RTI 352 is a phenyltropane that is used as a radiolabeling ligand for the Dopamine active transporter DAT . US Patent 6358492 RTI 352 has been configured to have 1 R ,2 S ,3 R stereochemistry and is therefore a geometric isomer of CIT . Based on X ray crystallography, this compound is in a tautomer ic equilibrium residing mostly on the side of the boat shaped conformer. Die synthesis runs as follows File Boat tropane synth.png 800px Phenyltropanes Category Tropanes Category RTI compounds ... more details
In chemistry , an imidic acid is any molecule that contains the C NH OH functional group . ref GoldBookRef file I02949 title Imidic acids accessdate 2012 04 02 ref It is the tautomer of an amide . The term imino acid is an obsolete term for this group that should not be used in this context because an imino acid actually has a different technical meaning. ref GoldBookRef file I02959 title Imino acids accessdate 2012 04 02 ref References references Organic chem stub Category Amides ... more details
Oxadiazole is a heterocyclic aromatic chemical compound with the molecular formula C sub 2 sub H sub 2 sub N sub 2 sub O. There are four isomer s of oxadiazole gallery File 1,2,3 oxadiazole.svg 1,2,3 oxadiazole File 1,2,4 oxadiazole.svg 1,2,4 oxadiazole File 1,2,5 oxadiazole.svg furazan 1,2,5 oxadiazole br furazan File 1,3,4 oxadiazole.svg 1,3,4 oxadiazole gallery 1,2,4 Oxadiazole, 1,2,5 oxadiazole, and 1,3,4 oxadiazole are known, but the 1,2,3 isomer is unstable and reverts to the diazo ketone tautomer . ref Heterocyclic Chemistry , 3rd Edition, J. A. Joule, K. Mills, and G.F. Smith, page 452 ref The stable oxadiazoles appear in a variety of pharmaceutical drugs including raltegravir , butalamine , fasiplon , oxolamine , and pleconaril . References reflist Category Oxadiazoles heterocyclic stub hu Oxadiazol ... more details
Chembox Watchedfields changed verifiedrevid 410134784 ImageFile 2 aminopyridine.svg ImageSize 120px IUPACName Pyridin 2 amine OtherNames 2 Pyridinamine 2 Pyridylamine Aminopyridine Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 10008 InChI 1 C5H6N2 c6 5 3 1 2 4 7 5 h1 4H, H2,6,7 InChIKey ICSNLGPSRYBMBD UHFFFAOYAM SMILES1 c1ccnc c1 N ChEMBL Ref ebicite correct EBI ChEMBL 21619 StdInChI Ref stdinchicite correct chemspider StdInChI 1S C5H6N2 c6 5 3 1 2 4 7 5 h1 4H, H2,6,7 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey ICSNLGPSRYBMBD UHFFFAOYSA N CASNo Ref cascite correct CAS CASNo 504 29 0 PubChem 10439 SMILES n1ccccc1N Section2 Chembox Properties C 5 H 6 N 2 Appearance colourless solid Density MeltingPt 59 60 C BoilingPt 210 C Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition 2 Aminopyridine is an organic compound with the formula H sub 2 sub NC sub 5 sub H sub 4 sub N. It is one of three isomer ic aminopyridines. It is a colourless solid that is used in the production of the drugs piroxicam , sulfapyridine , tenoxicam , and tripelennamine . It is produced by the reaction of sodium amide with pyridine , the Chichibabin reaction . ref Shinkichi Shimizu, Nanao Watanabe, Toshiaki Kataoka, Takayuki Shoji, Nobuyuki Abe, Sinji Morishita, Hisao Ichimura Pyridine and Pyridine Derivatives in Ullmann s Encyclopedia of Industrial Chemistry 2000, Wiley VCH, Weinheim. DOI 10.1002 14356007.a22 399 ref Structure Although 2 hydroxypyridine exists in significant amounts as the pyridone tautomer , the related imine tautomer HNC sub 5 sub H sub 4 sub NH is less important for 2 aminopyridine. References references External links http www.alkalimetals.com msds 2 AMINOPYRIDINE MSDS.pdf MSDS DEFAULTSORT Aminopyridine, 2 heterocyclic stub Category Pyridines fa ... more details
