Nucleophilic Carbenes and Pseudo??Cross??Conjugated Mesomeric Betaines of Indazole Starting from Analogues of the Alkaloid??Betaine Nigellicine

A Schmidt, L Merkel, W Eisfeld

Index: Schmidt, Andreas; Merkel, Lars; Eisfeld, Wolfgang European Journal of Organic Chemistry, 2005 , # 10 p. 2124 - 2130

Full Text: HTML

Citation Number: 24

Abstract

Abstract The alkaloid Nigellicine possesses the indazolium-3-carboxylate ring system as electronically relevant partial structure which represents a member of the class of pseudo- cross-conjugated mesomeric betaines. Indazolium-3-carboxylate, prepared starting from indazole-3-carboxylic acid by an esterification–methylation–saponification sequence, can be converted into the isoconjugated phenyl-and 4-(nitrophenyl) amidates and the ...