Synthesis, Structure, SOD Activity And Interaction With Albumin And Nucleic Acid Of Amino Acid Schiff Base Nickel Complexes

Schiff base ligands are considered“privileged ligands”because they are easily prepared by the condensation between aldehydes and imines.Stereogenic centres or other elements of chirality?e.g.,planes,axes?can be introduced in the synthetic design.Schiff base ligands are able to coordinate many different metals,and to stabilize them in various oxidation states,enabling the use of Schiff base metal complexes for a large variety of useful catalytic transformations.Practical guidelines for the preparation and use of different Schiff base metal complexes in the field of catalytic transformations are discussed in this tutorial review.The unique structure and properties of Schiff base ligands have demonstrated important values in spectroscopy,coordination chemistry,structure,stereoisomerism,catalysis,and photochromism.Nickel plays an important role in the metabolism of life.Therefore,more and more researchers pay attention to the biological activity and research value of Schiff-base nickel?II?complexes.DNA is a biological macromolecule that plays an important role in the storage,reproduction,and transmission of genetic information.It plays a decisive role in life processes such as growth,genetics,and mutation,and it can serve as a target for many drug molecules.Serum albumin plays an important role in the circulatory system of organisms.It can increase the apparent solubility of hydrophobic drugs in plasma and play a leading role in drug configuration and efficacy.The interaction between small molecule complexes and biological macromolecules can understand the link between the structure,function,and properties of metal complexes to explore the regulatory mechanisms in life processes.Therefore,research on this type of complex can strengthen the prevention and treatment of diseases.Moreover,it has important scientific value in the development of new drugs and design drug molecules.Ten new nickel?II?complexes have been synthesized and characterized by IR spectra.Their crystal structures have been determined by single crystal X-ray diffraction analysis.The mechanism of interaction between complexes and biological macromolecules?DNA and BSA?was explored by using a variety of spectroscopic methods or fluid mechanics.The ability of complexes to scavenge superoxide anion radicals was determined by the modified photoreduction of NBT.1.Three L-Serine schiff base nickel?II?complexes,[Ni?sal-L-Ser??bipy??CH₃OH?]?1??[Ni?naph-L-Ser??bipy??CH₃OH?]?2??[Ni?o-van-L-Ser??bipy??CH₃OH?]?3??sal-L-Ser=a Schiff base derived from salicylaldehyde and serine,naph-L-Ser=a Schiff base derived from 2-hydroxy-1-napthaldehyde and serine,o-van-L-Ser=a Schiff base derived from o-vanillin and serine,bipy=2,2-bipyridine?,have been synthesized and characterized by IR spectra.The single crystal X-ray diffraction showed that?1?,?2?and?3?belong to monoclinic crystal system,C2/c and P2?1?/c space group.The mechanism of interaction between complexes and biological macromolecules?DNA and BSA?was explored by using a variety of spectroscopic methods or fluid mechanics and the binding constants are K_b?1?=1.49×10⁴ L·mol^-1,K_b?2?=2.99×10⁴ L·mol^-1and K_b?3?=5.54×10⁴ L·mol^-11 and the quenching constants are K_sq?1?=0.37,K_sq?2?=0.61 and K_sq?3?=0.77.Complexes can cause static quenching of BSA and the quenching constants are K_sv?1?=4.40×10⁴ L·mol^-1,K_sv?2?=6.52×10⁴ L·mol^-11 and K_sv?3?=6.60×10⁴ L·mol^-1.The ability of complexes to scavenge superoxide anion radicals were determined by the modified photoreduction of NBT,the values of IC₅₀?1?is 54.0?mol·L^-1,IC₅₀?2?is 43.0?mol·L^-1 and IC₅₀?3?is 43.0?mol·L^-1.2.Two D-Tryptophan schiff base nickel?II?complexes,[Ni?naph-D-Trp??Phen??CH₃OH?]₂?2CH₃OH?4?and[Ni?o-van-D-Trp??Phen??CH₃OH?]₂?2CH₃OH?5??naph-D-Trp=a Schiff base derived from 2-hydroxy-1-napthaldehyde and tryptophan,o-van-D-Trp=a Schiff base derived from o-vanillin and tryptophan,phen=1,10-phenanthroline?,have been synthesized and characterized by IR spectra.The single crystal X-ray diffraction showed that?4?and?5?belong to monoclinic crystal system,C2 and P2?1?/c space group.The two complexes are all six-coordinated with Ni?II?centers and distorted octahedral configuration.The mechanism of interaction between complexes and biological macromolecules?DNA and BSA?was explored by using a variety of spectroscopic methods or fluid mechanics and the binding constants are K_b?4?=7.42×10⁴ L?mol^-11 and K_b?5?=1.71×10⁴ L?mol^-11 and the quenching constants are K_sq?4?=0.79 and K_sq?5?=0.66.Complexes can cause static quenching of BSA and the quenching constants are K_sv?4?=3.71?10⁵ L?mol^-1 and K_sv?5?=1.57?10⁵ L?mol^-1.The ability of complexes to scavenge superoxide anion radicals were determined by the modified photoreduction of NBT,the values of IC₅₀?4?is 44.0?mol·L^-1 and IC₅₀?5?is 59.0?mol·L^-1.3.OneL-Phenylalanineschiffbasenickel?II?complex,[Ni?naph-L-Phe??phen??CH₃OH?]?6??naph-L-Phe=a Schiff base derived from2-hydroxy-1-napthaldehyde and phenylalanine,phen=1,10-phenanthroline?,has been synthesized and characterized by IR spectra.The single crystal X-ray diffraction showed that?6?belong to Triclinic crystal system,P-1 space group.The complex is six-coordinated with Ni?II?centers and distorted octahedral configuration.The mechanism of interaction between complexes and biological macromolecules?DNA and BSA?was explored by using a variety of spectroscopic methods or fluid mechanics and the binding constants is K_b?6?=1.96×10⁴ L?mol^-1and the quenching constants are K_sq?6?=0.65.Complex can cause static quenching of BSA and the quenching constant is K_sv?6?=5.54?10⁴ L?mol^-1.The ability of complexes to scavenge superoxide anion radicals were determined by the modified photoreduction of NBT,the values of IC₅₀?6?is 56.0?mol·L^-1.4.Two L-Glycine schiff base nickel?II?complexes,[Ni?sal-Gly??Phen?]2?7?and[Ni?sal-Gly??Bipy?]2?8??sal-Gly=a Schiff base derived from salicylaldehyde and glycine,phen=1,10-phenanthroline,bipy=2,2-bipyridine?,have been synthesized and characterized by IR spectra.The single crystal X-ray diffraction showed that?7?and?8?belong to monoclinic crystal system,C2/c and P2?1?/c space group.The two complexes are all six-coordinated with Ni?II?centers and distorted octahedral configuration.The mechanism of interaction between complexes and biological macromolecules?DNA and BSA?was explored by using a variety of spectroscopic methods or fluid mechanics and the binding constants are K_b?7?=3.10×10⁴ L·mol^-1 and K_b?8?=1.24×10⁴ L·mol^-1and the quenching constants are K_sq?7?=0.94 and K_sq?8?=0.88.Complexes can cause static quenching of BSA and the quenching constants are K_sv?7?=6.21×10⁴ L·mol^-1 and K_sv?8?=5.83×10⁴ L·mol^-1.The ability of complexes to scavenge superoxide anion radicals were determined by the modified photoreduction of NBT,the values of IC₅₀?7?is 59.0?mol·L^-1and IC₅₀?8?is 52.0?mol·L^-1.