Calixarenes in Bioorganic Chemistry

The selective introduction of two and four L-alanine and L-alanyl-L-alanine groups into calix[4]arenes, blocked in the cone conformation. We have synthesised C-linked peptidocalix[4]arenes which show a quite interesting reversed recognition behaviour, since they are able to recognise anions in organic media. We synthesised a series of macrobicyclic calix[4]arenes bearing peptide bridges containing a basic nitrogen group which can act, once protonated at physiological pH, as the ammonium group of Vancomycin. We explored the conditions to introduce furanose and pyranose moieties at the lower and upper rims of calix[4]arenes. The detertbutylated calix[4]arene reacted with diisopropylidene-α-furanose and with tetra-O-acetylated-α,β-glucopyranose to afford mono- and bisglycosylated compounds.