- Norepinephrine and its metabolites are involved in the synthesis of neuromelanin derived from the locus coeruleus
-
In order to elucidate the chemical structure of black to brown pigments, neuromelanins (NMs), in the substantia nigra (SN) and the locus coeruleus (LC) in the central nervous system of humans and other mammalian species during aging, chemical degradative methods are powerful tools. HPLC analysis after hydroiodic acid hydrolysis detected aminohydroxyphenylethylamines, aminohydroxyphenylacetic acids, and aminohydroxyethylbenzenes, which confirmed that SN-NM and LC-NM contain melanin derived not only from dopamine and norepinephrine (NE) but also from several other catecholic metabolites, such as 3,4-dihydroxyphenylalanine, 3,4-dihydroxyphenylacetic acid, 3,4-dihydroxymandelic acid, 3,4-dihydroxyphenylethanol, and 3,4-dihydroxyphenylethylene glycol, in addition to the corresponding Cys-derivatives in varying degrees. However, hydroiodic acid hydrolysis showed that LC-NM produced the same degradation products as were detected in SN-NM. Thus, we needed to develop a new chemical detection method to validate the existence of NE in LC-NM. In the present study, we report that HCl hydrolysis of LC-NM in the presence of thioglycolic acid yields new products arising from substitution of the hydroxyl group by thioglycolic acid at the benzyl position of NE and cysteinyl-NE. This is the first chemical evidence showing that NE and cysteinyl-NE are incorporated into LC-NM.
- Wakamatsu, Kazumasa,Tabuchi, Keisuke,Ojika, Makoto,Zucca, Fabio A.,Zecca, Luigi,Ito, Shosuke
-
p. 768 - 776
(2015/11/11)
-
- Reduction of the nitro group to amine by hydroiodic acid to synthesize o-aminophenol derivatives as putative degradative markers of neuromelanin
-
Neuromelanin (NM) is produced in dopaminergic neurons of the substantia nigra (SN) and in noradrenergic neurons of the locus coeruleus (LC). The synthesis of NM in those neurons is a component of brain aging and there is the evidence that this pigment can be involved in the pathogenesis of neurodegenerative diseases such as Parkinson's disease. NM is believed to derive from the oxidative polymerization of dopamine (DA) or norepinephrine (NE) with the participation of cysteine, dolichols and proteins. However, there are still unknown aspects in the chemical structure of NM from SN (SN-NM) and LC (LC-NM). In this study, we designed a new method to synthesize o-aminophenol compounds as putative degradation products of catecholamines and their metabolites which may be incorporated into NM. Those compounds are aminohydroxyphenylethylamine (AHPEA) isomers, aminohydroxyphenylacetic acid (AHPAA) isomers and aminohydroxyethylbenzene (AHEB) isomers, which are expected to arise from DA or NE, 3,4-dihydroxyphenylacetic acid (DOPAC) or 3,4-dihydroxyphenylmandelic acid (DOMA) and 3,4-dihydroxyphenylethanol (DOPE) or 3,4- dihydroxyphenylethyleneglycol (DOPEG), respectively. These o-aminophenol compounds were synthesized by the nitration of phenol derivatives followed by reduction with hydroiodic acid (HI), and they could be identified by HPLC in HI hydrolysates of SN-NM and LC-NM. This degradative approach by HI hydrolysis allows the identification of catecholic precursors unique to SN-NM and LC-NM, which are present in catecholaminergic neurons.
- Wakamatsu, Kazumasa,Tanaka, Hitomi,Tabuchi, Keisuke,Ojika, Makoto,Zucca, Fabio A.,Zecca, Luigi,Ito, Shosuke
-
p. 8039 - 8050
(2014/07/08)
-
- HARMFUL ARTHROPOD CONTROL COMPOSITION, AND FUSED HETEROCYCLIC COMPOUND
-
Disclosed is a harmful arthropod control composition comprising, as an active ingredient, a fused heterocyclic compound represented by formula (1) [wherein A1 and A2 independently represent a nitrogen atom or the like; R1 and R4 independently represent a halogen atom or the like; R2 and R3 independently represent a halogen atom or the like; R5 and R6 independently represent a linear C1-C6 hydrocarbon group which may be substituted, or the like (provided that both R5 and R6 cannot represent a hydrogen atom simultaneously); and n represents 0 or 1]. The harmful arthropod control composition has an excellent efficacy to control harmful arthropods.
