反应详情

Analogously to Example 1j), 1.4 g (2.69 mmol) of 5(S)-(Boc-amino)-4(S)-hydroxy-6-phenyl-2(R)-(p-benzyloxyphenylmethyl)-hexanoic acid in 2.9 ml of DMF are silylated with 1.87 g (12.4 mmol) of tert-butyldimethylchlorosilane and 1.5 g (22 mmol) of imidazole. Hydrolysis of the silyl ester function with 2.2 g of potassium carbonate in 63 ml of methanol/THF/water 3:1:1 and column chromatography (SiO2, hexane/ethyl acetate 2:1) of the crude product yields the title compound: TLC Rf (D)=0.17; tRet (II)=33.7 min; FAB-MS (M+H)+ =634.