A FACILE SYNTHESIS AND REACTIONS OF AMINO SELENOLO[2,3-b]PYRIDINE CARBOXYLATE

Incorporating selenium metal bonded to the pyridine nucleus was achieved by the reaction of selenium metal with 2-chloropyridine carbonitrile 1 in the presence of sodium borohydride as reducing agent. The resulting non isolated selanyl sodium salt was subjected to react with various α-halogenated carbonyl compounds to afford the selenyl pyridine derivatives 3a-f which compounds 3a-d underwent Thorpe-Ziegler cyclization to give 1-amino-2-substitutedselenolo[2,3-b]pyridine compounds 4a-d, while the other compounds 3e,f failed to be cyclized. Basic hydrolysis of amino selenolo[2,3-b]pyridine carboxylate 4a followed by decarboxylation furnished the corresponding amino selenolopyridine compound 6 which was used as a versatile precursor for synthesis of other heterocyclic compound 7-16. All the newly synthesized compounds were established by elemental and spectral analysis (IR, 1H NMR) in addition to mass spectra for some of them hoping these compounds afforded high biological activity.

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ChemInform Abstract: Facile Synthesis and Biological Activity of Sulfonate Ester Containing Imidazolylpyridine, Imidazo(4,5-b)pyridine and Imidazo(5′,1′:2,3)imidazo(4,5-b)pyridine Derivatives.

ChemInform ◽

10.1002/chin.198933171 ◽

1989 ◽

Vol 20 (33) ◽

Author(s):

M. M. GIRGES ◽

M. M. ABOU EL-ZAHAB ◽

M. A. HANNA

Keyword(s):

Biological Activity ◽

Pyridine Derivatives ◽

Facile Synthesis ◽

Sulfonate Ester

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The Hydrolysis of Imidate Salts. Stereoelectronic Control in the Cleavage of the Hemiorthoamide Tetrahedral Intermediate

Canadian Journal of Chemistry ◽

10.1139/v75-394 ◽

1975 ◽

Vol 53 (18) ◽

pp. 2791-2807 ◽

Cited By ~ 35

Author(s):

Pierre Deslongchamps ◽

Serge Dubé ◽

Claude Lebreux ◽

Dennis R. Patterson ◽

Roland J. Taillefer

Keyword(s):

Alkyl Group ◽

Lone Pair ◽

The Other ◽

Tetrahedral Intermediate ◽

Hydrolysis Products ◽

Anti Conformation ◽

Stereoelectronic Control ◽

Basic Hydrolysis ◽

Hydrolysis Of ◽

Nitrogen Bond

A new stereoelectronic theory for the cleavage of the tetrahedral intermediate (hemiorthoamide) in the hydrolysis of amides is presented. In this new theory, the precise conformation of the tetrahedral intermediate controls the nature of the hydrolysis products. It is postulated that the breakdown of the tetrahedral intermediate depends upon the orientation of the lone pair orbitals of the heteroatoms. Specific cleavage of a carbon–oxygen or a carbon–nitrogen bond in any conformer is allowed only if the other heteroatoms (oxygen and nitrogen) each have an orbital oriented antiperiplanar to the leaving O-alkyl or N-alkyl group. Experimentally, a study of the basic hydrolysis of a variety of N,N-dialkylated imidate salts having either a syn or an anti conformation demonstrates clearly that there is a stereoelectronic control in the cleavage of the hemiorthoamide.

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Facile synthesis and biological activity of sulfonate ester-containing imidazolylpyridine, imidazo(4,5-b)pyridine and imidazo(5',1':2,3)imidazo(4,5-b)pyridine derivatives

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19891096 ◽

1989 ◽

Vol 54 (4) ◽

pp. 1096-1103 ◽

Cited By ~ 8

Author(s):

Margret Mansour Girges ◽

Mohamed Mahmoud Abou El-Zahab ◽

Mokhtar Ayad Hanna

Keyword(s):

Antimicrobial Activity ◽

Biological Activity ◽

Elemental Analysis ◽

Ring Opening ◽

Pyridine Derivatives ◽

Facile Synthesis ◽

Reaction Conditions ◽

Ester Moiety ◽

Synthetic Routes ◽

Sulfonate Ester

Different ring systems containing imidazole and/or pyridine moieties and accomodating sulfonate ester moiety in their structure were prepared via ring opening of 2-oxazolin-5-one derivatives under various reaction conditions. The assigned structures for the prepared compounds were established through elemental analysis, spectral data and if possible by alternative synthetic routes. The antimicrobial activity of the synthesized compounds was also investigated.

