Synthesis, characterization, and biological activity of coordination polymers derived from pyromellitic dianhydride

A new ligand, 2,5-bis(furan-2-ylmethylcarbamoyl)terephthalic acid (BFMTA), was synthesized using 1,2,4,5- benzenetetracarboxylic dianhydride (pyromellitic dianhydride-PMDA) with furan-2-ylmethanamine (2-furfurylamine). New coordination polymers of the ligand (BFMTA) were also prepared using transition metal ions Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) metal salts. The coordination polymers and ligand were characterized by physicochemical characteristics, magnetic susceptibilities, spectroscopic investigations, and thermogravimetry.

Turkish Journal of Chemistry http://journals.tubitak.gov.tr/chem/ Research Article Turk J Chem (2013) 37: 978 986 ă ITAK c TUB ⃝ doi:10.3906/kim-1206-22 Synthesis, characterization, and biological activity of coordination polymers derived from pyromellitic dianhydride Yogesh Shantilal PATEL,1 Ritu Bharat DIXIT,2 Hasmukh Shanubhai PATEL1,∗ Department of Chemistry, Sardar Patel University, Vallabh Vidyanagar, Gujarat, India Ashok & Rita Patel Institute of Integrated Studies and Research in Biotechnology and Allied Sciences, New Vallabh Vidyanagar, Gujarat, India Received: 12.06.2012 • Accepted: 11.06.2013 • Published Online: 04.11.2013 • Printed: 29.11.2013 Abstract: A new ligand, 2,5-bis(furan-2-ylmethylcarbamoyl)terephthalic acid (BFMTA), was synthesized using 1,2,4,5benzenetetracarboxylic dianhydride (pyromellitic dianhydride-PMDA) with furan-2-ylmethanamine (2-furfurylamine) New coordination polymers of the ligand (BFMTA) were also prepared using transition metal ions Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) metal salts The coordination polymers and ligand were characterized by physicochemical characteristics, magnetic susceptibilities, spectroscopic investigations, and thermogravimetry Antimicrobial activity was tested using the agar-plate method against various strains of bacteria and spores of fungi The results showed significantly higher antimicrobial activity of coordination polymers compared to the ligand Key words: Coordination polymer, spectral studies, thermogravimetric analysis (TGA), biological activity Introduction The metal–organic framework (MOF) architecture has witnessed a tremendous growth because of its intriguing structures and potential properties Much research is being devoted to the preparation of a polymeric chain by the formation of metallic chelates Some success has been achieved in the preparation of coordination polymers from bi-functional ligands MOFs derived from bisamic acid have received less attention, apart from bisamic acid based on maleic anhydride, and amic acid based on phthalic anhydride 2−4 More particularly, multicarboxylate material shows good building blocks in the design of MOFs with desired topologies owing to their rich coordination modes Therefore, the dianhydride of 1,2,4,5-benzenetetracarboxylic acid (pyromellitic dianhydride) has been selected for further work It is also used extensively as an important monomer in the preparation of a variety of polymers Moreover, it is useful in the preparation of high performance coatings that have been widely employed in many fields because of its excellent thermal and oxidative stability and excellent mechanical properties 5−7 This may offer the compound both metal gripping potentiality and good biological efficacy due to anhydride moiety The MOF based on bisamic acid of pyromellitic dianhydride has not attracted any attention Hence, the initial work in this direction has been reported by us recently 8,9 This prompted us to extend our work by using other auxiliary ligands such as 2,5-bis(furan-2-ylmethylcarbamoyl)terephthalicacid (BFMTA) Considering the special biological activity along with its properties, we have focused our work on this ligand by complexation using Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) metal ions ∗ Correspondence: 978 drhspatel786@yahoo.com PATEL et al./Turk J Chem Experimental All common reagents and solvents used were of analytical grade Alumina supported pre-coated silica gel 60 F254 thin layer chromatography (TLC) plates were purchased from E Merck (India) Limited, Mumbai, and were used to check the purity of compounds and to study the progress of the reaction, whereby TLC plates were illuminated under ultraviolet light (254 nm), evaluated in I vapors, and visualized by spraying with Draggendorff’s reagent Infrared spectra (FT-IR) were obtained from KBr pellets in the range of 4000–400 cm −1 with a PerkinElmer spectrum GX spectrophotometer (FT-IR) 13 H NMR and C NMR spectra were acquired at 400 MHz on a Bruker NMR spectrometer using DMSO-d6 (residual peak at δ ∼2.5 or ∼ 39.5 ppm, 300 K) as a solvent as well as TMS an internal reference standard Microanalytical (C, N, H) data were obtained using a PerkinElmer 2400 CHN elemental analyzer The solid diffuse electronic spectra were recorded on a Beckman DK-2A spectrophotometer with a solid reflectance attachment MgO was employed as a reference Magnetic moments 10 were determined by the Gouy method with mercury tetrathiocyaneto cobaltate(II), with [HgCo(NCS) ] as calibrant (Xg = 1644 × 10 −6 cgs units at 20 ◦ C), by Citizen balance 11 (at room temperature) Molar susceptibilities were corrected using Pascal’s constant The thermogravimetric analysis studies were carried out with a PerkinElmer thermogravimetry analyzer at a heating rate of 10 ◦ C −1 in the temperature range 50–700 ◦ C under nitrogen The metal content of the coordination polymers was determined by decomposing a weighed amount of each coordination polymer with HClO , H SO , and HNO (1:1.5:2.5) mixture followed by standard EDTA titration 12 The number-average molecular weight (Mn) of coordination polymers was determined by nonaqueous conductometric titration It was carried out in pyridine solution against standard sodium methoxide in pyridine solution as titrant The number-average molecular weight of each sample was calculated as reported in the literature 13 and the results are shown in Table The melting point was determined by the standard open capillary method Table Physicochemical parameters of the ligand and its coordination polymers Empirical formula of compound BFMTA C20 H16 N2 O8 [Mn(BFMTA)H2 O)2 ]n C20 H19 N2 O10 Mn [Fe(BFMTA)(H2 O)2 ]n C20 H19 N2 O10 Fe [Co(BFMTA)(H2 O)2 ]n C20 H19 N2 O10 Co [Ni(BFMTA)(H2 O)2 ]n C20 H19 N2 O10 Ni [Cu(BFMTA)(H2 O)2 ]n C20 H19 N2 O10 Cu [Zn(BFMTA)(H2 O)2 ]n C20 H19 N2 O10 Zn a Empirical weight (g) Color Yield % M.P.a (◦ C) 412.35 light yellow 75 260 502.31 white 45 450 52 439 49 437 57 464 503.22 506.31 506.07 light brown light pink light green 510.92 green 65 474 512.78 white 40 453 Elemental analysis C H 58.25 3.91 (58.02) (3.76) 47.82 3.81 (47.58) (3.69) 47.74 3.81 (47.49) (3.68) 47.44 3.78 (47.28) (3.61) 47.47 3.78 (47.21) (3.61) 47.02 3.75 (46.87) (3.51) 46.85 3.73 (46.69) (3.62) calc (found %) N M 6.79 — (6.52) 5.58 10.94 (5.41) (10.71) 5.57 11.10 (5.21) (10.88) 5.53 11.64 (5.39) (11.48) 5.54 11.60 (5.42) (11.39) 5.48 12.44 (5.31) (12.36) 5.46 12.76 (5.33) (12.59) µef f B.M Mn DP — — — 5.34 2975 5.13 2976 4.65 2512 2.89 2489 2.67 3039 D 2511 The melting points were checked by standard open capillary method and are uncorrected, µef f B.M.: Magnetic moment M n Number average molecular weights, DP: Degree of polymerization, D: Diamagnetic 2.1 Preparation of 2,5-bis(furan-2-ylmethylcarbamoyl)terephthalicacid (BFMTA) Adding dropwise a solution of furan-2-ylmethanamine (19.43 g, 0.2 mol) to a stirred solution of pyromellitic dianhydride (21.813 g, 0.1 mol) and keeping the temperature of the medium close to 0–5 ◦ C for h (Scheme), 979 PATEL et al./Turk J Chem the solution obtained was poured into ice water