- -
-
Page/Page column 120
(2011/02/18)
-
- HARMFUL ARTHROPOD CONTROL COMPOSITION, AND FUSED HETEROCYCLIC COMPOUND
-
Disclosed is a harmful arthropod control composition comprising, as an active ingredient, a fused heterocyclic compound represented by formula (1) [wherein A1 and A2 independently represent a nitrogen atom or the like; R1 and R4 independently represent a halogen atom or the like; R2 and R3 independently represent a halogen atom or the like; R5 and R6 independently represent a linear C1-C6 hydrocarbon group which may be substituted, or the like (provided that both R5 and R6 cannot represent a hydrogen atom simultaneously); and n represents 0 or 1]. The harmful arthropod control composition has an excellent efficacy to control harmful arthropods.
- -
-
Page/Page column 75
(2011/04/13)
-
- COMPOSITION AND METHOD FOR CONTROLLING ARTHROPOD PESTS
-
The present invention provides: an arthropod pests control composition comprising, as active ingredients, a condensed heterocyclic compound and a neonicotinoid compound; a method for controlling arthropod pests which comprises applying effective amounts of a condensed heterocyclic compound and a neonicotinoid compound to the arthropod pests or a locus where the arthropod pests inhabit; and so on.
- -
-
Page/Page column 200-201
(2011/04/25)
-
- COMPOSITION AND METHOD FOR CONTROLLING ARTHROPOD PESTS
-
The present invention provides: an arthropod pests control composition comprising, as active ingredients, a condensed heterocyclic compound and a pyrethroid compound; a method for controlling arthropod pests which comprises applying effective amounts of a condensed heterocyclic compound and a pyrethroid compound to the arthropod pests or a locus where the arthropod pests inhabit; and so on.
- -
-
Page/Page column 201
(2011/05/06)
-
- COMPOSITION AND METHOD FOR CONTROLLING ARTHROPOD PESTS
-
The present invention provides: an arthropod pests control composition comprising, as active ingredients, a condensed heterocyclic compound and pyriproxyfen; a method for controlling arthropod pests which comprises applying effective amounts of a condensed heterocyclic compound and pyriproxyfen to the arthropod pests or a locus where the arthropod pests inhabit; and so on.
- -
-
Page/Page column 200
(2011/05/06)
-
- COMPOSITION AND METHOD FOR CONTROLLING ARTHROPOD PESTS
-
The present invention provides: an arthropod pests control composition comprising, as active ingredients, a condensed heterocyclic compound and pyridalyl; a method for controlling arthropod pests which comprises applying effective amounts of a condensed heterocyclic compound and pyridalyl to the arthropod pests or a locus where the arthropod pests inhabit; and so on.
- -
-
Page/Page column 200
(2011/05/06)
-
- COMPOSITION AND METHOD FOR CONTROLLING ARTHROPOD PESTS
-
The present invention provides: an arthropod pests control composition comprising, as active ingredients, a condensed heterocyclic compound and a diamide compound; a method for controlling arthropod pests which comprises applying effective amounts of a condensed heterocyclic compound and a diamide compound to the arthropod pests or a locus where the arthropod pests inhabit; and so on.
