ABSTRACT
A highly efficient and simple method for the synthesis of 2-alkylbenzothiazoles through the condensation of 2-aminothiophenol and aliphatic aldehydes in the presence of active carbon/silica gel is described. The reaction proceeded under solvent-free and microwave irradiation to afford 2-alkylbenzothiazoles in high yields. This method was extended to the synthesis of bile acid derivatives containing a benzothiazole ring and obtained the desired products in high yields. The anti-inflammatory activity and cytotoxicity of the newly synthesized benzothiazole derivatives of bile acid were tested; the results showed that anti-inflammatory activities of all tested compounds tested were higher than that of standard drugs, such as indomethacin.
Subject(s)
Aldehydes/chemistry , Aniline Compounds/chemistry , Bile Acids and Salts/chemical synthesis , Charcoal/chemistry , Fatty Acids/chemistry , Microwaves , Silica Gel/chemistry , Thiadiazoles/chemical synthesis , Animals , Anti-Inflammatory Agents , Bile Acids and Salts/chemistry , Bile Acids and Salts/pharmacology , Female , Mice, Inbred ICR , Organic Chemistry Phenomena , Solvents , Thiadiazoles/chemistry , Thiadiazoles/pharmacologyABSTRACT
Mild and regioselective conversion of 3-keto-5α- and 3-keto-5ß-steroids (trans A/B- and cis A/B-ring juncture, respectively) to the corresponding enones (Δ(1)- and Δ(4)-3-ketones) by treatment with o-iodoxybenzoic acid (IBX) catalyzed by trifluoroacetic acid (TFA) in DMSO, is described. The IBX-mediated reaction involved dehydrogenation of the α- and ß-hydrogen atoms of the 3-ketones to give the enones regioselectively in good isolated yields without concomitant formation of related dienones and trienones.
