Study On The Synthesis, Structure And Properties Of Porphyrin And Heterocyclic Amino Acid Schiff Base Tin Compounds

The porphyrintin and organotin compounds have received widespread attention because of their applications in the catalysis,drugs,and materials in the recent years.In this thesis,a series of nitrogen heterocyclic tin compounds possessing novel structure were synthesized by the aryl porphyrins and heterocyclic amino-acid?L-histidine and L-tryptophan?Schiff bases as ligands,and characterized by means of nuclear magnetic resonance spectroscopy,infrared spectroscopy and X-ray single crystal diffraction techniques.The structural features,photo-physical properties,electrochemical properties,anti-cancer activity and interactions with bio-macromolecule DNA have been studied.The tetraarylporphyrintin chlorides,?4-RTPP?SnCl₂?R=Me,t-Bu?,were prepared by the reactions of 5,10,15,20-tetra?4-methylphenyl?porphyrin?4-MeTPP?,5,10,15,20-tetra-?4-t-butylphenyl?porphyrin?4-t-BuTPP?with stannous chloride in pyridine.After the hydrolysis,the porphyrintin hydroxides??4-RTPP?Sn?OH?2?were obtained.29 new trans-bis?carboxylato?-?5,10,15,20-tetraphenylporphyrinato?tin compounds,?4-RTPP?Sn?OCOR'?2?R'=Ph,PhCH=CH,PhC?OH?H,2-HOC₆H₄,2-CH₃C₆H₄,2-NH₂C₆H₄,2-ClC₆H₄,3,5-?NO₂?₂-2-HOC₆H₂,CF₃,CH₂=CH,CH₃OCH₂,PhCONHCH₂,Py,etc.?,were synthesized by the reaction of the different carboxylic acids with the porphyrintin hydroxides.Their structures were characterized by IR,¹H and ¹³C NMR,and X-ray single crystal diffraction.The crystal structures of 11 porphyrintin compounds were analyzed.The tin atom has an octahedral coordination geometry formed by the four nitrogen atoms of the porphyrinato group and the two monodentate carboxylate ions occupied the axial positions.The ultraviolet spectrum indicate there are a strong Soret band at about 427nm.And the fluorescence spectra manifest the excitation wavelengths are at 370nm.The cyclic voltammetry curve of three compounds show that compounds which react with organic acid were oxidized easierly.The crystal structures of 11 compounds were measured by X-ray single crystal diffraction.Four compounds could interact with calf-thymus DNA.Twenty two organotin derivatives,R2Sn?2-O-3-Z-4-Y-5-XC6HCH=NCH?R'?COO??R=Me,Et,Bu,Ph;R'=CH2In,CH2Im;X,Y,Z=H,Br,CH,OCH3?,have been synthesized by the reaction of diorganotin chlorides with the Schiff bases derived from heterocyclic amino-acid?L-histidine and L-tryptophan?and substituted salicylaldehyde,and were characterized by IR,¹H and ¹³C NMR,and X-ray single crystal diffraction.The crystal structures of 12 compounds were determined.We discovered that the diorganotin complexes of L-histidine Schiff base have three structure types:1)the tin atom is in a 6-coordinated distorted octahedral geometry and form a five-and a six-membered chelate rings with a phenolic oxygen atom,a carboxylic oxygen atom,and imine nitrogen atom of the tridentate Schiff base ligand.The oxygen atom of methanol takes another coordination site;2)the tin atom is in a 6-coordinated distorted octahedral geometry and form one five-and two six-membered chelate rings with a phenolic oxygen atom,a carboxylic oxygen atom,an imine nitrogen atom and a imidazole nitrogen atom of the tetradentate Schiff base ligand.3)the tin atom is in a 5-coordinated distorted trigonal bipyramidal geometry and form a five-and a six-membered chelate rings with a phenolic oxygen atom,a carboxylic oxygen atom,and tetrahydropyridinenitrogenatomofthetridentate4-?2-hydroxyphenyl?-4,5,6,7-tetrahydro-1H-imidazo[4,5-c]pyridine-6-carboxylic acid ligand formed by the addition of imidazole C5-H to Schiff base C=N bond.Three structure types of diorganotin complexes of L-tryptophan Schiff base are as follows:1)the tin atom is in a5-coordinated distorted trigonal bipyramidal geometry and form one five-and a six-membered chelate rings with the ONO tridentate Schiff base ligand;2)the 6-coordinated dimmers containing a Sn₂O₂ four-membered ring were formed by the bridging coordination of carboxylic oxygen to tin atoms;3)the 6-coordinated chain polymer was produced by the bridging coordination of two oxygen atoms of carboxylic group to tin atoms.Many kinds of supramolecular structures were constructed by the intermolecular N-H…O hydrogen-bond between N-H from imidazole or pyrrole and carboxylic O atoms.When the reaction was carried out in dichloromethane,the configuration of chiral center of?-amino acid of L-tryptophan Schiff base was retained and the enantiomerically pure products were obtained,while in methanol,the racemization of chiral?-amino acid occurred and the racemic products were formed.Electrochemical properties of the compounds are confirmed by the cyclic voltammetry,and the experimental results show that nitrogen heterocyclic Schiff base tin compounds are more easily oxidized than nitrogen heterocyclic Schiff base compounds.The results of the cytotoxic assay of compounds show that the compounds have good activity against two human tumor cell lines,Hela?cervical cancer?and A549?lung cancer?.The best IC₅₀ value is 0.0086±0.005?M,and can be studied and optimized further as a lead compound.The ultraviolet absorption and fluorescence properties of the compounds have been measured,and the interaction with calf-thymus DNA was studied by the spectral methods.In this thesis,the syntheses,structures and properties of tin compounds of porphyrins and heterocyclic amino-acid Schiff bases were explored and studied.This work not only expands the contents of porphyrin and organotin chemistry and discovers many novel structural tin compounds,but also enriches the structural data of porphyrintin and organotin compounds and provides the experimental basis for further studying their properties and applications.