Since the the early 90 s a variety of unusual macrocyclic peptide alkaloids have been isolated from marine sources. The Lissoclinum cyclopeptides incorporate three or four amino acids contg. five membered heterocyclic rings in their backbones, which result from intramol. condensation of serine, threonine or cysteine side chains. The conformationally constrained structure of these cyclic peptides suggested us to utilize them as platforms for artificial receptors. In our research work we turned our attention to the functionalization of similar cyclohexapeptides in the position 5 of the three oxazole rings. Our attempt led to a versatile scaffold suited for further transformation to variable C3-sym. artificial receptors, conical or cylindrical shaped macrocyclic cavitands. Advantages of this platform are the greater distance between receptor arm bridgeheads and the property that it is recyclable in case of benzyl-type side chains.