Studies with aza-heterocyclic N-oxides: Synthesis of some new aromatic N-oxide derivatives

Abstract

KEYWORDSBenzofuroxan derivative (1a) reacts with the cyanoacetanilides (2a-d) to give the benzimidazole derivatives (3a-d). Benzofuroxan (1b) reacts with rhodanine derivatives (4a,b) in presence of sodium ethoxide to give the arylaminobenzoimidazole derivatives (6a,b); while the last reaction afforded the thiazolidinone derivatives (8a,b) and the obenzoquinone dioxime derivatives (9a,b) when it was repeated in the presence of sodium acetate. Moreover, a series of quinoxalinyl 1,4-di-N-oxide derivatives were prepared starting from quinoxalin-1,4-di-N-oxide derivatives (10a-c). Plausible mechanisms to account for the formation of the products are discussed.Heterocyclic N-oxides Benzofuroxan Rhodanine o-Quinone dioximes Thiocarbohydrazide Curtius rearrangement

Thiazolidine‐4‐ones from Thiocarbohydrazides

“…On refluxing the hydrazide 283 with phenylisothiocyanate 31a , the corresponding 1,4‐disubstituted thiourea 284 was obtained. Refluxing of 284 with chloroacetic acid 71 , thiazolidinone derivatives 285 were produced in good yield (Scheme ) .…”

New Synthetic Approaches for Cytotoxic Activity of Novel 1,8‐Naphthyridine Derivatives

“…(g) Total WBC count was found to increase with a reduction in the hemoglobin content and increase of red blood cells. (h) Compounds (3), (12), and 5-FU showed minimal ascites and slight increase in body weight unlike control group.…”

“…(b) Mice that received compounds (3), (12), and (5-FU) were more protected against ascites and increase in weight than control mice. (c) Mice that received compounds (3) and (12) showed slight toxic symptoms such as dizziness, dirty look, erection of tail, and slow movement; also, the liver of animals was pale and slightly enlarged. (d) Percentage increase of life span over control showed to be high in mice treated with total extracts, where (e) mice that received compounds (3) and (12) showed comparable results to 5-FU.…”

“…Recently, our interest in the synthesis of various substituted heterocyclic systems, which could be adapted for the preparation of small libraries, has been the subject of several publications from our laboratory [9][10][11][12]. It is reported that the 1,2,4-triazole nucleus is associated with diverse pharmacological activities [13].…”