反应详情

In analogy to the procedure described in example 108 c], [rac]-2-ethoxy-3-(7-hydroxy-benzo[b]thiophen-4-yl)-propionic acid methyl ester (example 151 a]) was treated with 4-chloromethyl-2-(4-tert-butyl-phenyl)-5-methyl-oxazole (prepared from 4-tert-butyl-benzaldehyde and diacetyl monoxyme followed by treatment with POCl3 in analogy to the procedures described in examples 21 a] and b]) and sodium hydride in N,N-dimethylformamide to yield [rac]-3-{7-[2-(4-tert-butyl-phenyl)-5-methyl-oxazol-4-ylmethoxy]-benzo[b]thiophen-4-yl}-2-ethoxy-propionic acid methyl ester, which was further saponified in analogy to the procedure described in example 91 e] to yield [rac]-3-{7-[2-(4-tert-butyl-phenyl)-5-methyl-oxazol-4-ylmethoxy]-benzo[b]thiophen-4-yl}-2-ethoxy-propionic acid as colorless amorphous solid.