title: Synthesis, pharmacological screening, quantum chemical and in vitro permeability studies of N-Mannich bases of benzimidazoles through bovine cornea.
abstract: A novel series of N-Mannich bases of benzimidazole derivatives were synthesized and characterized by (1)H NMR, IR spectral studies and elemental analysis. The compounds were screened for analgesic and anti-inflammatory activity. 1-((Diethylamino)-methyl)-2-styryl benzimidazole 4 at 40mg/kg was found to be equipotent to paracetamol. 1-((Piperidin-1-yl) methyl)-2-styryl-benzimidazole 6 at 40mg/kg was found to be more potent than Diclofenac. Corneal permeability and quantum chemical calculations were performed to correlate the hydrogen bonding ability with permeability and activity. The energies of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) were correlated with pharmacological activity. The semi-empirical PM3 calculations (quantum chemical calculations) revealed that E(LUMO) and energy gap DeltaE were capable of accounting for the high in vitro bovine corneal permeability and activity of the compounds.
authors.affiliation: Bio-Organic and Neurochemistry Laboratory, Central Leather Research Institute, Sardar Patel Road, Adyar, Chennai 600020, Tamil Nadu, India.
authors.forename: E Philip
authors.initials: EP
authors.lastname: Jesudason
authors.forename: S K
authors.initials: SK
authors.lastname: Sridhar
authors.forename: E J Padma
authors.initials: EJ
authors.lastname: Malar
authors.forename: P
authors.initials: P
authors.lastname: Shanmugapandiyan
authors.forename: Mohammed
authors.initials: M
authors.lastname: Inayathullah
authors.forename: V
authors.initials: V
authors.lastname: Arul
authors.forename: D
authors.initials: D
authors.lastname: Selvaraj
authors.forename: R
authors.initials: R
authors.lastname: Jayakumar
mesh_terms: D000700:Analgesics / Q000138:chemical synthesis / Q000493:pharmacokinetics; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000138:chemical synthesis / Q000493:pharmacokinetics; D001562:Benzimidazoles / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D002417:Cattle; D002463:Cell Membrane Permeability; D003315:Cornea / Q000378:metabolism*; D004353:Drug Evaluation, Preclinical; D006860:Hydrogen Bonding; D008352:Mannich Bases / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D008958:Models, Molecular
chemical_list: D000700:Analgesics; D000893:Anti-Inflammatory Agents; D001562:Benzimidazoles; D008352:Mannich Bases