A molecular entity comprising a cyclic or polycyclic assembly of binding sites that contains three or more binding sites held together by covalent bonds, and which defines a molecular cavity in such a way as to bind (and thus 'hide' in the cavity) another molecular entity, Makroheterotsüklilised ühendid, mille molekulis kaks või rohkem tsüklit on ühendatud heteroaatomeid sisaldavate etüleensildade abil.