Chembox verifiedrevid 447943157 ImageFile Kopexil tautomerism.svg ImageSize 250px ImageAlt IUPACName 2,3 Dihydro 3 hydroxy 2 imino 4 pyrimidinamine br 2,4 Diaminopyrimidine 3 N oxide OtherNames Aminexil Section1 Chembox Identifiers CASNo 113275 13 1 CASNo Ref cascite correct CAS CASNo1 74638 76 9 CASNo1 Ref cascite correct CAS CASNo1 Comment pyridine oxide tautomer PubChem SMILES Section2 Chembox Properties C 4 H 6 N 4 O 1 Appearance white odorless crystals ref name kumar http www.kumarorganic.net files Kopexil MSDS.pdf MSDS for Kopexil at Kumar Organics . March 28th 2012. ref Density MeltingPt 210 218 C ref name kumar BoilingPt Solubility slightly soluble ref name kumar Section3 Chembox Hazards MainHazards FlashPt Autoignition Kopexil is a chemical compound similar to minoxidil . Minoxidil was originally used to treat high blood pressure a side effect was increased body hair. Chemical structure Kopexil is an N oxide , a group of substances in which the nitrogen atom of a tertiary amine is oxidized. The compound can exist in two tautomer ic forms. Mechanism of action The exact mechanism of action of kopexil is unknown. Until now there is no proof of therapeutic effect for kopexil against Androgenic alopecia alopecia . ref Wolfgang Raab Google books NoH2I oiZLQC Haarerkrankungen in Der Dermatologischen Praxis page 82 German . ref References Reflist 2 Category Amine oxides Category Enamines Category Guanidines Category Pyrimidines Category Hair dermatologic drug stub de Kopexil pl Kopexil ... more details
chembox verifiedrevid 378318512 Name Citrazinic acid ImageFile Citrazinic.png ImageSize 160px ImageName IUPACName OtherNames 2,6 Dihydroxyisonicotinic acid 2,6 Dihydroxypyridine 4 carboxylic acid Section1 Chembox Identifiers SMILES CASNo 99 11 6 RTECS Section2 Chembox Properties Formula C sub 6 sub H sub 5 sub NO sub 4 sub MolarMass 155.11 g mol Appearance yellow powder Density Solubility Slightly, with hydrolysis MeltingPt 300 C decomp. BoilingPt Section7 Chembox Hazards ExternalMSDS MainHazards NFPA H NFPA R NFPA F FlashPt RPhrases SPhrases Section8 Chembox Related Function OtherFunctn Citrazinic acid is a heterocyclic compound consisting of a dihydro pyridine ring derived from citric acid . The yellow solid exists as multiple tautomer s as seen also for the simpler 2 pyridone . Citrazinic acid is very sparingly soluble in water, acid and methanol but is soluble in basic solutions eg. ammonia water . For NMR purposes it is also sparingly soluble in d6 dimethyl sulfoxide DMSO 2H, 6.20 ppm . Category Carboxylic acids Category 2 Pyridones fa ... more details
The Fujimoto Belleau reaction is a chemical reaction that forms cyclic substituted , unsaturated ketone s from enol lactone s. The reaction is named after the two chemists George I. Fujimoto and Bernard Belleau . Image Fujimoto Belleau Reaction Scheme.png center 500px The Fujimoto Belleau reaction The reaction is a Grignard reaction, followed by a H shift, an tautomer enol keto tautomerisation and an Aldol addition reaction. The last step is an elimination Aldol condensation reaction with an E sub 1 sub CB mechanism. Image Fujimoto belleau mechanism.jpg center mechanism of the reaction References cite journal title Labeling of Steroids in the 4 Position author George I. Fujimoto journal J. Am. Chem. Soc. volume 73 issue 4 pages 1856 1856 year 1951 url doi 10.1021 ja01148a518 cite journal title The Reaction of Methylmagnesium Iodide with 1 Hydroxy 3,4 dihydro 2 naphthyl butyric Acid Lactone author Bernard Belleau journal J. Am. Chem. Soc. volume 73 issue 11 pages 5441 5443 year 1951 url doi 10.1021 ja01155a504 Weill Raynal, J. Synthesis 1969 , 49. Category Addition reactions Category Carbon carbon bond forming reactions Category Condensation reactions reaction stub Category Name reactions ar es Reacci n de Fujimoto Belleau nl Fujimoto Belleau reactie zh Fujimoto Belleau ... more details
Chembox IUPACName Azinate Section1 Chembox Identifiers SMILES O NH O O StdInChI 1S HNO3 c2 1 3 4 h1H q 2 StdInChIKey MXGJTGDTPQKTCZ UHFFFAOYSA N Section2 Chembox Properties Formula HNO sub 3 sub sup 2 sup MolarMass 63.0128 g mol sup 1 sup ExactMass 62.995642903 g mol sup 1 sup Section3 Chembox Structure Coordination Tetragonal at N MolShape Tetrahedral at N Section4 Chembox Related OtherAnions Nitrate A nitronate IUPAC azinate in organic chemistry is a functional group with the general structure R sub 1 sub R sub 2 sub C N sup sup O sub 2 sub sup 2 sup . ref F. A. Carey, R. J. Sundberg, Organische Chemie, Wiley VCH Verlag 2004 ISBN 3 527 29217 9 ref It is the anion of a nitronic acid, a tautomer ic form of a nitro compound nitro compound. A nitronic acid is also called a aci form . In the Nef reaction nitronic acids are degraded to ketones . They can be alkylated on oxygen and used as a dipole in 1,3 dipolar cycloaddition s. Image Nitronate .png thumb right The structure of a nitronate ion References references Category Functional groups Category Organonitrogen compounds es Nitronato fa nl Nitronaat ru ... more details
