1. Structures and esterolytic reactivity of novel binuclear copper(II) complexes with reduced L-serine Schiff bases as mimic carboxylesterases.
- Author
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Zhang, Qin, Shu, Jun, Zhang, Yajun, Xu, Zhigang, Yue, Jian, Liu, Xiaoqiang, Xu, Bin, Chen, Zhongzhu, and Jiang, Weidong
- Subjects
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SCHIFF bases , *CARBOXYLESTERASES , *CATALYTIC hydrolysis , *ESTERS , *SERINE , *COPPER , *MICELLAR solutions - Abstract
Three novel binuclear copper(II) complexes with reduced L -serine Schiff bases were synthesized and their structures were analyzed with single-crystal X-ray diffraction and DFT calculations. The crystal data revealed that all of these binuclear complexes are chiral. Both 5-halogenated (bromo- and chloro-) binuclear complexes exhibit right-handed helix structural character. Interestingly, the 5-methyl-containing analogue has a two-dimensional pore structure. In this paper, the esterolysis reactivity of the as-prepared complexes shows that in the hydrolysis of p-nitrophenyl acetate (PNPA) these three complexes provide 26, 18, 40-fold rate acceleration as compared to the spontaneous hydrolysis of PNPA at pH 7.0, respectively. Under selected conditions, in excess buffered aqueous solution a rate enhancement by three orders of magnitude was observed for the catalytic hydrolysis of another carboxylic ester, p-nitrophenyl picolinate (PNPP). These complexes efficiently promoted PNPP hydrolysis in a micellar solution of cetyltrimethylammonium bromide (CTAB), giving rise to a rate enhancement in excess of four orders of magnitude, which is approximately 2.0–3.2 times higher than that in the buffer. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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