Benzyl Bromide → 28-O-benzyldihydrobetulinic acid

To a solution of (1S,3aS,5aR,5bR,7aR,9S,11aR,11bR,13aR,13bR)-9-hydroxy-1-isopropyl-5a,5b,8,8,11a-pentamethylicosahydro-1H-cyclopenta[a]chrysene-3a-carboxylic acid (3 g, 6.54 mmol) and potassium carbonate (1.808 g, 13.08 mmol) in DMF (60 mL) was added (bromomethyl)benzene (0.816 mL, 6.87 mmol). The reaction mixture was heated up to 60° C. for 3 h. LCMS indicated the starting material was consumed. The reaction mixture was quenched with 60 ml water, a white precipitate was observed. The white solid was collected through filtration and washed with distilled water. The solid was dried in the air to provide the title compound as white solid (3.3 g, 92%). 1H NMR (500 MHz, CHLOROFORM-d) δ ppm 7.42-7.28 (m, 5H), 5.27-5.01 (m, 2H), 3.18 (dt, J=11.22, 5.53 Hz, 1H), 2.40-2.09 (m, 3H), 1.91-1.73 (m, 2H), 1.72-0.78 (m, 21H), 0.95 (s, 3H), 0.91 (s, 3H), 0.84 (d, J=7.02 Hz, 3H), 0.80 (s, 3H), 0.75 (s, 3H), 0.73 (s, 3H), 0.73 (d, J=6.71 Hz, 3H).

1. customwas consumed
2. customThe reaction mixture was quenched with 60 ml water
3. filtrationThe white solid was collected through filtration
4. washwashed with distilled water
5. customThe solid was dried in the air

ORD-Eintrag

ord-fb6810f2fe6a4f539755cfd288704952

Quelldatensatz

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08802661B2