SOME NEW COORDINATION COMPOUNDS OF TIN (II) AND LEAD (II) WITH SCHIFF BASES REARRANGED FROM BENZOTHIAZOLINES

Transcription

1 Vol.3, o.3 (0), 449 I: ODE: RJABP OME EW OORDIATIO OMPOUD OF TI (II) AD LEAD (II) WIT IFF BAE REARRAGED FROM BEZOTIAZOLIE Arpita Verma, hilpa harma, K.B. Bansal, Manoj Kumar,. Varshney and A.K. Varshney Department of hemistry, University of Rajasthan,Jaipur3004 * ABTRAT The present paper is a report on the synthesis of some new coordination compounds of n(ii) and Pb(II) by the reactions of tin(ii) acetate/lead (II) acetate with sulfur containing ligands. Ligands used in these reactions are benzothiazolines prepared by the reaction of ptolualdehyde, 4acetylbiphenyl, 9anthraldehyde, 4 fluoroacetophenone and acetylfluorene with oaminothiophenol which on reaction with metal ion rearrange to chiff bases. haracterization and structure elucidation of the complexes are achieved by elemental analysis, electronic, infrared,, 3 MR and 9 n MR spectral studies. The potency of the synthesized compounds have been assessed by growth inhibiting potential of the complexes against variety of fungal and bacterial strains. Keywords: Tin (II) acetate; lead (II) acetate; oaminothiophenol; benzothiazolines ; spectral studies. IRODUTIO The condensation of oaminothiophenol with the carbonyl compounds should form the chiff base, but we get the benzothiazoline. These benzothiazolines when react with metal salts rearrange into chiff base with the formation of their coordination compounds. 3 3 Metal complexes of such ligands and particularly of sulfur containing ligands are drawing enormous attention mainly due to their practical utility. They are active against tuberculosis, cancer, viruses, malaria, smallpox and certain kinds of tumor. The role of metal chelates in all aspects of biological studies has gained considerable importance as these provide valuable approaches to the metabolic studies, oxidative phosphorylation, trans methylation and principles of chemotherapy. Recently, much interest has been shown in the synthesis of metal chelates of sulfur containing ligands and it is within this particular area that rather significant advances have been made 3. It was, therefore, considered worthwhile to synthesize such type of complexes by the reactions of tin (II) acetate and lead (II) acetate with benzothiazolines. EXPERIMETAL Analytical methods and physical measurements Tin and lead were estimated gravimetrically as no and lead sulphate respectively. itrogen and sulphur were estimated by Kjeldahl s method and Messenger s method, respectively 4. The electronic spectra were taken with a Toshniwal spectrophotometer in methanol. The IR spectra were recorded on FTIR EW OORDIATIO OMPOUD OF n(ii) AD Pb(II)

