atom. Basicaromatic compounds get Protonation protonated and form aromatic cation s e.g. pyridinium under acid ic conditions. Typical examples of basicaromatic rings are pyridine or quinoline . Several rings contain basic as well as non basic nitrogen atoms, e.g. imidazole and purine . In non basicaromatic rings the lone pair of electron s of the nitrogen atom is delocalized and contributes to the aromatic .... Examples of non basic nitrogen containing aromatic rings are pyrrole and indole . The basicaromatic rings purine s and pyrimidine s are nucleobases found in DNA and RNA . See also Simple aromaticring DEFAULTSORT BasicAromaticRing Category Nitrogen heterocycles ar ur ... more details
. Heterocyclic aromatic rings The nitrogen N containing aromatic rings can be separated into basicaromaticring s that are easily protonation protonated , and form aromatic cation s and salts e.g., pyridinium , and non basicaromatic rings. In the basicaromatic rings , the lone pair of electron s is not part of the aromatic system and extends in the plane of the ring. This lone pair is responsible ... the nitrogen atom is not connected to a hydrogen atom. Examples of basicaromatic rings are pyridine or quinoline . Several rings contain basic as well as non basic nitrogen atoms, e.g., imidazole and purine . In the non basic rings , the lone pair of electrons of the nitrogen atom is delocalized ... to a hydrogen atom. Examples of non basic nitrogen containing aromatic rings are pyrrole ... contributes to the aromatic system similar to the non basic nitrogen containing rings , whereas the second lone pair extends in the plane of the ring similar to the basic nitrogen containing ... hydrocarbons PAH References reflist 2 DEFAULTSORT Simple AromaticRing Category Simple aromatic rings ...Simple aromatic rings , also known as simple arenes or simple aromatics , are aromatic organic compound s that consist only of a conjugated system conjugated planar ring system with delocalized electron delocalized pi electron clouds. Many simple aromatic rings have trivial names. They are usually found ... simple aromatic compounds are benzene , indole , and cyclotetradecaheptaene . ref name Clayden1st ... pages isbn 3527307206 ref Simple aromatic rings can be heterocyclic if they contain non carbon ring atoms, for example, oxygen , nitrogen , or sulfur . They can be monocyclic as in benzene, bicyclic as in naphthalene , or polycyclic as in anthracene . Simple monocyclic aromatic rings are usually five membered rings like pyrrole or six membered rings like pyridine . Fused aromatic rings consist ... 5 cellspacing 0 style margin 1em colspan 3 align center Table of simple aromatic rings WARNING ... more details
about aromatic chemistry the meteorological effect Ring current Image Aromaticring current.png thumb right 250px A diagram of an aromaticring current. B sub 0 sub is the applied magnetic field, the red arrow indicating its direction. The orange ring shows the direction of the ring current, and the purple rings show the direction of the electromagnetic induction induced magnetic field. An aromaticring current is an effect observed in aromaticity aromatic molecules such as benzene and naphthalene . If a magnetic field is directed perpendicular to the plane of the aromatic system, a ring current is induced in the delocalized pi bond electrons of the aromaticring. ref The induced magnetic field ... non aromatic molecules, they respond much more strongly to the magnetic field. Aromaticring currents ... proton in cyclohexene . In contrast any proton inside the aromaticring experiences shielding ... 13 sup 13 sup C and hydrogen atom sup 1 sup H atomic nucleus nuclei in aromatic molecules, ref Aromaticity and Ring Currents. Gomes, J. A. N. F. Mallion, R. B. Chem. Rev. Review 2001 101 5 1349 1384. DOI 10.1021 cr990323h ref as well as in any organic or inorganic aromatic molecule. The effect helps .... In benzene, the ring protons experience deshielding because the induced magnetic field has ... 1.1 ppm. Hence a diamagnetic ring current or diatropic ring current is associated with aromaticity whereas a paratropic ring current signals antiaromaticity. A similar effect is observed in three .... 44, No. 12, pp. 1843 1846, 2005 DOI 10.1002 anie.200462348 PMID 15706578 ref Image Benzene ring currents.png ... the C sub 6 sub ring. Relative aromaticity align right class wikitable colspan 2 align center ... to quantify aromaticity with respect to the observed ring current. ref What is aromaticity? Paul von ... and a calculated value based on group additivity tables. Benzene is clearly aromatic &minus 13.4 , borazine &minus 1.7 and cyclohexane 1.1 are not aromatic and cyclobutadiene 18 is antiaromatic ... more details
