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1.
We have synthesized a series of (1R,2R,4S,5S,8S)-2,8-diaryl-4-(4-nitrophenyl)-1-aza-3,7-dioxabicyclo[3.3.0]octanes as a result of reaction of (1S,2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediol with aromatic aldehydes. The structure of the compounds obtained was established on the basis of 1H NMR data. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 757–763, May, 2006.  相似文献   

2.
A series of isomeric 2-oxazolidinones has been synthesized from (1S, 2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediol. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 579–584, April, 2006.  相似文献   

3.
Russian Journal of General Chemistry - Bromination of (2E)-3-aryl(hetaryl)-2-[4-aryl(hetaryl)-1,3-thiazol-2-yl]acrylonitriles proceeds regioselectively at the C5 atom of the thiazole ring with the...  相似文献   

4.
Summary A new chiral derivatizing agent (CDA), (1S,2S)-1,3-diacetoxy-1-(4-nitrophenyl)-2-propylisothiocyanate, (S,S)-DANI, was applied to the separation of the enantiomers of unusual amino acids containing two chiral centers. Different β-methyl-α-amino acids (β-MePhe, β-MeTyr and β-MeTrp) and β-amino acids with cycloalkane skeletons (2-aminocyclopentanecarboxylic acid and 2-aminocyclohexanecarboxylic acid) were derivatized and the thiourea derivatives produced were separated by reversed-phase high-performance liquid chromatography. The applicability of this new CDA in the separation of unusual amino acids is demonstrated. The four stereoisomers of the investigated amino acids (except β-MePhe) could be separated in one chromatographic run. Presented at Balaton Symposium on High Performance Separation Methods, Siófok, Hungary, September 1–3, 1999  相似文献   

5.
Individual geometrical isomers of some 1,2,5-trimethyl-4-allyl-4-aryl(hetaryl)aminopiperidines were isolated, and their structures were established. 1,2,5-Trimethyl-4-propargyl-4-aryl(aralkyl)aminopiperidines were obtained from 1,2,5-trimethyl-4-aryliminopiperidines and propargylmagnesium bromide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 942–946, July, 1991.  相似文献   

6.
Reactions of 1-amino-2-nitroguanidine with 2-aryl(hetaryl)-1-nitro-1-ethoxycarbonyl(benzoyl)-ethenes proceed via initial formation the aza-Michael product, are accompanied by liberation of nitroacetic ester (or nitroacetophenone), and result in N-aryl(hetaryl)methylidene-N-(2-nitroguanidino)amines.  相似文献   

7.
Chemistry of Heterocyclic Compounds - Alkyl(hetero)aromatic α-hydroxyamino oximes with the anti configuration of the oxime group reacted with ethyl glyoxylate to form...  相似文献   

8.
The application of (1S,2S)- or (1R,2R)-1,3-diacetoxy-1-(4-nitrophenyl)-2-propylisothiocyanate as a new chiral derivatizing agent for the resolution of compounds possessing an amino group is described. The reagent is easily accessible in both enantiomeric forms after a simple two-step synthesis. Its applicability was demonstrated on the example of the resolution of a series of alpha-amino acids. The diastereomeric thiourea derivatives produced were separated by reversed-phase high-performance liquid chromatography. The effects of pH, temperature and reagent excess on the derivatization kinetics were investigated, as were the effects of pH and organic modifier on the separation.  相似文献   

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A reaction of aliphatic 1,2-hydroxylamino oximes bearing the hydroxylamino group at the secondary carbon atom with aromatic and heteroaromatic aldehydes in acetic acid leads to the corresponding 1-hydroxy-2-aryl(hetaryl)-4,5-dialkylimidazoles in high yields. α-Aryl(hetaryl)-nitrones initially formed by the condensation of 1,2-hydroxylamino oximes with aldehydes are quantitatively converted to the corresponding imidazoles.  相似文献   

11.
A reaction of cyclohexanone phenylhydrazone with (het)aryldihalogenophosphines has been studied. As shown, cyclohexanone phenylhydrazone reacts with phenyldibromophosphine and 5-methyl-2-furyldibromophosphine to provide the corresponding 1,2,3-diazaphospholines in high yields. The diazaphospholines thus obtained have been derivatized. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:81–83, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20074  相似文献   

12.
用DCNPNPT测定江水中季铵盐型阳离子表面活性剂   总被引:4,自引:0,他引:4  
利用三氮烯类试剂与季铵盐型阳离子表面活性剂形成离子缔合物可用于季铵盐型阳离子表面活性剂的测定。如用HDNPAPT[1]、HDAA[2]测定CTMAB、CPB,但其灵敏度有待提高。本文研究了显色剂1 (2,6 二氯 4 硝基苯) 3 (4 硝基苯) 三氮烯(DCNPNPT)[3]与阳离子表面活性剂的显色反应,结果表明,DCNPNPT与CTMAB、CPB反应的表观摩尔吸光系数分别为3 93×104L·mol 1·cm 1,和4 16×104L·mol 1·cm 1,是目前报道的用光度法测定季铵盐型阳离子表面活性剂较灵敏的体系之一。用此法测定了瓯江水中微量阳离子表面活性剂CTMAB、CPB的…  相似文献   

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The MINDO3, MNDO, AM1, and PM3 methods have been used to optimize the geometries of (+)-(4S,5S)-4-(4-nitrophenyl)-1-aza-3,7-dioxabicyclo[3.3.0]octane and (+)-(4S,5S)-4-phenyl-1-aza-3,7-dioxabicyclo-[3.3.0]octane. It has been shown that the stereospecificity, of the reaction of the former with methyl iodide is due to the high stability of one of the possible conformers. Pharmacy Faculty 28, University of the Auvergne, Henri Dunant Place, Clermont-Ferrand, France; Samara State University, Samara 443011, Russia; Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1424–1427, October, 1999.  相似文献   

15.
Acetalscanbesynthesizedinanumberofways.Themainproblemintheacetalformationinacidicmediumistoshifttheequilibriumtotherightbyremovalofthewaterformedduringthereactionl.Wesynthesized(2R,4S,SS)-( )-threo-5-(2,2-dich(4-nitrophenyl)-2-aryl-1,3-dioxanesbyacet...  相似文献   

16.
Aromatization of 4-aryl(hetaryl)tetrahydroimidazo[4,5-c]pyridine-6-carboxylic acids and their lithium salts by the action of dimethyl sulfoxide has been revealed for the first time. Heating of these compounds in DMSO for 5–7 h at 90–95°C leads to the formation of 4-aryl(hetaryl)imidazo[4,5-c]pyridine derivatives as a result of dehydrogenation and decarboxylation. Heating of the corresponding lithium salts generated in situ (DMSO, 90–95°C, 3–5 h) affords difficultly accessible 4-aryl(hetaryl)imidazo[4,5-c]pyridine-6-carboxylic acids.  相似文献   

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Amides of 4-aryl(hetaryl)-2-pyrrolidone-3-carboxylic acids have been prepared via ammonolysis of the corresponding esters of pyrrolidone carboxylic acids. The products structure has been characterized by means of IR, 1H NMR, 1H–13C HMQC, and HMBC spectroscopy.  相似文献   

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