反应详情

4-{[1(S)-(Cyclohexylmethyl)-2(R),3(S)-dihydroxy-5-methylhexyl]amino}-4-oxo-3-(R)-(4-thiazolylmethyl)butanoic acid tert-butyl ester: The latter 2-oxazolidinone derivative (4.02 g, 10.5 mmol) was reacted with lithium hydroxide-hydrogen peroxide according/to the procedure of example 2, section (g) to give the monoprotected dicarboxylic acid of formula 2, i.e. the 4-tert-butyl ester of 2(R)-(4-thiazolylmethyl)butanedioic acid. Subsequent coupling of the latter compound (2.83 g, 10.4 mmol) with 2(S)-amino-1-cyclohexyl-6-methyl-3(R), 4(S)-heptanediol hydrochloride (3.21 g, 11.5 mmol) according to the coupling procedure of example 2, section (g) gave the desired protected amido acid as a white solid (3.75 g, 72%); 1H NMR(CDCl3) δ 8.70 (s, 1H), 7.10 (s,1H), 5.96 (d, J=8.3 Hz,1H), 4.40-4.25 (m,2H), 3.40-2.70 (m,6H), 2.40 (dd, J=4.4 Hz,16.8 Hz,1H), 1.95-1.10 (m,17H), 1.40 (s,9H), 0.90 (d, J=6.6 Hz,3H), 0.80 (d, J=6.4 Hz,3H).