in which the reaction product precipitated The final white precipitates were filtered, washed, and purified by column chromatography Yield was 65%; M Wt 412.35 g; Decomposition temp.: 250–260 ◦ C (uncorrected); Elemental Analysis Calculated for C 20 H 16 N O : C 58.25, H 3.91, N 6.79% Found: C 57.87, H 3.75, N 6.58%; H NMR (DMSO- d6 , δ ppm): 10.93 (s, 2H, -COOH), 8.90 (t, J = 5.2 Hz, 2H, -NH-CO-), 8.12 (s, 2H, Ar.H), 7.49–7.93 (m, 6H, Ar.H), 4.32 (d, J = 5.2 Hz, 4H, -CH -); DEPT-135 (DMSO-d6 , δ ppm): 42.24, 117.78, 119.24, 123.46, 126.10, 129.33; EI MS m/z: 413.23 [M + H] + O O O O + O O O pyromellitic dianhydride NH2 furan-2-yl methanamine 0-5 °C O O O OH NH NH HO O O O 2,5-bis((furan-2-ylmethyl)carbamoyl)terephthalic acid (BFMTA) metal ion O H2O O H2O O O NH M M NH O H2O O O O H2O n Co-ordination polymers M=Mn(II),Fe(II),Co(II),Ni(II),Cu(II),Zn(II) Scheme Synthetic route for the coordination polymers 2.2 Preparation of coordination polymers All the coordination polymers were synthesized by using equimolar amounts of ligand and metal salt A warm and clear solution of BFMTA (4.1235 g, 0.01 mol) in dimethylsulfoxide was neutralized by adding dropwise 0.1 M sodium hydroxide solution When a pasty mass was observed, it was diluted with water to make the solution clear To the above solution was added a solution of copper acetate (1.997 g, 0.01 mol) with constant stirring and the pH of the reaction mixture was adjusted to 4–5 The BFMTA-Cu 2+ coordination polymer thus separated out in the form of a suspension was digested on a water bath for h, filtered, washed, and dried in air at room temperature The BFMTA-Cu 2+ polymer is insoluble in common organic solvents like methanol, 980 PATEL et al./Turk J Chem ethanol, chloroform, acetone, and benzene A similar procedure was followed to prepare other coordination polymers such as BFMTA-Mn 2+ , BFMTA-Fe 2+ , BFMTA-Co 2+ , BFMTA-Ni 2+ , and BFMTA-Zn 2+ by using their respective salts and maintaining pH accordingly The synthetic route is shown in the Scheme Results and discussion 3.1 Characterization of 2,5-bis(furan-2-ylmethylcarbamoyl)terephthalicacid (BFMTA) To the best of our knowledge, BFMTA has not been reported previously The characterization of the reaction product provided the first unambiguous proof of the successful synthesis of BFMTA The FTIR spectrum of BFMTA showed the most relevant peaks of the furan ring and 1,2,4,5-tetra substituted benzene ring, other than typical absorptions arising from the band at 3528 cm −1 and 1711 cm −1 for carboxylic acid and 3254 cm −1 and 1680 cm −1 for the O =C-NH group 14 In the H NMR spectroscopy (Figure 1), the signals in the range of 7.49–7.93 ppm were ascribed to the protons of the aromatic rings The singlet at 10.93 ppm was ascribed to the protons of the carboxylic -OH group and the triplet at 8.90 ppm was attributed to the -NH proton of the amide group, which was further confirmed by DEPT-135 values In the DEPT-135 spectrum of BFMTA (Figure 2), the inverted peak at 42.24 ppm indicated a methylene bridge between the amide and furan ring The peaks at 126.10 ppm and 129.33 ppm indicated the carbonyl carbon of amide and carboxylic functionality Peaks of substituted carbon of aromatic rings were not observed while the peaks of unsubstituted aromatic carbon were observed at 117.78, 119.24, and 123.46 in the DEPT-135 spectra The monomer BFMTA started to lose weight because of thermal degradation The thermogram of the product BFMTA (Figure 3) indicated that the degradation occurred into steps The first stage of degradation, from 180 to 300 ◦ C, might be attributed to decarboxylation of the product BFMTA The value of wt loss 20.91% is consistent with the theoretical value 21.34% The second major stage, at about 300 to 700 ◦ C, was attributed to the monomer decomposition/pyrolysis The 3% to 4% char residue remained at 700 ◦ C The expected structure