Dimethylformamide → RS-93522

Participants

Reaction Steps

Similarly, a solution of 4.5 g of 2,6-dimethyl-3-methoxycarbonyl-4-(3-nitrophenyl)-5-[2-(4-aminophenyl)ethoxycarbonyl]-1,4-dihydropyridine (11), 1.8 mL 2-bromoethanol, 2 mL triethylamine and 20 mL DMF was stirred at 80° C. for 3 h. The mixture was added to water and extracted with ethyl acetate. The ethyl acetate was washed with water, dried over Na2SO4, evaporated to a residue, and purified by silica gel chromatography with 75% ethyl acetate-hexane to afford 2,6-dimethyl-3-methoxycarbonyl-4-(3-nitrophenyl)-5-(2-[4-(2-hydroxyethylamino)phenyl]ethoxycarbonyl)-1,4-dihydropyridine (1) as a free base. This was dissolved in methanolic HCl and evaporated under reduced pressure to yield 2.6 g of 2,6-dimethyl-3-methoxycarbonyl-4-(3-nitrophenyl)-5-(2-[4-(2-hydroxyethylamino)phenyl]ethoxycarbonyl)-1,4-dihydropyridine hydrochloride as an amorphous solid, m.p. 102°-104° C.

Provenance & Evidence