RESUMEN
Glutarimide-containing polyketides usually exhibit anti-fungi activity, which was well exampled by cycloheximide. In our work, three new polyketide structures, 12-amidestreptimidone (1), 12-carboxylstreptimidone (2) and 3-(5S,8R)-(2-amino-2-oxoethyl-2'-methoxy-2'-oxoethyl)-8,10-dimethyl-7-oxododeca-5-hydroxy-9E,11-diolefin (3) were isolated from Streptomyces sp. JCM 4793. 3 without the glutarimide moiety is not active against fungi as expected, while 1 bearing the amide moiety is much more active than its carboxylic form 2. Here we report the isolation, structural elucidation, antifungal activity, and proposed biosynthesis pathway of 1-3.
Asunto(s)
Antifúngicos , Policétidos , Streptomyces , Streptomyces/metabolismo , Streptomyces/química , Policétidos/farmacología , Policétidos/química , Policétidos/aislamiento & purificación , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana , Piperidonas/farmacología , Piperidonas/química , Piperidonas/aislamiento & purificación , Estructura MolecularRESUMEN
Five new toosendanin limonoids with highly oxidative furan ring walsurobustones A-D (1-4), and one new furan ring degraded limonoid walsurobustone E (5) together with one known compound toonapubesic acid B (6) were isolated from the leaves of Walsura robusta. Their structures were elucidated by NMR and MS data. Especially, the absolute configuration of toonapubesic acid B (6) was confirmed by X-ray diffraction study. Compounds 1-6 exhibited good cytotoxicity against the cancer cell lines HL-60, SMMC-7721, A-549, MCF-7, and SW480.
