Spectral characterization,antimicrobial and antibiofilm activity of poly(propylene imine) metallodendrimers in solution and applied onto cotton fabric

Abstract

Poly(propylene imine) dendrimers from first and third generation modified with 1,8-naphthalimide units and their Cu(II) complexes have been characterized by fluorescence and EPR spectroscopy. Cotton fabric has been modified with these dendrimers and their color characteristics were determined. The antimicrobial activity of dendrimer ligands and their Cu(II) complexes in solution and after their deposition on a cotton fabric was investigated. Good antibacterial effect of dendrimer ligands has been obtained, which is enhanced at their Cu(II) complexes. After their deposition on cotton fabric metallodendrimers exhibit good antibiofilm activity.     

Sensor activity, photodegradation and photostabilisation of a PAMAM dendrimer comprising 1,8-naphthalimide functional groups in its periphery

The colouristic and fluorescent characteristics of a new composite material based on a PAMAM dendrimer of second generation whose periphery is modified with 4-N,N-dimethylaminoethylamino-1,8-naphthalimide and polyamide-6 have been investigated. This dendrimer has been investigated with regard to its application as a heterogenic sensor capable of detecting metal cations and protons in aqueous solutions. In the presence of metal cations (Ni²⁺, Fe²⁺, Fe³⁺ and Co²⁺) and protons the fluorescence intensity of the composite increases due to their coordination with dendrimer molecule. The results obtained reveal the capacity of this system to act as a sensitive sensor of environmental pollution by metal cations and protons. It has been shown that in N,N-dimethylformamide solution the metal cations inhibit the processes of photodegradation of the dendrimer.     

Synthesis,characterization, and antimicrobial activity of new benzoylthiourea ligands

In this study, new benzoylthiourea derivatives, (E)-N-[(2-benzamidomethyleneamino)ethylcarbamothioyl]benzamide H₃L′, N-(1-(3-benzoylthioureido)propan-2-ylcarbamothioyl)-benzamide H₄L″, (E)-N-[4-(benzamidomethyleneamino)phenylcarbamothioyl]benzamide H₃L‴, were synthesized. Structures of the compounds were identified by spectroscopic techniques. In addition, all synthesized compounds were evaluated for in vitro antibacterial and antifungal activity. Compound H₃L‴ exhibited antibacterial activity.     

Synthesis, characterization and antimicrobial activity of new 1,2,3-selenadiazoles

The commercially available aromatic polyketones 1a-d were utilized for the synthesis of the multi-arm1,2,3-selenadiazole derivatives 3a-d. The preparation starts with the reaction between compounds 1a-d and p-toluenesulfonyl hydrazide to give the corresponding tosylhydrazones 2a-d. Subsequent reaction with selenium dioxide leads to regiospecific ring closure of the tosylhydrazones to give the target multi-arm 1,2,3-selenadiazole derivatives in high yield. A 1,2,3-selenadiazole derivative 3e containing an epoxide ring was also prepared. The structures of all the synthesized compounds were confirmed on the basis of spectral and analytical data. The compounds were screened in vitro for their antimicrobial activity against various pathogenic bacterial and Candida strains obtained from King Abdullah Hospital in Irbid -Jordan. Compounds 3a, 3c and 3e were found to be highly active against all the selected pathogens. Compound 3e showed an inhibition zone of 13 mm against the highly resistant P. aruginosa.     

Synthesis,characterization, and antimicrobial activity of new benzofuran derivatives

Russian Journal of General Chemistry - A novel series of (5-substituted-1-benzofuran-2-yl)(2,4-substituted phenyl)methanones (4a–4i) have been prepared by the Knoevenagel condensation of...     

