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Two packing polymorphs of 5-hydroxy-1-(4-methylbenzyl)-3-chloro-4-[(4-chlorophenyl)sulfanyl]-1,5-dihydro-2H-pyrrol-2-one are studied by single-crystal and powder X-ray diffraction, IR spectroscopy, and differential scanning calorimetry. Classical hydrogen bonds and CL…O interactions have the fundamental importance for the formation of the supramolecular motif that is identical in both modifications. The difference relates to the packing of 2D layers which is “parallel” in the triclinic modification and of the “herringbone” type in the monoclinic modification. It is shown that close similarity between structural organizations of crystal lattices, which is typical of packing polymorphs, can be accompanied by significant differences between their energies as well as by a high potential barrier upon the transition from the metastable polymorph to its stable form.

This paper presents the results of a comparative study of rock samples from depth intervals of 1705–1728 m of Semilukian–Mendymian (domanik) deposits of the Berezovskaya area and 1379–1394 m of carbonate (domanikoid) deposits of the Dankovian–Lebedyanian horizon of the Zelenogorskaya area of the Romashkino oilfield. It has been shown that rocks with different mineral compositions differ in the content and composition of organic matter (OM), including kerogen, and its resistance to thermal impacts. The yield of extracts from the rocks and the differences in their group, structural-group, and hydrocarbon-group compositions have been determined. According to the molecular-mass distribution of normal and isoprenoid alkanes, the extracts from the rocks are oils of types A1 and A2. Peculiarities in the distribution of higher biomarkers have been revealed, indicating that the hydrocarbons of the examined samples of domanik and domanikoid rocks are genetically uniform in nature, but differ in the geochemical environment of the transformation of the original OM and, possibly, in the effect of migration processes.

Using a complex of physical and chemical methods studied features of the elemental, structural-group, and microelement composition of natural bitumen asphaltenes extracted from bituminous r...

The spectral, aggregation, and adsorption properties of amphiphilic metal complexes of alkylated N-methyl-D-glucamines and lanthanum nitrate and their mixture with hexadecyltrimethylammonium bromide were studied using IR, UV, and 1H NMR spectroscopy, tensiometry, potentiometry, and dynamic and electrophoretic light scattering. The parameters of aggregation and adsorption at the interface were determined and compared with the parameters of the ligands, ligand–inorganic salt mixtures, and traditional cationic surfactants.

Study was conducted of rocks composition and its extracted moving hydrocarbons from Domanic deposits of Tatarstan, differing in location and occurrence depth from 1379 to 1891 m. The rocks are repr...

This work deals with polyfunctional biocompatible amphiphilic isatin derivatives. Isatin-3-acylhydrazones containing a quaternary ammonium moiety (Is-Q-n) with varying hydrophobicity (R = CnH2n+1, where n = 10, 12, 14, 16, 18, 20) were synthesized. Tunable self-assembly behavior, morphology of nanostructures, and their biological activity were modulated by hydrophilic-lipophilic balance of π-amphiphiles and solvent polarity. Self-assembly of Is-Q-n was investigated by tensiometry, conductometry, IR and UV–Vis spectroscopy, fluorimetry and dynamic light scattering. The unexpected values of the physicochemical parameters at long alkyl chain length have been interpreted. The CAC of Is-Q-16 is lower than CMC of classical surfactant CTAB. Solvent-induced self-assembly for Is-Q-16 was observed. The hydrophobic dye Orange OT was solubilized in Is-Q-10 solutions twice better than in CTAB solutions. Is-Q-n self-assembled structures with size 50 nm and 100 nm in a concentration range from 0.01 mM (below CAC) to 10 mM were found. Is-Q-10 forms small associates with size 3 nm. Selective antimicrobial activity of low toxic ammonium salts against Gram-positive bacteria (S. aureus 209p and B. cereus 8035) and fungus Candida albiсans 855–653 was shown. Newly synthesized 1-dodecylisatin derivatives containing a quaternary ammonium moiety may be recommended as antimicrobial agents and for drug solubilization, in particular for drugs capable for π-π stacking interactions.