Aromaticring hydroxylating dioxygenases ARHD incorporate two atoms of dioxygen O sub 2 sub into their substrates in the dihydroxylation reaction. The product is substituted cis 1,2 dihydroxycyclohexadiene, which is subsequently converted to substituted benzene glycol by a cis diol dehydrogenase. A large family of multicomponent mononuclear non heme iron oxygenases has been identified. Components of bacterial aromaticring dioxygenases constitute two different functional classes hydroxylase components and electron transfer components. Hydroxylase components are either sub n sub or sub n sub oligomers. Two prosthetic groups, a Rieske protein Rieske type Fe sub 2 sub S sub 2 sub center and a mononuclear iron, are associated with the subunit in the sub n sub type enzymes. Electron transfer components are composed of flavoprotein NADH ferredoxin oxidoreductase and Rieske type Fe sub 2 sub S sub 2 sub ferredoxin. In benzoate and toluate 1,2 dioxygenase systems, a single protein containing reductase and Rieske type ferredoxin domains transfers the electrons from NADH to the hydroxylase component. In the phthalate 4,5 dioxygenase system, phthalate dioxygenase reductase PDR has the same function. PDR is a single protein comprising FMN binding reductase and plant type ferredoxin domains. Thus, the electron transfer in ARHD systems can be summarised as ul border 0 width 60 cellpadding 3 cellspacing 1 center NADH center center center bgcolor yellow center reductase br FAD or FMN ... of the bacterial aromaticring hydroxylating dioxygenases journal Adv. Microb. Physiol. year ... from Rhodococcus sp. strain RHA1 InterPro IPR001663 InterPro entry for Bacterial ring hydroxylating dioxygenase, alpha subunit DEFAULTSORT AromaticRing Hydroxylating Dioxygenases Category Metalloproteins ..., E., Parales, R.E., Gibson, D.T., Eklund, H. and Ramaswamy, S. title Structure of an aromaticring hydroxylating dioxygenase &ndash naphthalene 1,2 dioxygenase journal Structure year 1998 volume ... more details
Unreferenced date December 2009 An aromatic amine is an amine with an aromaticity aromatic substituent that is nitrogen N hydrogen H sub 2 sub , nitrogen N hydrogen H or nitrogen group s attached to an aromatic hydrocarbon , whose structure usually contains one or more benzene ring s. Aniline is the simplest example. Aromatic amines, when protonated, usually have lower pKa s are more acidic than their non aromatic analogs. This is due to the delocalization of the lone pair of electrons from the nitrogen into the ring. align center class wikitable colspan 6 align left style background ccccff Representative anilines Aromatic amine CAS number Properties Uses Aniline Image Aniline 2D skeletal.png 50px Aniline 62 53 3 O Toluidine o Toluidine Image O toluidinePIC.svg 100px o toluidine 95 53 4 2,4,6 Trimethylaniline Image TrimethylanilinePIC.svg 100px 88 05 1 O Anisidine Anisidine Image 2 Anisidine.png 75px Anisidine 90 04 0 3 Trifluoromethylaniline Image 3 trifluoromethylanilinePIC.svg 100px 3 trifluoromethylaniline 98 16 8 Intermediate for herbicides, metabolite N Methylaniline N Methylaniline Image N methylaniline.png 60px N methylaniline 100 61 8 See also Aromatic hydrocarbons DEFAULTSORT Aromatic Amine Category Aromatic amines hu Arom s aminok ja pl Aminy aromatyczne pt Amina arom tica sk Aromatick am n zh ... more details
Aromatic sulfonation is an organic reaction in which a hydrogen atom on an aromatic hydrocarbon arene is replaced by a sulfonic acid functional group in an electrophilic aromatic substitution . ref JerryMarch . ref File Benzene sulfonation overview.png center 500px Sulfonation of Benzene to benzene sulfonic acid Mechanism Sulfur trioxide is the electrophile in this electrophilic aromatic substitution generated from concentrated sulfuric acid or fuming sulfuric acid when heated. With benzene as substrate the reaction product is benzenesulfonic acid . Image Chem Mech SO3FormationWH2SO4.png generation of sulfur trioxide from sulfuric acid In contrast to aromatic nitration and other electrophilic aromatic substitutions this reaction is Reversible reaction reversible . Sulfonation takes place in concentrated acidic conditions and desulfonation is the mode of action in a dilute hot aqueous acid. It is very useful in protection group protecting the aromatic system because of this reversibility. Piria reaction A classic named reaction is the Piria reaction R. Piria , 1851 in which nitrobenzene is reacted with a metal bisulfite forming an aminosulfonic acid as a result of combined nitro group reduction and sulfonation. ref Piria, Ann. 78 31 1851 . ref ref THE PIRIA REACTION. I. THE OVER ALL REACTION W. H. Hunter, Murray M. Sprung J. Am. Chem. Soc. , 1931, 53 4 , pp 1432 1443 DOI 10.1021 ja01355a037 . ref File Piria reaction.png 400px center The Piria Reaction Tyrer sulfonation process In the Tyrer sulfonation process 1917 ref US patent 1,210,725 ref , at some time of technological importance, benzene vapor is led through a vessel containing 90 sulfuric acid the temperature of which is increased from 100 to 180 C. Water and benzene are continuously removed in a condenser and the benzene ..., Leipzig, 1985, p. 511, ISBN 3 342 00280 8. ref Application Aromatic sulfonic acids are intermediates ... Electrophilic halogenation Nitration References Reflist DEFAULTSORT Aromatic Sulfonation Category ... more details
