HETEROCYCLIC DERIVATIVES OF PYRIDAZINONE, THIADIAZINONE, OXADIAZINONE AND TRIAZINONE

摘要

ABSTRACTHeterocyclic CompoundsHeterocyclic compounds of the formula:-wherein A is a direct link, or is alkylene of 1 to 4carbon atoms or alkenylene of 2 to 4 carbon atoms;wherein either X is -CR1R2- and Y is -O-, -S- or-NR3-, wheren R1, R2 and R3, which may be thesame or different, each is hydrogen or alkyl of up to4 carbon atoms;or X is -O-, -S- or -NH- and Y is -CR1R2- whereinR1 and R2 have the meanings stated above;and wherein Het is a 5- or 6- membered heterocyclic ringcontaining 1, 2 or 3 heteroatoms selected from nitrogen,oxygen or sulphur atoms, which ring may be unsubstitutedor may bear one or two substituents as set out in claim1, provided that when X is -CR1R2- and A is a directlink, Het is not unsubstituted 2-furyl; and saltsthereof where appropriate; processes for theirmanufacture and pharmaceutical compositions containingthem. The compounds possess cardiotonic and/orantihypertensive activity.