3-(3,5-Dimethoxyphenyl)-2-{4-[4-(2,4-dioxothiazolidin-5-ylidenemethyl)-phenoxy]-phenyl}-propionic acid methyl ester → 3-(3,5-Dimethoxyphenyl)-2-{4-[4-(2,4-dioxothiazolidin-5-ylmethyl)-phenoxy]-phenyl}-propionic acid methyl ester

Participants

Reaction Steps

17 (1.6 g, 3.08 mmol) was dissolved in dioxane (45 mL), transferred in a hydrogenation bottle and Pd on carbon (10%, 1.0 g) was added. Hydrogenation was done at 65 psi for 34 h. Following this period, additional Pd on carbon (10%, 0.6 g) was added and hydrogenation was allowed to continue for another 18 h. Catalyst was filtered through a bed of Celite® and solvent was evaporated. The residue was purified by column chromatography on reverse phase silica gel (C-18) using acetonitrile-water (1:1) mixture to elute 18 as white solid (0.60 g, 38%): mp 125-128° C.; 1H NMR (400 MHz, DMSO-d6) δ 12.04 (br s, 1H), 7.31 (d, J=8.4 Hz, 2H), 7.25 (d, J=8.4 Hz, 2H), 6.92 (d, J=8.6 Hz, 4H), 6.30 (d, J=2.0 Hz, 2H), 6.29 (t, J=2.0 Hz, 1H), 4.90 (dd, J=9.2 and 4.4 Hz, 1H), 3.98 (t, J=8.0 Hz, 1H), 3.67 (s, 6H), 3.56 (s, 3H), 3.37 (dd, J=13.6 and 4.0 Hz, 1H), 3.21 (dd, J=14.0 and 8.8 Hz, 1H); 3.11 (dd, J=14.0 and 9.2 Hz, 1H) and 2.90 (dd, J=13.6 and 7.6 Hz, 1H); MS (EI) m/z 522[M]+; Anal. (C28H27NO7S) C, H, N.

Provenance & Evidence