Unreferenced stub auto yes date December 2009 Chembox verifiedrevid 408972818 ImageFileL1 Pyridinium.svg ImageSizeL1 80px ImageFileR1 Pyridinium 3D balls.png ImageSizeR1 120px IUPACName pyridinium OtherNames Section1 Chembox Identifiers InChI 1S C5H5N c1 2 4 6 5 3 1 h1 5H p 1 InChIKey1 JUJWROOIHBZHMG UHFFFAOYSA O InChI1 1S C5H5N c1 2 4 6 5 3 1 h1 5H p 1 CASNo 16969 45 2 CASNo Ref cascite correct CAS PubChem 4989215 ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 4169387 SMILES nH 1ccccc1 StdInChI Ref stdinchicite correct chemspider StdInChI 1S C5H5N c1 2 4 6 5 3 1 h1 5H p 1 Section2 Chembox Properties C 5 H 6 N 1 Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Pyridinium refers to the cationic form of pyridine . This can either be due to protonation of the ring nitrogen or because of addition of a substituent to the ring nitrogen, typically via alkylation . The lone pair of electron s on the nitrogen atom of pyridine is not delocalized , and thus pyridine can be protonated easily. Pyridine is often used as an organic base in chemical reactions, thus the pyridinium ion is produced as the counter ion to the leaving group in the reaction. This complex is often insoluble in the organic solvent, so precipitation of the pyridinium leaving group complex is an indication of the progress of the reaction. The pyridinium ion also plays a role in Friedel Crafts acylation . When pyridine is included, it forms a complex with the electrophillic acylium ion, rendering it even more reactive. See also Pyridinium chlorochromate Category Pyridines Organic compound stub fr Ion pyridinium nl Pyridinium ... more details
chembox verifiedrevid 406365741 Name Pyridinium chlorochromate ImageFile Pyridinium chlorochromate.PNG ImageSize 150px ImageName Chemical structure of the Pyridinium Chlorochromate ImageFileL1 Pyridinium 3D balls.png ImageNameR1 Ball and stick model of the pyridinium cation ImageFileR1 Chlorochromate 3D balls.png ImageNameR1 Ball and stick model of the chlorochromate anion IUPACName Pyridinium chlorochromate OtherNames PCC Section1 Chembox Identifiers InChI 1 C5H5N.ClH.Cr.3O c1 2 4 6 5 3 1 h1 5H 1H q 1 1 rC5H5N.ClCrO3 c1 2 4 6 5 3 1 1 2 3,4 5 h1 5H q 1 p 1 InChIKey LEHBURLTIWGHEM YOEUSAHMAN CASNo 26299 14 9 ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 10608386 SMILES O Cr O O Cl. nH 1ccccc1 StdInChI Ref stdinchicite correct chemspider StdInChI 1S C5H5N.ClH.Cr.3O c1 2 4 6 5 3 1 h1 5H 1H q 1 1 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey LEHBURLTIWGHEM UHFFFAOYSA N Section2 Chembox Properties Formula C sub 5 sub H sub 5 sub NHClCrO sub 3 sub MolarMass 215.56 g mol Appearance orange crystalline powder MeltingPt 205 C Solvent other solvents SolubleOther soluble in dichloromethane , br benzene , diethyl ether , br acetone , acetonitrile , br THF Section7 ... 53 45 60 61 Pyridinium chlorochromate is a reddish orange solid reagent used to oxidize primary alcohols to aldehydes and secondary alcohols to ketones . Pyridinium chlorochromate, or PCC , will not fully ... name corey cite journal author Corey, E.J. Suggs, W. title Pyridinium Chlorochromate. An Efficient ... Lett. year 1975 volume 16 pages 2647 2650 doi 10.1016 S0040 4039 00 75204 X ref Pyridinium dichromate ... author Agarwal, S Tiwari, H. P. Sharma, J. P. title Pyridinium Chlorochromate an Improved Method ... Chromium VI oxide is treated with pyridine pyridinium chloride C sub 5 sub H sub 5 sub NH sup sup ... http www.chemicalland21.com arokorhi lifescience phar PYRIDINIUM 20DICHROMATE.htm Datasheet PDC http ... ca Clorocromat de piridini de Pyridiniumchlorochromat fr Chlorochromate de pyridinium ja ... more details
orphan date May 2010 unref date December 2010 Poly pyridinium salt s are members of a class of main chain polyelectrolyte s. DEFAULTSORT Poly Pyridinium Salt S Category Polyelectrolytes Category Organic polymers Polymer stub ... more details
PPTS may refer to Palestine Pilgrims Text Society , a Victorian academic society Pulsed plasma thruster s, a type of spacecraft propulsion Prospective Piloted Transport System , a Russian spacecraft Pyridinium p toluenesulfonate , a chemical reagent See also Power point disambiguation disambig ja PPTS ... more details
