- Kinetics of procaterol auto-oxidation in buffered acid solutions
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The kinetics of procaterol (1) degradaton in buffered acidic solutions (pH 4-6) was investigated using a HPLC procedure. The effect of temperature and ferric ions on the reaction rate was estimated. In acidic solutions, 1 undergoes pseudo first-order degradation with an induction period. The first-order rate constant for degradation increased and the induction period decreased with an increase in pH. Ferric ions catalyzed the degradation reaction and decreased the induction period. At pH 6, the activation energy of the reaction was 34.5 kcal/mol/deg. The results of this study indicate that 1 in solution is more stable at acidic pH, in the absence of heavy metal ions, and protected from air.
- Chen,Chafetz
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Read Online
- O-prenylated carbostyrils as a novel class of 15-lipoxygenase inhibitors: Synthesis, characterization, and inhibitory assessment
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Catalyzed peroxidation of unsaturated lipid in animals and plants intimately is linked to the activity of 15-Lipoxygenase enzymes. Lipoxygenases (LOXs) are well known to play an important role in many acute and chronic syndromes such as inflammation, asthma, cancer, and allergy. In this study, a series of mono prenyloxycarbostyrils were synthesized and evaluated as potential inhibitors of soybean 15-Lipoxygenase (SLO) and their inhibitory potencies were compared to mono prenyloxycoumarins which had been reported in the previous works. The synthetic compounds inhibit lipoxygenase enzyme by competitive mechanism like the prenyloxy coumarins. The results showed that position and length of the prenyl moiety play the important role in lipoxygenase inhibitory activity. Among all of the synthetic compounds (coumarin and carbostyril derivatives), 5-farnesyloxycoumarin and 8-farnesyloxycarbostyril demonstrated the best inhibitory activity by IC50?values of 1.1?μM and 0.53?μM, respectively.
- Alavi, Seyed Jamal,Zebarjadi, Amir,Bafghi, Mahdi Hosseini,Orafai, Hossein,Sadeghian, Hamid
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p. 894 - 902
(2021/09/08)
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- Preparation method of indacaterol intermediate 5-chloracetyl-8-benzyloxy-2(1H)-quinolinone
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The invention discloses a preparation method of an indacaterol intermediate 5-chloracetyl-8-benzyloxy-2(1H)-quinolinone. The method includes: taking o-methoxyaniline, cinnamoyl chloride, aluminium trichloride, trifluoromethanesulfonic acid, chloroacetyl chloride, and benzyl bromide as the raw materials, and carrying out four-step reaction, i.e. amidation reaction, ring closing reaction, Friedel-Crafts reaction, and hydroxylation reaction. The preparation method provided by the invention has the advantages of high yield, low cost, few three waste, easy operation and safety, and is suitable forindustrialization.
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Paragraph 0023; 0024
(2018/04/02)
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- Method for preparing hydroxyl-2(1H)-quinolinone
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The invention discloses a method for preparing hydroxyl-2(1H)-quinolinone, and belongs to the field of organic chemistry. The method comprises the following steps: enabling an aminophenylboric acid compound and trans-beta-aryl acryloyl chloride to react under the existence of triethylamine or pyridine so as to generate a trans-amide intermediate, and then carrying out temperature rising reaction in an organic solvent under the existence of aluminum chloride anhydrous and B(C6F5)3; cooling after completing the reaction, and adding hydrogen peroxide for oxidization, thus obtaining the hydroxyl-2(1H)-quinolinone. The method disclosed by the invention has the advantages that raw materials are easy to obtain, hydroxyl quinolinone products in different positions can be obtained through differentinitial raw materials, and an existing synthetic route is enriched.
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Paragraph 0075; 0076; 0081; 0082
(2018/03/28)
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- Study on Relationship Between Fluorescence Properties and Structure of Substituted 8-Hydroxyquinoline Zinc Complexes
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Organic light-emitting diodes (OLEDs) produced from 8-hydroxyquinoline metal complexes play a vital role in modern electroluminescent devices. In this manuscript, a series of 8-hydroxyquinoline derivatives were synthesized by different methods and their corresponding zinc metal complexes were prepared. The UV and fluorescence properties of the complexes were measured aiming to understand the effect of substituents at the quinoline ring on the fluorescence properties of the complexes. When the C-5 of 8-hydroxyquinoline was replaced by halogen group, the fluorescence emission wavelengths had been red-shifted, at the same time, blue-shifted of fluorescence emission wavelength was observed when the C-5 position of 8-hydroxyquinoline was substituted by electron-withdrawing group. When the C-4 position of 8-hydroxyquinolie was substituted by methyl or the C-5 position was substituted by sulfonic acid group, the corresponding zinc complexes had higher fluorescence intensity than 8-hydroxyquinolie zinc.
