Diisopropylethylamine → 5-Ethoxy-1,3-dihydro-1-[2-methoxy-4-(N-(1-ethoxycarbonyl-1-methylethyl)carbamoyl)benzenesulfonyl]-3-cyclohexyl-2H-benzimidazol-2-one

Participants

Reaction Steps

500 mg of the compound obtained in Example 13, 300 mg of 1-ethoxycarbonyl-1-methylethylamine hydrochloride and 550 mg of BOP were mixed with 2 ml of DIPEA and 50 ml of DCM and the reaction medium was stirred for 30 minutes at room temperature. It was then concentrated under vacuum and the residue was taken up with water and then extracted with AcOEt, washed successively with 1N HCl , with 1N NaOH and then with water, dried over sodium sulfate and concentrated under vacuum. The residue was purified by chromatography on a silica column using a DCM/AcOEt mixture (97/3; v/v) as the eluent. 170 mg of the expected product were obtained in the form of a white solid by crystallization from an AcOEt/iso ether mixture (10/90; v/v). M.p.=202° C.

Provenance & Evidence