Collins reagent is the complex of chromium trioxide chromium VI oxide with pyridine in dichloromethane . ref cite journal title Dipyridine chromium VI oxide oxidation of alcohols in dichloromethane author J. C. Collins, W. W. Hess and F. J. Frank journal Tetrahedron Lett. year 1968 volume 9 issue 30 pages 3363 3366 doi 10.1016 S0040 4039 00 89494 0 ref ref OrgSynth author J. C. Collins, W.W. Hess title Aldehydes from Primary Alcohols by Oxidation with Chromium Trioxide Heptanal collvol 6 collvolpages 644 prep cv6p0644 year 1988 ref It is used to selectively alcohol oxidation oxidize primary alcohol s to the aldehyde , and will tolerate many other functional group s within the molecule. Image Collins reagent.png center 300px It can be used as an alternative to the Jones reagent and pyridinium chlorochromate PCC when oxidising secondary alcohols to ketone s. Moreover, the Collins reagent is especially useful for oxidations of acid sensitive compounds. This complex is both difficult and dangerous to prepare, as it is very hygroscopic and can inflame during preparation. It is typically used in a sixfold excess in order to complete the reaction. Nowadays, PCC or PDC oxidation have largely supplanted Collins oxidation for these very reasons. chemistry stub See also Jones oxidation Pyridinium chlorochromate Pyridinium dichromate Sarett oxidation References references Category Oxidizing agents Category Chromium compounds de Collins Reagenz fr R actif de Collins pt Reagente de Collins es Reactivo de Collins ... more details
and functions it is closely related to other compounds made from hexavalent chromium oxide, such as pyridinium ... to the presence of pyridinium cations. The Cornforth reagent is readily soluble in water, dimethylformamide ... Useful procedures for the oxidation of alcohols involving pyridinium dichromate in approtic media ... capability. Among organic acids, acetic acid , pyridinium Trifluoroacetic acid trifluoroacetate or pyridinium tosyl ate can be added, the first one being most efficient and easiest to remove. The achieved ... and functions, the Cornforth reagent is closely related to other pyridinium salts of hexavalent chromium oxide, such as pyridinium chlorochromate PyH CrO sub 3 sub Cl and to pyridine complexes such as the Collins ... on the country. As a strong oxidant, pyridinium dichromate promotes fires, releasing carbon monoxide ... more details
The Zincke reaction is an organic reaction in which a pyridine is transformed into a pyridinium salt by reaction with 2,4 dinitro chlorobenzene and a primary amine , named after Theodor Zincke . ref cite journal title Ueber Dinitrophenylpyridiniumchlorid und dessen Umwandlungsproducte author Theodor Zincke Zincke, Th. Heuser, G. Moller, W. journal Justus Liebigs Annalen der Chemie volume 333 issue 2 3 pages 296 345 year 1904 url doi 10.1002 jlac.19043330212 ref ref cite journal title Ueber Dinitrophenylpyridiniumchlorid und dessen Umwandlungsproducte author Theodor Zincke Zincke, Th. Heuser, G. Moller, W. journal Justus Liebigs Annalen der Chemie volume 330 issue 2 pages 361 374 year 1904 url doi 10.1002 jlac.19043300217 ref ref cite journal title ber Dinitrophenylisochinoliniumchlorid und dessen Umwandlungsprodukte author Zincke, T. H. Weisspfenning, G. journal Justus Liebigs Annalen der Chemie volume 396 issue 1 pages 103 131 year 1913 url doi 10.1002 jlac.19133960107 ref Image ZinckeReaction.png 500px center The Zincke reaction The Zincke reaction should not be confused with the Zincke ... pyridinium salt 2 . This salt is typically isolated and purified by recrystallization chemistry ... pyridinium salt Upon heating a primary amine with the N 2,4 dinitrophenyl pyridinium salt 2 , the addition of the amine leads to the opening of the pyridinium ring. A second addition of amine leads ... reaction elimination , the desired pyridinium ion 9 is formed. Image Zincke Reaction Mechanism2.png ... is covalently attached to Wang resin . ref The Solid Phase Zincke Reaction Preparation of Hydroxy Pyridinium ... Heterocycles by the Ring Opening of Pyridinium Salts Aaron M. Kearney, Christopher D. Vanderwal Angew ... annulene structure 1 from an N aryl pyridinium chloride and an amine , an aniline in the case of the Japanese ... annulene Derivatives? 100 Year Old Pyridinium Salts p 9152 9153 Manfred Christl Published Online Nov ... was not the 12 membered ring but the 6 membered pyridinium salt structure 2 . Initially both groups ... more details
