SYNTHESIS AND PROPERTIES OF MESOIONIC PYRIMIDO[1,2-B]PYRIDAZINE-2,4-DIONES AND MESOIONIC PYRIDAZINO[2,3-A]-S-TRIAZINE-2,4-DIONES - MESOIONIC ANALOGS STRUCTURALLY RELATED TO FERVENULIN

Derivatives of 2 new and unusual classes of heterocycles, possessing structural similarities to the broad spectrum antibiotic fervenulin, were synthesized and examined for in vitro antimicrobial activity. Only 3 of 17 mesoionic pyrimido[1,2-b]pyridazine-2,4-diones exhibited evidence of antimicrobial activity while 7 of 8 mesoionic pyridazino[2,3-a]-s-triazine-2,4-diones were active against 1 or more microorganisms [Serratia marcescens, Staphylococcus aureus, S. epidermidis, Candida albicans, Plasmodium berghei]. Susceptibility toward attack by nucleophiles of both mesoionic pyridazino[2,3-a]-s-triazine-2,4-diones and fervenulin was observed.