Twelve novel unsymmetrical cryptands (1-12) containing various units (methylene, 2- methylenylpropylene, pyridine2, 6-diyldimethylene, 0-and m-xylylene) each in two bridges have been synthesized by a onestep cyclization procedure. These cryptands were obtained by treating tetraalcohols 15-17, obtained from diethanolamine and diglycolyl dichloride followed by reduction or from diethanolamine and the appropriate oligoethylene glycol ...