Journal of Clinical & Experimental Pharmacology

Na19 [NaAs4W40O140Pd4] *H2O a novel polyoxotungstate complex-synthesis and possible biological applications

Joint Meeting on International Conference on Pharmacology and Toxicology & 18^th International Conference on Medicinal and Pharmaceutical Chemistry

October 18-19, 2018 Dubai, UAE

Lavinia Berta, Andrei Gaz, Boda Francisc, Anca Mare, Adrian Man and Augustin Curticapean

University of Medicine and Pharmacy of Tirgu Mures, Romania

Posters & Accepted Abstracts: Clin Exp Pharmacol

Abstract:

Statement of the Problem: Polyoxotungstate are inorganic compounds with a broad range of pharmacological properties (antiviral, antibacterial, anti-tumoral activities). The purpose of this study was to synthesize Na19 [NaAs4W40O140Pd4 2+] *aq (As4W40Pd), a new Pd2+ complex of Na27 [NaAs4W40O140] aq (As4W40), a polyoxotungstate cryptand and to assess the antimicrobial activity. Method: The As4W40 cryptand was synthesized following methods already described in the literature. The complex was obtained by adding PdCl2 solution to As4W40 solution at pH 4, maintaining temperature between 70-80 ??�C. After purification the complex was analyzed by spectrometric methods, TGA, conductometry, X-ray diffractometry. The biological activity was studied in vitro on Gram positive and Gram negative bacterial strains by serial dilution method, with identification of Minimum Inhibitory (MIC) and Bactericidal Concentrations (MBC). Findings: The As4W40Pd complex structure is a Leyrie assembly which consist of 4 identical tri lacunar Keggin anion structures ([AsW9O33]9-) joined together by 4 WO6 octahedra in a ring-like form with high symmetry. The Pd2+ cation is central coordinated inside the structure, in active positions formed in the lacunar places with high electron density. In case of Pd complex a new vibration was noticed at 544 cm-1 corresponding to Pd-O bond. The results obtained by serial dilution method are the following (MIC, MBC=mg/ml): As4W40Pd for Methicillin-resistant Staphylococcus aureus (MRSA, ATCC 44003, Gram positive) MIC=1.48, MBC=1.48; for Pseudomonas aeruginosa (ATCC 27853, Gram negative) MIC=23.69, MBC=23.69; As4W40-for MRSA MIC=1.00, MBC=1.00 for P. aeruginosa MIC=64.60, MBC=no effect. Conclusion: A new complex was synthesized Na19 [NaAs4W40O140Pd4 2+]*34H2O. Both compounds exhibit remarkable antibacterial activity on strains resistant to current therapeutics. The complex was more efficient than the cryptand. MRSA have proved to be more sensitive than P. aeruginosa, which developed resistance to the cryptand. This class of compounds presents biological properties that deserve to be exploited and optimized further more. References 1. Moghayedi M, Goharshadi E K, Ghazvini K, Ahmadzadeh H, Ludwig R, Namayandeh-Jorabchi M (2017) Improving antibacterial activity of phosphomolybdic acid using graphene. Materials Chemistry and Physics; 188: 58-67. 2. Qi W, Qin Y, Qi Y, Guo L, Li J (2015) In vitro antitumor activity of a keggin vanadium-substituted polyoxomolybdate and its ctDNA binding properties. J. Chem.; 2015: 1-6. 3. Grama L, Man A, Muntean DL, Gaz Florea SA, Boda F, Curticapean A (2014) Antibacterial Activity of Some Saturated Polyoxotungstates. Romanian Review of Laboratory Medicine; 22(1): 111-118. 4. Hosseini S M, Amini E, Tavassoti Kheiri M, Mehrbod P, Shahidi M, Zabihi E (2012) Anti-influenza Activity of a Novel Polyoxometalate Derivative (POM-4960). Int. J. Mol. Cell. Med.; 1(1): 21-29. 5. Zhang D, Zhang C, Chen H, Ma P, Wang J, Niu J (2012) Syntheses, structures and properties of dimeric rare earth derivatives based on monovacant Keggin-type polyoxotungstates. Inorganica Chimica Acta; 391: 218-223.

Biography :

Lavinia Berta is working as a Lecturer at General and Inorganic Chemistry Department, Faculty of Pharmacy, University of Medicine and Pharmacy, Tirgu Mures, Romania. Her expertise is in the field of inorganic chemistry-synthesis, identification and characterization of poly-oxometallic compounds (UV-VIS, FT-IR, TGA and ICP). She has two national grants as Principal Investigator. She has many articles published and has participated in many national and international conferences.

E-mail: grama.lavinia@umftgm.ro