Cinereain: A Novel Metabolite with Plant Growth Regulating Properties from Botrytis cinerea

Botrytis cinerea, which was isolated from the surface of stored sunflower seed, produced a novel biologically active natural product when cultured on shredded wheat medium. The metabolite, trivially named cinereain, was a ruby red crystalline product with the molecular formula C18H21N3O3 and melting point 201~203°C. The structure was unequivocally established by single crystal X-ray diffraction; UV, IR, NMR (1H and 13C) and mass spectrometry supported the crystallographic data. Cinereain significantly inhibited the growth of etiolated wheat. coleoptiles (p < 0.01) at 10-3 and 10-4 m in bioassays. No effects were noted on treated intact greenhousegrown bean and tobacco plants, but there was mild necrosis and chlorosis in corn.