Unreferenced date December 2009 In chemistry, hydrochlorides are salt chemistry salt s resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic Base chemistry base mostly amine s . This is also known as muriate , derived from hydrochloric acid s other name muriatic acid. For example, reaction of pyridine C sub 5 sub H sub 5 sub N with hydrochloric acid HCl yields pyridine hydrochloride C sub 5 sub H sub 5 sub N HCl . Even though this style of formula is often used for denoting the hydrochlorides, the dot incorrectly implies that the two molecules are weakly bonded together rather, what is present is the salt C sub 5 sub H sub 5 sub NH sup sup Cl sup sup with the correct chemical name pyridinium pyridinium chloride . Hydrochloric salts are most often referred to by using the name of the base, then simply tagging on hydrochloride or HCl . For example, while crack cocaine is the Free base chemistry freebase of cocaine, the salt form is often referred to as cocaine HCl. Uses Converting insoluble amines into hydrochlorides is a common way to make them Solubility water and acid soluble . This is particularly desirable for substances used in medications. Many pharmaceutical substances are prepared as hydrochlorides so that they may be quickly released in the gastrointestinal tract the body usually absorbs a hydrochloride within fifteen or thirty minutes. Very often hydrochlorides of amines have longer shelf lives than their respective free bases. Examples of hydrochlorides in medical uses are many, ranging from over the counter drug over the counter sinus relief to antidepressants . See also Free base chemistry Quaternary ammonium cation Category Organochlorides Category Salts de Hydrochlorid fr Chlorhydrate it Cloridrato nl Waterstofchloride pl chlorowodorki pt Cloridrato sv Hydroklorid zh ... more details
and Heat Benzylation of Alcohols Using a Bench Stable Pyridinium Salt year 2006 journal J. Org. Chem. volume 71 issue 10 pages 3923 3927 doi 10.1021 jo0602773 pmid 16674068 ref employs a benzyloxy pyridinium salt as a benzyl transfer reagent for alcohols Image Pyridinium salt benzyl ether protection.png 600px Pyridinium salt benzyl ether protection Trifluorotoluene was used as the solvent in the presence ... more details
The Sarett oxidation is the oxidation of an alcohol to a ketone or an aldehyde using chromium trioxide and pyridine . Primary alcohol s will only be oxidised to the aldehyde and not on to carboxylic acid s. Image sarett.png The reagent is named after the American chemist Lewis Hastings Sarett 1917 1999 . See also Collins reagent Pyridinium chlorochromate Jones oxidation References cite journal title Approaches to the Total Synthesis of Adrenal Steroids.1 V. 4b Methyl 7 ethylenedioxy 1,2,3,4,4a ,4b,5,6,7,8,10,10a dodecahydrophenanthrene 4 ol 1 one and Related Tricyclic Derivatives author G. I. Poos, G. E. Arth, R. E. Beyler, and L. H. Sarett journal Journal of the American Chemical Society volume 75 issue 2 pages 422 429 year 1953 url doi 10.1021 ja01098a049 J. R. Holum, J. Org. Chem. 26, 4814 1961 E. J. Kris, Chemistry & Industry London 1961 1834 V. I. Stenberg, and R. J. Perkins, J. Org. Chems. 28, 323 1963 P. G. Gassman and P. G. Pape, J. Org. Chem. 29, 160 1964 . External links http www.chempensoftware.com reactions RXN348.htm Sarett oxidation Category Organic redox reactions Reaction stub Category Name reactions fr Oxydation de Sarett zh ... more details