Aromatic rice is one of the Oryza sativa Classification major types of rice ref cite web url http www.ers.usda.gov briefing Rice SpecialArticle USricemarket.pdf title The U.S. Rice Export Market publisher United States Department of Agriculture USDA date Nov 2000 br There are four types of rice traded globally indica, japonica rice japonica , aromatic, and glutinous rice glutinous . ref , it is a medium to long grained rice . It is known for its nut fruit nut like aroma and taste , which is caused by the chemical compound 2 acetyl 1 pyrroline . ref cite web url http www.springerlink.com content m53xn058318q4858 title Enhanced resistance to two stem borers in an aromatic rice containing a synthetic cryIA b gene ref Varieties of aromatic rice include basmati , Jasmine rice jasmine , Texmati, Wehani , and wild pecan rice. When cooked, the grains have a light and fluffy texture. References reflist Varieties of rice Category Varieties of rice ja food stub ... more details
wiktionarypar basicBasic may refer to Computing BASIC , a computer programming language Basic access authentication in HTTP Visual Basic , a computer programming language Visual Basic .NET , a computer programming language based on the .NET Framework Other BASIC countries , Brasil, South Africa, India and China in climate change negotiations Basic cigarette , a brand of cigarettes manufactured by the Altria Group Philip Morris Company Basic chemistry , having the properties of a base Basic dance move , the dance move that defines the character of a particular dance Basic film Basic film , a 2003 film by John McTiernan and starring John Travolta and Samuel L. Jackson Basic Instinct , a 1992 erotic thriller by Paul Verhoeven , starring Michael Douglas and Sharon Stone Basic Robert Quine and Fred Maher album Basic Robert Quine and Fred Maher album , 1984 Basic Glen Campbell album Basic Glen Campbell album , 1978 Languages in Star Wars Basic the common intergalactic language Basic , the common intergalactic language in Star Wars British American Security Information Council See also Base disambiguation Bassic Swedish musician and composer Martin Lindhe disambig de Basic Begriffskl rung fr Basic ko it Basic ja simple Basic ... more details
Infobox software name BASIC A logo screenshot caption developer Optimized Systems Software Release date 1983 latest release version latest release date operating system Atari 8 bit family Atari 400 800 XL XE Media floppy disk genre BASIC programming language BASIC license Copyright 1983 Optimized Systems Software Proprietary software Proprietary BASIC A was developed by Optimized Systems Software of Cupertino, California , USA , to provide the Atari 8 bit family with an extended BASIC programming language BASIC compatible with, but faster than, the simpler read only memory ROM based Atari BASIC . While Atari BASIC came on an 8 kilobyte KB ROM cartridge, BASIC A was delivered on floppy disk and took 15 KB of the computer s RAM, leaving 23 KB available for user programs in a 48 KB Atari 800. BASIC A was offered at a price of US 80.00 in 1983, including the products OS A and EASMD Editor Assembler , and being an extension of Atari BASIC, came with a supplement to the latter s reference manual as its documentation. In addition to being faster than its ROM bound counterpart, BASIC A provided a number of extra commands for DOS operations, sprite computer graphics player missile graphics, and debugging . See also Turbo Basic XL External links http www.atarimagazines.com v2n2 productreviews.html BASIC A product review &ndash by Richard E. DeVore, in ANTIC Vol.2, No.2, May 1983 DEFAULTSORT Basic A Category BASIC interpreters Category Optimized Systems Software de BASIC A es BASIC A it BASIC A ... more details
About the programming language other uses Basic disambiguation Infobox programming language paradigm ... logo File AtariBasicExample.png frameless caption Screenshot of Atari BASIC , an early BASIC language ... Eugene Kurtz developer latest release version latest release date typing implementations Apple BASIC , Atari BASIC , Commodore BASIC , Microsoft BASIC , Liberty BASIC , BBC BASIC , TI BASIC dialects influenced by ALGOL 60 , Fortran FORTRAN II , JOSS influenced COMAL , Visual Basic , Visual Basic .NET , Realbasic , GRASS programming language GRASS BASIC is a family of General purpose programming language ... BASIC was designed in 1964 by John George Kemeny and Thomas Eugene Kurtz at Dartmouth College ... into the firmware of the machine. BASIC remains popular to this day in a handful of highly modified programming language dialect dialect s and