Condensed heterotricycles: potential metabolites of dibenz[b,f][I,4]oxazepine antidepressant, sintamil

Abstract

The synthesis of several potential metabolites of the antidepressant, Sintamil (1) is described. Nitrolactams 3, 6 and 10, aminolactams 4, 7 and 11, and the aminoalkyl derivatives 8, 9, 12 and 13 have been described before [Indian J. Chem., 12 (T974), 227]. Treatment of 1 with H₂O₂ gave the N-oxide 2. Several syntheses of the desmethyl derivative 5 have been achieved : alkylation of 3 with N-(3-chloropropyl)-N-methylformamide followed by hydrolysis; demethylation of 1 with CNBr, followed by acid cleavage of the cyano group in 15 and with ethyl chloroformate, followed by treatment with HBr in acetic acid. Treatment of the intermediate urethane 16 from the last reaction with alcoholic alkali afforded the ring cleaved product 17. The methylaminopropyl lactam 5 was converted into the acetate 18 and urea 19. It was also reduced to the diamine 20. . Treatment of the chlorolactam 14 with the sodium salt of p-toluenesulphonamide led to thV derivative 21. Alkali-catalysed addition of lactam 3 to acrylonitrile gave 22; addition to methyl acrylate gave the ester 23 which was hydrolysed to the acid 24 on the one hand and reduced to the amino ester 28 on the other. Propionitrile 25 and propionic ester 26 were similarly prepared. N-(2-Chloro-5-nitrobenzoyl)-4-benzyloxy-2-hydroxyaniline (30) was cyclized to the lactam 31, which was aminoalkylated to 32. Treatment of 32 with hot acid cleaved the benzyl group to afford the phenolic lactam 33.