Provided are efficient methods for direct coupling of a maytansinoid with a carboxylic acid to prepare a maytansinoid C-3 ester in high yield using a rare earth metal-based or trifluoromethanesulfonate-based Lewis acid catalyst and a base together with a coupling reagent. Also provided are compositions used in such methods.
提供了一种高效的方法,用稀土
金属基或
三氟甲磺酸盐基的
路易斯酸催化剂和碱以及偶联试剂直接偶联马坦西酮与
羧酸,以高收率制备马坦西酮C-3酯。还提供了在这种方法中使用的组合物。