反应详情

3-{1,4-Dioxo-4-(phenylmethoxy)-2(R)-{[1-(triphenylmethyl)-1 H-imidazol-4-yl]methyl}butyl}-4-(S)-(1-methylethyl)-2-oxazolidinone: By following the procedure of example 2, section (f), but replacing the product of section (e) of that example with 4(S)-(1-methylethyl)-3-{1-oxo-3-[1-(triphenylmethyl)-1 H-imidazol-4-yl]propyl}-2-oxazolidinone of section (b) of this example, and replacing tert-butyl 2-bromoacetate with benzyl 2-bromoacetate, 3-{1,4-dioxo-4-(phenylmethoxy)-2-{[1-(triphenylmethyl)-1H-imidazol-4-yl]methyl}butyl}-4-(S)-(1 -methylethyl)-2-oxazolidinone was obtained as a mixture of 2(R)- and 2(S)-epimers in a 8 to 1 ratio by weight. Separation of the epimers by flash chromatography (SiO2, eluent: hexane-EtOAc, 1:2) yielded the desired 2(R)-epimer (Rf=0.25, eluent: hexane-EtOAc,1:2). The 1H NMR(CDCl3) of the 2(R)-epimer showed 6 7.34-7.28 (m, 15H), 7.13-7.08 (m,6H), 6.59 (d, J=1.3 Hz,1H), 5.06 (s,2H), 4.55-4.45 (m, 1H), 4.38 (td, J=3.9 Hz,5.4 Hz,1H), 4.15-4.10 (m,2H), 2.97 (dd, J=10.3 Hz,16.9 Hz,1H), 2.88 (dd, J=6.3 Hz,14.3 Hz,1H), 2.73 (dd, J=7.0 Hz,14.3 Hz,1H), 2.59 (dd, J=4.4 Hz,16.9 Hz,1H), 2.32 (hept d, J=3.9 Hz,7.0 Hz,1H), 0.87 (d, J=7.1 Hz,3H), 0.85 (d, J=6.8 Hz,3H).