Dimethylformamide → Z-Asn-Leu-OMe
Reaction equation
[NH2:1][C@H:2]([C:7]([O:9][CH3:10])=[O:8])[CH2:3][CH:4]([CH3:6])[CH3:5].[CH:11]1[CH:16]=[CH:15][C:14]([CH2:17][O:18][C:19]([NH:21][C@H:22]([C:27](OC2C=CC([N+]([O-])=O)=CC=2)=[O:28])[CH2:23][C:24]([NH2:26])=[O:25])=[O:20])=[CH:13][CH:12]=1.CN(C)C=O>O>[NH:21]([C:19]([O:18][CH2:17][C:14]1[CH:15]=[CH:16][CH:11]=[CH:12][CH:13]=1)=[O:20])[C@H:22]([C:27]([NH:1][C@H:2]([C:7]([O:9][CH3:10])=[O:8])[CH2:3][CH:4]([CH3:6])[CH3:5])=[O:28])[CH2:23][C:24](=[O:25])[NH2:26]Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution of 16.7 g of H-Leu-OMe and 46.0 g of Z-Asn-ONP in 100 ml of freshly distilled dimethylformamide is kept for 19 hours at 25° C., then 1.2 litres of water are added and the crystalline precipitate is suctioned off. The dipeptide derivative is dried under vacuum at 40° C. and then twice recrystallized from aqueous methanol. It melts at 180°-181° C. Optical rotation [α]D20 =+9° (c=2.05 in chloroform).