909025-03-2Relevant articles and documents
Hydrophilic Oligo(lactic acid)s Captured by a Hydrophobic Polyaromatic Cavity in Water
Kusaba, Shunsuke,Yamashina, Masahiro,Akita, Munetaka,Kikuchi, Takashi,Yoshizawa, Michito
, p. 3706 - 3710 (2018/03/05)
Biologically relevant hydrophilic molecules rarely interact with hydrophobic compounds and surfaces in water owing to effective hydration. Nevertheless, herein we report that the hydrophobic cavity of a polyaromatic capsule, formed through coordination-driven self-assembly, can encapsulate hydrophilic oligo(lactic acid)s in water with relatively high binding constants (up to Ka=3×105 m?1). X-ray crystallographic and ITC analyses revealed that the unusual host–guest behavior is caused by enthalpic stabilization through multiple CH–π and hydrogen-bonding interactions. The polyaromatic cavity stabilizes hydrolyzable cyclic di(lactic acid) and captures tetra(lactic acid) preferentially from a mixture of oligo(lactic acid)s even in water.
Unique cation binding capability of cyclic oligo(l-lactic acid) (l-COLA)
Kogame, Chizuru,Kida, Toshiyuki,Fujiwara, Tomoko,Akashi, Mitsuru
, p. 1675 - 1678 (2015/03/14)
Cyclic l-lactic acid octamer (l-COLA-8) shows a unique complexing capability towards alkali and alkali earth metal cations in acetonitrile-d3/chloroform-d (9/1). The valence of the cation affects the stoichiometry of the complexes between l-COLA-8 and the cation; l-COLA-8 forms a 2:1 complex with alkali metal cations, but forms a 1:1 complex with alkali earth metal cations. Additionally, l-COLA-8 shows a binding selectivity for Rb+ and Ba2+, which have a diameter about 3 ?.
