Davis–Beirut Reaction: Route to Thiazolo-, Thiazino-, and Thiazepino-2H-indazoles
نویسندگان
چکیده
Methods for the construction of thiazolo-, thiazino-, and thiazepino-2H-indazoles from o-nitrobenzaldehydes or o-nitrobenzyl bromides and S-trityl-protected 1°-aminothioalkanes are reported. The process consists of formation of the requisite N-(2-nitrobenzyl)(tritylthio)alkylamine, subsequent deprotection of the trityl moiety with TFA, and immediate treatment with aq. KOH in methanol under Davis-Beirut reaction conditions to deliver the target thiazolo-, thiazino-, or thiazepino-2H-indazole in good overall yield. Subsequent S-oxidation gives the corresponding sulfone.
منابع مشابه
SYNTHESIS AND PHARMACOLOGICAL EVALUATION OF 6-CARBETHOXY-5-(3'-BROMOPHENYL)-3-ARYL-2-CYCLOHEXENONES AND 6-ARYL-4-(3'-BROMOPHENYL)-3-OXO-2,3A,4,5-TETRAHYDRO-2H-INDAZOLES
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