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1.
The essential oil ofThymus marschallianus was obtained by steam distillation of freshly-gathered flowering plants growing at various heights of the Trans-Ili Ala-Tau range (Kazakhstan). The number of components detected was 49, of which 35 were identified. No appreciable differences in the composition of the essential oil with a change in the height of growth of the plant were observed. The essential oil ofTh. marschallianus and of a number of species growing in various countries have been compared.Institute of Chemical Sciences, Academy of Sciences of the Kazakh SSR, Alma-Ata. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 510–514, July–August, 1985.  相似文献   
2.
Bi-, tri-, and tetradentate macroheterocylic ligands, i.e., structural analogs of phthalocyanine, are studied by X-ray photoelectron spectroscopy. The X-ray photoelectron spectra of N1s lines of the nitrogen atoms of these compounds are analyzed. The binding energies and integrated intensities of N1s lines of the nitrogen atoms are determined and the effective charges on the nitrogen atoms are calculated. The structures of bi-, tri-and tetradentate macroheterocyclic ligands containing isoindole, benzene, and pyridine fragments are established on the basis of the data obtained.  相似文献   
3.

The behavior of bovine serum albumin as a function of the pH of the medium and the presence in the test systems of symmetrical and asymmetrical hydrophobic porphyrins was investigated. It was established that 4-[(tert-butoxycarbonylamino)acetamido]phenyl group favors stronger protein binding to porphyrin, and this effect enhances in an alkaline medium. Solubilization of protein by porphyrins leads to the fact that the particles are spherical in solution, the hydrodynamic radius of the protein globule reduced in an alkaline medium but in neutral medium, in contrast, increases. By IR spectroscopy it was shown that beta-structuring and the proportion of disordered coils of the polypeptide chain in an alkaline medium increases, because the complexability of the protein towards porphyrin is changes.

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The molecules of 8‐methyl‐7,10‐diphenyl‐5H‐benzo[h]pyrazolo[3,4‐b]quinoline‐5,6(10H)‐dione, C27H17N3O2, (I), are weakly linked into chains by a single C—H...O hydrogen bond, and these chains are linked into sheets by a π–π stacking interaction involving pyridyl and aryl rings. In 8‐methyl‐7‐(4‐methylphenyl)‐10‐phenyl‐5H‐benzo[h]pyrazolo[3,4‐b]quinoline‐5,6(10H)‐dione, C28H19N3O2, (II), the molecules are linked into a three‐dimensional framework structure by a combination of C—H...N, C—H...O and C—H...π(arene) hydrogen bonds, together with a π–π stacking interaction analogous to that in (I).  相似文献   
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7.
Six closely related pyrazolo[3,4‐b]pyridine derivatives, namely 6‐chloro‐3‐methyl‐1,4‐diphenylpyrazolo[3,4‐b]pyridine‐5‐carbaldehyde, C20H14ClN3O, (I), 6‐chloro‐3‐methyl‐4‐(4‐methylphenyl)‐1‐phenylpyrazolo[3,4‐b]pyridine‐5‐carbaldehyde, C21H16ClN3O, (II), 6‐chloro‐4‐(4‐chlorophenyl)‐3‐methyl‐1‐phenylpyrazolo[3,4‐b]pyridine‐5‐carbaldehyde, C20H13Cl2N3O, (III), 4‐(4‐bromophenyl)‐6‐chloro‐3‐methyl‐1‐phenylpyrazolo[3,4‐b]pyridine‐5‐carbaldehyde, C20H13BrClN3O, (IV), 6‐chloro‐4‐(4‐methoxyphenyl)‐3‐methyl‐1‐phenylpyrazolo[3,4‐b]pyridine‐5‐carbaldehyde, C21H16ClN3O2, (V), and 6‐chloro‐3‐methyl‐4‐(4‐nitrophenyl)‐1‐phenylpyrazolo[3,4‐b]pyridine‐5‐carbaldehyde, C20H13ClN4O3, (VI), which differ only in the identity of a single small substituent on one of the aryl rings, crystallize in four different space groups spanning three crystal systems. The molecules of (I) are linked into a chain of rings by a combination of C—H...N and C—H...π(arene) hydrogen bonds; those of (II), (IV) and (V), which all crystallize in the space group P, are each linked by two independent C—H...O hydrogen bonds to form chains of edge‐fused rings running in different directions through the three unit cells; the molecules of (III) are linked into complex sheets by a combination of two C—H...O hydrogen bonds and one C—H...π(arene) hydrogen bond; finally, the molecules of (VI) are linked by a single C—H...O hydrogen bond to form a simple chain.  相似文献   
8.
Physics of Atomic Nuclei - In comparison with calculations, the excess of multimuon events found in many experiments at ultrahigh energies of extensive air showers (EASs) cannot be explained using...  相似文献   
9.
The molecules of the title compound, C26H19Cl2N5, are conformationally chiral, with none of the aryl groups coplanar with the pyrazolo[3,4‐b]pyridine core of the molecule. A single unique N—H...N hydrogen bond links the molecules into two symmetry‐related sets of C(11) chains running parallel to the [011] and [01] directions, respectively, and these two sets of chains are linked into a continuous three‐dimensional framework structure by a single unique C—H...N hydrogen bond which forms a chain parallel to the [100] direction.  相似文献   
10.
The essential oil of the common tansy obtained from a population growing in the Dzhungarain Ala-Tau has been investigated. More than 50 substances have been detected, of which 39, including the main ones, have been identified.Institute of Chemical Sciences, Academy of Sciences of the Kazakh SSR, Alma-Ata. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 716–720, November–December, 1984.  相似文献   
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