IH-IMIDAZO(4,5-B)PYRAZINE-2-ONES AND PROCESS FOR PREPARING

摘要

1,246,006. Diuretic &c compositions. MERCK & CO. Inc. 17 Nov., 1969 [20 Nov., 1968], No. 56181/69. Heading A5B. [Also in Division C2] Pharmaceutical compositions having anti-hypertensive, diuretic and saluretic activity comprise, as active ingredient, a 5-amino-6-chloro- 1H-imidazo [4, 5-6] pyrazin-2-one of the general formula: wherein R1 is a hydrogen atom or a C 3-7 cycloalkyl, phenyl, C 1-5 alkyl-amidino, C 2-6 alkanoyl-amidino, C 3-5 alkynyl or C 3-5 alkenyl group or a C 1-6 alkyl group optionally substituted by one or more hydroxy, C 1-3 alkoxy, pyridyl, phenyl, halo phenyl and/or -NR5R6 groups, in which R5 is a hydrogen atom or a C 1-5 alkyl, acetyl or propionyl group and R6 is a hydrogen atom or a C 1-5 alkyl group or R5R6N is a saturated 5-6 membered heterocyclic ring optionally containing an imino or C 1-5 alkylimino group or an oxygen atom, and R2 is a hydrogen atom or a C 1-3 alkyl group or R1R2N is defined as R5R6N, or R1 and R2 are together a bis (dimethylamino)-methylene group, together with an inert carrier, diluent or coating, and may be administered orally or parenterally as pills, tablets, capsules, elixirs and injeotable preparations.