反应详情

7-ACA (1.36 g., 5 mmoles) was added at 50° C. to a solution of 6-mercapto-2,3-dihydro-s-triazolo[4,3-b]pyridazin-3-one (0.84 g., 5 mmoles) and sodium bicarbonate (0.84 g., 10 mmoles) in 20 ml. of 0.1 M phosphate buffer solution (pH 6.4) and the mixture was heated for 2 hours at 70° C. A small amount of insoluble material was removed by filtration and acidification of the filtrate to pH 5 with dil. HCl afforded the product 4e which was collected by filtration, washed with water (30 ml.) and dried in vacuo on P2O5. Yield of 7-amino-3-[2,3-dihydro-3-triazolo(4,3-b)pyridazin-3-one-6-ylthiomethyl]-3-cephem-4-carboxylic acid 1.25 g. (66%), M.p. > 300° C.

1. customA small amount of insoluble material was removed by filtration and acidification of the filtrate to pH 5 with dil. HCl