PENITREMONES A-C, PENICILLIUM METABOLITES CONTAINING AN OXIDIZED PENITREM CARBON SKELETON GIVING INSIGHT INTO STRUCTURE TREMORGENIC RELATIONSHIPS

A new group of microbial metabolites, designated penitremones A-C, hav e been characterised by mass spectrometry and H-1 and C-13 NMR spectro scopy as 10-keto, 11,33-dihydro-variants of the penitrem, indole-isopr enoid skeleton. The principal metabolite penitremone A, produced with penitrem A by a Penicillium sp., is an isomer of penitrem E and was al so similarly tremorgenic. Reduction of the carbonyl of penitremones A and B with NaHB4 altered tremorgenic activity, thereby indicating pote ntial for new insights into structure-activity relationships in tremor genic mycotoxins, particularly with respect to neurological disorders in agricultural ruminants caused by the related keto-alkaloid lolitrem B.