1-Hydroxybenzotriazole → 4-[2-(2-{5-[5-(2,6-dichloro-phenylmethanesulfonyl)-2-oxo-1,2-dihydro-indol-(3 Z)-ylidenemethyl]-2,4-dimethyl-1H-pyrrol-3-yl}-acetylamino)-ethyl]-piperazine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of {5-[5-(2,6-dichloro-phenylmethanesulfonyl)-2-oxo-1,2-dihydro-indol-(3Z)-ylidenemethyl]-2,4-dimethyl-1H-pyrrol-3-yl}-acetic acid (519 mg, 1 mmol) in DMF (5 mL) was added HOBt (202 mg, 1.3 eq.), EDAC.HCl (288 mg, 1.5 eq.) and TEA (302 mg, 3 eq.). After stirring at rt for 30 mins, to the mixture was added 4-(2-amino-ethyl)-piperazine-1-carboxylic acid tert-butyl ester (298 mg, 1.3 eq.). After stirring at 40° C. for 24 hours, the reaction was concentrated and the residue was purified on a silica gel column to give 4-[2-(2-{5-[5-(2,6-dichloro-phenylmethanesulfonyl)-2-oxo-1,2-dihydro-indol-(3Z)-ylidenemethyl]-2,4-dimethyl-1H-pyrrol-3-yl}-acetylamino)-ethyl]-piperazine-1-carboxylic acid tert-butyl ester as a yellow solid.

Provenance & Evidence