Hydrazine hydrate (1:1) → HCID 19909619, compound

Participants

Reaction Steps

4-Chloro-6,7-dihydro-2-ethyl-8-methylpyrimido-[5,4-b][1,4]thiazin-7-one from Example 119 (2.4 g, 9.93 mmole) was suspended in approximately 100 ml of n-butanol. Hydrazine monohydrate (0.99 g, 19.9 mmole) was added and the resultant mixture was refluxed for about 20 hours. The reaction mixture was allowed to cool and the precipitate was separated by filtration, washed with water and dried, providing 1.93 g (81%) of 6,7-dihydro-2-ethyl-4-hydrazino-8-methylpyrimido [5,4-b][1,4]thiazin-7-one. Infrared and nuclear magnetic resonance spectral analyses confirmed the structural assignment.

Provenance & Evidence