Synthesis of Three New Macrocyclic Tetraamide Ligands

A facile route is described for the synthesis of a series of macrocyclic tetraamides 1, 4, 9, 12 - tetraazacyclo - 2, 3, 6, 7, 10, 11, 14, 15-tetrabenzo-cetanan - 5, 8, 13, 16 - tetraone (TCTCT), 1, 4, 10, 13 - tetraazacyclo -2, 3, 6, 8, 11, 12, 15, 17-tetrabenzo-octadecan-5, 9, 14, 18-tetraone(TCTOT) and 1, 4, 10, 13-tetraaza-cyclo-2, 3, 11, 12-dibenzo-6, 8, 15, 17-dipyrdyl-octadecan-5, 9, 14, 18-tetraone (TCPOT) derived from 1, 2-diaminobenzene based on a stepwise approach using diacid dichloride (1, 2-diacid dichloride benzene, 1, 3- diacid dichloride benzene, 2, 6 - diacid dichloride pyridine) or mix dianhydrides for ring closure. This method is applicable for the preparation of a variety of receptors of various ring size, heteroatom substitution and pendant chains.