new languages influenced by BASIC such as Microsoft Visual Basic . In 2006, 59 of developers for the .NET Framework used Visual Basic .NET as their only programming ... Basic programs to Linux Mono brings Visual Basic programs to Linux , LinuxDevices, 20 February 2007 ... s was an area of intense research during the 1960s and 70s. Origin main Dartmouth BASIC The original BASIC language was designed in 1964 by John George Kemeny John Kemeny and Thomas Eugene Kurtz Thomas ... B BASIC.html BASIC , The Jargon File ref BASIC was designed to allow students to write programs for the Dartmouth .... Initially, BASIC concentrated on supporting straightforward mathematical work, with matrix math matrix .... In the following years, as other dialects of BASIC appeared, Kemeny and Kurtz s original BASIC dialect became known as Dartmouth BASIC . Spread on minicomputers As a result of its free availability, knowledge of BASIC became relatively widespread for a computer language and BASIC was implemented ... Equipment Corporation DEC Programmed Data Processor PDP series and the Data General Nova . The BASIC language was also central to the HP Time Shared BASIC system in the late 1960s and early 1970s ... more details
The Ring may refer to tocright Film The Ring 1927 film The Ring 1927 film , a film by Alfred Hitchcock The Ring 1952 film The Ring 1952 film , a film by Kurt Neumann The Ring 1996 film The Ring 1996 film , a film by Armand Mastroianni Ring film Ring film , also known as Ringu or The Ring , a 1998 Japanese horror film by Hideo Nakata The Ring 2002 film The Ring 2002 film , a horror film by Gore Verbinski, a remake of the Japanese film The Rings or Zangha , a 1985 Iranian film Literature The Ring , a book by Daniel Keys Moran The Ring novel The Ring novel , by Danielle Steel The Ring , a children s book by John Updike The Ring magazine The Ring magazine , a boxing periodical The Ring poem The Ring poem , a poem by Heinrich Wittenwiler Television The Ring Angel The Ring Angel , a 2000 episode of Angel The Ring Chuck The Ring Chuck , a fictional spy organization in Chuck The Ring South Park The Ring South Park , a 2009 episode of South Park The Ring Yes, Dear The Ring Yes, Dear , an episode of Yes, Dear Other uses N rburgring or the Ring, a German racetrack The Ring rock formation , a rock formation in Bulgaria The Ring Terror s Realm , a 2000 video game Vaginal ring or the Ring, a hormonal contraceptive device The Ring album The Ring album , an album by Terri Hendrix See also One Ring , a fictional ring of power in J. R. R. Tolkien s Middle earth The Ring of the Nibelung or Der Ring des Nibelungen , a cycle of operas by Richard Wagner Ring disambiguation disambiguation da Ringen de The Ring fr The Ring id The Ring hu The Ring no The Ring pl The Ring ru sv The Ring ... more details
wiktionary ringRing may refer to Ring jewellery , a decorative ornament worn on fingers, toes, or around the arm or neck tocright Computing Ring computer security , a layer of protection in computer systems Ring data structure , also known as ring buffer or circular buffer Entertainment Ring video game Ring video game , a 1999 computer game Ring film Ring film , by Hideo Nakata Rings short film Rings short film , by Jonathan Liebesman Literature Ring Suzuki novel Ring Suzuki novel , a 1991 Japanese horror novel by Koji Suzuki Ring Stephen Baxter novel Ring Stephen Baxter novel , a 1994 science fiction novel by Stephen Baxter Logography Ring diacritic , as in m l Mathematics Ring geometric , or annulus, a circular shape Ring mathematics , an algebraic structure Ring of sets Medicine A sound in the ear s , which may be a symptom of tinnitus Music Ring song Ring song , by Japanese duo B z Ring The Connells album Ring The Connells album , 1993 Ring Miliyah Kato album Ring Miliyah Kato album Ring Gary Burton album Ring Gary Burton album , 1974 Ring band , a 1980s British band Der Ring des ... & the Glaser Brothers People Nick Ring born 1979 , martial artist Places Ireland Ring, County Waterford , a village United States Ring, Wisconsin , an unincorporated community Science Ring chemistry , a cyclic molecule Planetary ring , matter orbiting a planet RING finger domain , a protein structural domain Sports Championship ringRing boxing Ring wrestling Ring name Ring of Honor disambiguation ... Brass ring Claddagh ring Class ring Cock ring Engagement ring Piston ringRing telephone Ring road highway Rings local I.B.M. clubs Rings Sonic the Hedgehog Wedding ring See also The Ring disambiguation lookfrom ring disambiguation Category Rings bs Prsten vor ca Anell cv da Ring de Ring es Anillo desambiguaci n fa fr Ring gl Anel hom nimos ko he hr Prsten io Ringo lmo Anell nl Ring ja no Ring nn Ring nds Ring pl Pier cie pt Anel ru sr sv Ring th ... more details
