tert-butyl (2S,4S,5R)-3-(2-aminoacetyl)-5-methoxycarbonyl-4-phenyl-2-thiazolidinecarboxylate 、
异氰酸间甲苯酯 在
crude product 、 silica 、 cyclohexane, ethyl acetate 、 expected product 、
甲醇 、 1H 作用下,
以
四氢呋喃 为溶剂,
反应 12.0h,
以0.13 g of tert-butyl (2S,4S,5R)-5-methoxycarbonyl-3-{2-[3-(3-methylphenyl)ureido]acetyl}-4-phenyl-2-thiazolidinecarboxylate is thus obtained in the form of a white foam, [α]D25 =-9.5°±0.8° (c=1.0; CH3OH), 1H NMR: (200 MHz, (CD3)2SO with addition of a few drops of CD3COOD, at a temperature of 373 K, δ in ppm): 1.51 (s, 9H: CH3 of the tert-butyl); 2.28 (s, 3H: ArCH3); 3.69 and 4.05 (broad d and d respectively, J=17 Hz, 1H each: COCH2N); 3.78 (s, 3H: COOCH3); 4.31 (d, J=3.5 Hz, 1H: at C5 of the ring); 5.75 (s, 1H: H at C2 of the ring); 5.86 (d, J=3.5 Hz, 1H: H at C4 of the ring); 6.76 (broad d, J=7.5 Hz, 1H的产率得到tert-butyl (2S,4S,5R)-5-methoxycarbonyl-3-{2-[3-(3-methylphenyl)ureido]acetyl}-4-phenyl-2-thiazolidinecarboxylate