Calix[3]indoles, new macrocyclic tris(indolylmethylene) compounds with 2,7-linkages

A series of macrocyclic tris(indolylmethylene) compounds (calix[3]indoles] can be obtained from 7- or 2-hydroxymethylindoles or from the combination of either an indole with a bis(hydroxymethyl)-2,7′-diindolylmethane or a bis(hydroxymethyl)indole with a 2,7′-diindolylmethane; an isomeric series can be obtained from the combination of an indole with a bis(hydroxymethyl)-2,2′-diindolylmethane.