Novel biscalix[4]arene derivatives where two calixarene units are connected via one or two ureido bridges on the upper rim has been prepared. These compounds represent well preorganised cavities with interesting complexation abilities towards anions. The structure of bis-ureido derivative was proved by X-ray crystallography. (C) 2002 Elsevier Science Ltd. All rights reserved.
Novel biscalix[4]arene derivatives where two calixarene units are connected via one or two ureido bridges on the upper rim has been prepared. These compounds represent well preorganised cavities with interesting complexation abilities towards anions. The structure of bis-ureido derivative was proved by X-ray crystallography. (C) 2002 Elsevier Science Ltd. All rights reserved.