Synthesis and characterization of new porphyrin/β-cyclodextrin derivatives covalently connected by aliphatic chains of different length

Abstract

Covalently linked porphyrin/β-cyclodextrin derivatives have been synthesized by reaction between 5,10,15-tris-{p-[9-methoxy-tris-(ethyleneoxy)-phenyl]}-20-(p-hydroxyphenyl)-porphyrin, β-cyclodextrin-6-alcoholate and di-brominated aliphatic chains of different length, and characterized by MALDI-TOF mass spectrometry, 1H NMR and UV-vis spectroscopy. As a function of chain length, these compounds exhibit different degrees of water solubility, becoming higher with increasing chain length. The lack of self-assemblies between porphyrins and β-cyclodextrins (which renders the two sub-units completely free to perform their activities) and their water solubility, make these compounds excellent candidates in fields like drug-delivery or photodynamic therapy.