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Three-component 1,3-dipolar cycloaddition reactions between isatin, benzylamine, and α,β-unsaturated ketones at room temperature afforded substituted spiro[indole-3,2′-pyrrolidine] derivatives with good yields. In some cases, only one diastereoisomer was formed. The reaction involved in situ generation of azomethine ylide from isatin and benzylamine. The possibility of formation of different regio- and stereoisomers was analyzed by PM7 semiempirical quantum chemical calculations and NMR spectroscopy.

Bromo-chalcone with containing thiene ring by the reaction of selective de­hyd­ro­bromination of α, β-dibromo ketone at presences of different amines in benzene solution and α-ethoxy-β-bromo-ketone in etha­no­lic solution in good yields were prepared. α, β-Dibromo ketone with the reaction of thiosemicarbazide le­ad to the formation of new pyrazole derivative.

The efficiency of (2E,4E)-1-(2-hydroxy-5-methylphenyl)-5-phenyl-2,4-pentadiene-1-one (1), (2E)-3-[2-(allyloxy)-5-bromophenyl]-1-(2-hydroxy-5-methylphenyl)-2-propen-1-one (2), (E)-4-methyl-2-(3-methyl-4-styryl-4.5-dihydrobenzoisoxazol-6-yl)phenol (3) and 2-{4-[2-(allyloxy)-5-bromophenyl]-3-methyl-4.5-dihydro-1.2-benzisoxazol-6-yl}-4-methylphenol (4) as corrosion inhibitors have been studied by weight loss measurements for St-3 mild steel specimen in brine-kerosene mixture. The corrosion rates of St‑3 steel decreased with increase in concentration of the studied compounds.

Molecular dynamics of benzoxazepin, oxime, pyrazole, and thiosemicarbazone derivatives of some flavanones have been investigated in a solution using NMR. The results confirm the formation of different O–H···O, O–H···N, N···H–N type intramolecular hydrogen bonds in the pyrazole and oxime molecules. The rotational barrier energy and energy of intramolecular hydrogen bonds have been determined. Copyright © 2013 John Wiley & Sons, Ltd.

The formation of hydrogen bonds and the molecular dynamics for molecules (Z)-1-(2-hydroxy-5-methyl-3-nitrophenyl)ethanone oxime and (E)-2-hydroxy-5-methylacetophenone thiosemicarbazone, (E)-4-bromoacetophenone thiosemicarbazone have been investigated in solution using NMR. The results confirm the formation of different O-H…O type intramolecular hydrogen bonds in the oxime molecule. The rotational barrier energy and energy of intramolecular hydrogen bonds have been determined.

The formation of hydrogen bonds and molecular dynamics for the molecules cis-1-(2-hydroxy-5-methylphenyl)ethanone oxime (I) and N-(2-hydroxy-4-methylphenyl)acetamide (II) have been investigated in solution using NMR. The results confirm the formation of OH···O, OH···N and O···HN type inter- and intramolecular hydrogen bonds. Spin-lattice relaxation times (T1), activation energy of molecular dynamics and energy of intramolecular hydrogen bonds have been determined. Copyright © 2010 John Wiley & Sons, Ltd.

The formation of hydrogen bonds and molecular dynamics of alkenylphenol derivatives has been investigated in solution using nuclear magnetic resonance. The results confirm formation of an N···H, O···H-type intramolecular hydrogen bond. The spin–lattice relaxation times (T 1) and activation energy of molecular dynamics have been investigated confirming the importance of relaxation times as a very sensitive tool for studying molecular mobility.

The light pseudoscalar π0, η and η′ mesons electromagnetic transition γ* + γ* → M form factors FMγ*(Q2,ω) are calculated, applying the perturbative QCD factorization formula and the frozen coupling constant approximation. In the computations the O(αS) order expression for FMγ*(Q2,ω) and the mesons' infrared renormalon corrected distribution amplitudes are used. In the case of the η and η′ mesons, the SUf(3) ordinary octet-singlet mixing scheme is utilized. Comparisons are made with the results obtained, employing the mesons' ordinary distribution amplitudes and with γ + γ* → M transition form factors.

Synthesis and NMR investigations of cyclohexenone, flavanone, isoxazol and indazole derivatives of (2E)-3-[2-(allyloxy)-5-bromophenyl]-1-(2-hydroxy-5-methylphenyl)-2-propen-1-one (I, chalcone) have been carried out. The results confirm the formation of O-H•••O type intramolecular hydrogen bond and intramolecular cyclization in the (2E)-3-[2-(allyloxy)-5-bromophenyl]-1-(2-hydroxy-5-methylphenyl)-2-propen-1-one (I), the presence of conformational and keto-enol tautomeric transitions in the 6-acetyl-5-[2-(allyloxy)-5-bromophenyl]-3-(2-hydroxy-5-methylphenyl)-2-cyclohexen-1-one (II), conformational transitions in the 2-{4-[2-(allyloxy)-5-bromophenyl]-3-methyl-4.5-dihydro-1.2-benzisoxazol-6-yl}-4-methylphenol (III) and 2-{4-[2-(allyloxy)-5-bromophenyl]-3-methyl-4.5-dihydro-1H-indazol-6-yl}-4-methylphenol (IV). The conformational and keto-enol tautomerism in the investigated compounds have been also confirmed by chemical methods.

Power-suppressed corrections to the light pseudoscalar (π, K) and longitudinally polarized ρ-meson electromagnetic form factors FM (Q2) are estimated by means of the running coupling constant method. In calculating the mesons distribution amplitudes (DAs) found, the "naive non-abelianization" approximation is used. Comparisons are made with FM(Q2) obtained using the "ordinary" DAs and running coupling constant method, as well as with frozen coupling approximation's results.

Molecular dynamics of cyclohexenone derivatives of (2E,4E)-1-(2-hydroxy-5-methylphenyl)-5-phenyl-2,4-pentadiene-1-one (chalcone) has been investigated in solutions using NMR. The results confirm the formation of O-H⋯O intramolecular hydrogen bond and the presence of keto–enol tautomeric transitions in the (E)-6-acetyl-3-(2-hydroxy-5-methylphenyl)-5-styryl cyclohex-2-en-1-one. The free energy of activation for the keto–enol tautomeric transitions has been calculated. The keto–enol tautomerism in the investigated compound has been also confirmed by chemical method. Copyright © 2013 John Wiley & Sons, Ltd.