Highly Conjugated Ergostane‐Type Steroids and Aranotin‐Type Diketopiperazines from the Fungus Aspergillus terreus BCC 4651

Abstract Two new ergostane derivatives, 12 β ,15 α ,25,26‐tetrahydroxyergosta‐4,6,8(14),22‐tetraen‐3‐one ( 1 ) and 12 β ,15 α ,25,28‐tetrahydroxyergosta‐4,6,8(14),22‐tetraen‐3‐one ( 2 ), and a new aranotin‐type diketopiperazine, bisdethiobis(methylsulfanyl)apoaranotin ( 3 ), were isolated from the fungus Aspergillus terreus BCC 4651. The structures of the new compounds were elucidated by means of NMR spectroscopic and MS analyses.