Drugbox IUPAC name 4 carbamoyl 1 2 E hydroxyimino methyl pyridinium 1 yl methoxy methyl pyridinium dichloride image Asoxime chloride.svg CAS number 34433 31 3 ATC prefix ATC suffix PubChem 5484128 DrugBank ChemSpiderID 13004322 chemical formula C sub 14 sub H sub 16 sub N sub 4 sub O sub 3 sub · 2Cl sup &minus sup molecular weight 359.21 g mol bioavailability protein bound metabolism elimination half life excretion pregnancy AU A B1 B2 B3 C D X pregnancy US A B C D X pregnancy category legal AU S2, S3, S4, S5, S6, S7, S8, S9 or Unscheduled legal CA Schedule I, II, III, IV, V, VI, VII, VIII legal UK GSL, P, POM, CD, or Class A, B, C legal US OTC Rx only Schedule I, II, III, IV, V legal status Experimental routes of administration Intramuscular injection Asoxime chloride , or more commonly HI 6 , is a oxime Hagedorn oxime used in the treatment of organophosphate poisoning . pharma stub Antidotes Category Antidotes Category Oximes pl Azoksym ... more details
Drugbox IUPAC name 1,1&prime propane 1,3 diylbis 4 E hydroxyimino methyl pyridinium dibromide image Trimedoxime bromide structure.svg width 250 CAS number 56 97 3 ATC prefix None ATC suffix PubChem 5359236 DrugBank ChemSpiderID 4514238 chemical formula C sub 15 sub H sub 18 sub N sub 4 sub O sub 2 sub · 2Br sup &minus sup molecular weight 446.14 g mol bioavailability protein bound metabolism elimination half life 2 hours mean excretion pregnancy AU A B1 B2 B3 C D X pregnancy US A B C D X pregnancy category legal AU S2, S3, S4, S5, S6, S7, S8, S9 or Unscheduled legal CA Schedule I, II, III, IV, V, VI, VII, VIII legal UK GSL, P, POM, CD, or Class A, B, C legal US OTC Rx only Schedule I, II, III, IV, V legal status Experimental br In military use routes of administration Intramuscular injection Trimedoxime bromide International Nonproprietary Name INN , also known as dipyroxime or TMB 4 , is an oxime used in the treatment of organophosphate poisoning . pharma stub Antidotes Category Antidotes Category Oximes ... more details
Refimprove date July 2009 drugbox verifiedrevid 400334483 IUPAC name 1,1 oxybis methylene bis 4 E br hydroxyimino methyl pyridinium image Obidoxime skeletal.svg ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 4588647 InChI 1 C14H14N4O3 c19 15 9 13 1 5 17 6 2 13 11 21 12 18 7 3 14 4 8 18 10 16 20 h1 10H,11 12H2 p 2 InChIKey HIGRLDNHDGYWQJ SKRXCDHZAW smiles O NH C C1 C C N C C1 COCN 2 C C C C C 2 C NH O StdInChI Ref stdinchicite correct chemspider StdInChI 1S C14H14N4O3 c19 15 9 13 1 5 17 6 2 13 11 21 12 18 7 3 14 4 8 18 10 16 20 h1 10H,11 12H2 p 2 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey HIGRLDNHDGYWQJ UHFFFAOYSA P CAS number 114 90 9 ATC prefix V03 ATC suffix AB13 PubChem 5485192 DrugBank C 14 H 16 N 4 O 3 charge 2 molecular weight 288.302 g mol bioavailability protein bound metabolism elimination half life excretion Kidney Renal pregnancy AU A B1 B2 B3 C D X pregnancy US A B C D X pregnancy category legal AU Unscheduled S2 S3 S4 S5 S6 S7 S8 S9 legal CA Schedule I, II, III, IV, V, VI, VII, VIII legal UK GSL P POM CD Class A, B, C legal US OTC Rx only Schedule I, II, III, IV, V legal status routes of administration Obidoxime is a member of the oxime family used to treat nerve gas poisoning. Oximes are drugs known for their ability to reverse the binding of organophosphorus compounds to the enzyme acetylcholinesterase AChE . ref name pmid19519385 cite journal author Jokanovi M, Prostran M title Pyridinium oximes as cholinesterase reactivators. Structure activity relationship and efficacy in the treatment of poisoning with organophosphorus compounds journal Curr. Med. Chem. volume 16 issue 17 pages 2177 88 year 2009 pmid 19519385 doi 10.2174 092986709788612729 url http www.bentham direct.org pages content.php?CMC 2009 00000016 00000017 0004C.SGM ref AChE is an enzyme that removes acetylcholine from the synapse after it creates the required stimulation on the next nerve cell . If it gets inhibited, acetylcholine is not removed after t ... more details
Image E1cB.gif right frame The E1cB reaction mechanism. The E1cB elimination reaction is a special type of elimination reaction in organic chemistry . This reaction mechanism explains the formation of alkene s from mostly alkyl halide s through a carbanion intermediate given specified reaction conditions and specified substrates. The abbreviation stands for E limination U nimolecular c onjugate B ase. The reaction takes place around a orbital hybridization sp sup 3 sup sp sup 3 sup carbon to carbon covalent bond with an acidic hydrogen atom substituent and a leaving group . This leaving group can be a halide or a sulfonic