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931.
Nishioka H Uesugi K Ueda N Kondo Y Tsuji M Abe H Harayama T Hamasaki T Baba M Takeuchi Y 《Chemical & pharmaceutical bulletin》2011,59(8):1075-1076
Optically active structural isomers (1b-f and dst-1b-f) of 3',4'-di-(O)-(-)-camphanoyl-(+)-khellactone (DCK) were synthesized and their anti-human immunodeficiency virus (HIV) activity was investigated. The value of the sensitivity index (SI) of 1b was greater than that of DCK. 相似文献
932.
Ono M Eguchi K Konoshita M Furusawa C Sakamoto J Yasuda S Ikeda T Okawa M Kinjo J Yoshimitsu H Nohara T 《Chemical & pharmaceutical bulletin》2011,59(3):392-396
A new labdane-type diterpenoid glucoside and two new labdane-type diterpenoids were isolated from the fruit (chasteberry) of Vitex agnus-castus L. (Verbenaceae) along with 14 known compounds comprising seven labdane-type diterpenoids, one halimane-type diterpenoid, two oleanane-type triterpenoids, two ursane-type triterpenoids, one aromadendrane-type sesquiterpenoid, and one flavonoid. Their structures were characterized on the basis of spectroscopic data as well as chemical evidence. Furthermore, the antioxidative activities of the flavonoid were evaluated using five different analyses. 相似文献
933.
El-Aasr M Fujiwara Y Takeya M Ono M Nakano D Okawa M Kinjo J Ikeda T Miyashita H Yoshimitsu H Nohara T 《Chemical & pharmaceutical bulletin》2011,59(11):1340-1343
Garlicnin A (1), a new stable, sulfur-containing compound isolated from a fraction of the acetone extracts of Allium sativum L. garlic bulbs, showed the potential to suppress tumor cell proliferation by inhibiting the polarization of M2 alternatively activated macrophages, and its structure was characterized as 3,4-dimethyl-5-(4,5-dithia-1E,7-octadiene)-tetrahydrothiophene-2-sulfoxide-S-oxide, on the basis of the results of spectroscopic analysis results. 相似文献
934.
Preferential carbene insertion into Ge-H vs. other heavier group 14 hydrides via samarium carbenoids
The relative reactivities of Zn, Al, and Sm carbenoids in the chemoselective carbene insertion reaction of heavier group 14 hydrides were studied. By variation of the reaction protocols using Sm carbenoids, insertion reaction can favour the Ge-H bonds to give Ge-alkylated derivatives in good to high yield. 相似文献
935.
Funasako Y Mochida T Inagaki T Sakurai T Ohta H Furukawa K Nakamura T 《Chemical communications (Cambridge, England)》2011,47(15):4475-4477
A paramagnetic ferrocenium-based ionic liquid that exhibits a magnetic memory effect coupled with a liquid-solid phase transformation has been developed. Based on field alignment of the magnetically anisotropic ferrocenium cation, the magnetic susceptibility in the solid state can be tuned by the weak magnetic fields (<1 T) of permanent magnets. 相似文献
936.
Toru Takahashi Mayu Fukagawa Takao Sakurai Hitoshi Hoshino 《Journal of separation science》2020,43(3):657-662
The significant demands for single nucleotide polymorphism detection and genotyping assays have grown. Most common assays are based on the recognition of the target sequence by the hybridization with its specific probe having the complementary sequence of the target. Herein, a simple, label‐free, and economical non‐hybridization assay was developed for single nucleotide polymorphism detection and genotyping, based on the direct discrimination of single base mutation by simple capillary electrophoresis separation for single‐stranded DNA in an acidic electrophoretic buffer solution containing urea. Capillary electrophoresis separation of single‐base sequential isomers of DNA was achieved due to charge differences resulting from the different protonation properties of the DNA bases. Single nucleotide polymorphism detection and genotyping were achieved by discriminating the electropherogram pattern change, that is, peak number in the electropherogram, obtained by the proposed method. The successful practical application of the proposed method was demonstrated through single nucleotide polymorphism detection and genotyping on a known gene region of 84‐mer, in which guanine to adenine single‐base mutation is commonly observed, using a human hair sample in combination with genomic DNA extraction, polymerase chain reaction amplification, DNA purification from polymerase chain reaction products, and capillary electrophoresis separation. 相似文献
937.
Prof. Chihiro Kachi-Terajima Tasuku Eiba Rikako Ishii Prof. Hitoshi Miyasaka Yuta Kodama Prof. Toshiaki Saito 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22232-22237
Spin ice is an exotic type of magnetism displayed by bulk rare-earth pyrochlore oxides. We discovered a spin ice-like magnetic relaxation of [{Mn(saltmen)}4{Mn(CN)6}](ClO4)⋅13 H2O (saltmen2−=N,N′-(1,1,2,2-tetramethylethylene)bis(salicylideneiminate)). This magnetic system can be considered as a two-dimensional network of MnIII salen-type single-molecule magnets (SMMs) in which each SMM unit (ST=4) has two orthogonally oriented axial anisotropies and is connected ferromagnetically through the [Mn(CN)6]3− unit (S=1). This work illustrates that a two-dimensional SMM network with competition between the ferromagnetic interaction and local noncollinear magnetic anisotropies on SMMs is a new type of magnetic system exhibiting slow relaxation of magnetization with a Davidson-Cole-type broad distribution of the relaxation time. 相似文献
938.
The effects of sensitizer, alcohol, and reaction temperature on the photosensitized polymerization of methyl methacrylate in cyclohexane-alcohol mixtures were investigated. A maximum conversion was indicated at a certain concentration of alcohol in the mixture for the systems sensitized with quinones such as anthraquinone, 2-tert-butylanthraquinone, and α-naphthoquinone, while it was not observed for the benzophenone-sensitized system. The concentration of alcohol corresponding to the maximum conversion increased in the order methanol < ethanol < n-propanol < n-butanol, and shifted to the lower side by raising the reaction temperature from 20 to 40°C. Based on the absorption and ESR spectra of irradiated solution of quinones, reasons for maximum conversion at an optimum concentration of alcohol are discussed. 相似文献
939.
Thermal degradation behavior of six alkyl vinyl ketone (RVK) polymers and copolymers with styrene was investigated by means of infrared spectrometry (IR), thermogravimetry (TG), derivative TG (DTG), and differential scanning calorimetry (DSC). The observed TG curves of the RVK polymers changed with both structure of their substituents and initiators used, and the temperature of the beginning of weight loss for the radical polymers increased in the order: poly(methyl isopro-penyl ketone) < poly(methyl vinyl ketone) < poly(ethyl vinyl ketone) < poly(isopropyl vinyl ketone) < poly(tert-butyl vinyl ketone). From the infrared spectral determination of thermally degraded polymers, the formation of a cyclized structure was observed. It was also found from the results of thermal degradation of the RVK copolymers with styrene at 210° C that the formation of such a cyclized unit tended to increase in the order: tert-butyl vinyl ketone < isopropyl vinyl ketone < ethyl vinyl ketone < methyl vinyl ketone. 相似文献
940.
Cellulose peroxides derived from various cellulose derivatives with hydrogen peroxide were investigated. Fibrous carboxy-methyl cellulose, periodic acid-oxidized cellulose, and methyl vinyl ketone-treated cellulose were employed as cellulose derivatives. Carboxyl and carbonyl groups in the cellulose derivatives were believed to react with hydrogen peroxide to form peroxides with structures of peracid and α-hydroxyhydroperoxide types, respectively. The decomposition of the cellulose peroxides and their abilities to initiate grafting reaction were examined. 相似文献