scholarly journals Synthetic, structural and biological studies of organosilicon(IV) complexes of Schiff bases derived from pyrrole-2-carboxaldehyde

2010 ◽  
Vol 75 (7) ◽  
pp. 917-927 ◽  
Author(s):  
Kiran Singh ◽  
Dharam Pal

Selected new organosilicon(IV) complexes having the general formula R2SiCl[L] and R2Si[L]2 were synthesized by the reactions of Me2SiCl2 with Schiff bases [5-mercapto-4-(2-pyrrolecarboxalideneamino)-s-triazole, 5-mercapto-3-methyl-4-(2-pyrrolecarboxalidene amino)-s-triazole and 3-ethyl-5-mercapto-4-(2-pyrrolecarboxalideneamino)-s-triazole] in 1:1 and 1:2 molar ratios. All of the compounds were characterized by elemental analysis, molar conductance, and IR, UV, 1H-, 13C- and metal-NMR spectral studies. All the spectral data suggest an involvement with an azomethine nitrogen in coordination to the central metal atom. With the help of above-mentioned spectral studies, penta and hexacoordinated environments around the central metal atoms in the 1:1 and 1:2 complexes, respectively, are proposed. Finally, the free ligands and their metal complexes were tested in vitro against some pathogenic bacteria and fungi to assess their antimicrobial properties.

2007 ◽  
Vol 2007 ◽  
pp. 1-7 ◽  
Author(s):  
Sulekh Chandra ◽  
Smriti Raizada ◽  
Monika Tyagi ◽  
Archana Gautam

A series of metal complexes of Cu(II) and Ni(II) having the general composition[M(L)X2]with benzil bis(thiosemicarbazone) has been prepared and characterized by element chemical analysis, molar conductance, magnetic susceptibility measurements, and spectral (electronic, IR, EPR, mass) studies. The IR spectral data suggest the involvement of sulphur and azomethane nitrogen in coordination to the central metal ion. On the basis of spectral studies, an octahedral geometry has been assigned for Ni(II) complexes but a tetragonal geometry for Cu(II) complexes. The free ligand and its metal complexes have been tested in vitro against a number of microorganisms in order to assess their antimicrobial properties.


2009 ◽  
Vol 2009 ◽  
pp. 1-6 ◽  
Author(s):  
Sulekh Chandra ◽  
Shikha Parmar ◽  
Yatendra Kumar

A series of metal complexes of Zn(II) and Hg(II) having the general composition [where L = 2-formylpyridine thiosemicarbazone; M = Zn(II) and Hg(II); X = , and ] have been prepared and characterized by elemental chemical analysis, molar conductance, and spectral (IR and mass) studies. The IR spectral data suggests the involvement of sulphur and azomethane nitrogen in coordination to the central metal ion. On the basis of spectral studies, a tetrahedral geometry has been assigned for Zn(II) and Hg(II) complexes. The free ligand and its metal complexes have been tested in vitro against a number of microorganisms in order to assess their antimicrobial properties.


2002 ◽  
Vol 8 (6) ◽  
pp. 347-353 ◽  
Author(s):  
Ashu Chaudhary ◽  
D. P. Jaroli ◽  
R. V. Singh

Some antifertility inhibitors of 18 to 24-membered tetraazamacrocyclic complexes of iron(II) and manganese(II) have been synthesised by the template condensation using 1,3-phenylenediamine with malonic acid, succinic acid, glutaric acid and adipic acid. The reaction proceed smoothly to completion. The complexes were characterized by elemental analyses, molecular weight determinations, infrared, electronic, magnetic moment, mössbaur and mass spectral studies. The elemental analyses are consistent with the formation of the complexes [M(N4Ln)Cl2] (M = Fe(lI) or Mn(II)). All these complexes are stable and monomeric in nature as indicated by the molecular weight determinations. The spectral studies confirm the octahedral geometry around the central metal atom. The complexes have been screened in vitro against a number of fungi and bacteria to assess their growth inhibiting potential. The testicular sperm density and testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trials and biochemical parameters of reproductive organs have been examined and discussed.


