Synthesis and biological evaluation of new 1,4‐benzothiazine derivatives as potential COX‐2 inhibitors

Abstract

A series of new 2H-benzo [1,4]thiazine derivatives were synthesized from aroylmethylidene malonates and o-aminothiophenols by condensation/ cyclization methodology in order to evaluate their COX-2 inhibitory activity. In-silico studies indicated that among the synthesized compounds, 5i could serve as a potential candidate for the task. So, compound 5i was taken as a model ligand for in vitro studies. The favorable outcome of the studies showed that compound 5i is indeed an excellent inhibitor of COX-2.

Evaluation of dual potentiality of 2,4,5-trisubstituted oxazole derivatives as aquaporin-4 inhibitors and anti-inflammatory agents in lung cells

“…24 They could be easily prepared by the oxidative condensation of commercially available aryl methyl ketones with diethyl malonate in the presence of iodine and cupric oxide in DMSO. 25 Aroylmethylidene malonates when treated with nitriles in the presence of tin( iv ) chloride undergo conjugate addition followed by ring closure to give oxazoles in 72–92% yields (Table 1). 24 b The synthesized compounds 3a–j were characterized by IR, NMR and HRMS techniques.…”

“…To a mixture of aroylmethylidene malonate 1 (ref. 25) (1 mmol) and nitriles 2 (1 mmol) in 1,2-dichloroethane (5 mL) was added SnCl 4 (1 mmol). The reaction mixture was stirred at room temperature for 6 h. After the reaction was complete, the reaction mixture was quenched with ice-water and extracted with dichloromethane.…”

SnCl4-mediated one-pot synthesis of 2,4,5-trisubstituted thiazoles from nitro-substituted donor–acceptor cyclopropanes and thioamides

“…Even though the reactions did not work for cyclopropanes having electron-withdrawing groups on the aryl ring, the expected products of the reactions could be obtained indirectly in two steps. Accordingly, the intermediate aroylmethylidene malonates 2g and 2h were synthesized from the corresponding arylmethyl ketones and diethyl malonate by Wu's oxidative condensation methodology 11 and the intermediates when heated under reflux with thioacetamide ( 7a ) afforded the expected thiazoles 8g and 8h in 53% and 59% yields, respectively (Scheme 3). Similarly, a better yield of thiazole 8j (58%) was obtained when the respective aroylmethylidene malonate 2j prepared by Wu's method was used in the transformation (Scheme 3).…”

Cesium Carbonate-Promoted Reaction of Nitro-Substituted Donor–Acceptor Cyclopropanes with Salicylaldehydes in Water: Access to Chromane Derivatives

“…Among the typical reactions of DACs such as annulation, ring-opening, and rearrangement reactions, nitro-substituted DACs prefer to undergo ring-opening reactions . The products of the reactions often serve as versatile building blocks for pharmaceutically important heterocyclic compounds …”