Synthesis and in vitro antimicrobial studies of thiodihydropyrimidine derivatives

In the present study, a series of thiodihydropyrimidine derivatives were synthesized from different substituted aromatic aldehydes, ethyl acetoacetate, and urea/thiourea using a bimetallic TUD-1 catalyst. The structures of all the synthesized compounds were characterized by melting point determination, thin layer chromatography (TLC), infrared (IR), ¹HNMR, and ¹³C-NMR values. All the synthesized compounds were screened for their antimicrobial activities against two gram positive bacteria, two-gram negative bacteria, and two fungal strains.     

Synthesis,characterization and antimicrobial activity of a new macrocycle and its transition metal complexes

The semicarbazone (L¹) has been prepared by reaction of semicarbazide and glutaraldehyde (2 : 1) in distilled water and methanol (1 : 1). The reaction of semicarbazide, glutaraldehyde and diethyl oxalate in distilled water and methanol gave Schiff-base L², 1,2,4,7,9,10-hexaazacyclo-pentadeca-10,15-dien-3,5,6,8-tetraone. Complexes of first row transition metal ions Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) have also been synthesized. The ligand and its complexes were characterized by elemental analysis, molar conductance, magnetic moment measurements, IR, ¹H NMR, UV–Visible spectra and thermogravimetric analysis (TGA). Molar conductance values show that the complexes of Ni(II), Cu(II), Zn(II), Mn(II) and Co(II) are 1 : 2 electrolytes. On the basis of electronic spectral studies and molar conductance measurements an octahedral structure has been proposed for Mn(II) and Co(II) complexes, tetrahedral for Zn(II) complex and square planar for Ni(II) and Cu(II). The thermal behavior of the compounds, studied by TGA in a nitrogen atmosphere up to 800°C, reveal that the complexes have higher thermal stability than the macrocycle. All the synthesized compounds and standard drugs kanamycin (antibacterial) and miconazole (antifungal) have been screened against bacterial strains Staphylococcus areus, Escherichia coli and fungal strains Candida albicans, Aspergillus niger. The metal complexes inhibit growth of bacteria to a greater extent than the ligand.     

Synthesis,characterization and antimicrobial activity of some new biquinoline derivatives containing a thiazole moiety

A series of new biquinoline derivatives containing a thiazole moiety were synthesized by a one-pot,base-catalyzed cyclocondensation reaction of 2-chloro-3-formyl quinoline,malononitrile and enaminone.All the synthesized compounds were characterized by elemental analysis,FT-IR,¹H NMR and ¹³C NMR data.All the synthesized compounds were screened against three bacterial pathogens,namely Bacillus cereus,B.substilis and Escherichia coli and for antifungal activity against three fungal pathogens,Aspergillus niger,Fusarium oxisporum and Rhizopus using the disc diffusion method.     

Synthesis,spectroscopic characterization and in vitro studies of antimicrobial activity of bis(diorganodithiocarbamato)organodithiocarbonatobismuth (III) complexes

A brief account of the synthesis, spectroscopic characterization and the antimicrobial (bacterial and fungal) behaviour of bis(diorganodithiocarbamato)organodithiocarbonatobismuth(III) complexes is presented. The reaction of bis(diorganodithiocarbamato)bismuth(III) chloride with potassium organodithiocarbonate in equimolar ratio yielded the corresponding mixed derivatives of the type [R′₂NCS₂]₂BiS₂COR [where, R′ = CH₃ and C₂H₅; R = Et, Prⁿ, Prⁱ, Buⁿ and Buⁱ]. These have been characterized by molecular weight determinations, melting points (only solid complexes) and elemental (C, H, N, S and Bi) analysis as well as spectral IR and NMR [¹H and ¹³C] studies. The antibacterial and antifungal activities of the free ligands and their bismuth complexes were found in vitro by the disc diffusion method. The complexes showed good antibacterial and antifungal effect on some selected bacterial and fungal strains. The antimicrobial activities of two standard antibiotics (Chloroamphenicol and Terbinafin) were also measured and compared with these complexes. Copyright © 2005 John Wiley & Sons, Ltd.     

