| 摘要 |
A process for preparation of 3-amino-5,7-dimethyl-4,5,6,7-tetrahydro-2Н-pyrrazolo-[3,4-d]pyrimidine-4,6-dione of formulainvolves interaction of 1,3-N,N-dimethyl barbituric acid with formylating mixture of phosphorus oxychloride and dimethylformamide in a ratio of 2.7:1.1M, successive holding of reaction mixture for 50-60 minutes at room temperature of 20-25°С, for 50-60 minutes at 95±5 °Сand 50-60 minutes at 95±5 °Сand interaction of held reaction mixture with hydroxylamine hydrochloride. Prepared 6-chloro-1,3-dimethyluracil-5-carbonitryl is condensed with hydrazine hydrate in alcohol medium–the process is carried out during the time required for full termination of the reaction and formation of 3-amino-5,7-dimethyl-4,5,6,7-tetrahydro-2H-pyrrazolo[3,4-d]pyrimidine-4,6-dione. The process proposed allows to simplify the process considerably, decrease its durability, increase output and quality of the end product. |