2 Vol.3, o.3 (0), 449 spectrophotometer using a model A400, himadzu in KBr pellets. and 3 MR spectra were recorded on JEOL AL300. ynthesis of ligands All the ligands were prepared by the condensation of aldehydes / ketones viz. ptolualdehyde, 4acetyl biphenyl, 9anthraldehyde, 4fluoroacetophenone and acetyl fluorene with oaminothiophenol in : molar ratio using absolute alcohol as the reaction medium. ynthesis of tin (II) and lead (II) complexes Tin (II) complexes were synthesized by the reaction of tin (II) acetate and benzothiazolines in : molar ratios in dry methanol as reaction medium. The resulting solution was stirred on magnetic stirrer for about two hours. The solvent was removed under reduced pressure and the product was finally dried in vacuo at 400. The physical properties and analytical data are recorded in Table Biological activity The antimicrobial activity of ligands and their corresponding tin (II) and lead (II) complexes are tested against fungi and bacteria (R.phaseoli, F. oxysporum,. aureus, E. coli, P.fluorescens etc.). The results also show that the resulting products are lipophilic in nature. The complexes are found to possess higher activity than ligands. The results of these studies show that the metal complexes are more active than the ligands and the data are recorded in Table.The fungitoxicity of the compounds increase with increase in concentration. REULT AD DIUIO The reactions of tin (II) acetate and lead (II) acetate with benzothiazolines in : molar ratio proceed in following manner :. n( 3 O O ) + 6 : n( ) + 3 O O M olar ratio. Pb( 3 O O ) + 6 : Pb( ) + 3 O O M olar ratio Where represents the donor sets of ligands. Electronic spectra The electronic spectra of the ligands exhibit two bands near 0 nm and 3 nm consistent with the typical spectrum of a benzothiazoline (cyclic form) moiety 67. These bands may be attributed to the φφ* and π π* benzenoid transitions. In the corresponding tin (II) complexes, an additional band around 40 nm due to n π* transition of the azomethine group is also observed. The formation of this new band may be due to the isomerization of benzothiozoline in to chiff bases. Infrared spectra In the solid state IR spectra of benzothiazoline,the presence of a strong and broad band due to v group in the region cm and absence of v at ~ cm is indicative of the benzothiazoline rather than the chiffbase structure.a new band at 0 cm is observed in the spectra of metal complexes due to the presence of v(=) vibrations. The appearance of this band suggests that the complexes are metal chiff base derivatives as the benzothiazoline ring rearranges to give the chiffbase derivatives in the presence of metal ion.the data are given in Table. MR spectra The proton magnetic resonance spectra of benzothiazolines show the proton signals at δ. ppm which disappear on complexation, indicating that the rearrangement of benzothiazoline form to the chiff base form has occurred. The ligand shows a complex multiplet in the region δ ppm for the EW OORDIATIO OMPOUD OF n(ii) AD Pb(II) 46

3 Vol.3, o.3 (0), 449 benzene protons and these remains at almost the same position in the spectra of complexes. The data are given in Table3. 3 MR spectra The 3 MR spectra of ligands and their corresponding tin (II) and lead (II) complexes have been recorded in Table4. The considerable shifts in position of carbons attached with sulfur and nitrogen clearly indicate the deprotonation of group and coordination of azomethine nitrogen to metal atom.the data are given in Table4. AKOWLEDGEMET Authors are thankful to the ead, Department of hemistry, University of Rajasthan, Jaipur for providing laboratory facilities and constant encouragement. hilpa harma and Manoj Kumar are thankful to IR ew Delhi for providing financial assistance. AKV and V are thankful to UG, Bhopal for providing financial assistance. REFEREE..Zhu, and T.Akiyama, Org. Lett., (), 40(09).. A.E.Graminha,.Rodrigues, A.A.Batista, L.R.Teixeira, E..Fagundes, and.beraldo, pectrochimica Acta Part A, 69, 073(0). 3..Bujdakova, and M.Mackova, Int. J. Antimicrob. Agents, 4, 303(994). 4. D.L.Klayman, J.F.Bartosevich,T.. Griffin,.J.Mason, and J.P.covill, J. Med. hem.,, (979).. M.iang, R.F.Rosenbusch,J.L.Virella, and M.LKaeberle,.,J.Vet.Diagn Invest,,34(999). 6..J.Pi,. Liu, W.Du, and W.P. Deng Tetrahedron Letters, 0, 49(09). 7. M.harma,.L.ingh,.Varshney, P.harma, and A.K. Varshney Phosphorus, ulfur and ilicon, 7, (03).. A.K.Varshney,.Varshney, M.harma, and.l.ingh Phosphorus, ulfur and ilicon,, 3(00). 9. M.Agrawal, J.P.Tandon, and R..Mehrotra ynth. React. Inorg. Met.Org. hem., 0(), 9(90). 0. W.Dansithong,.Paul,T.Mitsumoto,.aruhashi, and T. hinozawa,ancel Letters,4(),9(0). Y..Park,Y.G.Kim,J..hang, and D.Y.Kim, Korean Biochem. J.,6, 4(993) n 3 6 Fig. : 3 (L ) Fig. : n. EW OORDIATIO OMPOUD OF n(ii) AD Pb(II) 47

