The benzodiazepine sclerotigenin (auranthine B) recently described as a metabolite of Penicillium sclerotigenum, has been isolated as the major metabolite from an isolate of P. commune. The structure of sclerotigenin was established by a single-crystal X-ray diffraction study and by NMR spectroscopy. UV-guided screening for benzodiazepine production by other penicillia revealed that sclerotigenin was also produced by isolates of P. clavigerum, P. lanosum, P. melanoconidium, P. sclerotigenum and P. verrucosum. Sclerotigenin was detected both intra- and extracellularly. Apparently, P. aurantiogriseum is the only auranthine producing species in genus Penicillium.