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The condensation of 2-methyl-5-acetyl-2-oxazolines with p-R-substituted benzaldehydes in the presence of bases gave the corresponding 2-methyl-5-(-aryl-acrylyl)-2-oxazolines, the hydrolysis of which with hydrochloric acid leads to hydrochlorides of alkyl-substituted 1-(p-R-styryl)-2-acetoxy-3-aminobutan-1-ones. Treatment of the latter with bases gives 1-(p-R-styryl)-2-hydroxy-3-N-acetyl-2, 3-alkylbutan-1-ones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1025–1027, August, 1982.  相似文献   

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The synthesis and antifungal activity of a novel series of 3-aryl-5-[(aryloxy)methyl]-3-[(1H-1,2,4-triazol-1-yl)-methyl]-2-methylisoxazolidines are described. The in vitro activity was evaluated in solid agar cultures against a variety of dermatophytes and yeast fungi, while in vivo activity was measured in an immune-compromised mouse model of systemic candidiasis. The activity of the title series was compared to that of ketoconazole and one derivative, the cis-3-(4-chlorophenyl)-5-(4-chlorophenyloxy)methyl analogue 5f was found to possess a similar potency in the in vivo assay. Structure-activity relationship correlations are also discussed.  相似文献   

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The heterocyclic azo compound, 1-[(5-chloro-2-pyridyl)azo]-2-naphthol (5-Cl-β-PAN), forms various coloured metal chelates, which can be extracted with different organic solvents. Chelate stability is greatly affected by pH. The molar absorptivities are usually considerably greater than those of the β-PAN chelate. Although the bathochromic shifts produced on chelation are no greater than those with 5-Br-β-PAN, the selectivity is increased. The reactivity of tri- and tetravalent metal ions is decreased appreciably by introduction of the chlorine. A correct choice of pH, solvent and masking reagent allows 5-C1-β-PAN to be made reasonably selective.  相似文献   

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Metal salts (Co2+, Mn2?, Ni2+) of 2-[(1-hydroxy-2-naphthalenyl)carbonyl]-benzoic acid can be considered as a new class of stabilizers effective against free radical photo-oxidation and singlet oxygen oxidation of cis-1,4-polybutadiene. These metal salts are active by a combination of several important effects such as reducing the number of photons absorbed by polymer chromophores, deactivation of excited carbonyl groups, scavenging of free radicals and quenching of singlet oxygen.  相似文献   

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The acyclic nucleoside phosphonate analogues, 9-[(2-hydroxy-1-phosphonylethoxy)ethyl]guanine 6 , 1-[(2-hydroxy-1-phosphonylethoxy)ethyl]cytosine 7 and 9-[(2-hydroxy-1-phosphonylethoxy)ethyl]adenine 8 , have been prepared by the coupling of a tosylate of the phosphonate side chain 12 with a purine or pyrimidine base followed by deprotection of the blocking groups.  相似文献   

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New highly cytotoxic 3-aminopropyl derivatives of 2-dimethylsilyl-5-trialkylgermylfuran (IC50 1−3 μg⋅ml−1) have been prepared by hydrosilylation of heterocyclic N-allylamines with the corresponding hydrosilane in the presence of Speier’s catalyst. The influence of the amine structure and alkyl substituent at the germanium atom on the cytotoxicity has been investigated.  相似文献   

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Summary Cadmium(II) reacts with l-[(5-chloro-2-pyridyl)azo]-2-naphthol (5-C1--PAN) in aqueous solution; the complex can be extracted with chloroform at pH 9–11 to give a red solution with an absorption peak at 566 nm. The colour in chloroform is stable and the system conforms to Beer's law; optimal range in the chloroform layer for measurement at 1.00-cm cells is 0.1–1 ppm cadmium. Common cations and anions do not interfere. Large amounts of some cations can be masked by potassium cyanide, the cadmium cyanide complex being demasked by formaldehyde. The proposed method is one of the most sensitive procedure for the determination of cadmium. The molar absorptivity in the chloroform extract is 6.6· 104 1 mole–1 cm–2 at 566 nm.
Zusammenfassung Cadmium reagiert mit 1-(5-Chlor-2-pyridyl) azo-2-naphthol, 5-C1--PAN, in wäßriger Lösung; der rote Komplex kann bei pH 9–11 mit Chloroform extrahiert werden und hat ein Absorptionsmaximum bei 566 nm. Die chloroformische Lösung ist stabil und entspricht dem Beerschen Gesetz; für die Messung in l-cm-Küvetten eignen sich am besten 0,1–1 ppm Cd. Übliche Ionen stören nicht. Große Mengen einiger Kationen können mit KCN maskiert werden, wahrend [Cd(CN)4]2– von Formaldehyd gespalten wird. Die vorgeschlagene Methode ist eine der empfindlichsten für die Bestimmung von Cd. Die molare Extinktion des chloroformischen Extraktes betragt bei 566 nm 6,6 · 104 1 · mol–1 · cm–2.
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The A [(2)B1] <--X [(2)A2] band system between 380 and 420 nm was observed in a supersonic jet expansion. The allyl radical was found to dissociate following electronic excitation, releasing a hydrogen atom. Monitoring the appearance of the hydrogen atom photoproduct as a function of the excitation laser wavelength, similar spectral features are observed as in earlier absorption experiments. Time- and frequency-resolved photoionization of the hydrogen atom product provides information on the unimolecular dissociation dynamics. The measured dissociation rates and kinetic energy releases of both allyl radical, C3H5, and partially deuterated allyl radical, C3DH4, suggest direct loss of the central hydrogen atom, leading to allene as the major product.  相似文献   