The Favorskii reaction not to be confused with the Favorskii rearrangement , named for the Russian chemist Alexei Yevgrafovich Favorskii a.k.a. Alexei Evgrafovich Favorskii , is a special case of nucleophilic attack on a carbonyl group involving a terminal alkyne with carbon acid acidic protons . ref M. Smith, J. March, March s advanced organic chemistry , Wiley Interscience, 2001 ref Image Faworski Reaktion.png center Favorskii reaction scheme plus subsequent rearrangement When catalyzed by acid, this reaction is called the Meyer Schuster rearrangement . Reaction mechanism A metal acetylide is formed in situ when an alkyne is treated with a strong base chemistry bases such as a hydroxide or an alkoxide . The metal acetylide then reacts with an aldehyde or ketone to form a propargyl alcohol . When an alpha hydrogen is present as is the case when the carbonyl is an aldehyde , it will tautomer ize to the corresponding enone . This reaction is used as a protective group protect alkyne s the alkyne is either converted with acetone to a 2 hydroxyprop 2 yl alkyne or converted directly with the commercially available 3 methyl 1 butyne 3 ol also to a protected alkyne. The protective group can be removed by heating the compound in a solution of potassium hydroxide in isopropanol a retro Favorskii reaction . ref T. Greene, P. Wuts, Protective groups in organic synthesis , Wiley Interscience, 1998 ref References Reflist DEFAULTSORT Favorskii Reaction Category Rearrangement reactions Category Name reactions de Faworski Reaktion nl Favorski reactie zh ... more details
Chembox verifiedrevid 446035918 ImageFileL1 Divicine.svg ImageSizeL1 110px ImageCaptionL1 pyrimidine tautomer ImageFileR1 Divicine2.svg ImageSizeR1 95px ImageCaptionR1 pyrimidinone tautomer IUPACName 2,6 diamino 4,5 dihydroxypyrimidine OtherNames 2,6 diamino 4,5 pyrimidinediol 2,6 diamine 5 hydroxy 4 3 H pyrimidinone 2,4 diamino 5,6 dihydroxypyrimidine Section1 Chembox Identifiers CASNo 32267 39 3 CASNo Comment ref name ChemboxRef http www.druglead.com cds divicine.html ref PubChem 91606 SMILES OC1 C O C N NC N N1 SMILES Comment pyrimidine tautomer SMILES1 O C1C O C N NC N N1 SMILES1 Comment pyrimidinone tautomer ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 2971290 InChI 1 C4H6N4O2 c5 2 1 9 3 10 8 4 6 7 2 h9H, H5,5,6,7,8,10 InChIKey ZMWZGZSARWJATP UHFFFAOYAO StdInChI Ref stdinchicite correct chemspider StdInChI 1S C4H6N4O2 c5 2 1 9 3 10 8 4 6 7 2 h9H, H5,5,6,7,8,10 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey ZMWZGZSARWJATP UHFFFAOYSA N Section2 Chembox Properties C 4 H 6 N 4 O 2 Appearance Brownish needles Density MeltingPt BoilingPt Solubility Soluble in 10 KOH Section3 Chembox Hazards MainHazards FlashPt Autoignition Divicine 2,6 diamino 4,5 dihydroxypyrimidine is an oxidant and a base with alkaloidal properties found in fava beans and Lathyrus sativus . It is an aglycone of vicine . A common derivative is the diacetate form 2,6 diamino 1,6 dihydro 4,5 pyrimidinedione . ref name Structure cite journal author Bendich, C. year 1953 journal Biochim. Biophys. volume 12 page 462 ref Occurrence Divicine is found in fava beans and in the legume Lathyrus sativus , also known as khesari, which is a cheap and robust food source commonly grown in Asia and East Africa. Synthesis In plants, reduced divicine is formed from the hydrolysis of the inactive glucoside, vicine . ref name Baker cite journal author Baker, M. Bosia, A. year 1984 title Mechanism of Action of Divicine in a Cell free System and in Glucose 6 phosphate Dehydrogenase defic ... more details
to the enol tautomer of guanine, selectively base pairs with thymine instead of cytosine . This results ..., in a manner analogous to the imine tautomer of adenine, selectively base pairs with cytosine instead ... more details
