反应详情

Analogously to the procedure described in Example 1, starting from ethyl 3-amino-4,4,4-trifluorocrotonate and 3,4-dihydro-7-fluoro-6-isocyanato-3-oxo-4-(2-propynyl)-2H-1,4-benzoxazine there is obtained 6-{3-[2-(ethoxycarbonyl)-1-trifluoromethyl-vinyl]ureido}-3,4-dihydro-7-fluoro-3-oxo-4-(2-propynyl)-2H-1,4-benzoxazine (not isolated) and, after cyclization of this benzoxazine, there is obtained 3-[3,4-dihydro-7-fluoro-3-oxo-4-(2-propynyl)-2H-1,4-benzoxazin-6-yl]-6-trifluoromethyl-2,4(1H,3H)-pyrimidinedione, 1H-NMR (CDCl3, 60 MHz): 7.29 ppm (d, 1H), 6.99 ppm (d, 1H), 6.31 ppm (s, 1H), 4.85-4.61 ppm (m, 4H), 2.35 ppm (t, 1H): mass spectrum: m/e 383(20), M+.