Synthesis of pyrazolo[1,5‐a]‐, 1,2,4‐triazolo[1,5‐a]‐ and imidazo[1,2‐a]pyrimidines related to zaleplon,a new drug for the treatment of insomnia

This paper describes the preparation of some pyrazolo1,5‐a]‐, 1,2,4‐triazolo1,5‐a]‐ and imidazo1,2‐a]‐pyrimidines substituted on the pyrimidine moiety by a 4‐(N‐acetyl‐N‐ethyl)amino]phenyl group. A new synthesis of related benzoh]pyrazolo1,5‐a]‐, benzoh]pyrazolo5,1‐b]‐ and benzoh]1,2,4‐triazolo1,5‐a]‐quinazolines is also reported.