1-Hydroxybenzotriazole → HCID 54359784, compound

Participants

Reaction Steps

To a stirred solution of 3-[2-(tert-butoxycarbonyl-pyridin-4-yl-amino)-ethoxy]-5-chloro-benzoic acid (0.300 g), TBTU (0.482 g) and HOBt (0.150 g) in DMF (5 ml) was added DIPEA (0.260 ml) followed by 4-cyclopentylamino-butyric acid ethyl ester (0.316 g) after 10 min. The reaction mixture was stirred at room temperature for 16 h and then further 4-cyclopentylamino-butyric acid ethyl ester (0.316 g) was added. After 24 h, the reaction mixture was concentrated under reduced pressure to give a viscous gum which was partitioned between ethyl acetate and water. The aqueous layer was removed and the organic phase washed with further water, aqueous saturated sodium bicarbonate solution, water and dried with brine and over sodium sulphate. The organic phase was concentrated under reduced pressure to give crude product as a black gum (0.420 g) which was purified by preparative hplc and the title compound (0.189 g) was obtained as a colourless gum by concentration of the required fraction under reduced pressure and drying by repetitive addition of acetonitrile and concentration under reduced pressure.

Provenance & Evidence