(S)-2-(4-Chlorobenzoyl)-1,2,3,4-tetrahydrobenzo[e]pyrazino[1,2-a][1,4]diazepine-6,12(11H,12aH)-dione—Synthesis and Crystallographic Studies

(S)-2-(4-Chlorobenzoyl)-1,2,3,4-tetrahydrobenzo[e]pyrazino[1,2-a][1,4]diazepine-6,12(11H,12aH)-dione was obtained in a three-step, one-pot synthesis, starting from optically pure(S)-2-piperazine carboxylic acid dihydrochloride. Selective acylation of theβ-nitrogen atom followedby condensation with isatoic anhydride and cyclization with HATU/DIPEA to a seven-memberbenzodiazepine ring, led to the tricyclic benzodiazepine derivative. Crystallographic studies andinitial biological screening were performed for the title compound.