Analyses of 20-ns simulations of aqueous solutions of the recently synthesized cavitand benzotriborneol (BTB) show that this molecule binds a single water molecule within its hydrophilic cavity for an average time interval of ca. 750 ps, that is 370 times longer than the permanence time of water around borneol. Moreover, this time becomes three times longer in a 99.8% (V/V) chloroform-water solution, while it decreases for BTB methylether derivatives in water, becoming 279, 36 or 119 ps when one, two or all three hydroxyl hydrogen atoms are replaced by methyl groups, respectively. (c) 2006 Elsevier B.V. All rights reserved.