Synthesis of Aza Analogs of Amrinone

The aldol condensation product (4) of L-acerylpyridine (2) and diechyl mesaxalate (3) was converted to pyridarinecarboxylic acid hydraride (6).Curtius reacrion of 6 gave aminopyridazinone (7).The condensation of (4-pyridiny1)glyoxal (17) with aminomalonarnide (9) yielded pyrazinecarboxamide (18) which war transformed to aminopyrarinone (19) by the ~ofmann reaction.Curtius reaction of l,Z,L-rriarinone~5-c~rbbxylic acid (Zlb) gave aminotriarinane (22).Demethylation of mer,hoxypyrimidine (29) prepared from methyl 2-methoxyfarmylacetare (25) and isonicorinamidine (26) gave pyrimidinol (301.Several years ago, the search for a nonglycoside cardiotonic agent in our laboratory led to the development of anrinane our continuing efforts to find an orally accive and a mare potent agent have led ro the design and synthesis of several aza analogs of 1.The replacement of 2(1H)-pyridinone moiety of 1 by pyridazine, pyrazine, 1,2,4-criazine and pyrimidine ring systems has resulted in the synthesis of 7, 19.22 and 30, respect;ively.The preparation of these compounds required the synthesis of novel intermediates depicted in schemes A, B.