Image Bisulfite S H tautomer 3D balls.png thumb right 200px A ball and stick model of the most commonly stated structure for the bisulfite ion in solution and in the solid state. Bisulfite ion IUPAC recommended nomenclature hydrogen sulfite is the ion HSO sub 3 sub sup sup . Salts containing the HSO sub 3 sub sup sup ion are termed bisulfites also known as sulfite lyes. For example, sodium bisulfite is NaHSO sub 3 sub . Reactions Bisulfite salts are typically prepared by treatment of alkaline solutions with excess sulfur dioxide SO sub 2 sub NaOH NaHSO sub 3 sub HSO sub 3 sub sup sup is the conjugate base of sulfurous acid , H sub 2 sub SO sub 3 sub H sub 2 sub SO sub 3 sub unicode HSO sub 3 sub sup sup H sup sup Sulfurous acid is not an isolable compound and does not appear to exist in solution either. An equilibrium that is much more consistent with spectroscopy spectroscopic evidence is given SO sub 2 sub H sub 2 sub O unicode HSO sub 3 sub sup sup H sup sup HSO sub 3 sub sup sup is a weakly acidic species with a acid dissociation constant p K sub a sub of 6.97. Its conjugate base is the sulfite ion, SO sub 3 sub sup 2 sup HSO sub 3 sub sup sup unicode SO sub 3 sub sup 2 sup H sup sup Bisulfites are reducing agents, as are all sulfites and sulfur dioxide, which contains sulfur in the same oxidation state 4 . Structure Image Bisulfite equilibrium 2D.png 300px thumb right Bisulfite tautomers in equilbrium Image Bisulfite equilibrium 3D balls.png 300px thumb right Ball and stick models of the proposed bisulfite equilbrium. The tautomer on the left has C sub s sub symmetry, while that of the tautomer on the right is C sub 3v sub . Some evidence may suggest that the proton in bisulfite ion is located on sulfur, giving rise to molecular symmetry C sub 3v sub symmetry . There is, however, some evidence from oxygen 17 sup 17 sup O nuclear magnetic resonance spectroscopy NMR spectroscopy to suggest that two tautomeric forms of HSO sub 3 sub sup sup exist in dynamic equilibrium ... more details
Drugbox verifiedrevid 443405335 IUPAC name 4 amino N 1,3 thiazol 2 yl benzenesulfonamide image Sulfathiazole skeletal.svg Clinical data tradename Drugs.com drugs.com international sulfathiazole pregnancy category legal status routes of administration Pharmacokinetic data bioavailability metabolism excretion Identifiers CASNo Ref cascite correct CAS CAS number 72 14 0 ATC prefix D06 ATC suffix BA02 ATC supplemental ATC J01 EB07 ATCvet J01 EQ07 PubChem 5340 DrugBank Ref drugbankcite correct drugbank DrugBank DB06147 ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 5148 UNII Ref fdacite correct FDA UNII Y7FKS2XWQH KEGG Ref keggcite correct kegg KEGG D01047 ChEBI Ref ebicite correct EBI ChEBI 9337 ChEMBL Ref ebicite correct EBI ChEMBL 437 Chemical data C 9 H 9 N 3 O 2 S 2 molecular weight 255.319 g mol smiles O S O Nc1nccs1 c2ccc N cc2 InChI 1 C9H9N3O2S2 c10 7 1 3 8 4 2 7 16 13,14 12 9 11 5 6 15 9 h1 6H,10H2, H,11,12 InChIKey JNMRHUJNCSQMMB UHFFFAOYAE StdInChI Ref stdinchicite correct chemspider StdInChI 1S C9H9N3O2S2 c10 7 1 3 8 4 2 7 16 13,14 12 9 11 5 6 15 9 h1 6H,10H2, H,11,12 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey JNMRHUJNCSQMMB UHFFFAOYSA N Sulfathiazole is an organosulfur compound that has been used as a short acting Sulfonamide medicine sulfa drug . It once was a common oral and topical antimicrobial until less toxic alternatives were discovered. It is still occasionally used, sometimes in combination with sulfabenzamide and sulfacetamide , and in aquarium s. It exists in various forms Polymorphism materials science polymorph s . The imide tautomer is dominant, at least in the solid state. In this tautomer, the proton residing on the ring nitrogen not the structure shown above . ref G. J. Kruger and G. Gafner The crystal structure of sulphathiazole II Acta Cryst. 1971 . B27, 326 333. doi 10.1107 S0567740871002176 ref Cultural references Sulfathiazole is mentioned in chapter 104 of Kurt Vonnegut s novel Cat s Cradle and New Dic ... more details
