合成路线1

The racemic 4-methoxytryptophan amide (I) is resolved using immobilized Penicillin G acylase, to afford the desired L-aminoacid (III), while leaving unaltered the enantiomeric D-amide (II). After protection of aminoacid (III) as the N-benzyloxycarbonyl derivative (IV), coupling with glycine methyl ester (V) gives dipeptide (VI). Hydrogenolysis of the benzyloxycarbonyl protecting group of (VI) yields amine (VII), which is then coupled with N-Cbz-L-tryptophan (VIII) to produce the protected tripeptide (IX). Hydrogenolysis of (IX) in the presence of Pd/C provides the tripeptide building block (X).