Investigation of the structure and properties of some indazole derivatives using the AM1, PM3 and MNDO semiempirical methods.: 2.: An aqueous phase study

In this work the aqueous phase physicochemical properties of some 3-substituted indazole derivatives were computed by using semiempirical methods and the obtained results were evaluated by searching a possible correlation with the previously obtained experimental properties. The aqueous phase geometries, relative stabilities, acidity constants, tautomerism, proton affinities and dipole moments for the tautomeric forms of some 3-substituted indazoles and their fixed forms (model compounds in which proton migration is eliminated by replacing the mobile hydrogen atom with a methyl group) were calculated with full geometry optimization using AMI, PM3, and MNDO methods. The results of aqueous phase semiempirical calculations indicate that 1H form of the studied molecules are more stable than that of 2H form as stated in the literature. (C) 2002 Elsevier Science B.V. All rights reserved.