Supramolecular architecture of phenylcarbamoylated acetone oxime 1,1-diisopropyl-3-phenylurea] complex

Carbamoylated oximes 1 form 1:1 molecular complexes 4 with N,N-dialkyl-N′-phenylurea when stirred in THF or ether at room temperature for short time in good yields. The molecular complexes 4a–e were isolated and characterized by analytical and spectral means. X-ray crystallographic analysis for complex 4a was performed. In this paper, we report the use of complex 4a and its moieties as building blocks to form non-interacting polymeric zigzag chains by inter- and intramolecular hydrogen bonds along b-axis, and details of supramolecular architecture of 4a. There is a intramolecular H–H interaction between hydrogen of urea NH and neighboring hydrogen of diisopropyl's CH linked to the other urea nitrogen. In addition, to obtain the most favorable orientation of the moieties of the title complex, PM3 semi-empirical quantum mechanical calculations were performed and then results from X-ray crystallography and computational modeling were compared.

Atmospheric plasma discharge sterilization effects on whole cell fatty acid profiles of Escherichia coli and Staphylococcus aureus

As an alternative to conventional sterilization methods the plasma ions created from high voltage produce radicals which have a direct impact on microorganisms in water. Cell membrane fluidity is an important factor in survival as the fluidity allows for essential cell functions in which pH and fatty acids play a major role. This study investigated the effect of plasma application upon pH and fatty acid profiles of Escherichia coli and Staphylococcus aureus. Results showed that plasma sterilization is not predominantly a result of changes to pH levels or fatty acid contents in the bacterial cell membrane.     

Supramolecular Architecture in the 1:1 Co-Crystallization of 6,7-Dimethoxy-2-methyl-4-phenylisoquinolinium Cation with Perchlorate Anion

Abstract  X-ray crystallographic analysis of the title organic ion–pair complex, C₁₈H₁₈NO₂ ⁺ · ClO₄ ⁻, reveals that 6,7-dimethoxy-2-methyl-4-phenylisoquinolinium cation is co-crystallized with perchlorate counter-anions in 1:1 ratio. The complex crystallizes in space group P 2 ₁ /n, with a = 8.0226(7) ?, b = 12.2552(7) ?, c = 17.9734(16) ?, β = 93.908(7) °, Z = 4, D _x  = 1.431 g/cm³. Aromaticity of isoquinolinium fragment is considerably deformed by the existence of C–H···O type weak H-bonds, leading to chains of topology C ₃ ³(12)[R ₁²(4)] running along b-axis of the unit cell and pseudo-cyclic centrosymmetric R ₄⁴(24)[2R ₁²(4)] synthons. The weak H-bonds serve to stabilize both the extended structure and molecular geometry of the title complex, in particular the disordered perchlorate anion whose components adopt a distorted tetrahedron. Index Abstract  Molecular and the extended structure of 6,7-dimethoxy-2-methyl-4-phenylisoquinolinium perchlorate, C₁₈H₁₈NO₂ ⁺ · ClO₄ ⁻, were determined by single crystal X-ray diffraction study.     

Plasma treatment of polypropylene fabric for improved dyeability with soluble textile dyestuff

The impact of plasma treatment parameters on the surface morphology, physical-chemical, and dyeing properties of polypropylene (PP) using anionic and cationic dyestuffs were investigated in this study. Argon plasma treatment was used to activate PP fabric surfaces. Activated surfaces were grafted different compounds: 6-aminohexanoic acid (6-AHA), acrylic acid (AA), ethylendiamine (EDA), acryl amide (AAMID) and hexamethyldisiloxane (HMDS). Compounds were applied after the plasma treatment and the acid and basic dyeing result that was then observed, were quite encouraging in certain conditions. The possible formed oxidizing groups were emphasized by FTIR and ATR and the surface morphology of plasma treated PP fibers was also investigated with scanning electron microscopy (SEM).PP fabric could be dyed with acid and basic dyestuffs after only plasma treatment and plasma induced grafting, and fastnesses of the dyed samples were satisfactory.     

Crystallographic and conformational analysis of 2-methyl-3-(2-nitro-phenyl)-4-phenyl-[1,2,4]oxadiazolidin-5-one

Molecular and crystal structure of 2-methyl-3-(2-nitro-phenyl)-4-phenyl-[1,2,4]oxadiazolidin-5-one, C₁₅H₁₃N₃O₄, have been determined by single crystal X-ray diffraction study. The title compound is monoclinic, with a = 10.0313(8) Å, b = 9.0372(5) Å, c = 15.5964(14) Å, β = 96.926(7)^∘, Z = 4, D_x = 1.42 g/cm³, μ (Mo-K_α) = 0.105 mm⁻¹, and space group is P 2₁/c. The structure was solved by direct methods and refined to a final R = 0.036 for 1894 reflections with I > 4σ (I). The crystal structure is stabilized by C–H⋅sO type inter-molecular, C–H⋅sN and C–H⋅sO type intra-molecular, π–π stacking and edge to face (C–H⋅s π-ring) interactions. To enlighten conformational flexibility of the title molecule, selected two torsion angles are varied from −180^∘ to +180^∘ in every 10^∘ separetely and then molecular energy profile is calculated and construed.     

Invariant differental forms on compact nilmanifolds

Let N=G/ be a compact nilmanifold, G a connected, simply connected, nilpotent Lie group with its discrete subgroup and Lie algebra . Let I* ( ) denote the invariant differential forms on .If I* ( ) H* ( ) is an injective map, then G is abelian and N is a torus. Furthermore, N has a formal minimal model. If N is an even-dimensional compact nilmanifold, it has a Kähler structure and invariant symplectic structure if and only if I* ( ) H* ( ) is injective.     

New Methods for the Synthesis of Imidazoline-N-Oxides

Δ³-lmidazoline-3-oxides were prepared by the reaction of corresponding aromatic Schiff bases with syn-2-bromoacetophenone oxime. 5,6-Dihydro-4H-1,2,5-oxadiazines were isolated as byproduct in some instances.     

An imidazolidin-1-ol, nitrone and oxadiazinane ring-chain-ring tautomeric dynamic combinatorial library

A dynamic combinatorial library (DCL) based on benzylidene exchange reactions between imidazolidin-1-ol, nitrone and oxadiazinane (INO) ring-chain-ring tautomers at room temperature is created. The probable mechanism of the reaction is discussed based on Hammett type correlation analyses. The equilibria in the DCL are defined as interconversion of INOAr-X to INOAr-Y as a result of reactions with the corresponding aldehydes Y-ArCHO and X-ArCHO and are shown to depend on the σ constants of the substituents and are described by a simple equation log K_XY = ρσ_dif + log K_XY(X = Y). The prediction of K_XY for any INOAr-X and INOAr-Y interconversion requires only the experimental values of ρ and the known Hammett σ constants of the substituents. The effect of Zn(II) and CF₃SO₃H on the DCL equilibria is also reported.     

Sharp inequalities involving the constant e and the sequence (1 + 1/n) n

Several new and sharp inequalities involving the constant e and the sequence (1 + 1/n) ⁿ are proved.