Chembox ImageFileL1 Nitrosourea.png ImageFileL1 Ref chemboximage correct ?? ImageSizeL1 121 ImageNameL1 Skeletal formula of a minor tautomer of nitrosourea ImageFileR1 Nitrosourea 3D balls.png ImageFileR1 Ref chemboximage correct ?? ImageSizeR1 121 ImageNameR1 Ball and stick model a minor tautomer of nitrosourea IUPACName Nitrosourea Section1 Chembox Identifiers CASNo 13010 20 3 CASNo Ref cascite changed ?? PubChem 105035 PubChem Ref Pubchemcite correct PubChem ChemSpiderID 94772 ChemSpiderID Ref chemspidercite correct chemspider SMILES NC O N NO SMILES1 C O N NN O StdInChI 1S CH3N3O2 c2 1 5 3 4 6 h H3,2,3,5,6 StdInChI Ref stdinchicite correct chemspider StdInChIKey OSTGTTZJOCZWJG UHFFFAOYSA N StdInChIKey Ref stdinchicite correct chemspider Section2 Chembox Properties C 1 H 3 N 3 O 2 ExactMass 89.022526355 g mol sup 1 sup Image Urea.png thumb 240px Urea Image Streptozotocin Structure NTP.png thumb 240px Streptozotocin Image Ethylnitrosourea.svg thumb 240px ENU Nitrosourea is both the name of a molecule, and a class of compounds that include a nitroso R NO group and a urea . Examples Examples include Carmustine Lomustine Semustine Ethylnitrosourea ENU Streptozotocin Nitrosourea compounds are DNA alkylating antineoplastic agent alkylating agents and are often used in chemotherapy . ref name urlantineop cite web url http faculty.swosu.edu scott.long phcl antineop.htm title Antineop format work accessdate 2009 01 24 ref They are lipophile lipophilic and thus can cross the blood brain barrier , making them useful in the treatment of brain tumor s such as glioblastoma multiforme . ref Takimoto CH, Calvo E. http www.cancernetwork.com cancer management 11 chapter03 article 10165 1402628 Principles of oncologic pharmacotherapy . in Pazdur R, Wagman LD, Camphausen KA, Hoskins WJ Eds http www.cancernetwork.com cancer management 11 Cancer management a multidisciplinary approach . 11 ed. 2008. ref Side effects Some nitrosoureas e.g. lomustine have been associated with the develo ... more details
The Bucherer reaction in organic chemistry is the reversible conversion of naphthol to naphthylamine in presence of ammonia and sodium bisulfite . ref cite journal author H. Bucherer title ber die Einwirkung schwefligsaurer Salze auf aromatische Amido und Hydroxylverbindungen journal Journal f r Praktische Chemie year 1904 pages 49 91 volume 69 doi 10.1002 prac.19040690105 issue 1 ref ref H Seeboth. Angew Chem Int Ed 6 4 1967 307 317 mechanisme http dx.doi.org 10.1002 anie.196703071 DOI ref ref Drake, N. L. Organic Reactions Org. React. 1942 , 1 . ref ref W P tsch. Lexikon bedeutender Chemiker VEB Bibliographisches Institut Leipzig, 1989 ISBN 978 3323001855 ref ref M B Smith, J March. March s Advanced Organic Chemistry Wiley, 2001 ISBN 0 471 58589 0 ref Image Buchereralg.png 400px Bucherer reaction The French chemist Robert Lepetit was the first to discover the reaction in 1898 but it was the German chemist Hans Theodor Bucherer 1869 1949 who discovered independent from Lepetit its reversibility and its potential in chemistry especially in industry. Bucherer published his results in 1904 and his name is connected to this reaction. The organic reaction also goes by the name Bucherer Lepetit reaction or wrongly the Bucherer Le Petit reaction. Mechanism in the first step of the reaction mechanism a proton adds to a carbon atom with high electron density therefore by preference to C2 or C4 of naphthol 1 . This leads to resonance structure resonance stabilized adducts 1a 1e . De aromatization of the first ring of the naphthalene system occurs at the expense of 25 kcal mol. In the next step a bisulfite anion adds to C3 through 1e . This results in the formation of 3a which tautomer izes to the more stable 3b to the sulfonic acid of tetralone . A nucleophilic addition follows of the amine with formation of 4a and its tautomer 4b loses water to form the resonance stabilized cation 5a . This compound is deprotonated to the imine 5b or the enamine 5c but an equilibrium exist ... more details
to draw a tautomer of 2 cyanoguanidine with the structure NC NH C NH NH2. Further tautomerization ... tautomer followed by deprotonation gives the anion commonly referred to the dicyanamide ion, NC sub ... more details
. The Direct Polymerization of Vinyl Alcohol, the Enolic Tautomer of Acetaldehyde. Anna K. Cederstav ... tautomer. The existence of hydrogen atom at alpha carbon is necessary but not sufficient condition ... form is, in general, more stable than its enol tautomer. As the lower energy form, the keto form is favored ... substituents, the conversion of the enol to the keto tautomer affords enantiomers . On the other ... more details
