Quantum Computational and Spectroscopic Investigation (UV), MEP, HOMO-LUMO, Pharmacokinetic Studies of Meloxicam: A DFT Study

Our work describes the quantum chemical computational and UV-Vis investigation on 4-hydroxy-2-methyl-N-(5-methyl-2-thiazolyl)-2H-1, 2-benzothiazine-3-carboxamide-1,1-dioxide (meloxicam), a drug used to treat arthritis, a chronic disease. It is a non-steroidal anti-inflammatory drug (NSAID) that reduces pain, inflammation, fever, etc. This is a benzothiazine that is piroxicam in which the pyridine-2-yl group is repositioned by a 5-methyl-1, 3-thiazol-2-yl group. Its molecular formula is C14H13N3O4S2. The theoretical FT-IR wave numbers and UV analysis were obtained using Gaussian 09 software with B3LYP 6-311++G (d, p) as the basis set. The extensive vibrational summaries are given with the help of VEDA software using potential energy distribution (PED). Along with this, HOMO-lowest occupied molecular orbital (LUMO) energy gap determines the chemical hardness and softness of the molecule, which in turn gives the chemical and kinetic stability of the molecule. NLO, molecular electrostatic potential (MEP) studies are also done in parallel which as a whole gives the total analysis of the title molecule.