complex is slow because it is in a higher energy state than the aromatic reactant. The loss of the chloride is fast, because the ring becomes aromatic again. Nucleophilic aromatic substitution reactions ...image Aromatic nucleophilic substitution.svg right 300px Aromatic nucleophilic substitution A nucleophilic aromatic substitution is a substitution reaction in organic chemistry in which the nucleophile displaces a good leaving group , such as a halide , on an aromaticring . There are 6 nucleophilic substitution mechanisms encountered with aromatic systems the S sub N sub Ar addition elimination mechanism image SNAr mechanism.svg 300px SNAr mechanism the aromatic SN1 mechanism encountered with diazonium salt s image Aromatic SN1 mechanism.svg 300px Aromatic SN1mechanism the benzyne mechanism image ... N sub Ar mechanism, where electron withdrawing group s activate the ring towards nucleophilic attack, for example if there are nitro functional group s positioned aromatic ortho substituent ortho or aromatic para substituent para to the halide leaving group. S sub N sub Ar reaction ... bond is in the plane of the ring as the carbon atom is trigonal. To attack from the back, the nucleophile would have to appear inside the benzene ring and invert the carbon atom in an absurd way. This reaction ... sub N sub 1 doesn t occur. The following is the reaction mechanism of a nucleophilic aromatic substitution of 2,4 dinitrochlorobenzene in a base chemistry basic aqueous solution. Image Nas1.png center 800px Nucleophilic aromatic substitution In this sequence the carbons are numbered clockwise from ... , the nonbonded electrons of the carbanion become bonded to the aromatic pi system which allows the ipso ... version of this reaction type. Nucleophilic aromatic substitution is not limited to arenes ... reactive when substituted in the aromatic ortho position or aromatic para position because then the negative ... Aromatic Substitution Freddy Tjosaas and Anne Fiksdahl Molecules journal Molecules 2006 , 11 ... more details
The term RingRing may refer to RingRing album RingRing album , an album by Bj rn & Benny, Agnetha & Anni Frid who would later become ABBA RingRing song RingRing song , a song by Bj rn & Benny, Agnetha & Anni Frid RingRing, a song by singer songwriter Mika singer Mika s which is a bonus track on his debut album Life in Cartoon Motion RingRing, a 14 year old girl in the Pucca TV series, see List of characters in Pucca disambig cs RingRing fr RingRing ko RingRing nl RingRing ... more details
With This Ring was a prime time panel show aired by the DuMont Television Network from January 21, 1951 to March 11, 1951. The show featured engagement engaged couples discussing marriage and marital problems. It was initially hosted by Bill Slater broadcaster Bill Slater , but the show quickly changed hosts to Martin Gabel , then left the air. ref http www.dumonthistory.tv a2.html DuMont historical website ref This show is not related in any way to a 15 minute television syndication syndicated program of the same name that aired weekly usually on Sundays on local stations throughout the U.S. for about 25 years beginning in the early 1970s. The latter program was a Roman Catholic produced show concerning the Church s doctrinal and moral positions on marriage and family life, and was produced at WJBK TV in Detroit . See also List of programs broadcast by the DuMont Television Network List of surviving DuMont Television Network broadcasts References reflist Bibliography David Weinstein, The Forgotten Network DuMont and the Birth of American Television Philadelphia Temple University Press , 2004 ISBN 1 59213 245 6 Alex McNeil, Total Television , Fourth edition New York Penguin Books , 1980 ISBN 0 14 024916 8 Tim Brooks and Earle Marsh, The Complete Directory to Prime Time Network TV Shows , Third edition New York Ballantine Books , 1964 ISBN 0 345 31864 1 External links http www.imdb.com title tt0331158 With This Ring at IMDB http www.dumonthistory.tv a2.html DuMont historical website Category DuMont Television Network shows Category 1950s American television series Category 1951 television series debuts Category 1951 television series endings Nonfiction tv prog stub ... more details
Electrophilic aromatic substitution EAS is an organic reaction in which an atom, usually hydrogen , appended to an aromaticringaromatic system is replaced by an electrophile . The most important reactions of this type that take place are aromatic nitration , aromatic halogenation , aromatic sulfonation , and acylation and alkylating Friedel Crafts reaction s. Basic reactions Aromatic nitration s to form ... jlac.19053430207 ref Basic reaction mechanism In the first step of the reaction mechanism for this reaction, the electron rich aromaticring which in the simplest case is benzene attacks the electrophile .... While electrophilic substituents usually withdraw electrons from the aromaticring and thus deactivate ... classes regarding electrophilic substitution activating and deactivating