Studies On The Synthesis, Characterization And Biological Activity Of 2-amino Pyrimidine Schiff Base Complexes

Schiff base metal complexes because of their multiple stuctures and widely uses become more and more important in the field of bioactivity, catalysis and material atc.Thus, study on the synthesis of novel Schiff base coordination polymers and their characterization and application has crucial significance.In this paper, there were three ligands derived from 2-amino pyrimidine and 2-hydroxy -1-naphthaldehyde, o-vanillin or salicylaldehyde and their 8 transition metal complexes and 4 lanthanidenitrate metal complexes were synthesized.The ligands and complexes'structures were characterized by IR spectroscopy,UV-Vis spectroscopy, 1^HNMR analysis ,elemental analysis and thermal gravimetric analysis, molar conductance analysisand so on. According to the above speculate, we know the complexes'suggested strctures .The binding mode of the [CuL²(NO₃)(C₂H₅OH)]·2H₂O with DNA and its anticancer activity has been investigated.The details of contents are as follow:(1) The ligand (HL¹) and 4 transition or lanthanidenitrate metal complexes derived from 2-amino pyrimidine and 2-hydroxy-1-naphthaldehyde were synthetized. The composition of the complexes are confirmed to be: [CuL¹(NO₃)(C₂H₅OH)]·3H₂O, [CoL¹(NO₃)(C₂H₅OH)]·3H₂O,[ErL¹(NO₃)(C₂H₅OH)(H₂O)]·H₂O,[YL¹(NO₃)(C₂H₅OH)(H₂O)]·2H₂O.(2) The ligand (HL²) and 4 transition or lanthanidenitrate metal complexes derived from 2-amino pyrimidine and o-vanillin were synthetized. The composition of the complexes are confirmed to be:[CuL²(NO₃)(C₂H₅OH)]·2H₂O,[MnL²(CH₃COO) (C₂H₅OH)]·3H₂O,[YL²(NO₃)(C₂H₅OH)(H₂O)]·H₂O,[YbL²(NO₃)(C₂H₅OH)(H₂O)₂]·H₂O.(3) The ligand (HL³) and 4 transition metal complexes derived from 2-amino pyrimidine and salicylaldehyde were synthetized. The composition of the complexes are confirmed to be:[CuL³(CH₃COO)(C₂H₅OH)]·3H₂O,[NiL³ (CH₃COO)(C₂H₅OH)]·3 H₂O,[CoL³(CH₃COO)(C₂H₅OH)]·2H₂O,[MnL³ (CH₃COO)(C₂H₅OH)]·3H₂O.All of the ligands and complexes are colored, powered substances, stable and can be stored in the air for a very long time. The transition ion is six-coordinated with a octagonal geometry, and the lanthanidenitrates ion is seven coordinated and eight-coordinated.The two nitrogen atom (one from the -C=N-, the other from the pyrimidine), hydroxybenzene's oxygen atom in the ligand are all coordinated , the nitric acid and Carboxyl acid are all coordinated to the ions in a bidentate pattern, the oxygen atom of C₂H₅OH is coordinated to the ions too.Water molecules are existing as crystal water coordinated or lied in crystal substances.(4) Contrasting Coats-Redfern integral and Achar differential method, the complexes'second calculating process of thermal decomposition was calculated. The kinetic equations of corresponding kinetic parameters were acquired.The kinetic parameters are including E, A, order of reaction and correlation coefficient etc. Theâ–³S^≠andâ–³G^≠for the second thermal decomposition steps were also obtained. In the paper , the discussing complexes were all thermal decomposition kinetic function in step(2) which can be expressed as f(α)=1/2(1-α)[-ln(1-α)]^-1,and at the same time the kinetic equation of thermal decomposition may be expressed as:dα/dt=A·exp(-E/RT)·f(α)=A·exp(-E/RT)·1/2(1-α)[-ln(1-α)]^-1.Regarding to the complex [YL¹(NO₃)(C₂H₅OH)(H₂O)]·2H₂O ,E=81.92 kJ·mol^-1,lnA=27.15,r=0.9997,â–³S^≠=7.352 J·mol^-1·k^-1,â–³G^≠=77.82 kJ·mol^-1.Regarding to the complex [CuL²(NO₃)(C₂H₅OH)]·2H₂O E=67.75 kJ·mol^-1,lnA=29.17,r=0.9762,â–³S^≠=6.071 J·mol^-1·k^-1,â–³G^≠=64.30 kJ·mol^-1.Regarding to the complex [CoL³(CH₃COO)(C₂H₅OH)]·2H₂O,E=61.73 kJ·mol^-1,lnA=27.19,r=0.9938,â–³S^≠=22.97 J·mol^-1·k^-1,â–³G^≠=50.48 kJ·mol^-1.(5) The fluorescence properties of all ligands and part of complexes with were discussed. The emission and excitation peak wavelengths (λ_ex/λ_em) of [CuL¹(NO₃)(C₂H₅OH)]·3H₂O,[ErL¹(NO₃)(C₂H₅OH)(H₂O)]·2H₂O,[CuL²(NO₃) (C₂H₅OH)]·2H₂O,[CuL³(CH₃COO)(C₂H₅OH)]·3H₂O partly in fluorescence spectra are 282 nm/349 nm,349 nm/462 nm,307 nm/409 nm,289 nm/382 nm. The emission peaks and excitation peaks are all changed. It is proving that the fluorescence intensity of the complexes increased obviously.(6)The interaction of the [CuL²(NO₃)(C₂H₅OH)]·2H₂O with DNA has been investigated by UV-Vis spectrometry ,fluorescence spectrometry,viscosity and electrochemical behavior.The rusults show that the interaction of the complex with DNA belong to intercalation mode,and the binding constant for the complex was K_b=8.12×10⁴ L·mol^-1.(7)It were studied by MTT method about some of the above complexes'antiproliferaion activities in human prostate cancer PC-3 cells.It was found that [CuL² (NO₃)(C₂H₅OH)]·2H₂O revealed the better antiproliferation activity.So we chose Cu(â…¡) complex for further anticancer researches ,and in the end we found that the Cu(â…¡) complex could inhibit CT-like activity,inhance Caspase-3 activity and induce apoptosis in prostate cancer PC-3 cells and in a concentration and time-dependent manner.