UV-guided isolation of verrucine A and B, novel quinazolines from Penicillium verrucosum structurally related to anacine from P. aurantiogriseum

Two novel quinazolines, verrucine A and B, have been isolated as a major and a minor metabolite of Penicillium verrucosum, respectively. Both are condensates of one mole each of anthranilic acid, phenylalanine and glutamine. The structures were elucidated by spectroscopic methods and the two compounds were found to be epimers. The spectroscopic data for the ostensible benzodiazepine anacine reported from Penicillium aurantiogriseum, composed of one mole each of anthranilic acid, leucine and glutamine, appeared very similar to those of verrucine A. Therefore a revised quinazoline structure for anacine is proposed.