was thus clearly verified by the spectroscopic and thermal analysis, which indicated moreover the absence of any detectable impurity, particularly of the reagents used to prepare BFMTA 3.2 Characterization of coordination polymers Elemental analysis (Table 1) of the coordination polymers is in good agreement with the proposed structures All the coordination polymers exhibited 1:1 metal to ligand stoichiometry The structures of the coordination polymers are consistent with the FTIR, electronic spectra, and TGA The geometry of the central metal ion was confirmed by electronic spectra and magnetic susceptibility measurements The degrees of polymerization (DP) for all the coordination polymers are in the range of to All the data provide good evidence that the chelates are polymeric in nature The suggested structure of the coordination polymers is shown in the Scheme A comparison of the IR spectra (Table 2) of the ligand and its metal (II) coordinated polymers showed some significant characteristic differences Considerable differences to be expected were the band at about 3530 cm −1 for carboxylic acid in ligand that was virtually absent from the spectra of polymers and the presence of a more broadened band in the region near 3000 cm −1 for the coordinated polymers As the oxygen atom of the OH group of the ligand forms a coordination bond with the metal ions, the broadening of this band may be attributed to the presence of coordinated water molecules 15 The asymmetric and symmetric stretching frequencies of the carboxylate ion in the polymers were shifted to lower frequencies The C–O also registered a significant shift to lower frequency, indicating the participation of metal through carboxylate oxygen 16 Vibrational bands for O= C–NH (amide carbonyl linkage) shifted to lower frequencies, indicating the coordination of amide nitrogen 981 PATEL et al./Turk J Chem Figure NMR of 2,5-bis(furan-2-ylmethylcarbamoyl)terephthalic acid (BFMTA) Figure DEPT of 2,5-bis(furan-2-ylmethylcarbamoyl)terephthalic acid (BFMTA) to metal ion, and this can be explained by the donation of electrons from nitrogen to metal atom 17 The presence of a sharp band in the region of 525–535 cm −1 can be assigned to ν (M-N), 18 which indicated the involvement of nitrogen in coordination A medium intensity band for ν (M-O) 19 was observed at 625–640 cm −1 due to M-O coordination These features confirmed the proposed structure of coordination polymers 982 — — — — [Mn(BFMTA)H2 O)2 ]n [Fe(BFMTA)(H2 O)2 ]n [Co(BFMTA)(H2 O)2 ]n [Ni(BFMTA)(H2 O)2 ]n [Zn(BFMTA)(H2 O)2 ]n — — 3528 BFMTA [Cu(BFMTA)(H2 O)2 ]n C=O-OH Compound 3237 2980 3004 2991 3231 3231 3238 2980 2997 2989 — -OH 3239 3228 3235 3254 O=C-NH 1698 1696 1697 1693 1690 1692 1711 -C=O 1666 1667 1661 1665 1671 1663 1680 O=C-NH 1449 1452 1453 1448 1450 1451 1465 COO− 1027 1025 1022 1021 1019 1021 1039 C-O 639 625 633 640 627 632 — M-O 527 536 529 528 535 530 — M-N Electronic spectral data cm− Transitions — — 16,486 6A1g →4T 1g (4G), 17,710 6A1g →4T 2g (4G) 23,179 6A1g → 4A1g , 4Eg 19,038 5T 2g (F)→3Eg 36,022 5T 2g (F)→3T 1g 9830 4T 1g (F)→4T 2g (F) 15,520 4T 1g (F)→4A2g (F) 22,941 4T 1g (F)→4T 1g (P) 9891 3A2g →3T 2g 15,584 3A2g →3T 1g (F) 22,978 3A2g →3T 1g (P) 15,922 2T 2g →2Eg 22,757 charge transfer — — Table FTIR and electronic spectral data of the ligand and its coordination polymers (in cm − ) PATEL et al./Turk J Chem 983 PATEL et al./Turk J Chem The information regarding geometry of the coordination polymers was obtained from their electronic spectral data and magnetic moment values The diffuse electronic spectrum of the [Cu(BFMTA)(H O) ] n shows broad bands around 15,922 cm −1 and 22,757 cm −1 due to the T 2g →2 E g transition; the second may be due to charge transfer This suggests a distorted octahedral structure for the [Cu(BFMTA)(H O) ] n polymer The [Ni(BFMTA)(H O) ] n coordination polymer shows absorption