Neodolastane diterpenoids from cultures of basidiomycete hydropus cf. trichoderma

Abstract

A highly conjugated 17- nor -neodolastane diterpenoid possessing a nitrile group, hydropusin A ( 1 ), and a neodolastane, hydropusin B ( 2a / 2 b / 2c ), were isolated from cultures of the basidiomycete Hydropus cf. Trichoderma TBRC-BCC 43790. Hydropusin B was isolated as a mixture of three forms of interconvertible isomerization, which was supported by a deuteration experiment. Hydropusin A exhibited weak cytotoxicity to NCI–H187 and Vero cell-lines (IC<inf>50</inf> 60.6 and 64.5 μM, respectively), whereas hydropusin B showed antitubercular activity against Mycobacterium tuberculosis H37Ra (MIC 12.5 μg/mL).