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Coupling of trimethylsilyl derivative of methyl 1,2,4-triazole-3-carboxylate with 2-O-(chloromethyl)-1,3-di-O-benzyl glycerol, followed by amination and removal of the protecting groups afforded 1-[(2-hydroxy-1-(hydroxymethyl)ethoxy)methyl]-1,2,4-triazole 3- and 5-carboxamides, 1a and 1b, respectively.  相似文献   

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A method for the analysis of the antimycotic drugs 1-[(5-chloro-2-benzofuranyl)(2-chlorophenyl)methyl]-1H-imidazole, 1-[(5-bromo-2-benzofuranyl)phenylmethyl]-1H-imidazole and bifonazole in rabbit plasma, employing gas chromatography-mass spectrometry with selected-ion monitoring, was developed. The procedure involved single-step purification of the biological matrix via liquid-liquid extraction on Extrelut columns and use of a carrier substance to minimize the negative effects of adsorption sites during the gas chromatographic process. The limits of detection ranged from 0.1 to 1.4 ng/ml, starting from a 200-microliter sample. The method was applied to a preliminary evaluation of percutaneous absorption of both drugs in the rabbit after a single administration, in comparison with bifonazole.  相似文献   

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A practical and improved synthesis of (3S,5S)-3-[(tert-butyloxycarbonyl)methyl]-5-[(methanesulfonyloxy)methyl]-2-pyrrolidinone (1) is described. The key transformations involve a highly efficient reaction sequence consisting of ethoxycarbonylation, alkylation, hydrolysis, and decarboxylation to produce compound 10. The process described herein is practical, robust, and cost-effective, and it has been successfully implemented in a pilot plant to produce a multikilogram quantity of mesylate 1.  相似文献   

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1 INTRODUCTIONNeonicotinoids[1~2]areanovelanddistinctclassofinsecticides.Theycombineselectiveactivityagainstinsectswithafavourablesafetyprofile.Neonicotinoidsactatthenicotinicacetylcholinereceptor(nAChR)[3~4].Sincethefirstneonicotinoid,imi-dacloprid(IMI)1wasintroducedtothemarketbyBayerin1991,alotofitsanalogswerereported.Thesecompoundshavethesamestructuralunit,asshowedindashedlineareainIMI.AccordingtothemodelproposedbyYamamotoetal[5],thedistancebetweenthetwonitrogenatomsofIMIisthe…  相似文献   

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1-[(Nitroxyalkoxy)methoxy]-3,3-dialkyl-1-triazene 2-oxides were obtained by the reaction of 3,3-dialkyl-1-hydroxy-1-triazene 2-oxide sodium salts with β- or γ-nitroxyalcohol chloromethyl ethers or by the reaction of 3,3-dialkyl-1-(bromoalkoxymethoxy)-1-triazene 2-oxides with silver nitrate. These compounds can be of interest as new hybrid NO donors in living organisms.  相似文献   

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Infrared (IR) investigation of structurally analogous optically active polymers such as poly[(S)-5-methyl-1-heptene (1)] and poly[(S)-2-methylbutyl vinyl ether (2)] was carried out in the solid state, in the molten state, and in solution. Vibrational data are in accordance with the existence of helical conformations in solution and in the molten state for both polymers, confirming the previous suggestions based on optical rotation measurements. In particular, an accurate examination of the spectral region between 850 and 700 cm?1, where characteristic absorptions of the sec-butyl group occur, enables us to assign the medium intensity band at 827 cm?1 (present in both polymers in the solid state) to the GTTG?T conformation of the side chains.  相似文献   

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