ISOLATION, CHARACTERIZATION AND PARTIAL SYNTHESIS OF A MAJOR METABOLITE OF A POTENT BRONCHODILATOR ,10-TETRAHYDROAZEPINO[2,1-B]-QUINAZOLIN-12(6H)-ONE

Metabolic studies of a bronchodilator compound 9,10-tetrahydroazepino[ 2,1-b]quinazolin-12(6H)-one (1), RLX) have been carried out in Charles -Foster rats and rhesus monkeys. Five metaboites in total have been de tected on TLC plates from the rats as well as monkeys urine samples an d the major metabolite isolated has been assigned the structure as 9,1 0-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one (7) on the basis of IR , H-1-NMR, C-13-NMR and mass spectral data. The structure of this majo r metabolite has been further confirmed by its partial synthesis (Sche me I). The bronchodilatory activity of the compound (7) has been compa red with the parent compound and standard drugs.