Isolierung und Strukturaufklärung von Ergokonin A und B; zwei neue antifungische Sterol‐Antibiotika aus Trichoderma koningii

Isolation and Structure Elucidation of Ergokonin A and B; Two New Antifungal Sterol Antibiotics from Trichoderma koningii Isolation and structure elucidation by 2D‐NMR spectroscopy of the two new antifungal sterol antibiotics ergokonin A (1) and B (2a) from Trichoderma koningii are described. The structures of 1 and 2a are derived from ergosterol and characterized by an 18‐carboxy group. In addition ergokonin A (1) is esterified at the 3‐hydroxy group with (2S,3S)‐3‐hydroxyleucine 3‐O‐sulfate (3c). In the course of structure elucidation of the amino acid residue the stereoisomers of 3‐hydroxyleucine N‐sulfamate and 3‐O‐sulfate (3b, c) have been synthesized and characterized by NMR spectroscopy.