Studies on 3-aminoindazoles. I. Synthesis of 1- or 3-(substituted 3-amino)indazoles.
作者:HIROMU KAWAKUBO、KENTARO FUKUZAKI、TAKANORI SONE
DOI:10.1248/cpb.35.2292
日期:——
Various 1-or 3- (substituted 3-amino) indazoles with anti-inflammatory effects were synthesized by means of three methods, as follows. 1) Reactions of 3-aminoindazole (1) with acrylamides (2a and 2b) gave amide derivatives (3a and 3b) having a carbamoylethylamino group at the 3-position of 3a and 3b. The amide derivatives (3a and 3b) were converted to thioamide derivatives (4a and 4b) by treatment with P2S5. Electrode reduction of 4a and 4b gave 3- (substituted 3-amino) indazoles (5a and 5b). 2) The reaction of 1 with aminoalkyl. halides (6c-r) gave 3- (substituted 3-amino) indazoles (5c-r) and 1- (substituted 3-amino) indazoles (7c-r) in a ratio of 3 : 1. 3) The reaction of 1 with phthalic anhydride (8) gave 3-phthalimidoindazole (9). Compound 9 was allowed to react with aminoalkyl halides (6o-r) to give 1-substituted derivatives (10s-z) of 9, Reactions of 10a-z with hydrazine hydrate gave 1- (substituted 3-amino) indazole derivatives (5s-z).
通过以下三种方法合成了各种具有消炎作用的 1-或 3-(取代的 3-氨基)吲唑。1) 3-氨基吲唑(1)与丙烯酰胺(2a 和 2b)反应,得到酰胺衍生物(3a 和 3b),3a 和 3b 的 3 位上有氨基甲酰乙氨基。酰胺衍生物(3a 和 3b)经 P2S5 处理后转化为硫代酰胺衍生物(4a 和 4b)。电极还原 4a 和 4b,得到 3-(取代的 3-氨基)吲唑(5a 和 5b)。2) 1 与氨基烷基卤化物(6c-r)反应,得到 3-(取代的 3-氨基)吲唑(5c-r)和 1-(取代的 3-氨基)吲唑(7c-r),比例为 3 : 1。化合物 9 与氨基烷基卤化物 (6o-r) 反应,得到 9 的 1-取代衍生物 (10s-z),10a-z 与水合肼反应,得到 1-(取代的 3-氨基)吲唑衍生物 (5s-z)。