Synthesis,characterization, and antimicrobial activity of new bis-1,2,3-triazol-H-yl-substituted 2-arylbenzimidazoles

New bis-1,2,3-triazol-H-yl-substituted 2-aryl benzimidazoles VIa-VIp were synthesized from O- and N-bis-propargyl substituted 2-arylbenzimidazoles using “click chemistry.” The newly synthesized compounds were characterized by IR, NMR, and mass spectra. These compounds were screened for their activity against bacterial and fungal organisms.     

Synthesis,antimicrobial activity and QSAR studies of 2,5-disubstituted benzoxazoles

In this study, a new series of 2,5-disubstituted benzoxazoles was synthesized and their structures were elucidated by elemental analysis, MASS, ¹H-NMR, ¹³C-NMR and IR spectral data. Newly and previously synthesized 2,5-disubstituted benzoxazole derivatives were evaluated for antibacterial and antifungal activity against standard strains and their drug-resistant isolates. Microbiological results showed that the compounds presented a large spectrum of activity having MIC values of 250–7.8 µg mL^?1 against the tested microorganisms. Among the newly synthesized derivatives 3–22, compound 11 was the most active against Candida krusei out of all; however, it was one dilution less potent than standard drug fluconazole. In addition, all the new and previous compounds were more active than standard drugs ampicillin trihydrate and rifampicin against Pseudomonas aeruginosa and its gentamicin-resistant isolate. The 2D-QSAR (Quantitative Structure–Activity Relationship) analysis of a set of newly and previously synthesized benzoxazoles tested for growth inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA) was also performed by using multivariable regression analysis. The activity contributions for substituent effects of these compounds were determined from the correlation equation for predictions of the lead optimization.     

Two new fluorescent heterocyclic perimidines: first syntheses, crystal structure, and spectral characterization

An efficient one-pot synthesis of two new heterocyclic perimidines 4-(2,3-dihydro-1H-perimidin-2-yl)-2-methoxyphenol and 2-(quinoxalin-2-yl)-2,3-dihydro-1H-perimidine in good yields is presented. This methodology provides a simple, straightforward synthetic route to these interesting classes of heterocycles. Crystal structure, solvatochromism, and antibacterial activity of these organic compounds are discussed.     

Synthesis,characterization and antimicrobial activity of zinc(II) ibuprofen complexes with nitrogen-based ligands

Metal carboxylate complexes possess different carboxylate coordination modes, e.g. monodentate, bidentate, and bridging bidentate. Five Zn(II) complexes were prepared and characterized in order to examine their coordination modes in addition to their biological activity. The syntheses were started by preparation of [Zn(ibup)₂(H₂O)₂] (1). Then, different nitrogen-donor ligands reacted with 1 to produce [Zn(ibup)₂(2-ampy)₂] (2), [Zn(ibup)(2-ammethylpy)] (3), [Zn(ibup)(2,2′-bipy)] (4), and [Zn₂(ibup)₄(2-methylampy)₂] (5) (ibup = ibuprofen, 2-ampy = 2-aminopyridine, 2-ammethylpy = 2-aminomethylpyridine, 2,2′-bipy = 2,2′-bipyridine, 2-methylampy = 2-(methylamino)pyridine). IR, ¹H NMR, ¹³C{¹H}-NMR and UV–vis spectroscopies were used for characterization. The crystal structures of 2 and 5 were determined by single-crystal X-ray diffraction. Investigation of in vitro antibacterial activities for the complexes against Gram-positive (Micrococcus luteus, Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis) bacteria were done using agar well-diffusion method. Complex 1 showed antibacterial activity against Gram-positive bacteria. Complexes 2 and 3 did not exhibit antibacterial activity. Complex 4 showed antibacterial activity and was chosen for further studies to determine the inhibition zone diameter for different concentrations and to set the minimum inhibitory concentration. The antibacterial activity against most of the bacteria was minimized as a result of the complexation of zinc ibuprofen with 2,2′-bipy in 4.     

