Tandem Amidation Catalysis In The Synthesis Of Diazaphenoxazinecarboxamides Of Pharmaceutical Interest

ABSTRACT

Tandem amidation catalyzed synthesis of linear diazaphenoxazine carboxamide derivatives is reported. This was

achieved by the reaction of 2-amino-3-hydroxypyridine and 2,3,5-trichloropyridine in aqueous basic medium which

gave 3-chloro-1,9-diazaphenoxazine as white solid crystals. 3-Chloro-1,9-diazaphenoxazine was then subjected to

Buchwald-Hartwig amidation coupling reaction with various amides namely formamide, phthalamide, 4-

nitrobenzamide, benzamide and acetamide via water promoted catalyst preactivation protocol to afford the

following, 3-amido derivatives of 1,9-diazaphenoxazine namely 3-formamido-1,9-diazaphenoxazine, 3-

phthalamido-1,9-diazaphenoxazine, 3-(4-nitrobenamido)-1,9-diazaphenoxazine, 3-benzamido-1,9-

diazaphenoxazine and 3-acetamido-1,9-diazaphenoxazine. The compounds were characterized using UV-visible,

FTIR, 1HNMR and 13CNMR spectroscopy.