Image Diacetyl structure.png thumb right 100px Diacetyl , the simplest diketone A diketone is a molecule containing two ketone Functional group groups . The simpliest diketone is diacetyl , also known as 2,3 butanedione. Diacetyl, acetylacetone , and hexane 2,5 dione are examples of 1,2 , 1,3 , and 1,4 diketones, respectively. Dimedone is an example of a cyclic diketone. Reactions 1,3 Diketones, such as acetylacetone, are particularly prone to form stable enol enols or enolate enolates because of Conjugated system conjugation of the enol or enolate with the other carbonyl group, and the stability gained in forming a six membered ring, hydrogen bonded in the case of the enol or containing the counter ion in the case of the enolate . Image acacH.png 400px Scheme 1. Tautomerism of 2,4 pentanedione The conjugate base derived from 1,3 ketones form complexes with metal ions. Diketones with one or two methylene groups separating the carbonyl groups typically coexist with their enolization enol tautomer s. The reactions of such dicarbonyls are very similar to those of simple ketones. In the DeMayo reaction 1,3 diketones react with alkenes in a photochemical pericyclic reaction to form substituted 1,5 diketones. EU Regulation In 2004, the EU conducted an examination of certain flavoring Food additive additives grouped together as Flavouring Group Evaluation FGE.11 . This group included diketones. ref http www.efsa.europa.eu EFSA Scientific Opinion afc opinionflav ej166 en1.pdf Opinion of the Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in contact with Food , EFSA Journal 2004 166, 1 44 ref As part of that study, the EU found that acetylacetone pentane 2,4 dione FL 07.191 was genotoxic in vivo and in vitro , and deleted it from the register of permitted flavoring substances. ref http eur lex.europa.eu LexUriServ site en oj 2005 l 128 l 12820050521en00730076.pdf COMMISSION DECISION of 18 May 2005 amending Decision 1999 217 EC as regards the re ... more details
about a class of chemical compounds the chemical company Enamine Ltd Image Enamine 2D skeletal.png thumb right 200px The general structure of an enamine An enamine is an saturation chemistry unsaturated compound derived by the reaction of an aldehyde or ketone with a secondary amine followed by loss of H sub 2 sub O. ref cite book author Clayden, Jonathan authorlink editor others title Organic chemistry edition language publisher Oxford University Press location Oxford, Oxfordshire year 2001 origyear pages pages chapter chapter isbn 0 19 850346 6 oclc doi url http www.organic chemistry.org books reviews 0198503466.shtm accessdate ref ref Housecroft3rd ref The word enamine is derived from the affix en , used as the suffix of alkene , and the root amine . This can be compared with enol , which is a functional group containing both alkene en and alcohol ol . Enamines are considered to be nitrogen analogs of enols. ref http pharmaxchange.info press 2011 04 imines and enamines nitrogen analogs of enols and enolates Imines and Enamines PharmaXChange.info ref If one of the nitrogen substituents is a hydrogen atom, H, it is the tautomer ic form of an imine . This usually will rearrange to the imine however there are several exceptions such as aniline . The enamine imine tautomerism may be considered analogous to the keto enol tautomerism . In both cases, a hydrogen atom switches its location between the heteroatom oxygen or nitrogen and the second carbon atom. Enamines are both good nucleophiles and good bases. References reflist 2 See also Thorpe reaction Category Functional groups Category Enamines de Enamine es Enamina fr namine gl Enamina id Enamina it Enammina hu Enaminok nl Enamine ja pl Enaminy pt Enamina ru sr Enamin fi Enamiinit sv Enamin zh ... more details
