反应详情

In analogy to the procedure described in example 1 d], [rac]-2-ethoxy-3-(2-ethoxy-4-hydroxy-phenyl)-propionic acid ethyl ester (example 58 c]) was reacted with 2-[5-methyl-2-(4-trifluoromethyl-phenyl)-thiazol-4-yl]-ethanol [PCT Int. Appl. (2001), WO 01/00603 A1] in tetrahydrofuran in the presence of triphenylphosphine and DBAD (di-tert-butyl azodicarboxylate) to yield [rac]-2-ethoxy-3-(2-ethoxy-4-{2-[5-methyl-2-(4-trifluoromethyl-phenyl)-thiazol-4-yl]-ethoxy}-phenyl)-propionic acid ethyl ester, which was further saponified in analogy to the procedure described in example 1 e], to yield [rac]-2-ethoxy-3-(2-ethoxy-4-{2-[5-methyl-2-(4-trifluoromethyl-phenyl)-thiazol-4-yl]-ethoxy}-phenyl)-propionic acid as colorless oil.

1. customdescribed in example 1 d