Synthesis of novel pyrido[4,3-e][1,2,4]triazino[3,2-c][1,2,4] thiadiazine 6,6-dioxide derivatives with potential anticancer activity

Abstract

A series of novel 3-/2,3-substituted pyrido[4,3-e][1,2,4]triazino[3,2-c][1,2,4]thiadiazine 6,6-dioxides 4-28 have been synthesized by the reaction of 3-amino-2-(4-thioxo-1,4-dihydrop yridin-3-yl-sulfonyl)guanidine with either 2-oxoalkanoic acids and its esters, or phenylglyoxylic hydrates in glacial acetic acid. Some of them exhibited reasonable or moderate anticancer activity toward human cancer cell lines, HCT-116, MCF-7 and HeLa. The structure of this novel heterocyclic ring system was confirmed by 2D-NMR and 2D-NMR spectroscopic data including COSY, ROESY and HMBC, elemental analyses and MS spectrometry.