- -
-
Page/Page column 204
(2011/05/06)
-
- Optimization of the azobenzene scaffold for reductive cleavage by dithionite; development of an azobenzene cleavable linker for proteomic applications
-
In this paper we conducted an extensive reactivity study to determine the key structural features that favour the dithionite-triggered reductive cleavage of the azo-arene group. Our stepwise investigation allowed identification of a highly reactive azo-arene structure 25 bearing a carboxylic acid, at the ortho position of the electron-poor arene and an ortho-Oalkyl-resorcinol as the electron-rich arene. Based on this 2(2′-alkoxy-4′-hydroxyphenylazo) benzoic acid (HAZA) scaffold, the orthogonally protected difunctional azo-arene cleavable linker 26 was designed and synthesized. Selective linker deprotection and derivatization was performed by introducing an alkyne reactive group and a biotin affinity tag. This optimized azo-arene cleavable linker led to a total cleavage in less than 10 s with only 1 mM dithionite. Similar results were obtained in biological media.
- Leriche, Geoffray,Budin, Ghyslain,Brino, Laurent,Wagner, Alain
-
experimental part
p. 4360 - 4364
(2010/09/20)
-
- Regulatory molecules for the 5-HT3 receptor ion channel gating system
-
Substituted benzoxazole derivatives which possess a nitrogen-containing heterocycle at C2 are selective partial agonists of the 5-HT3 receptor. Alteration of substituents on the benzoxazole nucleus affords both agonist-like and antagonist-like compounds, and uniquely modifies the function of the 5-HT3 receptor ion channel gating system. SAR and corroborative computational docking study for these partial agonists successfully explained structure and function of the 5-HT3 receptor.
- Yoshida, Satoshi,Watanabe, Takashi,Sato, Yasuo
-
p. 3515 - 3523
(2008/02/07)
-
- Pyrazolopyrimidines as therapeutic agents
-
The present invention is directed to pyrazolopyrimidine derivatives of formula (I) wherein the substituents are defined herein, which are useful as kinase inhibitors and as such are useful for affecting angiogenesis and diseases and conditions associated with angiogenesis.
- -
-
-
- Reduction of nitrophenols by zinc and ammonium chloride in aqueous medium
-
A simple reduction procedure involving zinc and ammonium chloride in aqueous medium has been employed for the reduction of nitrophenols to aminophenols.
- Sridharan,Karpagavalli,Muthusubramanian,Sivasubramanian
-
p. 2243 - 2244
(2007/10/03)
-
- Pyrazolopyrimidines as therapeutic agents
-
The present invention provides compounds of Formula I, including pharmaceutically acceptable salts and/or prodrugs thereof, where G, R2, and R3 are defined as described herein.
- -
-
-
- Benzoxazole derivatives as novel 5-HT3 receptor partial agonists in the gut
-
A series of benzoxazoles with a nitrogen-containing heterocyclic substituent at the 2-position was prepared and evaluated for 5-HT3 partial agonist activity on isolated guinea pig ileum. The nature of the substituent at the 5-position of the benzoxazole ring affected the potency for the 5-HTs receptor, and the 5-chloro derivatives showed increased potency and lowered intrinsic activity. 5-Chloro-7-methyl-2-(4-methyl-1- homopiperazinyl)benzoxazole (6v) exhibited a high binding affinity in the same range as that of the 5-HT3 antagonist granisetron, and its intrinsic activity was 12% of that of 5-HT. Compound 6v inhibited 5-HT-evoked diarrhea but did not prolong the transition time of glass beads in the normal distal colon even at a dose of 100 times the ED50 for diarrhea inhibition in mice. Compounds of this type are expected to be effective for the treatment of irritable bowel syndrome without the side effect of constipation.
- Sato, Yasuo,Yamada, Megumi,Yoshida, Satoshi,Soneda, Tomoko,Ishikawa, Midori,Nizato, Tetsutaro,Suzuki, Kokichi,Konno, Fukio
-
p. 3015 - 3021
(2007/10/03)
-
- Synthesis and photophysical properties of fluorescent 2,5- dibenzoxazolylphenols and related compounds with excited state proton- transfer
-
A series of new 2,5-dibenzoxazolylphenols and related compounds was prepared by condensation of hydroxy- and methanesulfonamidoterephthalic acids with 2-aminophenols. These displayed excited state intramolecular proton- transfer fluorescence at room temperature and above with quantum yields as high as 0.48 and emission peaks of 492-517 nm. The methanesulfonamido group was found about as effective a proton donor as the phenolic hydroxyl group. Incorporation of substituents onto the benzoxazole moieties increased solubility of the fluors in hydrocarbon solvents in some cases, but reduced quantum yields. These fluors are of interest as wavelength shifters in a scintillating detecting medium for ionizing radiation.
