Quantum chemical and experimental studies on the structure and vibrational spectra of efavirenz

Efavirenz, (S)-6-chloro-4(cyclopropylethynyl)-1, 4-dihydro-4-(trifluoromethyl)-2H-3,1-benzoxazin-2-one, is a anti HIV agent belonging to the class of the non-nucleoside inhibitors of the HIV-1 virus reverse transcriptase. Structural and spectral characteristics of efavirenz have been studied by methods of Raman spectroscopy and quantum chemistry. The optimized geometries, electronic charge distribution, dipole moments and electrostatic potential surface were calculated by Hartree–Fock and Density functional B3LYP method with the 6-311++G(d,p) basis sets. Electrostatic potential surfaces have been mapped over the electron density isosurfaces to obtain information about the size, shape, charge density distribution and chemical reactivity of the molecules.