Vibrational spectroscopic (FT-IR and FT-Raman) studies, HOMO-LUMO, NBO analysis and MEP of 6-methyl-1-({[(2E)-2-methyl-3-phenyl-prop-2-en-1-yl]oxy}methyl)-1,2,3,4-tetra-hydroquinazoline-2,4-dione, a potential chemotherapeutic agent, using density functional methods.

6-Methyl-1-({[(2E)-2-methyl-3-phenyl-prop-2-en-1-yl]oxy}methyl)-1,2,3,4-tetra-hydro quinazoline-2,4-dione was prepared via treatment of silylated 6-methylquinazoline-2,4-dione with bis-[(E)-2-methyl-3-phenylallyloxy]methane. FT-IR and FT-Raman spectra were recorded and analyzed. The vibrational wavenumbers were computed using DFT methods and are assigned with the help of potential energy distribution method. The first hyperpolarizability, infrared intensities and Raman activities also reported. The geometrical parameters of the title compound obtained from XRD studies are in agreement with the calculated (B3LYP) values. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis are used to determine the charge transfer within the molecule. MEP was performed by the B3LYP method and from the MEP it is evident that the negative charge covers the CO group and the positive region is over the phenyl ring and NH group.

Vibrational spectroscopic studies (FT-IR, FT-Raman) and quantum chemical calculations on 5-(Adamantan-1-yl)-3-[(4-fluoroanilino)methyl]-2,3-dihydro-1,3,4-oxadiazole-2-thione, a potential chemotherapeutic agent.

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 5-(Adamantan-1-yl)-3-[(4-fluoroanilino)methyl]-2,3-dihydro-1,3,4-oxadiazole-2-thione are investigated experimentally and theoretically using Gaussian09 software package. Potential energy distribution of normal modes vibrations was done using GAR2PED program. The HOMO and LUMO analysis are used to determine the charge transfer within the molecule. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The calculated geometrical parameters are in agreement with the XRD data. The calculated first hyperpolarizability is high and the title compound is an attractive candidate for further studies in non-linear optical applications. To estimate the chemical reactivity of the molecule, the molecular electrostatic potential is calculated for the optimized geometry of the molecule.