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1.
It has been shown by the ESR of spin probes that thionin initially interacts with with negatively charged membranes electrostatically and then passes into the membranes to a depth comparable with the length of the hydrophobic sections of the protein loops.Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Brigham Young University, Provo, Utah, USA. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 594–597, July–August, 1993.  相似文献   
2.
    
The interaction of α-methacrolein with mixedtrans- andcis-alloocimenes on β zeolite has been studied at room temperature in a solvent under various conditions. The scheme of the process has been specified including the formation of (4+2) and (3+2)-cycloaddition products and strongly adsorbed alloocimene species.  相似文献   
3.
Derivatives of 3-O-acetyl-18-H-glycyrrhetic acid were synthesized. Their structures and membrane activities were studied.  相似文献   
4.
Reactions of camphene, -fenchene, limonene, caryophyllene, - and -pinenes, verbenol, walterol, and verbenone with acylating agents in the presence of clay K-10 and wide-porous -zeolite were studied. Presumable schemes and rules of the occurring processes were considered.  相似文献   
5.
Transformations of epoxide derived from nopol in the presence of natural askanite-bentonite clay were studied. The major products of the isomerization in the cold are diols possessing a p-menthane skeleton, which are readily converted into bicyclic ethers when the reaction is carried out at room temperature.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1483–1487.Original Russian Text Copyright © 2004 by Ilina, Volcho, Korchagina, Salakhutdinov, Barkhash.  相似文献   
6.
Isoflavonoids (-)-medicarpin, (-)-vestitol, and formononetin and butylphenols raspberry ketone and rhododendrol were isolated for the first time from the ethylacetate extract of Hedysarum thienum roots by column chromatography. GC-MS showed that the ethylacetate extract contained fatty acids, the principal ones being palmitic, linoleic, oleic, behenic, and lignocerinic. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 6–9, January–February, 2007.  相似文献   
7.
The reactivity of allyl alcohols of the pinane series and of their epoxides in the presence of montmorillonite clay in intra‐ and intermolecular reactions was studied. Mutual transformations of (+)‐trans‐pinocarveol ((+)‐ 2 ) and (?)‐myrtenol ((?)‐ 3a ) were major reactions of these compounds on askanite–bentonite clay (Schemes 1 and 2). However, the two reactions gave different isomerization products, indicating that the reactivity of the starting alcohol (+)‐ 2 or (?)‐ 3a was different from that of the same compound (+)‐ 2 or (?)‐ 3 formed in the course of the reactions. (?)‐cis‐ and (+)‐trans‐Verbenol ((?)‐ 16 and (+)‐ 12 , resp.), as well as (?)‐cis‐verbenol epoxide ((?)‐ 20 ) reacted with both aliphatic and aromatic aldehydes on askanite–bentonite clay giving various heterocyclic compounds (Schemes 4, 5 and 7); the reaction path depended on the structure of both the terpenoid and the aldehyde.  相似文献   
8.
The electronic structure of the benzaldehyde molecule has been studied by X-ray emission spectroscopy. The gas-phase O-K- and C-K-spectra of this compound have been obtained. MNDO quantum-chemical calculations have been carried out. The structure of the MO's of benzaldehyde has been compared with those of benzene and formaldehyde molecules. The character of the p-p interaction of the phenyl and formyl fragments has been considered. The contribution of the latter to the highest occupied molecular orbitals of the-system has been shown to be small.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1033–1037, June, 1994.  相似文献   
9.
Russian Chemical Bulletin - A series of compounds with a hydrogenated 2H-chromene skeleton was synthesized by the reaction of ketones and available para-menthane monoterpenoid (—)-isopulegol....  相似文献   
10.
The reactivity of verbenol epoxide and isopulegol in supercritical solvents in the presence of aromatic aldehydes was studied using a flow type reactor and a heterogeneous catalyst (Al2O3) or no catalyst. The intramolecular transformations or interactions of reagents with the solvent prevailed in all cases; the yield of the products of intermolecular reactions of terpenoids with aldehydes was up to 1%. The aldehydes did not interact with verbenol epoxide but produced a considerable effect on the distribution of its isomerization products.  相似文献   
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