2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Har Lal Singh ◽  
Jangbhadur Singh

New series of organotin(IV) complexes and Schiff bases derived from amino acids have been designed and synthesized from condensation of1H-indole-2,3-dione, 5-chloro-1H-indole-2,3-dione, andα-amino acids (phenylalanine, isoleucine, and glycine). All compounds are characterized by elemental analyses, molar conductance measurements, and molecular weight determinations. Bonding of these complexes is discussed in terms of their UV-visible, infrared, and nuclear magnetic resonance (1H,13C, and119Sn NMR) spectral studies. The results suggest that Schiff bases behave as monobasic bidentate ligands and coordinate with dibutyltin(IV) in octahedral geometry according to the general formula [Bu2Sn(L)2]. Elemental analyses and NMR spectral data of the ligands with their dibutyltin(IV) complexes agree with their proposed distorted octahedral structures. Few representative compounds are tested for their in vitro antibacterial activity against Gram-positive (B. cereus,Staphylococcusspp.) and Gram-negative (E. coli,Klebsiellaspp.) bacteria. The results show that the dibutyltin complexes are more reactive with respect to their corresponding Schiff base ligands.


Author(s):  
Mallikarjun S. Yadawe ◽  
Shrishila N. Unki ◽  
Sangamesh A. Patil

Some lanthanum(III) complexes have been synthesized by reacting lanthanum(III) metal salt with Schiff bases derived from 3-substituted-4-amino-5-mercapto-1,2,4-triazole and glyoxal/biacetyl/benzyl. All these complexes are not soluble in common organic solvents. However sparingly soluble in DMF and DMSO. The chemical analysis of the complexes confirmed to the stoichiometry of the type La(III)LNO3·H2O. La(III)LCl·H2O and La(III)LNCS·H2O respectively. The chelation of the complexes has been proposed in the light of analytical, spectral studies. The measured molar conductance values indicate that, the complexes are non-electrolytes. The Schiff bases and their complexes have been screened for their antibacterial and antifungal activities. The results of these studies show the metal complexes to be more antibacterial and antifungal as compared to the uncomplexed coumarins.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Kiran Singh ◽  
Parvesh Puri ◽  
Yogender Kumar ◽  
Chetan Sharma

This paper deals with the syntheses and structural features of some new diorganosilicon(IV) and diorganotin(IV) complexes having general formulae (CH3)2MCl(L1), (CH3)2MCl(L2), (CH3)2M(L1)2, and (CH3)2M(L2)2 with new Schiff bases (M = Si and Sn). The Schiff bases HL1 and HL2 have been derived from the condensation of 3-bromobenzaldehyde with 4-amino-3-ethyl-5-mercapto-1,2,4-triazole and 4-amino-5-mercapto-3-propyl-1,2,4-triazole, respectively. The compounds have been characterized by the elemental analyses, molar conductance, and spectral (UV, IR, 1H, 13C, 29Si, and 119Sn NMR) studies. The resulting complexes have been proposed to have trigonal bipyramidal and octahedral geometries. In vitro antimicrobial activities of the compounds have been carried out.


2009 ◽  
Vol 63 (5) ◽  
Author(s):  
Ajay Mishra ◽  
Shivani Mishra ◽  
Narender Kaushik

AbstractSynthesis, characterization and biological studies of some thiodiamine metal complexes are described. Cobalt(II) and copper(II) complexes of type [Cu(L)2Cl2] and [Co(L)2SO4], where L = (cyclohexyl-N-thio)-1,2-ethylenediamine (L1) and (cyclohexyl-N-thio)-1,3-propanediamine (L2), were synthesized. The synthesized copper and cobalt thiodiamine complexes were characterized by elemental analysis, IR, mass, UV-VIS and 1H NMR spectroscopic studies. Thiodiamines coordinate as a bidentate N-S ligand. The binding sites are azomethine nitrogen and thioamide sulfur. Molar conductance values in dimethylsulfoxide indicate non-electrolyte nature of the complexes. In vitro-antimicrobial screening shows promising results against both bacterial and fungal strains.