Azirines are three membered heterocyclic unsaturated i.e. they contain a double bond compounds containing a nitrogen atom and related to the saturated analogue aziridine . ref cite journal author Teresa M. V. D. Pinho e Melo and Antonio M. d A. Rocha Gonsalves journal Current Organic Synthesis volume 1 issue 3 year 2004 pages 275 292 title Exploiting 2 Halo 2H Azirine Chemistry url http www.bentham.org cos contabs cos1 3.htm 5 doi 10.2174 1570179043366729 ref They are highly reactive yet are found in a number of Biomolecule natural products such as the antibiotic azirinomycin , isolated from Streptomyces auras . There are two isomer s of azirine 1 H azirines with a carbon carbon double bond are not stable and rearrange to the tautomer ic 2 H azirine, a compound with a carbon nitrogen double bond. 2 H Azirines can be considered strained imine s and are isolable. Preparation 2 H Azirines are most often obtained by the thermolysis of vinyl azide s. ref cite journal title 2 H Azirines as synthetic tools in organic chemistry author F. Palacios, A. M. Ochoa de Retana, E. Martinez de Marigorta, J. M. de los Santos journal Eur. J. Org. Chem year 2001 pages 2401 2414 doi 10.1002 1099 0690 200107 2001 13 2401 AID EJOC2401 3.0.CO 2 U volume 2001 issue 13 ref During this reaction, a nitrene is formed as an intermediate. Alternatively, they can be obtained by oxidation of the corresponding aziridine . Image Synth Azirin.png 350px Azirine synthesis br style clear left Reactions Photolysis of azirines under 300 nm is a very efficient way to generate nitrile ylide s. These nitrile ylides are 1,3 dipole dipolar compounds and can be trapped by a variety of dipolarophiles to yield heterocyclic compounds, e.g. pyrroline s. The strained ring system also undergoes reactions that favor ring opening and can act as a nucleophile or an electrophile . An azirine is an intermediate in the Neber rearrangement . References reflist Category Nitrogen heterocycles Category Imines be de Aziri ... more details
The Elbs persulfate oxidation is the organic reaction of phenol s with alkaline potassium persulfate to form Aromatic para position para diphenols. ref Elbs, K. J. Prakt. Chem. 1893 , 48 , 179. ref Image Elbs Persulfate Oxidation Scheme.png center 400px The Elbs persulfate oxidation Several reviews have been published. ref cite journal author S. M. Sethna title The Elbs Persulfate Oxidation year 1951 journal Chem. Rev. volume 49 issue 1 pages 91 101 doi 10.1021 cr60152a002 ref ref Lee, J. B. Uff, B. C. Quart. Rev. 1967 , 21 , 453. Review ref ref Behrman, E. J. Org. React. 1988 , 35 , 421 511. Review ref Reaction mechanism A reaction mechanism has been postulated accounting for the observed para substitution featuring the tautomer ic para carbanion of the starting phenolate ion ref cite journal author E. J. Behrman title The Elbs and Boyland Sims peroxydisulfate oxidations year 2006 journal Beilstein Journal of Organic Chemistry volume 2 issue 1 pages 22 doi 10.1186 1860 5397 2 22 pmid 17090305 pmc 1697820 ref Image ElbsReactionMechanism.png center 500px The Elbs persulfate oxidation reaction mechanism which gives a nucleophilic displacement on the peroxide oxygen of the peroxodisulfate peroxydisulfate ion. The intermediate sulfate group is then hydrolyzed to the hydroxyl group . The reaction is disadvantaged by low chemical yield s with recovery of starting material and complete consumption of the persulfate . It is suggested that the phenol in many cases is a catalyst converting the persulfate into a sulfate. References references 6. E. J. Behrman, Chemical Educator, 15, 392 393 2010 See also Boyland Sims oxidation DEFAULTSORT Elbs Persulfate Oxidation Category Organic redox reactions Category Name reactions de Elbs Oxidation es Oxidaci n del persulfato de Elbs ja zh Elbs ... more details
DISPLAYTITLE C sub 3 sub H sub 6 sub O The molecular formula C sub 3 sub H sub 6 sub O may refer to Image C3H6Oisomer.jpg thumb right 350px portal Chemistry Alcohol s Allyl alcohol or 2 propenol 1, CH sub 2 sub CH CH sub 2 sub OH, CAS number CAS 107 18 6 cyclopropanol or cyclopropyl alcohol, cyclo CH sub 2 sub CH sub 2 sub HOHC , CAS number CAS 16545 68 9 Aldehyde s propanal or propionaldehyde , CH sub 3 sub CH sub 2 sub CHO, CAS number CAS 123 38 6 Ketone s 2 propanone or acetone , CH sub 3 sub CO CH sub 3 sub , CAS number CAS 67 64 1 Enol s tautomer s of aldehydes and ketones E 1 propenol , CH sub 3 sub CH CH OH, CAS number CAS 57642 95 2 Z 1 propenol , CH sub 3 sub CH CH OH, CAS number CAS 57642 96 3 2 propenol , CH sub 2 sub C OH CH sub 3 sub , CAS number CAS 29456 04 0 or CAS 74324 85 9 Ether s methyl vinyl ether or methoxyethene, H sub 3 sub C O CH CH sub 2 sub , CAS number CAS 107 25 5 oxetane or trimethylene oxide, cyclo CH sub 2 sub CH sub 2 sub O CH sub 2 sub , CAS number CAS 503 30 0 1,2 epoxy propane or Propylene oxide or methyl oxirane, cyclo C H CH sub 3 sub CH sub 2 sub O , C Chirality chemistry chiral , CAS number CAS 75 56 9 R methyl oxirane, CAS number CAS 15448 47 2 S methyl oxirane, CAS number CAS 16088 62 3 MolFormDisambig el C3H6O fr C3H6O it C3H6O lv C3h6o sr C3H6O ... more details
