Pyridine → 6-Amidino-1-carbamoylmethyl-2-naphthyl 4-dimethylaminobenzoate.dihydrochloride

Participants

Reaction Steps

40 Milliliters of 20% hydrous pyridine was added to 3.0 g of 4-dimethylaminobenzoic acid, 1.77 g of 6-amidino-1-carbamoylmethyl-2-naphthol.hydrochloride, 2.65 g of DCC and 130.9 mg of DMAP, followed by stirring for 2 hours under cooling with ice and then 24 hours at room temperature. Then, the precipitate was collected by filtration and washed with a small amount of pyridine. To this collected precipitate were added 60 ml of DMF and 20 ml of water to dissolve the precipitate with heating, followed by stirring for 2 hours under cooling with ice. Then, insoluble matter was filtered off and the filtrate was concentrated under reduced pressure. To the residue were added 15 ml of DMF and 10 ml of water to dissolve the residue. The solution was added dropwise to 400 ml of acetone, followed by stirring for 24 hour under cooling with ice. The precipitate was collected by filtration to obtain a crude product. Then, the product was subjected to silica gel column chromatography using methyl ethyl ketone-water-acetic acid (80:15:5) as an eluent, and the desired fractions were collected and the solvent was distilled off under reduced pressure. The residue was suspended in 15 ml of methanol, 5 ml of DMF and 0.9 ml of concentrated hydrochloric acid, and the suspension was added dropwise to a mixed liquid of 200 ml of acetone and 100 ml of ether, followed by stirring for 24 hours under cooling with ice. Then, the precipitate was collected by filtration to obtain 1.96 g of the desired product.

Provenance & Evidence