Cesium carbonate → HCID 67393198, compound

Participants

Reaction Conditions

Reaction Steps

A scintillation vial was charged with 4-amino-2-ethylthiazolo[4,5-c]quinolin-7-ol (1.0 eq., 1.0 mmol) and anhydrous DMF (2 mL). The mixture was warmed until a solution was obtained. An additional amount of DMF (1 mL) was added. To this stirred orange solution was added cesium carbonate (3.0 eq., 3.0 mmol) and a solution of ethyl 5-(chloromethyl)-2-furancarboxylate (1.0 eq., 1.0 mmol) dissolved in DMF (2 mL). Additional DMF (1 mL) was used to rinse the vial. The vial was capped and heated to 60° C. overnight. The reaction was monitored by HPLC. The reaction was quenched by adding the reaction mixture drop-wise to water (60 mL) with stirring. A precipitate formed. Crude ethyl 5-{[(4-amino-2-ethylthiazolo[4,5-c]quinolin-7-yl)oxy]methyl}-2-furoate was isolated as a solid by vacuum filtration. The solid was then dissolved in methanol and adsorbed onto silica gel (6 g) for purification by HPFC (0-15% CMA in chloroform, 1440 mL). Pure fractions were combined and concentrated to provide a solid which analysis indicated was the methyl ester. This material was recrystallized from acetonitrile to provide methyl 5-{[(4-amino-2-ethylthiazolo[4,5-c]quinolin-7-yl)oxy]methyl}-2-furoate as a light yellow crystalline solid, mp 184-186° C. MS (APCI) m/z 384 (M+H)+. Anal. calcd for C19H17N3O4S.0.30CH3CN: C, 59.49; H, 4.56; N, 11.68. Found: C, 59.35; H, 4.22; N, 11.71.

Provenance & Evidence