- Jianbo, He,Tingting, Zhou,Yongjing, Cao,Yuanyuan, Zhang,Weiqing, Yang,Menglin, Ma
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p. 1121 - 1126
(2018/08/17)
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- Synthesis and evaluation of radioiodinated 1-{2-[5-(2-methoxyethoxy)-1H-benzo[d]imidazol-1-yl]quinolin-8-yl}piperidin-4-amine derivatives for platelet-derived growth factor receptor β (PDGFRβ) imaging
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Platelet-derived growth factor receptor β (PDGFRβ) is a transmembrane tyrosine kinase receptor and it is upregulated in various malignant tumors. Radiolabeled PDGFRβ inhibitors can be a convenient tool for the imaging of tumors overexpressing PDGFRβ. In this study, [125I]-1-{5-iodo-2-[5-(2-methoxyethoxy)-1H-benzo[d]imidazol-1-yl]quinoline-8-yl}piperidin-4-amine ([125I]IIQP) and [125I]-N-3-iodobenzoyl-1-{2-[5-(2-methoxyethoxy)-1H-benzo[d]imidazol-1-yl]quinolin-8-yl}-piperidin-4-amine ([125I]IB-IQP) were designed and synthesized, and their potential as PDGFRβ imaging agents was evaluated. In cellular uptake experiments, [125I]IIQP and [125I]IB-IQP showed higher uptake by PDGFRβ-positive cells than by PDGFRβ-negative cells, and the uptake in PDGFRβ-positive cells was inhibited by co-culture with PDGFRβ ligands. The biodistribution of both radiotracers in normal mice exhibited hepatobiliary excretion as the main route. In mice inoculated with BxPC3-luc (PDGFRβ-positive), the tumor uptake of radioactivity at 1 h after the injection of [125I]IIQP was significantly higher than that after the injection of [125I]IB-IQP. These results indicated that [125I]IIQP can be a suitable PDGFRβ imaging agent. However, further modification of its structure will be required to obtain a more appropriate PDGFRβ-targeted imaging agent with a higher signal/noise ratio.
- Effendi, Nurmaya,Ogawa, Kazuma,Mishiro, Kenji,Takarada, Takeshi,Yamada, Daisuke,Kitamura, Yoji,Shiba, Kazuhiro,Maeda, Takehiko,Odani, Akira
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p. 5576 - 5585
(2017/10/06)
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- Oxidative Cleavage of Styrenes Catalyzed by a PdIIComplex of an 8-Hydroxyquinolinonate Ligand
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Synthesis and catalytic activity of palladium complexes of 8-(pyridin-2-ylmethoxy)quinolinone (3) were investigated. Complexation of 3 with [Pd(CH3CN)2Cl2] gave the dimeric palladium complex [{N,N-(3)PdCl}2] (4). The structure of 4 was characterized by1H/13C NMR spectroscopy and mass spectrometry, and further confirmed by X-ray crystallography. Complex 4 acts as a catalyst for oxidative cleavage of C=C bonds, and it catalyzes the hydration of styrenes in an anti-Markovnikov Wacker manner to give terminal aldehydes as the initial product, which then undergo C–C cleavage to yield the corresponding benzaldehydes. Systematic studies of this catalysis were performed.
- Jhong, Hong-Ming,Liu, Yi-Hung,Peng, Shie-Ming,Liu, Shiuh-Tzung
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p. 5449 - 5455
(2016/12/16)
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- Sulfonamide peri-substituted bicyclics for occlusive artery disease
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Acyl sulfonamide, peri-substituted, fused bicyclic ring compounds useful for the treatment or prophylaxis of a prostaglandin-mediated disease or condition are disclosed. The compounds are of the general formula A representative example is:
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Page/Page column 64
(2008/06/13)
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- NOVEL COMPOUNDS
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The invention provides compounds of formula (I) wherein m, R1, n, R2, q, X, Y, R3, R4, R5, R6, R7 and R8 are as defined in the specification, processes for their prepa
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Page/Page column 23
(2010/02/12)
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- NOVEL TRICYCLIC SPIRODERIVATIVES AS MODULATORS OF CHEMOKINE RECEPTOR ACTIVITY
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The invention provides compounds of formula (I) wherein m, R1, n, R2, q, p, X, Y, R3, R4, t and, R5 are as defined in the specification, processes for their preparation, pharmaceutical compositions containing them and their use in therapy.
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Page/Page column 49
(2008/06/13)
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- Oxo-rhenium(V) complexes with 8-hydroxyquinoline derivatives
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Compounds of the types ReOCl2(L)(PPh3) and ReOCl(L)2 were prepared by reacting ReOCl3(PPh 3)2 with 8-hydroxyquinoline (HL) and its 2-methyl, 2-chloro, 5-chloro, 5-nitro, 5,7-dichloro, 5,7-dibromo, and 5,7-diiodo derivatives. With the bulky 2-phenyl-8-hydroxyquinoline, only ReOCl 2(L)(PPh3) could be isolated, whereas the still bulkier 2-tert-butyl derivative did not react. For ReOCl2(L)(PPh 3), the coordination of the quinoline oxygen trans to the Re=O bond and the cis-dichloro arrangement in the equatorial plane were established from crystallographic studies on the 2-chloro and the 5,7-dibromo complexes. From the combined data for these various derivatives, the 1H NMR signals could be fully assigned. With both series of compounds, a complex d-d absorption pattern is observed in the visible spectra, corresponding to the excitation of a d electron from the interaxial d orbital in the equatorial plane to the empty dxz and dyz orbitals, which are inequivalent in these low-symmetry systems. Deconvolution revealed the presence of two very weak low-energy components (~10 000 and ~12 000 cm-1), which are assigned to the two expected singlet-triplet transitions, whereas two stronger bands at higher energy (~14 000 and ~17 000 cm-1) originate from the two singlet-singlet transitions. These bands are not substantially displaced by substitution on the 8-hydroxyquinoline rings.
