Inotropic 'A' ring substituted sulmazole and isomazole analogues

Article abstract of DOI:10.1021/jm00170a030

A series of 'A' ring substituted sulmazole and isomazole analogues have been prepared and evaluated as inotropic agents. pK(A)'s, protonation sites, and log P values were measured for selected compounds and their electronic properties were calculated. No simple correlation between inotropic activity and pK(A), protonation site, or log P value was observed. However, in vitro inotropism did correlate with the calculated charge density of the 'B' ring imidazo nitrogen atom. The 6-position of sulmazole appeared to be the most tolerant toward substituents, th 6-amino derivative 7 being a more potent inotrope than sulmazole itself. 4-Methoxyisomazole 13 had comparable in vivo inotropic properties to those of isomazole.