Synthesis of 5-amino-4-(cyanoformimidoyl)-1H-imidazole: a reactive intermediate for the synthesis of 6-carbamoyl-1,2-dihydropurines and 6-carbamoylpurines
作者:M. José Alves、Brian L Booth、M. Fernanda J. R. P. Proenç
DOI:10.1039/p19900001705
日期:——
5-Amino-4-(cyanoformimidoyl)-1H-imidazole (3) has been prepared in good yield by the base-catalysed cyclisation of (Z)-N-(2-amino-1,2-dicyanovinyl)formamidine. Compound (3) reacts with ketones, R1COR2[R1= R2= Et, Me, Bu, –(CH2)5–, PhCH2; R1= Me, R2= Ph] togive2,2-disubstituted-6-carbamoyl-1,2-dihydropurines as the major products, together with minor amounts of compounds believed to be novel 7-amino-1-carbamoyl-3
通过(Z)-N-(2-氨基-1,2-二氰基乙烯基)甲idine的碱催化环化,已经以良好的产率制备了5-氨基-4-(氰基甲酰亚胺基)-1H-咪唑(3)。化合物(3)与酮反应,R 1 COR 2 [R 1 = R 2 = Et,Me,Bu,–(CH 2)5 –,PhCH 2 ; R 1 = Me,R 2 = Ph]以2,2-二取代-6-氨基甲酰基-1,2-二氢嘌呤为主要产物,以及少量的被认为是新颖的7-氨基-1-氨基甲酰基-3的化合物, 3-二取代的3 H-咪唑并[1,5-c ]咪唑衍生物,当R 1= R 2= Et,Bu和PhCH 2时已分离;当R 1= R 2= Ph时,仅将分离出的产物暂定为咪唑并[1,5- c ]咪唑结构。在与乙酰丙酮的反应中,1,2-二氢嘌呤中间体不稳定,失去丙酮,生成2-甲基-6-氨基甲酰基嘌呤。醛RCHO [R = Me,Et,(E)-MeCH CH–,c -C 4