Emestrins: Anti-Cryptococcus Epipolythiodioxopiperazines from Podospora australis

Eleven emestrin-type epipolythiodioxo­piperazines, including four new compounds, emestrins H–K (1–4), were isolated from the crude extracts of two strains of the coprophilous fungus Podospora australis. The structures of 1–4 were established primarily by analysis of NMR data, and the absolute configuration of C-6 in 1 was independently assigned using the modified Mosher method. Four of the known emestrins obtained (emestrins C–E and MPC1001C) were found to selectively inhibit the growth of Cryptococcus neoformans. These results also represent the first report of chemistry from any strain of P. australis.