acid ester such as a tosyl group. A strong base chemistry base abstracts the proton generating a carbanion . The electron pair then expels the leaving group and the double bond is formed. When the first step to the carbanion is slow and the second step fast the reaction is irreversible and named E1cB sub i sub . When the first step is fast and the deprotonation reversible then the reaction mechanism is E1cB sub r sub . In the E1cB sub anion sub variation the carbanion is especially stable with a rapid first step and a slow second step. Image E1cBexample.gif right frame The E1cB reaction mechanism. Reaction of 1 methyl 2 2 fluoroethyl pyridinium iodide with hydroxide. A named reaction displaying E1cB elimination mechanism is the Boord olefin synthesis . Being able to distinguish between different elimination reaction mechanisms E2, E1, E1cB is often difficult and involves the study of chemical kinetics , kinetic isotope effect s, substituent effects and computational chemistry . The reaction of 1 methyl 2 2 fluoroethyl pyridinium iodide with the hydroxide ion in water is an example of a 2 step E1cB reaction because the carbanion is stabilized by the resonance effect with the enamine . ref cite journal title Evidence of a Borderline Region between E1cb and E2 Elimination Reaction Mechanisms A Combined Experimental and Theoretical Study of Syste ... more details
Unreferenced date November 2006 Chembox verifiedrevid 399891783 ImageFile Desmosine.PNG ImageSize IUPACName 4 4 amino 4 carboxybutyl 1 5 amino 5 carboxypentyl 3,5 bis 3 amino 3 carboxypropyl pyridinium OtherNames Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 23745 InChI 1 C24H39N5O8 c25 17 21 30 31 5 1 2 11 29 12 14 7 9 19 27 23 34 35 16 4 3 6 18 26 22 32 33 15 13 29 8 10 20 28 24 36 37 h12 13,17 20H,1 11,25 28H2, H3 ,30,31,32,33,34,35,36,37 p 1 InChIKey VEVRNHHLCPGNDU IKLDFBCSAT StdInChI Ref stdinchicite correct chemspider StdInChI 1S C24H39N5O8 c25 17 21 30 31 5 1 2 11 29 12 14 7 9 19 27 23 34 35 16 4 3 6 18 26 22 32 33 15 13 29 8 10 20 28 24 36 37 h12 13,17 20H,1 11,25 28H2, H3 ,30,31,32,33,34,35,36,37 p 1 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey VEVRNHHLCPGNDU UHFFFAOYSA O CASNo 11003 57 9 PubChem 25435 SMILES O C O C N CCCC n 1cc c c c1 CCC C O O N CCCC C O O N CCC C O O N Section2 Chembox Properties C 24 H 40 N 5 O 8 Formula MolarMass Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition A desmosine cross link is formed from three allysyl side chains plus one unaltered lysyl side chain from the same or neighbouring polypeptides . It is found in elastin . Desmosine causes a yellow color. This desmosine is responsible for the rubber properties of elastin. Protein primary structure Category Proteins Category Peptides Protein stub de Desmosin fr Desmosine it Desmosina ja ru zh ... more details
Picoline refers to three different methyl pyridine isomerism isomers , all with the chemical formula carbon C sub 6 sub hydrogen H sub 7 sub nitrogen N and a molar mass of 93.13 g mol sup 1 sup . All three are colourless liquids at room temperature and pressure and are miscible with water and most organic solvents. Data for the three compounds are summarized in the table. class wikitable class sortable wikitable Name s CAS m.p. C b.p. C p K sub a sub of pyridinium ion structure 2 Methylpyridine , picoline 109 06 8 66.7 129.4 5.96 Image 2 methylpyridine 2D skeletal.png 70px center picoline center 3 Methylpyridine , picoline 108 99 6 18 141 5.63 Image 3 methylpyridine 2D skeletal.png 70px center picoline center 4 Methylpyridine , picoline 108 89 4 3.6 145.4 5.98 Image 4 methylpyridine 2D skeletal.png 50px center picoline center The CAS registry number CAS number of an unspecified picoline isomer is 1333 41 1 Environmental properties Picolines exhibit greater volatility and are more slowly degraded than their carboxylic acid counterparts. Volatilization is much less extensive in soil than water, owing to sorption of the compounds to soil clays and organic matter. ref Sims, G. K. and L.E. Sommers. 1985. Degradation of pyridine derivatives in soil. J. Environmental Quality. 14 580 584. ref Picoline degradation appears to be mediated primarily by bacteria, with the majority of isolates belonging to the Actinobacteria. 