The Trp-phenylglycinol} pseudodipeptide (alpha R,3R*,4R*)-N-(2-acetoxy-1-phenylethyl)-3-amino-4-indolyl-2-piperidone 33 has been synthezised by condensation of the 3-amino-substituted anhydride 30 with (R)-(-)-phenylglycinol followed by reduction of the resulting imide.