From cell cultures of Taxus chinensis var. mairei, yunnanxane [2 alpha, 5 alpha, 10-beta triacetoxy-14 beta-(2'-methyl-3'-hydroxyl)-butyryloxy-4(20),11-taxadiene, [1], and four new homologous esters, 2 alpha, 5 alpha, 10 beta, 14 beta- tetra-acetoxy-4(20),11-taxadiene [2], 2 alpha, 5 alpha, 10 beta- triacetoxy-14 beta-propionyloxy-4(20),11-taxadiene [3], 2 alpha, 5 alpha, 10 beta- triacetoxy-14 beta-isobutyryloxy-4(20),11- taxadiene [4], and 2 alpha, 5 alpha, 10 beta- triacetoxy-14 beta-(2'-methyl)-butyryloxy-4(20),11- taxadiene [5] have been isolated. Their structures were determined by spectroscopic methods.