3 Methylpyridine degrades more slowly than the other two isomers, likely due to the impact of resonance in the heterocyclic ring. Like most simple pyridine derivatives, the picolines contain more nitrogen than is needed for growth of microorganisms, and excess nitrogen is generally excreted to the environment as ammonium during the degradation process. ref Sims, G. K. and L.E. Sommers. 1986. Biodegradation of pyridine derivatives in soil suspensions. Environmental Toxicology and Chemistry. 5 503 509. ref References Reflist Category Pyridines de P ... more details
chembox ImageFile MPP .svg ImageSize 200px IUPACName 1 Methyl 4 phenylpyridin 1 ium OtherNames Cyperquat Section1 Chembox Identifiers CASNo 39794 99 5 PubChem 39484 EINECS 248 939 7 ChEMBL Ref ebicite correct EBI ChEMBL 311617 SMILES C n 1 cc c c c1 c2 cc cc c2 MeSHName 1 Methyl 4 phenylpyridinium Section2 Chembox Properties Formula C sub 12 sub H sub 12 sub N sup sup MolarMass 170.25 g mol Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition MPP 1 methyl 4 phenyl pyridine pyridinium is a positively charged molecule with chemical formula Carbon C sub 12 sub Hydrogen H sub 12 sub Nitrogen N sup sup . It is toxicity toxic and acts by interfering with oxidative phosphorylation in mitochondria , causing depletion of adenosine triphosphate ATP and cell death . ref name pubchem http pubchem.ncbi.nlm.nih.gov summary summary.cgi?cid 39484 PubChem Compound entry on MPP ref It also inhibits the synthesis of catecholamine s, reduces levels of dopamine and heart cardiac norepinephrine , and inactivates tyrosine hydroxylase . ref name pubchem The neurotoxin MPTP is converted in the brain into MPP by the enzyme MAO B , causing parkinsonism in primate s by killing certain dopamine producing neurons in the substantia nigra . The chloride of MPP has been used as a herbicide under the trade name cyperquat and is structurally similar to the herbicide paraquat . References Reflist 2 Neurotoxins Herbicides Dopaminergics Category Herbicides Category Neurotoxins Category Pyridines Category Quaternary ammonium compounds fr MPP it MPP pharmacology stub ... more details
Amorphous silica alumina is a synthetic substance that is used as a catalyst or catalyst support. ref name Scherzer Julius Scherzer, Adrian J. Gruia, 1996 , Hydrocracking Science and Technology , CRC Press, ISBN 082479760 ref It can be prepared in a number of ways for example ref name Scherzer Precipitation of hydrous alumina onto amorphous silica hydrogel Reacting a silica sol with an alumina sol Coprecipitation from sodium silicate aluminium salt solution Water soluble contaminants e.g. sodium salts are removed by washing. ref name Scherzer br Some of the alumina is present in tetrahedral coordination as shown by NMR studies sup 29 sup Si Magic angle spinning MAS solid state NMR NMR and sup 27 sup Al solid state NMR NMR ref Nuclear magnetic resonance study of the dealumination of an amorphous silica alumina catalyst,Pascal P. Man, Marie Jeanne Peltre and Denise Barthomeuf, J. Chem. Soc., Faraday Trans., 1990, 86, 1599 1602, doi 10.1039 FT9908601599 ref br Amorphous silica alumina contains sites which are termed Br nsted acid or protic sites,with an ionizable hydrogen atom, and Lewis acid aprotic , electron accepting sites and these different types of acidic site can be distinguished by the ways in which, say, pyridine attaches. On Lewis acid sites it forms complexes and on the Br nsted sites it adsorbs as the pyridinium ion. ref Dale L. Perry, 1992, Applications of Analytical Techniques to the Characterization of Materials proceedings of a symposium on applications of analytical techniques to the characterization of materials, held August 29 30, 1990, American Chemical Society Division of Industrial and Engineering Chemistry, Dale L. Perry, Springer, ISBN 0306441896 ref Examples of processes that use silica alumina catalysts are the production of pyridine from crotonaldehyde , formaldehyde , steam, air and ammonia ref John Arthur Joule, Keith Mills, 2000,Heterocyclic Chemistry,4th edition, Blackwell Publishing,ISBN 0632054530 ref and the cracking of hydrocarbons, ... more details
