title: Supramolecular phosphatases formed by the self-assembly of the bis(Zn²⁺-cyclen) complex, copper(II), and barbital derivatives in water.
abstract: In our previous paper, we reported that a dimeric Zn(2+) complex with a 2,2'-bipyridyl linker (Zn2L(1)), cyanuric acid (CA), and a Cu(2+) ion automatically assemble in aqueous solution to form 4:4:4 complex 3, which selectively catalyzes the hydrolysis of mono(4-nitrophenyl)phosphate (MNP) at neutral pH. Herein, we report that the use of barbital (Bar) instead of CA for the self-assembly with Zn2L(1) and Cu(2+) induces 2:2:2 complexation of these components, and not the 4:4:4 complex, to form supramolecular complex 6 a, the structure and equilibrium characteristics of which were studied by analytical and physical measurements. The finding show that 6 a also accelerates the hydrolysis of MNP, similarly to 3. Moreover, inspired by the crystal structure of 6 a, we prepared barbital units that contain functional groups on their side chains in an attempt to produce supramolecular phosphatases that possess functional groups near the Cu2(μ-OH)2 catalytic core so as to mimic the catalytic center of alkaline phosphatase (AP).
authors: Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan), Fax: (+81) 4-7121-3670; Faculty of Pharmacy, Universiti Teknologi MARA, Puncak Alam, Selangor 42300 (Malaysia).
authors: Mohd
authors: M
authors: Zulkefeli
authors: Yosuke
authors: Y
authors: Hisamatsu
authors: Asami
authors: A
authors: Suzuki
authors: Yuya
authors: Y
authors: Miyazawa
authors: Motoo
authors: M
authors: Shiro
authors: Shin
authors: S
authors: Aoki
mesh_terms: D001462:Barbital / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D000080027:Cyclams; D006571:Heterocyclic Compounds / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D014867:Water / Q000737:chemistry; D015032:Zinc / Q000737:chemistry*
chemical_list: D000080027:Cyclams; D006571:Heterocyclic Compounds; D014867:Water; D001462:Barbital; D003300:Copper; C038072:cyclen; D015032:Zinc
keywords: copper; hydrolysis; self-assembly; supramolecular chemistry; zinc