Benzodioxole grafted spirooxindole pyrrolidinyl derivatives: synthesis, characterization, molecular docking and anti-diabetic activity.

A highly stereoselective, three-component method has been developed to synthesize pyrrolidine and pyrrolizidine containing spirooxindole derivatives. The interaction between the dipolarophile α,ß-unsaturated carbonyl compounds and the dipole azomethine ylide formed in situ by the reaction of 1,2-dicarbonyl compounds and secondary amino acids is referred to as the 1,3-dipolar cycloaddition reaction. The reaction conditions were optimized to achieve excellent stereo- and regioselectivity. Shorter reaction time, simple work-up and excellent yields are the salient features of the present approach. Various spectroscopic methods and single crystal X-ray diffraction examinations of one example of compound 6i validated the stereochemistry of the expected products. The anti-diabetic activity of the newly synthesized spirooxindole derivatives was tested against the α-glucosidase and α-amylase enzymes. Compound 6i was found to exhibit potent inhibition activity against α-glucosidase and α-amylase enzymes which is further evidenced by molecular docking studies.

Monomer spectroscopic analysis and dimer interaction energies on N-(4-methoxybenzoyl)-2-methylbenzenesulfonamide by experimental and theoretical approaches.

In this study, theoretical harmonic vibrational frequencies and geometric parameters of N-(4-methoxybenzoyl)-2-methylbenzenesulfonamide have been investigated by Hartree-Fock (HF), density functional theory (B3LYP hybrid functional) methods with 6-311++G (d,p) basis set, for the first time. Experimental FT-IR (400-4000cm(-1)) and Laser-Raman spectra (100-4000cm(-1)) of title compound in solid phase have been recorded. Interaction energies, N-H⋯O hydrogen bonds, C-H⋯O and aromatic π⋯π stacking interactions in dimer structures of the title compound have been evaluated by the calculation methods. The dimer calculations have aimed to present the efficacy and performance of M06-2X hybrid functional on the intermolecular interactions and more strongly bound systems for the corrected and interaction energy by the counterpoise correction procedure. The interaction energies by M06-2X approach give more stable results than HF and B3LYP, extremely. The more strongly bonds, especially, on N-H⋯O hydrogen bonds and π⋯π interaction for the both dimer structure have also supported that the M06-2X functional of density functional is more effective.

5-(3,5-Di-fluoro-phen-yl)-1-(4-fluoro-phen-yl)-3-tri-fluoro-methyl-1H-pyrazole.

In the title compound, C16H8F6N2, the dihedral angle between the pyrazole and di-fluoro-benzene rings is 50.30 (13)°, while those between the pyrazole and fluoro-benzene rings and between the di-fluoro-benzene and fluoro-benzene rings are 38.56 (13) and 53.50 (11)°, respectively. Aromatic π-π stacking inter-actions between adjacent di-fluoro-benzene rings [centroid-centroid separation = 3.6082 (11) Å] link the mol-ecules into dimers parallel to [21-2].

tert-Butyl 4-{5-[3-(tri-fluoro-meth-oxy)phen-yl]-1,2,4-oxa-diazol-3-yl}piperazine-1-carboxyl-ate.

In the title compound, C18H21F3N4O4, the piperazine ring adopts a chair conformation and the dihedral angle between the oxa-diazole and benzene rings is 6.45 (14)°. The C atoms and their attached H atoms in the piperazine ring are disordered, with site-occupation factors of 0.576 (12) and 0.424 (12). In the crystal, mol-ecules are linked through weak C-H⋯O inter-actions, generating an R 2 (2)(12) motif. Further, secondary C-H⋯O inter-molecular inter-actions link the mol-ecules into C(6) chains along [100].

4-Meth-oxy-N-[(4-methyl-phen-yl)sulfon-yl]benzamide including an unknown solvate.

In the title compound, C15H15NO4S, the dihedral angle between the benzene rings is 78.62 (16)°. In the crystal, adjacent mol-ecules are linked along the c axis into C(4) chains through strong N-H⋯O hydrogen bonds. Mol-ecules are further connected through C-H⋯O hydrogen bonds into a hexa-meric unit generating an R (6) 6(66) motif. Another C-H⋯O inter-action connects the mol-ecules along the c axis, forming C(5) chains. A region of disordered electron density, most probably disordered methanol-water solvent mol-ecules, was treated with the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. The formula mass and unit-cell characteristics do not take into account this disordered solvent.

6-Chloro-N-(pyridin-4-ylmeth-yl)pyridine-3-sulfonamide.

In the title sulfonamide derivative, C11H10ClN3O2S, the dihedral angle between the pyridine rings is 46.85 (12)°. The N atom of the chloro-pyridine ring is anti to the N-H bond. In the crystal, mol-ecules are linked through N-H⋯N hydrogen bonds into zigzag chains parallel to [001] with a C(7) graph-set motif.