- An efficient colorimetric probe for fluoride ion based on schiff base
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A novel colorimetric probe 2-hydroxy-1-naphthylaldehyde-2-quinoline acylhydra-zone (L) was synthesized and its structure was characterized by FT-IR, 1H NMR, 13C NMR and HRMS method. The sensing ability of the probe towards anions (F?, Cl?, Br?, I?, NO3?, AcO?, HSO4?, H2PO4?, ClO4?) was determined by colorimetric, UV–vis and NMR studies. The results showed that L had an efficient colorimetric sensing ability for fluoride ion by changing color from colorless to yellow. The probe L bound to F? in a 1:2 stoichiometric manner. Furthermore, the binding constant of the complex was 1.37 × 109 M?2 with the detection limit of 8.28 × 10?6 M. The recognition mechanism was attributed to the intermolecular proton transfer between the hydroxyl group of the probe L and the fluoride according to 1H NMR titration method.
- Li, Zheng,Wang, Shujun,Xiao, Liwei,Li, Xiaolong,Shao, Xiaona,Jing, Xuemin,Peng, Xiaoxia,Ren, Lilei
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- 5,6,7,8-TETRAHYDRO[1,2,4]TRIAZOLO[4,3-a]PYRAZINE DERIVATIVES AS P2X7 MODULATORS
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The present invention provides a compound of formula (I) or a pharmaceutically acceptable salt thereof wherein A is hydrogen, C1-4alkyl, C3-6cycloalkyl, C1-3alkoxy, C1-3alkoxy C1-4alkyl, C1-2fluoroalkyl, halogen, NR6 R7, optionally substituted heteroaryl (Het), or optionally substituted phenyl, and R1, R2, R3, R4, R5, R6 and R7 are as defined in the description. The compounds or salts are thought to modulate P2X7 receptor function and to be capable of antagonizing the effects of ATP at the P2X7 receptor. The invention also provides the use of the compound or salt in the treatment or prophylaxis of, for example, inflammatory pain, neuropathic pain, visceral pain, rheumatoid arthritis, osteoarthritis or neurodegenerative disorders.
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Page/Page column 81
(2010/11/17)
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- Inhibition of advanced protein glycation by 8-quinolinecarboxylic hydrazide
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Glycation of proteins is believed to be involved in the pathogenesis of diabetic complications, and thus the development of potent inhibitors of protein glycation is highly desirable. We tested the inhibitory effects of 12 hydrazide compounds against protein glycation and compared them with the effects of aminoguanidine (AG), a well-known inhibitor. When bovine serum albumin (BSA) was incubated with 100 mmol/l mannose for 10 days at 37°C in the presence and absence of hydrazide compounds or AG at 1 mmol/l, only p-anisic hydrazide inhibited Amadori product formation. On the other hand, 8 hydrazides as well as AG inhibited the formation of advanced glycation end products (AGEs). 8-Quinolinecarboxylic hydrazide (8-QCH), the most potent hydrazide, was more effective than AG. Neither 8-QCH nor AG affected the spontaneous decrease in Amadori products of preglycated BSA in the absence of sugar, but suppressed the spontaneous increase in AGEs from preglycated BSA, with higher potency of 8-QCH relative to AG. The results indicate that 8-QCH is a more potent inhibitor of AGE formation than AG and suggest that the inhibition mechanisms of 8-QCH and AG resemble each other.
- Miwa, Ichitomo,Tsugawa, Tohru,Koyasu, Katsuya,Terada, Yukimasa
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p. 314 - 320
(2007/10/03)
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