Water → HCID 135767960, compound

Participants

Reaction Conditions

Reaction Steps

7-Aminocephalosporanic acid (272 mg) and 272 mg of the above 4-(7-mercaptopyrazolo[1,5-a]pyrimidin-5-yl)pyrocatechol are suspended in a mixture of 2 ml of sulpholane and 2 ml of dichloromethane. 0.75 ml of boron trifluoride etherate is added thereto and the mixture is stirred at 25° C. for 5 hours. Thereafter, it is treated with 20 ml of water, the aqueous phase is separated, its pH is adjusted to 3.5 using concentrated aqueous amonia solution and the precipitated product is filtered off under suction, washed with water, methanol and finally with diethyl ether and dried at 0.1 mmHg and 40° C. There are obtained 350 mg of (6R,7R)-7-amino-3-[[[5-(3,4-dihydroxyphenyl)pyrazolo[1,5-a]pyrimidin-7yl]thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid.

Provenance & Evidence