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121.
Minoru Tanaka Xin Li Hidemasa Hikawa Takafumi Suzuki Katsuhiko Tsutsumi Masashi Sato Osamu Takikawa Hideharu Suzuki Yuusaku Yokoyama 《Bioorganic & medicinal chemistry》2013,21(5):1159-1165
Indoleamine 2,3-dioxygenase (IDO) plays a significant role in several disorders such as Alzheimer’s disease, age-related cataracts and tumors. A series of novel tryptoline derivatives were synthesized and evaluated for their inhibitory activity against IDO. Substituted tryptoline derivatives (11a, 11c, 11e, 12b and 12c) were demonstrated to be more potent than known inhibitor MTH-Trp. Suzuki–Miyaura cross-coupling reaction of 11a–d with phenylboronic acid proceeded in high yields. In most cases, C5 and C6 substitutions on the corresponding indole ring were well tolerated. The tryptoline derivative 11c is a promising chemical lead for the discovery of novel IDO inhibitors. 相似文献
122.
123.
DNA-synthesis stimulatory activity was found in some tryptic fragments of human /¡-casein by using BALB/c3T3 cells, and two of them were identified as the /¡-casein fragments of Arg[l] to Lys[18] (/¡-CN(f 1 -18)) and of Gln[105] to Lys[l 17] (/¡-CN(fl05 -117)). 相似文献
124.
Synthesis of β-tubanol (VIa) was achieved by the bromination of dihydro-β-tubanol acetate (VIIb) followed by dehydrobromination and the subsequent hydrolysis. 2,2-Dimethyl-5-hydroxy-chromanone as well as its derivatives (IV) and the corresponding chromanols (V) and chromans (VII) were also prepared. 相似文献
125.
Rikisaku Suemitsu Minoru Nakajima Makoto Hiura 《Bioscience, biotechnology, and biochemistry》2013,77(2):100-102
Macrosporin monoluethylether was synthesized by means of condensation between α-resorcylic acid (I) and 3-methoxy-p-toluic acid (II) with the use of conc. sulfuric acid and boric anhydride.From this result macrosporin C16H12O5, a metabolic product of Macrosporium Porri Elliott, was established to be 3,5-dihydroxy-7-methoxy-2-methyl anthraquinone (A). 相似文献
126.
Akira Hasegawa Daikichi Nishimura Takashi Kurokawa Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(10):1773-1776
Paromamine and its related compounds were synthesized by a modified Königs-Knorr reaction of 3,4,6-tri-O-acetyl-2-(2′,4′-dinitroanilno)-α-d-glucopyranosyl bromide with isopropylidene derivatives of 2-deoxystreptamine, streptamine and dihydroconduramine F–4. The condensed products were isolated as their poly N-acetyl derivatives and proved to have α-configuration by PMR spectroscopy in D2O. 相似文献
127.
Norio Kurihara Yuzuru Sanemitsu Tomio Kimura Masaharu Kobayashi Minoru Nakajima Yoshiyuki Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(5):784-797
β-BTC(3, 4/5, 6),1) γ-BTC(3, 4, 6/5), and ε-BTC(3, 4, 5/6) were synthesized from α-BTC (3, 6/4, 5) by stepwise routes. 相似文献
128.
Takaaki Finn Akiko Nakazawa Naoki Sumi Hiroaki Tani Akikazu Ando Minoru Yabuki 《Bioscience, biotechnology, and biochemistry》2013,77(12):2747-2753
A purple non-sulfur bacterium, Rhodopseudomonas sp. No. 7, was isolated from n-propanol–enrichment cultures under anaerobic-light conditions. Strain No. 7 can produce hydrogen from alcohols. The rate of hydrogen production from n-propanol was 34 μl/hr/mg dry cells. Strain No. 7 showed multiplication by budding and the best growth on n-propanol among other organic compounds tested. But its growth on n-propanol was poor under aerobic-dark conditions. NAD-linked alcohol dehydrogenase, NAD-linked aldehyde dehydrogenase, acyl-CoA synthetase and malate synthetase were found in strain No. 7. These enzymes were constitutive. On the other hand, isocitrate lyase was induced in cells grown on ethanol but not on n-propanol. No activity of phenazine methosulfate-linked alcohol dehydrogenase was detected in strain No. 7. 相似文献
129.
Tomoyuki Tsuneya Masakazu Ishihara Haruyasu Shiota Minoru Shiga 《Bioscience, biotechnology, and biochemistry》2013,77(11):2495-2502
Steam distilled oil of quince fruit (Cydonia oblonga Mill.=C. vulgaris Pers., marmelo in Japanese) was analyzed by gas chromatography and gas chromatography-mass spectrometry. Sixty-two compounds, 2 hydrocarbons, 13 esters, 11 alcohols, 11 aldehydes, 11 ketones, 5 lactones and 9 miscellaneous compounds, were identified. Of them, the chemical structures of two new oxide compounds, trans- and cis-3-methyl-5-[(E)-3′-methyl-13′-butadien-1′-yl]tetrahydrofuran, were elucidated by instrumental analyses. 相似文献
130.
Toshio Fujita Katsuzo Kamoshita Takaaki Nishioka Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(8):1521-1528
The electronic and hydrophobic substituent parameters of a number of o-, m- and p- substituted phenyl N-methylcarbamates were estimated by measuring the alkaline catalyzed hydrolysis rate constant and 1-octanol/water partition coefficient. Since some o-substituted derivatives are very potent insecticides, emphasis was placed on determining the ortho substituent effects in terms of the existing free-energy related parameters. The information obtained should be useful in structure-activity studies of carbamate insecticides. 相似文献