4 Vol.3, o.3 (0), Pb Fig. 3: Pb Table : Reactions of tin (II) acetate and lead (II) acetate with benzothiazolines.. o. ompounds Ligands Molar ratio Product colour & state. n( 3 OO) 3 : n( ) Yellowish cream solid. n( 3 OO) 7 : n( 40 3 ) 3. n( 3 OO) : n( 4 ) 4. n( 3 OO) F : n( F). n( 3 OO) : n( 4 ) ream solid 6. Pb( 3 OO) 3 : Pb ( ) 7. Pb( 3 OO) 7 : Pb ( 40 3 ) ream solid. Pb( 3 OO) : Pb ( 4 ) 9. Pb( 3 OO) F : Pb ( F) Melting point Analysis: Found (alcd.) % ( ) Pb/n (.77) 0. (.40).6 (.96) (9.4) 0.70 (.96) (3.40) 90.0 (.).40 (.90) (9.77) 4. (4.90) 3.7 (3.7) 3.66 (3.76) 4.40 (4.6) 3.6 (3.76) 3.99 (4.).9 (3.44) 3.6 (3.36) 3.9 (4.0) 0.0 (.).0 (.6).30 (.6) 0. (0.).3 (.6) 9.70 (9.7) 7.0 (7.9) 7.40 (7.70).9 (9.) Molecular weight: Found (alcd.) 6.33 (7.3) 703. (73.) (743.49) (607.9) 743. (743.49) 64. (69.) 0.0 (.0) 3.0 (3.99) 69.0 (69.79) Table: Antimicrobial activity of benzothiazolines and their corresponding tin (II) and lead (II) complexes. Microorganisms F. IZ oxysporum R.phaseoli IZ P. IZ fluorescens E.coli IZ. aureus IZ L n. Pb. L n Pb ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm (`0.0) (0.7) (0.4) (0.7) (0.4) (0.0) (0.3) (0.7) (0.7) (0.37) (0.0) (0.6) (0.66) (0.7) (0.66) (0.6) (0.7) (0.6) (0.7) (0.6) (0.7) 4 (0.) (0.44) 6 (0.4) (0.46) (0.3) (0.0) (0.66) 0 (0.7) (0.6) (.00) 0 (0.6) 0 (0.7) (0.6) (.33) (0.7) (0.) (.33) (0.7) (.00) (.) (0.4) (.) (0.7) (0.) (0.7) 6 (.44) EW OORDIATIO OMPOUD OF n(ii) AD Pb(II) 4

5 Vol.3, o.3 (0), 449 IZ = Inhibition zone (diameter in mm); AI = Activity index (Inhibition zone of test compounds/inhibition zone of standard) L = 3 ; L = 7 Table3: ome important IR spectral data of benzothiazolines and their corresponding tin (II) and lead (II) complexes.. o. ompounds v= v/o vn / vpb. L ( 3 ) n ( ) Pb ( ) 70 w 4. L ( 7 ) n( 40 3 ) Pb( 40 3 ) 90 0w w = weak Table4: 3 MR spectral data (δ ppm) of benzothiazolines and their corresponding tin (II) and lead (II) complexes. hemical shifts in δ ppm ompounds (L ) n Pb Table: uclear magnetic resonance data for the benzothiazoline and the corresponding tin and lead complexes in δ ppm. ompound = Aromatic protons L ( 3 ) n ( ) Pb ( ) L ( 7 ) n ( 40 3 ) Pb ( 40 3 ) L ( ) n ( 4 ) Pb ( 4 ) (Received: 7 August 0 Accepted: 0 eptember 0 RJ633) Adopt GREE EMITRY ave Our Planet. We publish papers of Green hemistry on priority If you think that you may be a potential reviewer in field of your interest, write us at rasayanjournal@gmail.com with your detailed resume and recent color photograph. EW OORDIATIO OMPOUD OF n(ii) AD Pb(II) 49