PDC may refer to TOCright Chemistry Pyruvate decarboxylase , a homotetrameric enzyme that catalyses the decarboxylation of pyruvic acid to acetaldehyde and carbon dioxide Pyruvate dehydrogenase complex , a complex of three enzymes that transform pyruvate into acetyl CoA Cornforth reagent Pyridinium dichromate , a chromium based oxidant used in organic chemistry Computing Professional Developers Conference , a Microsoft conference for software developers Pocket Dream Console , a small handheld game device created by Tomy and Conny in 2006 Personal Digital Cellular , a 2G mobile phone standard developed and used exclusively in Japan Programme Delivery Control , a standard to control video recorders using hidden codes in the teletext service Plugin Delay Compensation , a technique for keeping the output of digital audio effects synchronized when each may introduce delay into the signal Practical Devices Corporation , manufacturer of high end headphone amplifiers Primary Domain Controller , a server computer in a pre Windows 2000 NT server Domain Peripheral DMA controller , A feature of microcontrollers automating internal feeds for data streams Education California State University, San Bernardino Palm Desert Campus General Science Parktronic Parking Distance Control , is a system used in BMW cars to measure the distance between the car and obstacles Polycrystalline Diamond Compact drill bits Pulsed DC , the form of wave produced from a half wave rectifier or a full wave rectifier Pyroclastic flow Pyroclastic density current , a highly energetic ground current of superheated gases containing a high density of suspended pyroclastic fragments resulting from a volcanic explosion Politics and government Christian Democratic People s Party of Switzerland , a political party in Switzerland Several parties called Partido Dem crata Cristiano Christian Democratic Party Brazil Partido Democrata Crist o Portland Development Commission , Portland, Oregon government agency Linguist ... more details
PCC may stand for Biology and Chemistry PCC Coating , pyrolytic chromium carbide coating by vacuum deposition Precipitated calcium carbonate Propionyl CoA carboxylase Pyridinium chlorochromate Medicine Pheochromocytoma , a neuroendocrine tumor Organizations and companies Partido Comunista de Canarias, the Communist Party of the Canaries Partido Comunista de Cuba, the Cuban Communist Party Partido Comunista Colombiano, the Colombian Communist Party Pacific Coast Conference , a defunct United States college athletic conference The Pacific Conference of Churches , the regional ecumenical organization in the Pacific region Palestinian cultural club Palestinian Conciliation Commission Panama Canal Commission Partit dels i les Comunistes de Catalunya Perth City Council People s Computer Company Clef Club of Jazz and Performing Arts Plainfield Curling Club Plains Conservation Center Polynesian Cultural Center Power Computing Corporation Porirua Porirua City Council Power Corporation of Canada Pradesh Congress Committee , the provincial committee of the Congress Party in India Precision Castparts Corp. in Portland, Oregon Presbyterian Church in Canada Prerogative Court of Canterbury an important English court for probate Press Complaints Commission Printed Circuit Corporation Primeiro Comando da Capital , a Brazilian prison gang terrorist group PCC FoliaConcept , the largest design company in Northern Germany PCC Natural Markets , Puget Consumer s Co op Photo Card Caf , a greeting card company Colleges Pabna Cadet College Palmer College of Chiropractic Pasadena City College Pensacola Christian College Piedmont Community College Pitt Community College Pima Community College Polk State College , formerly Polk Community College Portland Community College Presentation College Chaguanas Punjab College of Commerce Penola Catholic College Governmental groups Parochial Church Council Patents County Court Poison control center Other uses PCC streetcar Parochial church council Passp ... more details
