Citric Acid → HCID 56993776, compound

Participants

Reaction Steps

To a stirred mixture of commercially available S-4-monomethoxytrityl-(L)-cysteine (11) (0.34 g, 1 mmol), dioxane (5 mL) and 10% aqueous sodium carbonate (5 mL) was added 2-naphtalenesulfonyl chloride (0.25 g, 1.1 mmol). After stirring for 1 h, the reaction mixture was acidified by addition of 5% aqueous citric acid (50 mL) and extracted with ethyl acetate (2×50 mL). The combined organic layers were dried (magnesium sulfate) and concentrated under reduced pressure. The crude product was chromatographed on silica gel (methanol/dichloromethane/triethylamine, 0/99/1 to 4/95/1, v/v/v) to yield 12 (76% yield, 0.44 g).

Provenance & Evidence