The Reactivity of <i>Gem</i> Cyanoester Ketene Dithiolates towards the Development of Potent Antioxidant Heterocycles

Abstract

The reactivity of gem cyanoester ketene dithiolates towards the development of a variety of heterocycles was studied and tested for antioxidant property. The compounds bis benzoxazolylmethylthiomethylene pyrazoles and isoxazoles displayed excellent radical scavenging activity when compared with the standard ascorbic acid.

Synthesis and Antioxidant Activities of Acetamidomethylsulfonyl Bis Heterocycles‐Oxazolyl/Thiazolyl/Imidazolyl‐1,3,4‐Oxadiazoles

“…The 1 H NMR spectra of 10a, 11a, and 12a displayed two singlet signals at d 4.32, 4.29, 4.30 and 4.37, 4.34, 4.36 ppm due to methylene protons flanked between carbonyl and sulfonyl and sulfonyl and acid functionalities, respectively. Esterification of compounds 10-12 with methanol in the presence of sulfuric acid gave methyl 2-((4-aryloxazol-2-ylcarbamoyl)methylsulfonyl)acetate (13), methyl 2-((4-arylthiazol-2-ylcarbamoyl)methylsulfonyl)acetate (14), and methyl 2-((4-aryl-1Himidazol-2-ylcarbamoyl)methylsulfonyl)acetate (15). Compound 12a displayed another broad singlet at d 12.61 ppm due to the NH of the imidazole ring.…”

“…The thiazole ring is a main structural motif of many natural compounds such as vitamin B 1 (thiamine), penicillin, and carboxylase. Motivated by the aforesaid findings and in continuation of our studies towards the synthesis and bioassay of different bis heterocyclic derivatives [12][13][14][15][16], the present work is formulated. The imidazole nucleus forms the main structure of some well-known components of the human organism, viz.…”

Structure activity relationship (SAR) study of benzimidazole scaffold for different biological activities: A mini-review

“…Compounds having pyrazolyl and isoxazolyl units in combination with bis benzoxazole ring showed excellent radical scavenging activity when compared with the standard ascorbic acid. Conversely, benzimidazole derivatives possessed least activity.SAR study is annotated in Fig.46 [86].…”

New regio-selective method of combinatorial synthesis of substituted thiophenes, thieno[3,2-b]pyridines and other heterocycles via combination of ‘domino’-type reactions

“…[14][15][16][17][18][19] However, the same reaction was also used to form 3-cyano-4-hydroxy thiophenes 20,21 or a mixture of the both isomers. 22 The reaction with 4-bromoacetoacetic ester yields a structure similar to the intermediate 6.…”