An efficient and convergent route towards water-soluble, chiral and amphiphilic macrocycles

A practical procedure for the synthesis of water-soluble, chiral and amphiphilic macrocyclic molecules is described. Acylation of p-xylylene diamine with Fmoc-protected glycine and aspartic acid, followed by removal of the Fmoc moiety afforded amino acid:p-xylene conjugates as free diamines. These diamines were converted to symmetrical and unsymmetrical macrocycles via stepwise urea formation using p-nitrophenyl chloroformate.