Unreferenced date December 2009 Orphan date December 2009 border 0 cellpadding 5 cellspacing 0 style margin 1em float right class wikitable colspan 3 Basic aromatic ring systems align center valign bottom Image Pyridine structure.png 67px br Pyridine Image Quinoline structure.png 119px br Quinoline Image Isoquinoline structure.png 126px br Isoquinoline align center valign bottom Image Acridine structure.png 171px br Acridine align center valign bottom Image Pyrazine structure.png 67px br Pyrazine Image Quinoxaline structure.png 119px br Quinoxaline align center valign bottom Image Imidazole structure.png 63px br Imidazole Image Benzimidazole structure.png 113px br Benzimidazole Image Purine structure.png 113px br Purine align center valign bottom Image Pyrazole structure.png 70px br Pyrazole Image Indazole structure.png 120px br Indazole align center valign bottom Image Pyrimidine structure.png 74px br Pyrimidine Image Quinazoline structure.png 126px br Quinazoline align center valign bottom Image Pyridazine structure.png 74px br Pyridazine Image Cinnoline structure.png 126px br Cinnoline Basic aromatic rings are simple aromatic ring aromatic rings in which the lone pair of electron s of a ring nitrogen atom is not part of the aromatic system and extends in the plane of the ring. This lone pair is responsible for the Base chemistry basicity of these nitrogenous base s, similar to the nitrogen atom in amine s. In these compounds the nitrogen atom is not connected to a hydrogen atom. Basic aromatic compounds get Protonation protonated and form aromatic cation s e.g. pyridinium under acid ic conditions. Typical examples of basic aromatic rings are pyridine or quinoline . Several rings contain basic as well as non basic nitrogen atoms, e.g. imidazole and purine . In non basic aromatic rings the lone pair of electron s of the nitrogen atom is delocalized and contributes to the aromatic pi electron system. In these compounds the nitrogen atom is connected to a hydrogen at ... more details
carcinoma. PDC in DMF Corey and Schmidt Main pyridinium dichromate Pyridinium dichromate PDC is a bright ... 01 93515 4 title Useful procedures for the oxidation of alcohols involving pyridinium dichromate in approtic ... more details
The Baker Nathan effect in organic chemistry is an effect observed with reaction rate s for certain chemical reaction s with certain substrates where the order in reactivity cannot be explained solely by an inductive effect of substituents. ref HYPERCONJUGATION INTERMEDIATES AND TRANSITION STATES IN REPLACEMENT AND ELIMINATION Peter B.D. de la Mare Pure & Appl. Chem., Vol 56, No. 12, pp 755 1766, 1984 http www.iupac.org publications pac 1984 pdf 5612x1755.pdf ref This effect was described in 1935 by John W. Baker and W. S. Nathan. ref 118. The mechanism of aromatic side chain reactions with special reference to the polar effects of substituents. Part III. The effect of unipolar substituents on the critical energy and probability factors in the interaction of benzyl bromide with pyridine and picoline in various solvents John W. Baker and W. S. Nathan J. Chem. Soc. , 1935 , 519 527, DOI 10.1039 JR9350000519 ref ref 428. The mechanism of aromatic side chain reactions with special reference to the polar effects of substituents. Part IV. The mechanism of quaternary salt formation John W. Baker, Wilfred S. Nathan, J. Chem. Soc. , 1935 , 1840 1844 DOI 10.1039 JR9350001840 ref ref 429. The mechanism of aromatic side chain reactions with special reference to the polar effects of substituents. Part V. The polar effects of alkyl groups John W. Baker, Wilfred S. Nathan, J. Chem. Soc. , 1935 , 1844 1847 DOI 10.1039 JR9350001844 ref They examined the chemical kinetics for the reaction of pyridine with benzyl bromide and with a range of benzyl bromides with different para isomer para alkyl substituents reaction product a pyridinium salt . Image Baker Nathan effect.svg The Baker Nathan effect The reaction is facilitated by electron releasing substituents the inductive effect and in general the observed order with decreasing reactivity is tert butyl isopropyl ethyl group ethyl methyl . The observed order in this particular reaction however was methyl ethyl isopropyl tert butyl. In 1 ... more details
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