2019 ◽  
Vol 7 (1) ◽  
pp. 9-15
Author(s):  
Hamid Beyzaei ◽  
Hadis Hosseini Moghadam ◽  
Ghodsieh Bagherzade ◽  
Reza Aryan ◽  
Mohammadreza Moghaddam-Manesh

Background: Design, identification, and synthesis of new antimicrobial agents along with preventive proceedings are essential to confront antibiotic-resistant pathogenic bacteria. Heterocyclic Schiff bases are biologically important compounds whose antimicrobial potentials have been proven to bacterial and fungal pathogens. Objectives: In this study, some quinoline Schiff bases were synthesized from condensation of 2-chloro3-quinolinecarboxaldehyde and aniline derivatives. Their inhibitory activities were evaluated against 6 gram-positive and 2 gram-negative bacterial pathogens. Methods: Disc diffusion, broth microdilution, and time-kill tests were applied according to the CLSI guidelines to determine IZD, MIC, and MBC values. Results: 2-Chloro-3-quinolinecarboxaldehyde Schiff bases could inhibit the growth of bacteria with IZDs of 7.5-19.8 mm, MICs of 256-2048 μg mL-1, and MBCs of 512 to ≥2048 μg mL-1. Conclusion: Moderate antibacterial effects were observed with heterocyclic Schiff bases. Complexation and structural changes can improve their antimicrobial properties.


2015 ◽  
Vol 12 (2) ◽  
pp. 350-361 ◽  
Author(s):  
Baghdad Science Journal

A new series of metal ions complexes of VO(II), Cr(III), Mn(II), Zn(II), Cd(II) and Ce(III) have been synthesized from the Schiff bases (4-chlorobenzylidene)-urea amine (L1) and (4-bromobenzylidene)-urea amine (L2). Structural features were obtained from their elemental microanalyses, magnetic susceptibility, molar conductance, FT-IR, UV–Vis, LC-Mass and 1HNMR spectral studies. The UV–Vis, magnetic susceptibility and molar conductance data of the complexes suggest a tetrahedral geometry around the central metal ion except, VOII complexes that has square pyramidal geometry, but CrIII and CeIII octahedral geometry. The biological activity for the ligand (L1) and its Vanadium and Cadmium complexes were studied. Structural geometries of compounds also were suggested in gas phase by using theoretical treatments, using Hyper Chem-6 program for the molecular mechanics and semi-empirical calculations. The heat of formation (?Hf ?) and binding energy (?Eb) in the temperature of 298K for the free ligand (L1) and their metal complexes were calculated by PM3 and ZINDO/I methods. The electrostatic potential of the free ligands were calculated to investigate the reactive sites of the molecules.Bacteriological evaluation of considerable number of these compounds were maintained using organisms Escherichia coli and Staphylococcus aureus,and they were found to exhibit the high effect of activity. This may be attributed to the impact of both the Schiff bases and the metal present in these complexes.


2013 ◽  
Vol 2 (4) ◽  
pp. 88-91 ◽  
Author(s):  
Sandeep Kumar ◽  
Nitin Kumar

In present work, Ligand acetylacetone thiosemicarbazone and their 11 complexes of the type ML2X2, ML2X’, where M = Cu(II), Cd(II), Co(II), Zn(II), Hg(II); L = acetylacetone thiosemicarbazone; X = Cl, NO3 or CH3COO; X’ = SO4 have been synthesized and characterized with the help of molar conductance, magnetic susceptibility measurements, infra-red and ultra-violet spectroscopy. The spectral data revealed that the thiosemicarbazone act as bidentate ligand, making use of thionic sulphur and the azomethine nitrogen atom for co-ordination to the central metal atom. All the compounds have been screened for their antibacterial activity against Gram positive bacteria Staphylococcus aureus, Staphylococcus epidermidis and Gram negative bacteria Escherichia coli and Pseudomonas aeruginosa. Some of complexes exhibited appreciable activity.DOI: http://dx.doi.org/10.3329/icpj.v2i4.14057 International Current Pharmaceutical Journal, March 2013, 2(4): 88-91


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