Synthesis,spectral and antimicrobial activity studies of o-aminoacetophenone o-hydroxybenzoylhydrazone complexes

Coordination compounds of Mn^II, Co^II, Ni^II, Cu^II, Zn^II, Cd^II and Hg^II ions with o-aminoacetophenone o-hydroxybenzoylhydrazone (AAOHBH) were synthesized and characterized by elemental analyses, molar conductivity, magnetic moments (at ca. 25°C) and spectral (i.r., u.v., n.m.r. and m.s.) studies. The i.r. spectra show that the ligand acts in a monovalent bidentate, neutral bidentate and/or neutral tridentate fashion, depending on the metal salt used and the reaction medium. Tetrahedral structures are proposed for both Co^II and Ni^II complexes and square planar for Cu^II complexes on the basis of magnetic and spectral evidence. The complex formation in solution was investigated potentiometrically and spectrophotometrically. Spectral studies in solution show that the ligand can be used for the microdetermination of Co^II ion within a metal concentration up to 46.3p.p.m. The electrical conductivity of AAOHBH and its metal complexes was determined. The tendency of AAOHBH to form complexes with Co^II, Ni^II, Cu^II, Cd^II and Hg^II ions in 50% aqueous-dioxane was studied by pH measurements.The antimicrobiol activity of AAOHBH and its complexes derived from Co^II, Ni^II and Cu^II illustrates that the Ni^II complex seems to be inert towards Escherichia coli and Bacillus subtilis. The antimicrobial activity of the Cu^II complex was higher against E. coli and lower against B. subtilis than the corresponding organic ligand. The Co^II complex has the same activity as the organic ligand against E. coli.     

Synthesis, spectral characterization of Schiff base transition metal complexes: DNA cleavage and antimicrobial activity studies

A new series of transition metal complexes of Cu(II), Ni(II), Co(II), Mn(II), Zn(II), VO(IV), Hg(II) and Cd(II) have been synthesized from the Schiff base (L) derived from 4-aminoantipyrine, 3-hydroxy-4-nitrobenzaldehyde and o-phenylenediamine. Structural features were obtained from their elemental analyses, magnetic susceptibility, molar conductance, mass, IR, UV-Vis, ¹H NMR and ESR spectral studies. The data show that these complexes have composition of ML type. The UV-Vis, magnetic susceptibility and ESR spectral data of the complexes suggest a square-planar geometry around the central metal ion except VO(IV) complex which has square-pyramidal geometry. The redox behaviour of copper and vanadyl complexes was studied by cyclic voltammetry. Antimicrobial screening tests gave good results in the presence of metal ion in the ligand system. The nuclease activity of the above metal complexes shows that Cu, Ni and Co complexes cleave DNA through redox chemistry whereas other complexes are not effective.     

Synthesis,characterization and in vitro antimicrobial prospecting of silver-doped ceria

Journal of Thermal Analysis and Calorimetry - In this work, Ag-doped CeO2 samples containing 0.5 mol% Ag+ were successfully synthesized by the polymeric precursor method and then calcined...     

Synthesis,characterization, antimicrobial activity and ultrastructure of the affected bacteria of new quinoline compounds

