Dimethyl Sulfate → HCID 91043669, compound

Participants

Reaction Steps

The product of Step 1 (6.20 g) is dissolved in ethyl acetate (100 mL). DBU (2.20 g) and dimethyl sulphate (1.83 g) are added sequentially. The reaction mixture is stirred at room temperature for 2 hours, then partitioned between ethyl acetate and water. The organic layer is washed with water and brine, dried over magnesium sulphate and evaporated. Crystallisation from methanol affords furan-2-carboxylic acid (6S,9S,10S,11S,13S,16R,17R)-9,11-epoxy-6-fluoro-17-methoxycarbonyl-10,13,16-trimethyl-3-oxo-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-17-yl ester. Selected 1H-NMR signals (CDCl3) δ 3.75 (3H, s), 6.30 (1H, dd), 6.45 (1H, d), 6.55 (2H, m), 7.15 (1H, d), 7.60 (1H, d).

Provenance & Evidence