- Sigouin, Olivier,Beauchamp, Andre L.
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p. 460 - 470
(2007/10/03)
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- Structure-affinity profile of 8-hydroxycarbostyril-based agonists that dissociate slowly from the β2-adrenoceptor
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Several carbostyril-based β-agonists have been shown to bind tightly to and slowly dissociate from the β2-adrenoceptor (β2AR). In the present study, the structural features of 8-hydroxy-5-[2-[(1-phenyl-2-methylprop-2- yl)amino]-1-hydroxyethyl]-carbostyril (11a) which contribute to its binding properties at the β2AR were investigated using a series of synthesized analogs. The k(off), estimated by the rate of cAMP decline in DDT1 MF-2 (DDT) cells with a reduced receptor density, K(i) and ligand-induced receptor reductions were determined. All of the derivatives stimulated cAMP accumulation in DDT cells in the sub to mid nanomolar range and elicited the same maximal stimulation as (-)isoproterenol. Derivatives of 11a with side chain N-substitutions comprising 2-methylbutyl, phenylethyl and isopropyl had higher k(off)-values and lower affinities as compared to 11a. Increasing the number of methylenes between the side chain tertiary alpha carbon and phenyl from 1 in 11a to 3 or reducing the number to 0 also resulted in derivatives with higher k(off)- and K(i)-values). In addition, replacement of the 8- hydroxycarbostyril nucleus of 11a with catechol reduced the affinity of the compound for the β2AR by 48-fold and increased its k(off). Only those derivatives with the lowest k(off)-values induced a decrease in the receptor density of DDT cell membranes following a preincubation and extensive washing. The data show that the 8-hydroxycarbostyril nucleus in conjunction with substitutions on the tertiary alpha carbon of the side chain and positioning of the phenyl group are important characteristics determining the high affinity and slow dissociation of 11a from the β2AR.
- Deyrup,Nowicki,Richards,Otero,Harrison,Baker
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p. 168 - 177
(2007/10/03)
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- Preparation of new 3-hydroxyquinoline alkaloid, jineol and its ether derivatives using directed ortho-lithiation of chloroquinoline as the key step
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A new alkaloid, jineol (3,8-dihydroxyquinoline) was conveniently prepared employing directed ortho-lithiation of chloroquinoline for 3-position of quinoline ring. Moreover, the ether derivatives of jineol were obtained by the reaction of jineol with alkyl
- Tagawa, Yoshinobu,Yamashita, Hiroyuki,Nomura, Manami,Goto, Yoshinobu
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p. 2379 - 2387
(2007/10/03)
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- Lewis acid catalyzed reaction of cinnamanilides: Competition of intramolecular and intermolecular Friedel-Crafts reaction
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The first intermolecular Friedel-Crafts reaction of benzene leading to the formation of 3,3-diphenylpropionanilide 7 is described. 4-Methoxyaniline was reacted with cinnamoyl chloride to give 4-methoxycinnamanilide (5a), the treatment of which with aluminum (III) chloride in chlorobenzene at 120 °C or in benzene at 80 °C afforded exclusively 6-hydroxyquinolin-2(1H)-one (3a) or 4'-hydroxy-3,3-diphenylpropionanilide (7a), respectively. The formation of 7a rather than 3a in benzene indicated that an intermolecular Friedel-Crafts reaction occurred prior to the relatively more facile intramolecular ring cyclization. This intermolecular Friedel-Crafts reaction was observed during the attempted ring cyclization of cinnamanilide and its methoxy derivatives in aluminum (III) chloride/benzene. Preparation of 3a can also be achieved in 17% overall yield via the N-oxidation of 6-hydroxyquinoline followed by acetylation and hydrolysis.
- Wang, Tai-Chi,Chen, Yeh-Long,Lee, Kuan-Han,Tzeng, Cherng-Chyi
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- An intermolecular Michael addition of benzene
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The first intermolecular Michael addition of benzene leading to the formation of 3,3-diphenylpropionanilide is described. 2-Methoxyaniline was reacted with cinnamoyl chloride to give 2-methoxycinnamanilide (1) which was treated with aluminum chloride in b
- Wang, Tai-Chi,Chen, Yeh-Long,Lee, Kuan-Han,Tzeng, Cherng-Chyi
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p. 6369 - 6370
(2007/10/03)
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