Method B. 6-Methyl-g-(phenylhydrazon0)-6, 7, 8, 9-tetra-hydro-4H-pyrido [1, 2-a] pyrimidine- 3-carboxamide (12). To a solution of 9-(pheny1hydrazono) pyridopyrimidine 8 (10 mmol) in ethanol (25 mL) was added concentrated aqueous ammonium hydroxide (30 mL). After 1 day the precipitated carboxamide (12) was filtered off, dried, and recrystallized.
