BENZOMALVIN-D, A NEW 1,4-BENZODIAZEPINE ATROPISOMER

A new compound, benzomalvin D [5], isolated from a fungal culture of P enicillium sp., is an atropisomer of the previously reported benzomalv in A [1]. Benzomalvins A [1] and D [5] interconvert to form a 4:1 mixt ure at room temperature and are totally separable by hplc. This equili brium phenomenon was further explored through total synthesis of benzo malvin A [1] and related compounds, leading ro the first report of nat ural atropisomers of 1,4-benzodiazepines.