Hydrochloric Acid → HCID 178427577, compound

Participants

Reaction Conditions

Reaction Steps

In 300 ml of dimethylformamide is dissolved 37.8 g (81.7 millimoles) of Z-Arg(Tos)-OH, and 8.25 g of N-methylmorpholine is added to the solution. Then, the mixture is cooled to -5° C. and 10.8 g of isobutyl chloroformate is dropped to the mixture over a period of 5 minutes. The mixture is stirred for 15 minutes and mixed with a liquid mixture formed by adding 5.9 g of N-methylmorpholine to a solution of 39.5 g (58.4 millimoles) of HCl .H-Leu-Leu-Gln-Gly-Leu-Val-NH2 [prepared by reducing the Z-compound having a melting point of 261° to 265° C. and an optical rotation [α]D25 of 43.9° (C=2, acetic acid) with equivalent amounts of HCl and trifluoroethanol in the presence of 10% Pd-C] in 400 ml of dimethylformamide. The mixture is stirred at -5° C. for 2.5 hours and added to 3 l of water. The formed precipitate is recovered by filtration, washed with methanol and dissolved in acetic acid, and the solution is added to water. The formed precipitate is recovered by filtration, washed with water and dried to obtain 52.5 g of intended Z-Arg(Tos)-Leu-Leu-Gln-Gly-Leu-Val-NH2 (the yield being 83%).

Provenance & Evidence