2-Hydroxy-3-(1H-indol-3-yl)propenoic Acid

Spectroscopic, quantum chemical, molecular docking and molecular dynamics investigations of hydroxylic indole-3-pyruvic acid: a potent candidate for nonlinear optical applications and Alzheimer's drug

In this paper, a complete theoretical investigation of hydroxylic indole-3-pyruvic acid (HIPyA) molecule was performed using the DFT quantum chemical, molecular docking and molecular dynamics calculations. The conformational analysis of HIPyA molecule was carried out using density functional theory quantum chemical calculations. The most stable structure of the studied molecule was predicted by means of DFT/B3LYP method with cc-pVTZ basis set. The simulated vibrational frequencies were assigned and proved to be in agreement with the available experimental FT-IR data. The effects of gas phase and solvents on UV-visible spectra of HIPyA molecule were simulated using TD-DFT/B3LYP method with cc-pVTZ basis set. The analysis of the density of states spectrum validates the frontier molecular orbitals results, which reveals the charge transfer interaction in HIPyA molecule. The molecular electrostatic potential surface confirms the electrophilic and nucleophilic reactive sites of the studied molecule. The natural bond orbital analysis evidences the bioactivity of the studied molecule. The obtained first order hyperpolarizability value is 33.596 times greater than urea, which confirms the nonlinear optical activity of HIPyA molecule. The molecular docking analysis reveals that the studied molecule under interest can act as a potent inhibitor against the amyloid β-protein (Aβ) enzyme, which causes the Alzheimer's disease. The molecular dynamics analysis confirms the reliability of the docking results.Communicated by Ramaswamy H. Sarma.

Crystal structures and hydrogen bonding in the co-crystalline adducts of 3,5-di-nitro-benzoic acid with 4-amino-salicylic acid and 2-hy-droxy-3-(1H-indol-3-yl)propenoic acid

The crystal structures of the co-crystal adducts of 3,5-di­nitro­benzoic acid with 4-amino­salicylic acid (a 2:2:0.4-hydrate) and with 2-hy­droxy-3-(1H-indol-3-yl)propenoic acid (a 1:1:1 d⁶-DMSO solvate) show, respectively, polymeric and hexa­molecular hydrogen-bonded and π–π-bonded structures

The structures of the co-crystalline adducts of 3,5-di­nitro­benzoic acid (3,5-DNBA) with 4-amino­salicylic acid (PASA), the 1:1 partial hydrate, C₇H₄N₂O₆·C₇H₇NO₃·0.2H₂O, (I), and with 2-hy­droxy-3-(1H-indol-3-yl)propenoic acid (HIPA), the 1:1:1 d⁶-dimethyl sulfoxide solvate, C₇H₄N₂O₆·C₁₁H₉NO₃·C₂D₆OS, (II), are reported. The crystal substructure of (I) comprises two centrosymmetric hydrogen-bonded R₂²(8) homodimers, one with 3,5-DNBA, the other with PASA, and an R₂²(8) 3,5-DNBA–PASA heterodimer. In the crystal, inter-unit amine N—H⋯O and water O—H⋯O hydrogen bonds generate a three-dimensional supra­molecular structure. In (II), the asymmetric unit consists of the three constituent mol­ecules, which form an essentially planar cyclic hydrogen-bonded heterotrimer unit [graph set R₃²(17)] through carboxyl, hy­droxy and amino groups. These units associate across a crystallographic inversion centre through the HIPA carb­oxy­lic acid group in an R₂²(8) hydrogen-bonding association, giving a zero-dimensional structure lying parallel to (100). In both structures, π–π inter­actions are present [minimum ring-centroid separations = 3.6471 (18) Å in (I) and 3.5819 (10) Å in (II)].