towards the aromaticring ... electron density from the aromaticring, though the positions most affected are again the ortho ... . Image BenzeneNitration.png Nitration of Benzene Aromatic sulfonation of benzene with fuming sulfuric acid gives benzenesulfonic acid. Image BenzeneSulfonation.png Sulfonation of Benzene Aromatic halogenation ... with an alkyl chloride Other reactions Other reactions that follow an electrophilic aromatic substitution pattern are a group of aromatic formylation reactions including the Vilsmeier Haack reaction , the Gattermann Koch reaction and the Reimer Tiemann reaction . Other electrophiles are aromatic ... a third substitution. This is especially the case with the use of catalysts . Substituted aromatic rings See also Arene substitution patterns Electrophiles may attack aromatic rings with functional ... positions. For a monosubstituted benzene, the ring carbon atom bearing the substituent is position 1 or aromatic ipso position ipso , the next ring atom is position 2 or Aromatic ortho substituent ortho , position 3 is Aromatic meta substituent meta and position 4 is Aromatic para substituent para ... the substitution by donating electrons into the ring system, by either inductive effect or resonance ... more details
Image L phenylalanine skeletal.png thumb phenylalanine Image L tryptophan skeletal.png thumb tryptophan Image L tyrosine skeletal.png thumb tyrosine Image Histidin Histidine.svg thumb histidine Image Thyroxine 2D skeletal.png thumb thyroxine Aromatic amino acids are amino acids that include an Aromaticity aromatic ring. Examples include Among 20 standard amino acids phenylalanine , tryptophan , histidine and tyrosine Others thyroxine See also Aromatic L amino acid decarboxylase Phenylalanine , histidine , and tryptophan are essential amino acids. Since they are not synthesized in the human body, they must be derived from the diet. Tyrosine is semi essential it can be synthesized, but only from phenylalanine. A lack of the enzyme phenylalanine hydroxylase used in tyrosine synthesis causes phenylketonuria . Many plants and microorganisms synthesize aromatic amino acids. Many herbicides inhibit aromatic acid synthesis, which is why they can be toxic to pets and humans. Clarify date July 2010 External links MeshName Aromatic Amino Acids MetabolismMap Category Amino acids Category Aromatic amino acids biochemistry stub zh ... more details
Orphan date January 2011 Chlorinated polycyclic aromatic hydrocarbons ClPAH s are a group of compounds comprising polycyclic aromatic hydrocarbon s with two or more aromaticring s and one or more chlorine atoms attached to the ring system. ClPAHs can be divided into two groups chloro substituted PAHs, which have one or more hydrogen atoms substituted by a chlorine atom, and chloro added ClPAHs, which have two or more chlorine atoms added to the molecule. ref name Nilsson1993 Nilsson, U. L., Oestman, C. E. Chlorinated polycyclic aromatic hydrocarbons method of analysis and their occurrence in urban air. Environ. Sci. Technol. 1993 27 9 1826&ndash 1831. doi 10.1021 es00046a010 ref They are products ... Trends and Relationships of Particulate Chlorinated Polycyclic Aromatic Hydrocarbons and Their Parent ... water solubility. ref Cerniglia, C. E. Biodegradation of polycyclic aromatic hydrocarbons. Biodegradation ..., M. Chlorinated Polycyclic Aromatic Hydrocarbons in the Atmosphere Seasonal Levels, Gas ... ref Sources of ClPAHs Chlorinated polycyclic aromatic hydrocarbons are generated by combustion ... Aromatic Hydrocarbons. The Scientific World. 2007 7 372&ndash 380. PMID 17334629 ref ClPAHs ... Aromatic Hydrocarbons in Environmental Samples from an Electronic Waste Recycling Facility and a Chemical ..., D. Analysis and structure prediction of chlorinated polycyclic aromatic hydrocarbons released ... and Profiles of Chlorinated and Brominated Polycyclic Aromatic Hydrocarbons in Waste Incinerators ... Kitazawa2006 The relative potency of three ring ClPAHs was found to increase with increasing degree ...., Ohura, T., Kannan K. Relative Potencies of Individual Chlorinated and Brominated Polycyclic Aromatic ... polycyclic aromatic hydrocarbons can exert their toxic effects is via the function of the aryl hydrocarbon ... T., Makino M. Occurrence, Profiles, and Photostabilities of Chlorinated Polycyclic Aromatic Hydrocarbons ... Chlorinated Polycyclic Aromatic Hydrocarbon Category Organochlorides Category Incineration Category ... more details
