| 摘要 |
Prepn. of phenylbutyricacid derivs. of formula (I) comprises resolution of (R,S)-2-hydroxy-4-phenylbutyric acid with D(-)threonureor L(+) threonine, 1,paranitrophenyl-2-amino-1,3-propanediol, isolating the (R) or (3) -2-hydroxy-4-phenylbutyric acid, esterifying and reacting their 2-trimethylsilyloxy derivs. with triflic anhydride. The conversion of the (S) and (R) hydroxyacids is by reaction of the briflates with Et3NOAc, with regioselective inversion on hydrolysis of acetate with retention of configuration.
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