- Kauffman,Bajwa
-
p. 1613 - 1622
(2007/10/02)
-
- Acid-catalyzed amino-migration of O-phenylhydroxylamines
-
The mechanism of amino-migration of O-phenylhydroxylamine (1a) was studied. It was found that 1 rearranges to give 2-aminophenol (50%) and 4-aminophenol (7%) in trifluoroacetic acid (TFA). The predominance of the ortho rearrangement of 1 clearly distinguishes this process from the Bamberger rearrangement. From cross-coupling experiments employing stable isotopes, it was clarified that the ortho rearrangement proceeds intramolecularly and the para rearrangement involves both intra- and intermolecular processes. Good first-order kinetics were obtained for the rearrangement. The Hammett plot (σ+) with a large negative slope (ρ = -7.8) indicates that initial heterolytic N-O bond cleavage of 1 occurs and generates a positive charge on the oxygen atom with considerable delocalization into the aromatic ring. An ion-molecule pair involving a phenoxenium ion and an ammonia molecule as an intermediate rationalizes all of the results. In this pair, intramolecular combination to the ortho position proceeds preferentially over that to the para position. Formation of catechol and hydroquinone can be explained in terms of nucleophilic attack of TFA on the phenoxenium ion in a solvent-separated pair.
- Haga, Naoki,Endo, Yasuyuki,Kataoka, Ken-Ichiro,Yamaguchi, Kentaro,Shudo, Koichi
-
p. 9795 - 9806
(2007/10/02)
-
- Synthesis, Spectral Data and Extraction of Copper by 1-(2'-Hydroxy-5'-alkylphenyl)-1-alkanone Oximes
-
1-(2'-Hydroxy-5'-alkylphenyl)-1-ethanone oximes with a normal alkyl group containing 2 to 12 carbon atoms and 1-(2'-hydroxy-5'-methylphenyl)-1-alkanone oximes containing 1 to 11 carbon atoms in the hydrocarbon chain were synthesized.Spectral data (u.v., i.r., n.m.r. and 13C) of oximes are reported.Four of these oximes were used for copper extraction from acidic solution.The results obtained indicate, that these oximes are better extractants than alkyl derivatives of 2-hydroxybenzophenone oximes.
- Krzyzanowska, Ewa,Olszanowski, A.,Juskowiak, M.
-
p. 617 - 630
(2007/10/02)
-
- Alkyl-substituted benzoxazinorifamycin derivative, process for preparing the same and antibacterial agent containing the same
-
A novel rifamycin derivative having the formula (I): STR1 wherein X1 is an alkyl group with 1 to 6 carbon atoms or a cycloalkyl group with 3 to 8 carbon atoms; X2 is a hydrogen atom or an alkyl group with 1 to 4 carbon atoms; R1 is hydrogen atom or acetyl group; A is a group represented by the formula: STR2 wherein R2 is an alkyl group with 1 to 4 carbon atoms or an alkoxyalkyl group with 2 to 6 carbon atoms and R3 is an alkyl group with 1 to 6 carbon atoms or an alkoxyalkyl group with 2 to 6 carbon atoms, or a group represented by the formula STR3 wherein STR4 is a 3 to 9 membered cyclic amino group with 2 to 8 carbon atoms, R4 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, or salts thereof, a process for preparing the same and antibacterial agents containing the same as an effective ingredient. The rifamycin derivative of the present invention having the formula (I) shows a strong antibacterial activity against the Gram-positive bacteria and the acid-fast bacteria.
- -
-
-
