HCID 136463927, compound → HCID 136425302, compound

Participants

Reaction Steps

A suspension of 25.7 g (0.10 mole) of 1-methyl-pyrazolo[1,5-c]quinazolin-5(6H)-one-2-carboxylic acid ethyl ester in 2.5 l of 10% alcoholic potassium hydroxide is refluxed for 3 hours, cooled to room temperature and filtered. The solid is dissolved in water extracted with chloroform, treated with Norit-A and filtered. The filtrate is cooled in an ice bath and acidified (Congo red) with 25 ml of concentrated hydrochloric acid. The white precipitate is filtered, digested with 1 l. of hot water and filtered, and dried to give the title compound.

Provenance & Evidence