Propylamine → Methyl 5-({1-[3-(methoxycarbonyl)phenyl]-2-methylindolizin-3-yl}carbonyl)-2-[(propylcarbamoyl)amino]benzoate

Participants

Reaction Steps

0.143 mg (0.47 mmol) of triphosgene diluted in 2 ml of dioxane are added, under an inert atmosphere at ambient temperature, to 308 mg (0.68 mmol) of methyl 2-amino-5-({1-[3-(methoxycarbonyl)phenyl]-2-methylindolizin-3-yl}carbonyl)benzoate in 5.6 ml of dioxane. The reaction medium is stirred for 2 hours at ambient temperature and then 0.28 ml (2.03 mmol) of triethylamine, and 0.11 ml (1.35 mmol) of n-propylamine diluted in 4 ml of dioxane are added. After stirring for 2 hours, the reaction medium is hydrolysed with water. The aqueous phase is extracted with dichloromethane. The organic phase obtained is washed with a 1N aqueous solution of hydrochloric acid, and then with a saturated aqueous solution of sodium chloride, dried over sodium sulphate, filtered, and concentrated under reduced pressure. The solid obtained is purified by silica gel column chromatography, elution being carried out with a dichloromethane/methanol (95/5) mixture.

Provenance & Evidence