aromatic hydrocarbons PAH s , also known as poly aromatic hydrocarbons or polynuclear aromatic hydrocarbons , are potent atmospheric pollutants that consist of fused aromatic simple aromaticring ... comes from benzene , an aromatic hydrocarbon with a single, six membered ring. These can be benzene ... are aromatic compounds, the degree of aromaticity can be different for each ring segment. According .... Therefore in this molecule the outer rings are firmly aromatic while its central ring is less aromatic ...Image Polycyclic Aromatic Hydrocarbons.png thumb An illustration of typical polycyclic aromatic hydrocarbons .... C. title The Chemistry and Analysis of the Large Polycyclic Aromatic Hydrocarbons year 2000 doi 10.1080 10406630701268255 isbn 0471363545 publisher Wiley location New York journal Polycyclic Aromatic ... title Polycyclic Aromatic Hydrocarbons Occurrence in foods, dietary exposure and health effects publisher ... last Larsson first B. K. year 1983 title Polycyclic aromatic hydrocarbons in grilled food journal J ... toxfaqs tf.asp?id 121&tid 25 title Polycyclic Aromatic Hydrocarbons PAHs year 1996 publisher Agency ... motif is extended to large 2D sheets. Occurrence and pollution Polycyclic aromatic hydrocarbons ... conversion of natural product molecules, such as steroids, to aromatic hydrocarbons. They are also ... Aromatic Hydrocarbons place London publisher Imperial College Press isbn 1 86094 417 5 ref ... nomenclature for fused ring systems , are phenanthrene and anthracene , which both contain three fused aromatic rings. Smaller molecules, such as benzene , are not PAHs. PAHs may contain four , five ... that do not contain a complete benzene ring. The set of alternant PAHs is closely related to a set of mathematical ... regular hexagon s of identical size. PAHs containing up to six fused aromatic rings are often known as small PAHs, and those containing more than six aromatic rings are called large PAHs. Due ... spectra . These often possess many absorbance bands and are unique for each ring structure. Thus, for a set ... more details
Orphan date December 2008 The Aromatic transition state theory assumes that the minimum energy transition state for a pericyclic process must be aromatic . For 4n 2 sysyems 2,6,10... H ckel s rule Huckel transition states are proposed where the molecule is flat. In 4n sysyems 4,8,12... M bius aromaticity Mobius transition states are proposed which involve a twist or require a node to be aromatic. References Unreferenced date June 2009 Category Physical organic chemistry chem stub ... more details
enzyme Name aromatic amino acid transaminase EC number 2.6.1.57 CAS number 37332 38 0 IUBMB EC number 2 6 1 57 GO code 0008793 image width caption In enzymology , an aromatic amino acid transaminase EC number 2.6.1.57 is an enzyme that catalysis catalyzes the chemical reaction an aromatic amino acid 2 oxoglutarate math rightleftharpoons math an aromatic oxo acid L glutamate Thus, the two substrate biochemistry substrates of this enzyme are aromatic amino acid and 2 oxoglutarate , whereas its two product chemistry products are aromatic oxo acid and L glutamate . This enzyme belongs to the family of transferase s, specifically the transaminases , which transfer nitrogenous groups. The systematic name of this enzyme class is aromatic amino acid 2 oxoglutarate aminotransferase . Other names in common use include aromatic amino acid aminotransferase , aromatic aminotransferase , and ArAT . This enzyme participates in 6 metabolism metabolic pathways methionine metabolism , tyrosine metabolism , phenylalanine metabolism , phenylalanine, tyrosine and tryptophan biosynthesis , novobiocin biosynthesis , and alkaloid biosynthesis i . It employs one cofactor biochemistry cofactor , pyridoxal phosphate . Structural studies As of late 2007, 13 tertiary structure structures have been solved for this class of enzymes, with Protein Data Bank PDB accession codes PDB link 1AY4 , PDB link 1AY5 , PDB link 1AY8 , PDB link 2AY1 , PDB link 2AY2 , PDB link 2AY3 , PDB link 2AY4 , PDB link 2AY5 , PDB link 2AY6 , PDB link 2AY7 , PDB link 2AY8 , PDB link 2AY9 , and PDB link 3TAT . References reflist 1 cite journal author Mavrides C, Orr W date 1975 title Multispecific aspartate and aromatic amino acid aminotransferases in Escherichia coli journal J. Biol. Chem. volume 250 pages 4128&ndash 33 pmid 236311 issue 11 transferase stub Category EC 2.6.1 Category Pyridoxal phosphate enzymes Category Enzymes of known structure ... more details
Radical nucleophilic aromatic substitution or S sub RN sub 1 in organic chemistry is a type of substitution reaction in which a certain substituent on an aromatic compound is replaced by a nucleophile through an intermediary free radical species Image Radical nucleophilic aromatic substitution overview.png 300px center Radical nucleophilic aromatic substitution overview The substituent X is a halide and nucleophiles can be sodium amide , an alkoxide or a carbon nucleophiles such as an enolate . ref Phenomenon of radical anion fragmentation in the course of aromatic SRN reactions Roberto A. Rossi Acc. Chem. Res. 1982 15 6 pp 164 170 DOI 10.1021 ar00078a001 . ref In contrast to regular nucleophilic aromatic substitution , deactivating group s on the arene are not required. ref Rossi, R. A. Pierini, A. B. Santiago, A. N. Org. React. 