Triethylamine → n-{4-Fluoro-2-(methylcarbamoyl)benzyl}-3-benzyloxy-9-methyl-4-oxo-4,6,7,9-tetrahydropyrimido[2,1-c][1,4]oxazine-2-carboxamide

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Reaction Steps

A mixture of intermediate 27, 3-benzyloxy-9-methyl-4-oxo-4,6,7,9-tetrahydropyrimido[2,1-c][1,4]oxazine-2-carboxylic acid (0.172 g, 0.54 mmol) and intermediate 39, 2-(aminomethyl)-5-fluoro-N-methylbenzamide trifluoroacetate salt (0.177 g, 0.60 mmol) in dichloromethane (10 ml) was treated at 22° C. with triethylamine (0.17 ml, 1.22 mmol) followed by benzotriazole-1-yloxy-tris-pyrrolidino-phosphonium hexafluorophosphate (PyBOP) (0.340 g, 0.65 mmol). After 3 h, the reaction mixture was diluted with ethyl acetate, washed with saturated sodium bicarbonate and brine then dried over anhydrous magnesium sulfate. Evaporation of the solvent followed by chromatography of the residue on silica gel (elution gradient ethyl acetate 50-100% in toluene) gave 0.260 g (100% yield) of the title amide as a white solid. 1HNMR 400 MHz (CDCl3) δ (ppm): 1.70 (3H, d, J=6.6 Hz, CH3), 3.01 (3H, d, J=4.7 Hz, NCH3), 3.89 (2H, m, CH2), 4.14 (1H, m, CH), 4.29 (1H, m, CH), 4.53 (2H, d, J=6.7 Hz, NCH2), 4.69 (1H, q, J=6.6 Hz, OCH), 5.35 (2H, s, OCH2), 6.69 (1H, broad q, NH), 7.09 (1H, m, aromatic), 7.16 (1H, m, aromatic), 7.32 (3H, m, aromatics), 7.42 (1H, m, aromatic), 7.47 (2H, m, aromatics), 8.61 (1H, broad t, NH). HRMS (ESI+) calculated for C25H26FN4O5 [M+H+]: 481.1887: found: 481.1884.

Provenance & Evidence