Synthetic, spectroscopic and thermal aspects of some heterochelates

• 2H 2 O was determined. Magnetic moment and reflectance spectral studies revealed that an octahedral geometry could be assigned to all the prepared heterochelates. Ligands (H 2 A n ) and their heterochelates were screened for their in-vitro antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Serratia marcescens bacterial strains. The kinetic parameters such as order of reaction (n), the energy of activation (E a ), the pre-exponential factor (A), the activation entropy ( S # ), the activation enthalpy ( H # ) and the free energy of activation ( G # ) are reported.

Section: Resultssupporting

confidence: 70%

“…The ν

_{as(COO^{−})}

and ν

_{s(COO^{−})}

vibrational frequencies, together with the ν

_{(COO^{−})}

Section: Resultsmentioning

confidence: 99%

Novel drug‐based Fe(III) heterochelates: synthetic, spectroscopic, thermal and in‐vitro antibacterial significance

Jani

Patel

Keharia

et al. 2009

“…According to the kinetic data obtained from DTG curves, all the heterochelates have negative entropy and indicates more ordered systems for the studied heterochelates51 The energy of activation ( E a ) is helpful in assigning the strength of the bonding of ligand moieties with the metal ion. The relatively high E a value (Table 4) indicates strong bonding between the metal ion and the ligand 52, 53. Thermoanalytical and thermodynamic data of heterochelates are reported in Tables 3 and 4 respectively.…”

Section: Resultsmentioning

confidence: 99%

Antibacterial, spectral and thermal aspects of some novel first transition metal‐based heterochelates

Oza

Jani

Patel

2010

1 H NMR, 13 C NMR and IR spectroscopic techniques and reacted with transition metal salts to afford metalcontaining heterochelates. The structures of the synthesized heterochelates were characterized using elemental analyses, infrared spectra, electronic spectra, magnetic measurements, FAB mass spectrum and thermogravimetric analyses. The kinetic parameters such as order of reaction (n) and the energy of activation (E a ) are reported using the Freeman-Carroll method. The pre-exponential factor (A), the activation entropy ( S # ), the activation enthalpy ( H # ) and the free energy of activation ( G # ) were calculated. Heterochelates were also screened for their in vitro antibacterial activity against a range of Gram-positive (Bacillus substilis, Staphylococcus aureus) and Gram-negative (Escherichia coli, Serratiamarcescens) organisms.

“…The final step involves complete ligand pyrolysis leaving free metallic residue. [73][74][75][76][77] The TG curves of complexes (2) and (3) show four decomposition steps within temperature ranges 20-220 C, 195-304 C, 290-500 C, and 395-1,000 C (Scheme 3). The first step is accompanied with estimated mass losses of 7.11% and 7.30%, respectively, attributable to complete desolvation with DTG peaks at 120 C and 167 C. After that, the decomposition of the complexes started at 220 C and 195 C, respectively, in the second step with DTG peaks at 400 C and 385 C associated with mass loses of 24.94% and 22.69%, respectively, assignable to the removal of coordinated chloride ion as well as partial ligand pyrolysis ( C 5 H 3 N) in addition to the loss of coordinated water complex 2 (Table 4).…”

Section: Thermal Studiesmentioning

confidence: 99%

Synthesis, spectral characterization, density functional theory studies, and biological screening of some transition metal complexes of a novel hydrazide–hydrazone ligand of isonicotinic acid

Tolan

Kashar

Yoshizawa

et al. 2021