反应详情

A solution of 2-methyl-6-nitro-2-(4-piperazin-1-yl-phenoxymethyl)-2,3-dihydro-imidazo[2,1-b]oxazole (200 mg, 0.34 mmol) and 4-carboxymethyl-piperazine-1-carboxylic acid tert-butyl ester (136 mg, 0.55 mmol) in DMF is treated with TBTU (179.8 mg, 0.55 mmol), triethyl amine (0.23 ml, 1.65 mmol) and stirred for 2 h. The mixture is diluted with water and extracted with ethyl acetate. The organic layer is dried over sodium sulfate and concentrated. The residue is purified by preparative TLC (10% methanol in dichloromethane to give 4-(2-{4-[4-(2-methyl-6-nitro-2,3-dihydro-imidazo[2,1-b]oxazol-2-ylmethoxy)-phenyl]-piperazin-1-yl}-2-oxo-ethyl)-piperazine-1-carboxylic acid tert-butyl ester as yellow oil (152 mg, 78%). ESI MS m/z 585 (M+H); 1H NMR (400 MHz, CDCl3) δ 8.01 (s, 1H), 6.83 (d, J=8.4 Hz, 2H), 6.78 (d, J=8.4 Hz, 2H), 4.48 (d, J=Hz), 4.18 (d, J=Hz, 1H), 4.14-4.02 (m, 2H), 3.82-3.71 (m, 4H), 3.56-3.38 (m, 4H), 2.91 (s, 2H), 2.52-2.42 (m, 4H), 1.75-1.62 (m, 4H), 1.42 (s, 9H).

1. extractionextracted with ethyl acetate
2. dry with materialThe organic layer is dried over sodium sulfate
3. concentrationconcentrated
4. customThe residue is purified by preparative TLC (10% methanol in dichloromethane