1999 , 54 , 1.doi http dx.doi.org 10.1002 0471264180.or054.01 10.1002 0471264180.or054.01 ref This reaction type was discovered in 1970 by Bunnett and Kim ref Evidence for a radical mechanism of aromatic nucleophilic substitution Joseph F. Bunnett and Jhong Kook Kim J. Am. Chem. Soc. 1970 92 25 pp 7463 7464. DOI 10.1021 ja00728a037 ref and the abbreviation ... mechanism Image Radical nucleophilic aromatic substitution Mechanism.png 400px center Radical nucleophilic aromatic substitution Mechanism In this radical substitution the aryl halide 1 accepts an electron ... in a new type of nucleophilic aromatic substitution was invoked when the product distribution was compared between a certain aromatic chloride and an aromatic iodide in reaction with potassium ... Image Radical nucleophilic aromatic substitution Bunnett 1970.png 400px center Radical nucleophilic aromatic substitution Bunnett 1970 It now resembles ipso substitution with 1a forming preferentially ... the opposite. ref Alkali metal promoted aromatic nucleophilic substitution Joseph F. Bunnett and Jhong ... See also Birch reduction Nucleophilic aromatic substitution Category Free radical reactions Category ... more details
Orphan date February 2009 Primary aromatic amines PAA are a group of compounds. They might be added to plastic s during production. In animal testing the PAAs have been shown to be related to cancer , and one form of PAA has been found in unacceptable high levels in kitchen utensils made of black nylon in China . External links Danish Institute for Food and Veterinary Research , http www.dfvf.dk Admin Public DWSDownload.aspx?File Files 2FFiler 2FF C3 B8devaresikkerhed 2FMaterialer og genstande 2FPAA from black nylon cooking utentils 2004.pdf An acute case of primary aromatic amines migrating from cooking utensils , Memorandum for the Danish Veterinary and Food Administration, 2004 October 12 Category Materials chemistry stub ... more details
enzyme Name aromatic hydroxylamine O acetyltransferase EC number 2.3.1.56 CAS number 52660 15 8 IUBMB EC number 2 3 1 56 GO code 0047188 image width caption In enzymology , an aromatic hydroxylamine O acetyltransferase EC number 2.3.1.56 is an enzyme that catalysis catalyzes the chemical reaction N hydroxy 4 acetylaminobiphenyl N hydroxy 4 aminobiphenyl math rightleftharpoons math N hydroxy 4 aminobiphenyl N acetoxy 4 aminobiphenyl Thus, the two substrate biochemistry substrates of this enzyme are N hydroxy 4 acetylaminobiphenyl and N hydroxy 4 aminobiphenyl , whereas its two product chemistry products are N hydroxy 4 aminobiphenyl and N acetoxy 4 aminobiphenyl . This enzyme belongs to the family of transferase s, specifically those acyltransferase s transferring groups other than aminoacyl groups. The systematic name of this enzyme class is N hydroxy 4 acetylaminobiphenyl N hydroxy 4 aminobiphenyl O acetyltransferase . Other names in common use include aromatic hydroxylamine acetyltransferase , arylhydroxamate acyltransferase , arylhydroxamate N,O acetyltransferase , arylhydroxamic acid N,O acetyltransferase , arylhydroxamic acyltransferase , N,O acetyltransferase , and N hydroxy 2 acetylaminofluorene N O acyltransferase . References reflist 1 cite journal author Bartsch H, Dworkin C, Miller EC, Miller JA date 1973 title Formation of electrophilic N acetoxyarylamines in cytosoles from rat mammary gland and other tissues by transacetylation from the carcinogen N hydroxy 4 acetylaminobiphenyl journal Biochim. Biophys. Acta. volume 304 pages 42&ndash 55 pmid 4699998 issue 1 transferase stub Category EC 2.3.1 Category Enzymes of unknown structure it Aromatic idrossilammina O acetiltransferasi ... more details
unreferenced date October 2011 Saturate, Aromatic, Resin and Asphaltene SARA is an analysis method that divides crude oil components according to their polarizability and polarity. The saturate fraction consists of nonpolar material including linear, branched, and cyclic saturated hydrocarbons paraffins . Aromatics , which contain one or more aromatic rings, are slightly more polarizable. The remaining two fractions, resins and asphaltenes , have polar substituents. The distinction between the two is that asphaltenes are insoluble in an excess of heptane or pentane whereas resins are miscible with heptane or pentane . Metode description There are three main methods to obtain SARA results. One has lately emerged as the most popular. That technology is known as the Iatroscan TLC FID , it combines TLC with flame ionization detection TLC FID . It is referred to as IP 143. Other analysis giving SARA numbers might not correspont to the numbers obtained in IP 143. It is therefore always important to know the analysis method when comparing SARA numbers. See also Crude oil assay PONA number PIONA PNA analysis Category Petroleum ... more details
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