Reaction Steps
Following the procedure as described in PREPARATION 14A, and making non-critical variations using 4-methyl-3,4-dihydro-2H-benzo[b][1,4]oxazin-6-ol (McMurtrey, K. D., et al., J. Org. Chem. (1970), 35(12):4252-3) to replace chroman-7-ol, and 1-[(2R)-tetrahydrofuran-2-ylmethyl]-1H-indole-2,3-dione to replace 1-(diphenylmethyl)indoline-2,3-dione, 3-hydroxy-3-(6-hydroxy-4-methyl-3,4-dihydro-2H-1,4-benzoxazin-7-yl)-1-[(2R)-tetrahydrofuran-2-ylmethyl]-1,3-dihydro-2H-indol-2-one was obtained (92%) as a pale brown solid: 1H NMR (300 MHz, CDCl3) δ9.21 (d, J=13.6 Hz, 1H), 7.46 (d, J=7.2 Hz, 1H), 7.36 (dd, J=7.8, 7.8 Hz, 1H), 7.17 (dd, J=7.5, 7.2 Hz, 1H), 7.09 (d, J=7.8 Hz, 1H), 6.40 (s, 1H), 6.18 (s, 1H), 4.25-4.06 (m, 3H), 3.87-3.63 (m, 4H), 3.27-3.17 (m, 2H), 2.87 (s, 3H), 2.02-1.74 (m, 3H), 1.71-1.57 (m, 2H); 13C NMR (75 MHz, CDCl3) δ179.8, 179.7, 151.54, 151.52, 143.1, 143.0, 138.0, 137.4, 130.12, 130.10, 129.32, 129.29, 126.1, 126.0, 123.8, 114.8, 114.6, 113.1, 113.0, 110.4, 110.3, 103.5, 79.11, 79.06, 76.9, 76.7, 68.32, 68.26, 64.6, 48.9, 44.6, 38.5, 29.3, 29.1, 25.7, 25.6; MS (ES+) m/z 418.9 (M+23).
