Trimethyl orthoformate → 6-{[(1H-imidazol-2-ylmethyl)-amino]-methyl}-5,6,7,8-tetrahydro-imidazo[1,2-a]pyridine-2-carboxylic acid-(4-dipropylamino-butyl)-amide

Participants

Reaction Steps

The compound (28.3 mg) obtained in Example 19-3 was dissolved in methanol (1.0 ml) and added with trimethyl orthoformate (0.030 ml) and 2-imidazole carboxaldehyde (11.7 mg), and the whole was stirred at room temperature for 3 hours. After having been cooled to 0° C., the solution was added with sodium borohydride (4.6 mg) and the whole was warmed to room temperature and stirred for additional 15 minutes. The resultant was added with water to stop the reaction and subjected to extraction with chloroform. The organic layer was washed with water and a saturated saline solution and dried with anhydrous sodium sulfate. The solvent was distilled off. The residue was purified through silica gel column chromatography (chloroform/ethyl acetate), thereby obtaining the subject compound (30.5 mg) as a colorless oily substance.

Provenance & Evidence