-valyl)-21-epi-aflaquinolone B (2), and two known analogues, aflaquinolones A (3) and D (or a diastereomer of D, 4), were isolated from the mycelia of a gorgonian-derived Aspergillus sp. fungus. The structures of the new compounds were elucidated by spectroscopic methods, ECD spectra, Marfey's method, and chemical conversion. Compounds 1 and 2 display an unusual esterification of N-Me-l-Val to the side-chain prenyl group. Compound 2 exhibited outstanding anti-RSV activity with an IC50 value of 42 nM, approximately 500-fold stronger than that of the positive control ribavirin (IC50 = 20 μM), and showed a comparatively higher therapeutic ratio (TC50/IC50 = 520).