2-氨基噻唑5位的羟甲基化和胺甲基化

采用微波法、封管加热以及酯基还原三种方法,在2-氨基噻唑衍生物的5位引入羟甲基,得到一系列新的5位羟甲基取代的新衍生物.并将三种方法进行对比,结果表明,封管加热对底物热稳定性要求苛刻,反应时间长,反应液杂,反应收率低.酯基还原的方法需在合成噻唑前引入酯基后还原,路线长,且收率低.采用微波法,反应时间短,转化率高,反应液副产物少,收率明显高于其他两种合成方法.同时报道了用NaH作碱制得氰基酯钠盐,再经关怀关环、还原得到一系列5位为氨甲基的噻唑新衍生物.

Hydroxymethylation and Aminomethylation of 2-Aminothiazol Derivatives at 5 Position

Hydroxymethylation of 2-aminothiazol derivatives at 5 position irritated by microwave was reported.The reaction results were compared by the method of microwave,sealed tube and reduction from ester.A series of novel hydroxymethyl derivatives were obtained.Through the experiments,sealed tube condition demanded high thermal stability of the substrate,and the reaction yield was low with messy reaction solution and long reaction time.The yield of reduction from ester is poor with longer synthetic route.The hydroxymethylation under microwave irradiation gave high yields with short reaction times.2-Cyanoacetate sodium salt was prepared from NaH,and the yield was improved.Novel derivatives of aminomethylation on 5 position are obtained after cyclization and reduction.