Hydrazine hydrate (1:1) → 1-Ethyl-3-(7-hydrazinocarbonyl-5-pyridin-3-yl-benzothiazol-2-yl)-urea

Participants

Reaction Steps

A suspension of 2-(3-Ethyl-ureido)-5-pyridin-3-yl-benzothiazole-7-carboxylic acid methyl ester (319 mg, 0.895 mmol) in methanol (10 ml) was treated with hydrazine hydrate (2 ml) and stirred at ambient temperature for 16 h. HPLC indicated that the reaction mixture still contained a considerable amount of starter so a further 1 ml of hydrazine hydrate was added and the stirring continued for a further 24 h. The resultant mixture was diluted with water (50 ml) and the solid collected by filtration. This was washed with water (25 ml) followed by ethanol (25 ml) and dried in vacuo to give 1-Ethyl-3-(7-hydrazinocarbonyl-5-pyridin-3-yl-benzothiazol-2-yl)-urea as an off-white solid (312 mg, 98%).

Provenance & Evidence