Novos derivados do sistema heterocíclico 1H-pirazolo[3,4-b]piridina: síntese e assinalamentos de hidrogênios e carbonos por RMN 1D e 2D

• Autor(a) principal: Mello,Heloisa de
• Data de Publicação: 1999
• Outros Autores: Silva,Edson Fernandes da, Echevarria,Aurea, Carvalho,Mário Geraldo de, Bernardino,Alice Maria Rolim
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Química Nova (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40421999000100006
• topic: 1H-pyrazolo[3,4-b]pyridine; 1D and 2D NMR; heterocyclic compounds

The synthesis and NMR analysis of seven new 4-(aryl)amino-5-carboethoxy-1,3-dimethyl-1H-pyrazolo[3,4- b]pyridines (7-13) are described. The synthetic approach used involved the preparation of intermediates 5-aminopyrazol (4), the enamine derivative (5) and the 4-chloro-1H-pyrazolo[3,4-b]pyridine (6). Compounds (7-13) were obtained by treatment of 6 with the desired aniline. The structures of new heterocyclic compounds and their precursors intermediates were assigned on the basis of spectral analysis including 1D and 2D NMR experiments [¹H; 13C{¹H} and DEPT; ¹H x ¹H - COSY; ¹H x13C - COSY, nJ CH, n = 1, 2 or 3 (HETECOR and COLOC)].