bands at 15,584 cm −1 , 22,978 cm −1 , and 9891 cm −1 due to A 2g →3 T 1g (F), A 2g →3 T 1g (P), and A 2g →3 T 2g respectively The [Co(BFMTA)(H O) ] n polymer shows absorption bands at 22,941 cm −1 , 15,520 cm −1 , and 9830 cm −1 corresponding to T 1g (F) →4 T 1g (P), T 1g (F) →4 A 2g (F), and T 1g (F) →4 T 2g (F) transitions, respectively, indicating an octahedral configuration for the [Ni(BFMTA)(H O) ] n and [Co(BFMTA)(H O) ] n polymers 20 The spectrum of [Fe(BFMTA) (H O) ] n shows bands at 36,022 cm −1 and 19,038 cm −1 assigned to the transitions T 2g (F) →3 T 1g and T 2g (F) →3 E g , suggesting an octahedral configuration The spectrum of [Mn(BFMTA)(H O) ] n shows weak bands at 16,486 cm −1 , 17,710 cm −1 , and 23,179 cm −1 assigned to the transitions A 1g →4 T 1g (4G), A 1g →4 T 2g (4G), and A 1g →4 A 1g , E g respectively, suggesting an octahedral structure for the [Mn(BFMTA)(H O) ] n polymer 21 The spectrum of the [Zn(BFMTA)(H O) ] n polymer is not well interpreted, but its µef f value shows that it is diamagnetic as expected Magnetic moments µef f of coordination polymers reveal that all the polymers except Zn(II) metal ion polymer are paramagnetic while Zn(II) metal ion polymer is diamagnetic The thermal behavior was investigated by PerkinElmer TGA analyzer at a heating rate of 10 ◦ C −1 in the temperature range 50–700 ◦ C under nitrogen, which provides much information about the coordination compounds In all the coordination polymers, decomposition occurred in steps (Figure 3) The first step, between 100 and 200 ◦ C, might be attributed to mass loss corresponding to water molecules The weight loss indicated that water molecules were coordinated to the metal ion The second step, between 200 and 700 ◦ C with the inflation at 350 ◦ C, exhibits a mass loss corresponding to decomposition of metal from the ligand part in the polymer The weight loss observed in the range of 11%–13% is consistent with metal degradation The major weight loss of the coordination polymers was noticeable beyond 400 ◦ C The rate of degradation became maximal at a temperature between 400 and 600 ◦ C This might be due to accelerating by metal oxide that formed in situ Each polymer lost about 80% of its weight when heated up to 700 ◦ C On the basis of the relative decomposition (% weight loss) and the nature of thermogram, the coordination polymers might be arranged in order of their increasing stability as follows: Cu < Fe < Ni < Co < Zn < Mn 3.3 Biological activity Antibacterial activity of BFMTA and its coordination polymers (Table 3) was tested against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and gram-negative bacteria (E coli and Salmonella typhi ) at a concentration of 50 µ g/mL by agar cup plate method A DMSO system was used as control in this method The area of inhibition was measured in millimeters The fungicidal activity of all the compounds was studied at 1000 ppm concentration in vitro The plant pathogenic organisms used were Penicillium expansum, Botrydepladia thiobromine, Nigrospora sp., and Trichothesium sp The antifungal activity of BFMTA and its coordination polymers was measured on each of these plant pathogenic strains on a potato dextrose agar (PDA) medium Such a PDA medium contains potato 200 g, dextrose 20 g, agar 20 g, and water L Five-day-old cultures were used The compounds to be tested were suspended (1000 ppm) in a PDA medium and autoclaved at 120 ◦ C for 15 at 15 atm pressure These media were poured into sterile petri plates and the organisms 984 PATEL et al./Turk J Chem were inoculated after cooling the petri plates The percentage inhibition for fungi was calculated after days using the formula given below: Percentage of inhibition = 100 (X – Y) / X where X = area of colony in control plate Y = area of colony in test plate 110 BFMTA [Mn(BFMTA)H2O)2]n [Fe(BFMTA)H2O)2]n [Co(BFMTA)(H2O)2]n [Ni(BFMTA)(H2O)2]n [Cu(BFMTA)(H2O)2]n [Zn(BFMTA)(H2O)2]n 100 90 80 % Weight loss 70 60 50 40 30 20 10 100 200 300 400 500 Temperature 600 700 Figure Thermogram of BFMTA and its coordination polymers Table Antibacterial and antifungal activity of the ligand and its polymers Compound BFMTA [Mn(BFMTA)(H2 O)2 ]n [Fe(BFMTA)(H2 O)2 ]n [Co(BFMTA)(H2 O)2 ]n [Ni(BFMTA)(H2 O)2 ]n [Cu(BFMTA)(H2 O)2 ]n [Zn(BFMTA)(H2 O)2 ]n Ciprofloxacin Antibacterial activity Zone of inhibition Gram +ve Gram –ve BS SA ST EC 22 20 21 23 27 30 27 30 32 33 35 35 27 25 26 30 29 27 28 29 34 33 36 39 32 31 30 31 43 42 45 47 Antifungal activity Zone of inhibition PE BT NS TS 26 31 37 32 25 39 30 46 22 26 30 25 26 32 28 39 23 30 34 28 28 36 28 48 20 25 32 28 25 35 24 41 BS: Bacillus subtilis, SA: Staphylococcus aureus, ST: Salmonella typhi, EC: Escherichia coli, PE: Penicillium expansum, BT: Botrydepladia thiobromine, NS: Nigrospora sp., TS : Trichothesium sp The levels of antibacterial and antifungal activity were compared with those of the standard drug ciprofloxacin As compared to ciprofloxacin, the compounds were less active The ligand was found biologically active, and its polychelates showed significantly enhanced biological activity compared to the ligand Among the coordination polymers, Fe(II) and Cu(II) coordination polymers showed better activity against all grampositive and gram-negative bacteria They also showed better activity against the plant pathogenic strain This might be due to the additive biological effect of parent molecule and/or the metal chelating properties of Fe(II) and Cu(II) 985 PATEL et al./Turk J Chem Conclusions A new ligand and its coordination polymers were prepared in good amount of yield and were duly characterized In the coordination polymers the ligand coordinates with central metal atom at coordination sites along with water molecules The structures of the ligand and its coordination polymers are consistent with the elemental, spectral, and thermal analyses The geometry of the central metal ion was confirmed by electronic spectra and magnetic susceptibility measurements All the data provide good evidence that the chelates are polymeric in nature These polymers not melt up to 400 ◦ C The polymers have moderate thermal stability and show good biological activity Acknowledgments One of the authors, Yogesh S Patel, is greatly thankful to the UGC for sanctioning his Teacher Fellowship under the scheme of the Faculty Improvement Programme for the research work References Dave, P N.; Patel, N N Mater Sci Appl 2011, 2, 771–776 Tamaki, R.; Choi, J.; Laine, R M Chem Mater 2003, 15, 793–797 Ueda, M.; Nakayama, T Macromolecules 1996, 29, 6427–6431 Yan, L.; Park, C.; Ounaies, Z.; Irene, E A Polymer 2006, 47, 2822–2829 Ramkumar, S G.; Ramakrishnan, S J Chem Sci 2008, 120, 187–194 Masahiro, T.; Takahiro, H.; Hiroyuki, O Tetrahedron Lett 2007, 48, 1553–1557 Matsuura, T.; Hasuda, Y.; Nishi, S.; Yamada, N Macromolecules 1991, 24, 5001–5005 Patel, Y S.; Patel, H S.; Srinivasulu, B Int J Plast Technol 2012, 16, 117–124 Patel, Y S.; Patel, H S Elixir Appl Chem 2012, 44, 7238–7242 10 Vanparia, S F.; Patel, T S.; Sojitra, N A.; 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Coordination Chemistry Interscience: New York, p 290, 1960 21 Papplardo, R J Chem Phys 1960, 33, 613–614 986 ... 400 500 Temperature 600 700 Figure Thermogram of BFMTA and its coordination polymers Table Antibacterial and antifungal activity of the ligand and its polymers Compound BFMTA [Mn(BFMTA)(H2 O)2 ]n... active, and its polychelates showed significantly enhanced biological activity compared to the ligand Among the coordination polymers, Fe(II) and Cu(II) coordination polymers showed better activity. .. Mn 3.3 Biological activity Antibacterial activity of BFMTA and its coordination polymers (Table 3) was tested against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and gram-negative