||Theoretical Study of the Coordination of Semicarbazone and Its Methylated Derivatives
KUEVI URBAIN AMAH ,
KPOTIN ASSONGBA GASTON ,
ATOHOUN YACOLÈ GUY SYLVAIN ,
MENSAH JEAN-BAPTISTE ,
||International Journal of Chemistry
||Semicarbazone is a molecule with a group R1R2C=N-NR3-C(=O)-NR4R5.
The oxygen atom has two free electron pairs; each nitrogen atom has one free electron pair. These free electron pairs are
potential sites of coordination. The simplest molecule in this series is the semicarbazone which the formula is
H2C=N-NH-C(=O)NH2. By replacing the oxygen atom by a sulfur atom is obtained a thiosemicarbazone. Some
semicarbazones, such as nitrofurazone, and some thiosemicarbazones are known to have many properties: antiviral,
antibacterial, antitrypanosomal, anticonvulsant, antitumor, anticancer. They are usually mediated by an association with
copper or iron.
Indeed transition metal complexes with given chemical structures are useful alternatives in the treatment of certain
diseases since coordination of active ingredients deeply modifies both the physiological properties of metals and ligands
in the meaning of overall improvement of these properties.
The present work focuses on quantum study of the complexation of semicarbazone and its methylated derivatives. The
purpose of this study is to determine the most favorable coordination site of each of these ligands. It was found that the
oxygen atom appears more favorable to the coordination of semicarbazones.
Complexes of these ligands with the Zn (II) were modeled. The calculations were made by the method DFT / B3LYP
with the orbital basis 6-31G (d, p).
||coordination compounds, semicarbazones, DFT/ B3LYP, 6-31G (d,p) basis set
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