The reaction on 8-hydroxy quinoline-7-aldehyde azo compounds (HL _n ) (where n = 1–5) with 4-amino-1,2-dihydro-2,3-dimethyl-1-phenylpyrazol-5-one to obtain HL _n (where n = 6–10) have been characterized by means of TLC, melting point and spectral data, such as IR, ¹H NMR, mass spectra and thermal studies. The X-ray diffraction patterns of two starting materials 8-hydroxy quinoline-7-aldehyde (start 1), 4-amino-1,2-dihydro-2,3-dimethyl-1-phenylpyrazol-5-one (start 2) and the ligands (HL_5,10) are investigated in powder form. All the ligands have been screened for their antimicrobial activity against four local bacterial species, two Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus) and two Gram-negative bacteria (Escherichia coli and Klebsiella pneumoniae) as well as against four local fungi; Aspergillus niger, Alternaria alternata, Penicillium italicum and Fusarium oxysporium. The results show that the azo ligands (HL _n ) (where n = 1–5) have no antimicrobial activity against bacteria and fungi while most azomethine ligands (HL _n ) (where n = 6–10) are good antibacterial agents against E. coli and K. pneumoniae as well as antifungal agents against P. italicum and A. alternata. The results were compared to standard substances (start 1) and (start 2). Among the azomethine ligands, HL₁₀ was the most effective against the most microorganisms tested. The size of clear zone was ordered as p-(OCH₃ < CH₃ < H < Cl < NO₂) as expected from Hammett’s constant (σ ^R ). Also, the ultrastructure study of the affected bacteria confirmed that HL₈ is good antibacterial agent against E. coli and S. aureus.     

Synthesis,characterization and antimicrobial activities of new bis-hydrazonothioxothiazolidinone derivatives

New bis-hydrazonothioxothiazolidinone derivatives based on 2-thioxothiazolidin-4-one were synthesized in good yields using a simplified experimental condition. The structure of synthesized compounds was established with the help of common physico-chemical analysis and various spectroscopic techniques like FT-IR, mass and ¹H NMR. The results of characterizations are in good agreement with the proposed structure of all the synthesized compounds. Further, the antimicrobial (antibacterial and antifungal) activities of all the synthesized derivatives were carried out against various species like Bacillus subtilis, Escherichia coli, Aspergillous niger and Aspergillous flavus by using agar-cup method. The results of antimicrobial screening showed that all the compounds have mild to moderate activity. However, some of the compounds (3a, 3b, 3d, 3e, 3f, 3g, 3i and 3j) have shown better activity than the other.     

Synthesis,spectral characterization,electrochemical properties and antimicrobial screening of sulfur containing acylferrocenes

Several known and eight new sulfur containing acylferrocenes of the general formula FcCO(CH₂)_nSR (where Fc = ferrocenyl, n = 1 or 2 and R = alkyl, 4-bromobenzyl or 2,6-dichlorobenzyl group) were synthesized in order to test their in vitro antimicrobial activity against 11 bacterial and three fungal/yeast strains. It has been shown that only four of the 14 ketones are completely inactive at the tested dose, while the activities of the other ones were noteworthy. All new compounds were well characterized by IR and NMR spectral data, and their electrochemical properties were investigated by cyclic voltammetry. The X-ray crystal structures of two representative ketones are also presented.     

Synthesis,characterization and liquid chromatographic behaviours of a new chemically bonded liquid crystal

A new bonded liquid crystal stationary phase (2OC12) for high-performance liquid chromatography was studied. It resulted from coupling of LiChrospher Si 100 NH2 and a mesogenic carboxylic acid, 4-(4-(4-(3,4-didoceyloxystyrenyl)phenyl-diazenyl)phenyloxy-methylene) benzoic acid (ILC). ILC was characterized with proton NMR and differential scanning calorimetry, while 2OC12 was characterized by solid state 13C NMR and elemental analysis. 2OC12 surface area was determined by the BET method. The chromatographic behaviour of 2OC12 was investigated under both normal- and reversed-phase conditions. The plots of ln k against 1/T showed transition temperatures at 325 and 337 K. Polyaromatic hydrocarbons (PAHs) were separated using hexane, isooctane or hexane-chloroform. Above the transition temperatures, the bonded material exhibited a liquid crystal-like behaviour: (i) the plate number N was always highest possible, and (ii) the more retained the solute the more elongated it was (anthracene is eluted after phenanthrene, chrysene before tetracene, pentacene after dibenzo-a,h-anthracene). Using acetonitrile/water (60/40), reversed-phase data of aromatic hydrocarbons are similar (highest values of N, better resolution below than during the transitions).