反应详情

The protected amide, 3(R)-(cyclopropylmethyl)-4-{[1(S)-(cyclohexylmethyl)-2(R),3(S)-dihydroxy-5-methylhexyl]amino}-4-oxobutanoic acid tert-butyl ester: Following the procedure of section (g) of example 2, the product of section (b) of this example (10.2 g, 30 mmol) was reacted with lithium hydroxide-hydrogen peroxide to give the desired monoprotected dicarboxylic acid, i.e. the 4-tert-butyl ester of 2(R)-(cyclopropylmethyl)butanedioic acid, as a colorless oil (6.65 g, 97%); [α]D23 +16.1° (c 2.61, CHCl3).