反应详情

温度

-20 °C

4.95 g of Z-Nle-OH dissolved in 50 ml tetrahydrofuran are cooled to -20° C. and 2.1 ml of N-methylmorpholine followed by 2.43 ml of chloroformic acid isobutylester are added to the solution with stirring. The solution is stirred for a further 10 minutes at -15° C. and a cold solution comprising 10.6 g of H-Asn-Phe-Phe-OMe. hydrobromide and 2.5 ml of N-methylmorpholine in 60 ml N,N-dimethylformamide/tetrahydrofuran (1:1) are added. The solution is stirred for 20 hours at 0° C. and for 2 hours at room temperature and subsequently stirred with aqueous ethanol. After filtration, washing with (a) methanol and (b) ether and drying, the title compound is obtained [α]D20 =-31° (c=1.0 in dimethylformamide): decomposition at 235° C.

1. additionare added to the solution
2. stirringThe solution is stirred for a further 10 minutes at -15° C.
3. stirringThe solution is stirred for 20 hours at 0° C. and for 2 hours at room temperature
4. filtrationAfter filtration
5. washwashing with (a) methanol and (b) ether
6. customdrying