A one-pot four component (ABC2) synthesis of macrocycles, e.g. I, is reported. This novel one-pot multicomponent synthesis delivers at least three elements of diversity into the final macrocycles. The overall process leads to the creation of six chem. bonds with the concomitant formation of two oxazole groups as part of a new macrocycle, and thus involves a large increase in mol. complexity. The synthesis is ecol. benign and atom economic since only two mols. of water are lost in this rather complex bond-forming process. [on SciFinder (R)]