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Basic hydrolysis of carbamate to amine in aqueous ethanol

ChemSpider Synthetic Pages ◽

10.1039/sp734 ◽

2014 ◽

Author(s):

John MacMillan

Keyword(s):

Aqueous Ethanol ◽

Basic Hydrolysis ◽

Hydrolysis Of

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Effect of C6-Volatiles on Bioluminescent Plant Pathogens

HortScience ◽

10.21273/hortsci.33.3.557d ◽

1998 ◽

Vol 33 (3) ◽

pp. 557d-557

Author(s):

Jennifer Warr ◽

Fenny Dane ◽

Bob Ebel

Keyword(s):

Biological Activity ◽

Bacterial Growth ◽

Xanthomonas Campestris ◽

Plant Pathogens ◽

Genetically Engineered ◽

The Other ◽

Computer Assisted ◽

Signal Molecules ◽

Low Concentrations

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.

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The Psychonauts’ Benzodiazepines; Quantitative Structure-Activity Relationship (QSAR) Analysis and Docking Prediction of Their Biological Activity

Pharmaceuticals ◽

10.3390/ph14080720 ◽

2021 ◽

Vol 14 (8) ◽

pp. 720

Author(s):

Valeria Catalani ◽

Michelle Botha ◽

John Martin Corkery ◽

Amira Guirguis ◽

Alessandro Vento ◽

...

Keyword(s):

Biological Activity ◽

Computational Models ◽

Quantitative Structure Activity Relationship ◽

Structure Activity Relationship ◽

Docking Studies ◽

Health Concern ◽

Activity Relationship ◽

Quantitative Structure ◽

High Biological Activity ◽

Structure Activity

Designer benzodiazepines (DBZDs) represent a serious health concern and are increasingly reported in polydrug consumption-related fatalities. When new DBZDs are identified, very limited information is available on their pharmacodynamics. Here, computational models (i.e., quantitative structure-activity relationship/QSAR and Molecular Docking) were used to analyse DBZDs identified online by an automated web crawler (NPSfinder®) and to predict their possible activity/affinity on the gamma-aminobutyric acid A receptors (GABA-ARs). The computational software MOE was used to calculate 2D QSAR models, perform docking studies on crystallised GABA-A receptors (6HUO, 6HUP) and generate pharmacophore queries from the docking conformational results. 101 DBZDs were identified online by NPSfinder®. The validated QSAR model predicted high biological activity values for 41% of these DBDZs. These predictions were supported by the docking studies (good binding affinity) and the pharmacophore modelling confirmed the importance of the presence and location of hydrophobic and polar functions identified by QSAR. This study confirms once again the importance of web-based analysis in the assessment of drug scenarios (DBZDs), and how computational models could be used to acquire fast and reliable information on biological activity for index novel DBZDs, as preliminary data for further investigations.

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Replacement of the interchain disulfide bridge-forming amino acids A7 and B7 by glutamate impairs the structure and activity of insulin

Biological Chemistry ◽

10.1515/bc.2004.151 ◽

2004 ◽

Vol 385 (12) ◽

pp. 1171-1175 ◽

Cited By ~ 7

Author(s):

Zhan-Yun Guo ◽

Xiao-Yuan Jia ◽

You-Min Feng

Keyword(s):

Biological Activity ◽

Disulfide Bonds ◽

Negative Charge ◽

Disulfide Bridge ◽

Site Directed Mutagenesis ◽

Side Chain ◽

Insulin Analogs ◽

High Biological Activity ◽

Chemical Groups ◽

Structure And Activity

Abstract Insulin contains three disulfide bonds, one intrachain bond, A6–A11, and two interchain bonds, A7–B7 and A20–B19. Site-directed mutagenesis results (the two cysteine residues of disulfide A7–B7 were replaced by serine) showed that disulfide A7–B7 is crucial to both the structure and activity of insulin. However, chemical modification results showed that the insulin analogs still retained relatively high biological activity when A7Cys and B7Cys were modified by chemical groups with a negative charge. Did the negative charge of the modification groups restore the loss of activity and/or the disturbance of structure of these insulin analogs caused by deletion of disulfide A7–B7? To answer this question, an insulin analog with both A7Cys and B7Cys replaced by Glu, which has a long side-chain and a negative charge, was prepared by protein engineering, and its structure and activity were analyzed. Both the structure and activity of the present analog are very similar to that of the mutant with disulfide A7–B7 replaced by Ser, but significantly different from that of wild-type insulin. The present results suggest that removal of disulfide A7–B7 will result in serious loss of biological activity and the native conformation of insulin, even if the disulfide is replaced by residues with a negative charge.

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