Читать книгу Routes to Essential Medicines - Peter J. Harrington - Страница 20

Antineoplastics and Immunosuppressives/Cytotoxic and Adjuvant Medicines

Medicines for Diseases of Joints/Medicines Used to Treat Gout

Hydrazine is often the source of the two nitrogen atoms in a pyrazole ring.

Discussion. The pyrimidine ring of the pyrazolo[3,4‐d]pyrimidine is formed in the final step by reaction of 3‐aminopyrazole‐4‐carboxamide with formamide. The pyrazole ring is formed from 2‐cyano‐3‐morpholinoacrylamide and hydrazine. The enamine of 2‐cyano‐3‐morpholinoacrylamide is formed from the enol ether by the displacement of ethanol by morpholine. The enol ether of 2‐cyano‐3‐ethoxyacrylamide is formed by the reaction of 2‐cyanoacetamide with triethyl orthoformate.