[摘要]：An optimized protocol for the mild and selective Fukuyama-Mitsunobu reaction was used for mono- and di-N-alkylation on solid support. Thereby, nonfunctionalized aliph. and arom. residues are quickly introduced into transiently protected, primary amines of a linear peptide. N-Alkylation can also be used to implement alkyl chains carrying (protected) functionalities suited for subsequent modification. Applicability of this method is demonstrated by various N-alkylated analogs of a cyclic CXCR4 receptor antagonist originally developed by Fujii et al.
