Synthesis of some new fused coumarin derivatives

2-Hydrazino-4-hydroxy-5H-[1]-benzopyrano-[4, 3-d]-pyrimidin-5-one (3) was p repared via condensation of 2 with hydrazine hydrate. Treatment of 3 with m ethylene chloride, ethyl chloroformate, ethyl chloroacetate and benzaldehyd e yielded the corresponding 2 - ( substituted) hydrazino - 4 - hydro-xy-5H- [1]-benzopyrano-[4, 3-d]-pyrimidin-5-one (4, 5, 6, and 10), followed by cyc lization of 4, 5 and 6 with dimethyl formamide and fused sodium acetate und er reflux, while compound 10 was cyclized with bromine and sodium acetate i n acetic acid. Compound 3 reacted with beta-(toloyl) acrylic acid, ethyl al pha-cyano-p-methoxycinnamate, diethyl malonate and acetyl chloride affordin g the corresponding 2-(substituted) hydrazino-4-hydroxy-5H-[1]-benzopyrano- [4, 3-d]-pyrimidin-5-one (12, 13, 14, 15 and 16).