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221.
Antioxidant and prooxidant effects of nitric oxide (NO) on lipid peroxidation in aqueous and non-aqueous media were examined. In an aqueous solution, NO did not induce peroxidation of unoxidized methyl linoleate (ML) and suppressed the radical initiator-induced oxidation of ML. NO suppressed the Fe(II) ion-induced oxidation of mouse liver microsomes. NO reduced the O2 consumption during the radical initiator-induced oxidation of linoleic acid in an aqueous medium. NO conversion into NO2- in an aqueous medium was not affected by unoxidized ML and was slightly reduced by peroxidizing ML. On the other hand, as well as pure NO2, NO induced peroxidation of unoxidized ML in n-hexane in a dose-dependent fashion. NO did not suppress the radical initiator-induced oxidation of ML in n-hexane. Nitrogen oxide species (NO2 or N2O3) formed by autoxidation was dramatically lost in n-hexane in the presence of unoxidized ML. The results indicated that NO terminated lipid peroxidation in an aqueous medium, whereas NO induced lipid peroxidatiton in a non-aqueous medium. Hence, NO showed both antioxidant and prooxidant effects on lipid peroxidation depending on the solvents. 相似文献
222.
Seunghee Jung Yuki TsukudaRie Kawashima Takumi IshikiAyaka Matsumoto Aya NakaniwaMiho Takagi Takuya NoguchiNobuyuki Imai 《Tetrahedron letters》2013
Acetaminophen analogues containing α-amino acid and fatty acids were easily synthesized in 77–99% yields from the corresponding mixed carbonic carboxylic anhydrides of α-amino acid and fatty acids using aniline derivatives in aqueous MeCN. 相似文献
223.
224.
[reaction: see text] The enantioselective conjugate addition reaction of Et(2)Zn to Meldrum's acid derived acceptors, mediated by a catalyst formed from Cu(O(2)CCF(3))(2) and a phosphoramidite ligand, is reported. Adducts are obtained in useful yields and up to 94% ee. 相似文献
225.
Tetsuya Ishida Makoto Sakakibara Yoshio Ueno Kan-Ichi Hasegawa 《Journal of heterocyclic chemistry》1989,26(3):785-788
The condensation of 2-bromo- or 2, 6-dibromo-4, 8-bis(alkylamino)-1, 5-naphthoquinones with zinc 2-amino-benzeneselenolates gave 1, 5-bis(alkylamino)-4H-benzo[a]phenoselenazin-4-one and the 3- and/or 10-substituted compounds. These phenoselenazone derivatives absorb nearly infrared light and can be used as optical recording media for a laser beam. 相似文献
226.
A new acetylenic compound from the rhizomes of Atractylodes chinensis and its absolute configuration
Nakai Y Sakakibara I Hirakura K Terabayashi S Takeda S 《Chemical & pharmaceutical bulletin》2005,53(12):1580-1581
A new acetylenic compound "atractyloyne", (3S,4E,6E,12E)-1-isovaleryloxy-tetradeca-4,6,12-triene-8,10-diyne-3,14-diol (1) was isolated from the rhizomes of Atractylodes chinensis (Compositae) together with a known compound (4E,6E,12E)-3-isovaleryloxy-tetradeca-4,6,12-triene-8,10-diyne-1,14-diol (2). These structures were determined on the basis of the spectroscopic data and chemical evidence, and the absolute configuration of 1 was established by the modified 2-methoxy-2-trifluoromethylphenylacetic acid (MTPA) method. 相似文献
227.
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229.
Takumi Mizuno Noriaki Okamoto Takatoshi Ito Toshiyuki Miyata 《Heteroatom Chemistry》2000,11(6):428-433
Sulfur‐assisted carbonylation of 2‐aminobenzonitriles with carbon monoxide using K2CO3 as a base under ambient conditions (1 atm, 20°C) to afford 2‐hydroxy‐4‐mercaptoquinazolines in excellent yields was found. This carbonylation was applied to chemical fixation of carbon dioxide under mild conditions. Carbon dioxide (1 atm) easily reacted with 2‐aminobenzonitriles at 20°C assisted by 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) to give 2,4‐dihydroxyquinazolines in excellent yields. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:428–433, 2000 相似文献
230.
Mikio Sakakibara Dazhong Wang Kiyoshi Ikeda Kimihiro Suzuki 《Ultrasonics sonochemistry》1994,1(2):S107-S110
Milk fermentation with Lactobacillus delbrueckii under ultrasonic irradiation was carried out in a 450 cm3 bioreactor with a polyethylene film bottom. Ultrasonic irradiation increased the hydrolysis of lactose in milk but decreased the cell viability. However, the viable cell count increased again when the ultrasound was stopped, because ultrasound did not destroy the ability for cell propagation. When the sonication power was 17.2 kW m-2 and the sonication period was 3 h, 4.9 × 108 cfu cm-3 of the viable cell count and 55% lactose hydrolysis were attained. In contrast, the viable cell count was 2 × 109 cfu cm-3 and 35.6% lactose was hydrolysed in control fermentation. 相似文献