Descriptors, Structural and spectroscopic Properties of Heterocyclic derivatives of importance for the health and the enviroment

MARÍA F. LADETTO; FLORENCIA C. CARO; ROXANA A. RUDYK; MARÍA A. CHECA; SILVIA A. BRANDÁN

Descriptors, Structural and spectroscopic Properties of Heterocyclic derivatives of importance for the health and the enviroment

NOVA Science Publishers, Inc.

Año: 2015; p. 201 - 218

In this chapter, a theoretical and comparative study of two sulfonylureas derivatives, the 2-(4,5-Dihydro-5-thioxo-1,3,4-oxadiazol-2-yl) benzenesulfonamide 2-(4,5- Dihydro-5-thioxo-1,3,4-oxadizol-2 -yl) benzenesulfonamide compounds is presented because both species are used largely as herbicides due to their low toxicity and because they are benign from te environmental point of view. Frist, the potential energy surfaces for both derivatives were studied in order to find the more stable conformers of each derivates. Thus, the three conformers most stable of each derivates were optimized in gas phase by using theorical calculations based in the density functional theory (DFT) and employing the 6-31G* basis set. Then, the results were used to compute some structural properties such as, atomic charges, bond orders, molecular electrostatic potential, stabilization energies and the HOMO-LUMO frontier orbitals. Later, their reactivities were predicted and evaluated by using the energy band gaps and some descriptors such as, chemical potential, electronegativity, global hardness, global softness and global electrophilicity index at the same level of theory. In addition, the different interactions for each conformer of both derivatives were evaluated by means of the topological properties using the atoms in molecules theory (AIM). Here, the properties for all the conformers of both derivatives were analyzed and compared between them.