反应详情

Sodium hydride (12 mg, 60%, 0.30 mmol) was added to a solution of 4-amino-8-(cyclopentyloxy)-7-methoxy-2H-chromen-2-one (40 mg, 0.15 mmol), 3,4,5-trichloropyridine (27 mg, 0.15 mmol), and anhydrous DMSO (3 mL) at rt under N2. After 4 h, the reaction was poured into 1M KH2PO4 (40 mL) and extracted with ethyl acetate (40 mL×2). The combined extracts were dried, filtered, concentrated, and purified by silica gel chromatography (13:7→9:11; hexanes:ethyl acetate) to give 8-(cyclopentyloxy)-4-(3,5-dichloropyridin-4-ylamino)-7-methoxy-2H-chromen-2-one: 1H NMR (400 MHz, DMSO-d6): δ 9.50 (s, 1H), 8.81 (s, 2H), 7.93 (d, 1H), 7.20 (d, 1H), 4.83 (m, 1H), 4.63 (s, 1H), 3.91 (s, 3H), 1.80-1.00 (m, 8H); MS (ESI): 421.1.

1. extractionextracted with ethyl acetate (40 mL×2)
2. customThe combined extracts were dried
3. filtrationfiltered
4. concentrationconcentrated
5. custompurified by silica gel chromatography (13:7→9:11; hexanes:ethyl acetate)