chembox verifiedrevid 443885075 ImageFile Isoindol.svg ImageSize 150px ImageName Skeletal formula ImageFile1 Isoindole 3D balls.png ImageName1 Ball and stick model IUPACName 2 H Isoindole OtherNames Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 2282425 InChI 1 C8H7N c1 2 4 8 6 9 5 7 8 3 1 h1 6,9H InChIKey VHMICKWLTGFITH UHFFFAOYAW StdInChI Ref stdinchicite correct chemspider StdInChI 1S C8H7N c1 2 4 8 6 9 5 7 8 3 1 h1 6,9H StdInChIKey Ref stdinchicite correct chemspider StdInChIKey VHMICKWLTGFITH UHFFFAOYSA N CASNo 270 68 8 PubChem 3013853 ChEBI Ref ebicite correct EBI ChEBI 33179 SMILES c1cccc2c1cnc2 Section2 Chembox Properties Formula C sub 8 sub H sub 7 sub N MolarMass 117.15 g mol Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Isoindole in heterocyclic chemistry is a arene compound benzo fused pyrrole . ref Heterocyclic chemistry T.L. Gilchrist ISBN 0 582 01422 0 ref The compound is an isomer of indole and its organic reduction reduced form is an isoindoline . In solution its tautomer without full aromaticity over the whole ring system is predominant Citation needed date February 2008 File Isoindoletautomerism.png 400px Isoindole tautomerism and therefore the compound resembles a pyrrole more than a simple imine . Isoindoles are building blocks for phthalocyanine s which are relevant as dyes Isoindole 1,3 diones The commercially important phthalimide is an isoindole 1,3 dione with two carbonyl groups attached to the heterocyclic ring. Thalidomide is an infamous drug based on this framework. See also Isoindene with nitrogen replaced by a methylene group. References reflist Category Isoindoles ar fr Isoindole nl Iso indool ja ... more details
Ethylene Vinyl Alcohol , commonly abbreviated EVOH , is a formal copolymer of ethylene and vinyl alcohol . Because the latter monomer mainly exists as its tautomer acetaldehyde , the copolymer is prepared by polymerization of ethylene and vinyl acetate to give the ethylene vinyl acetate EVA copolymer followed by hydrolysis. The plastic resin is commonly used in food applications, and it has lately found application in plastic gasoline tanks for automobiles. Its primary purpose is to provide barrier properties, primarily as an oxygen barrier for improved food packaging shelf life and as a hydrocarbon barrier for fuel tanks. EVOH is typically coextruded or laminated as a thin layer between cardboard, foil, or other plastics. EVOH copolymer is defined by the mole ethylene content lower ethylene content grades have higher barrier properties higher ethylene content grades have lower temperatures for extrusion . Industrial Production The company EVAL Europe started up in 2004 in Zwijndrecht, Belgium Zwijndrecht Belgium the biggest production facility of the world with a capacity of 24.000 ton a. ref http www.foodproductiondaily.com Packaging EVAL completes world s largest EVOH resin plant EVAL completes world s largest EVOH resin plant . Foodproductiondaily.com, 3. November 2004. ref Nippon Gohsei has three 3 production sites in Japan, US and Europe. In 2004, Nippon Gohsei started production at its Hull, UK, site having the world s largest single line capacity. ref http www.csr4u.co.uk NGUK 20Case 20Study.htm Nippon Gohsei The right strategy to get the results www.csr4u.co.uk. ref It is sold under the trade name SoarnoL. Use in medical applications EVOH is used in liquid embolic system in inverventional radiology, e.g. in Onyx Interventional radiology Onyx . ref http www.ajnr.org cgi reprint 30 1 99 Embolization of Intracranial Arteriovenous Malformations with Ethylene Vinyl Alcohol Copolymer Onyx . American Journal of Neuroradiology 30 99 106, January 2009. ref Dissolved ... more details
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