Fuming nitric acid (9 ml) was added to a stirred suspension of 7-(3-[4-Acetyl-3-hydroxy-2-n-propylphenoxy]-2 -hydroxypropoxy)-4-hydroxycoumarin (2.8 g) in chloroform (300 ml) over 1 hr at 0° and the dark mixture stirred for a further 0.5 hr at this temperature. Dilute hydrochloric acid (150 ml) was added and the chloroform removed in vacuo at 0°. The solid which separated was removed by filtration and recrystallised from ethanol to give 2.42 g, (78%) of yellow solid of mp 201°-203° (dec). υmax (mull) 3350 (br), 1770, 1620, 1610, 1540 cm-1 ; τ(DMSO); 9.17 (3H, t, J 6.9 Hz); 8.55 (2H, m, J ca 7 Hz); 7.43 (3H, S+2H, m); 5.78 (5H, S); 3.20 (3H, m); 2.16 (2H, exchangeable S); 2.16 (2H, near doublet); 1 low field broad exchangeable). (Found, C, 58.49; H, 5.07; N, 3.04; C23H23NO10 requires, C, 58.35; H, 4.90; N, 2.96%).
