Dichloromethane → N-[(1,1-dimethylethoxy)carbonyl]-2,6-dimethyl-tyrosyl-N-(3-phenylpropyl)-D-alaninamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A CH2Cl2 solution (100 ml) of the title compound from Example 9, (16.6 g, 43.6 mmole) was charged with 4.4 g (43.6 mmoles) of NMM and cooled to -45° C. To this solution was added 5.7 g (43.6 mmole) of IBCF and the mixture warmed to 10° C. The solution was then cooled to -25° C. before adding 7.4 g (54.5 mmole) of 3-phenylpropylamine. After allowing the reaction to warm to room temperature and stand overnight, it was diluted with 300 ml of EtOAc and extracted with three 100 ml portions of 0.5N KHSO4. The combined aqueous washes were extracted with 100 ml of EtOAc and this extract was combined with the original organic phase. The combined organic was then washed with one 150 ml portion of brine before drying it over Na2SO4. All solvent was removed under reduced pressure to give the title product as a foam. This material was chromatographed to give 10 g (46%) of a compound identical to diastereomer S of Example 3.

Herkunft & Nachweise