Synthesis and properties of pentahomothiazacalix[3]arene derivatives constructed from phenol-formaldehyde trimer and aminoethanethiol unit

Chiral calixarene analogs incorporating aminoethanethiol unit such as L-cysteine alkyl ester into their rings were prepared. NMR studies of the macrocycles reveal that their preferred conformations in solution are a cone form and the introduction of aminoethanethiol unit in their rings causes the ring fluctuation.