Oxidation of the bisdihydrofuran moieties of aflatoxin B1 and sterigmatocystin; conformation of tetrahydrofurobenzofurans

Abstract

Attempts to prepare and isolate the products of epoxidation of the vinyl ether moieties of the two metabolites aflatoxin B₁(1) and sterigmatocystin (2) gave only trans-glycol derivatives. The rates of consumption of peroxy-acid in the presence of compounds (1) and (2) were measured. Aflatoxin B₁ dichloride and dibromide were prepared and their susceptibilities to nucleophilic attack were examined. The conformations of various di-substituted tetrahydrofurobenzofuran derivatives obtained were studied by ¹H n.m.r. spectroscopy.