dablink This article is about an organ stop . For other uses, see mixture disambiguation . A mixture is an organ stop , usually of Flue pipe Diapasons principal tone quality, that contains multiple ranks of organ pipe pipes . It is designed to be drawn with a combination of stops that forms a complete chorus for example, principals of Organ stop Pitch and length 8&prime , 4&prime , and 2&prime pitches . The mixture sounds the upper harmonics of each note of the keyboard. The individual pitches in the mixture are not perceived by the listener rather, they reinforce the fundamental pitches of the chorus, adding volume and brilliance to the sound. Historically, the mixture descends from the medieval Blockwerk concept, an organ in which there were no stops and all the ranks sounded simultaneously. Variables affecting tone color In addition to the standard concerns of organ flue pipe scaling voicing flue pipes , Most mixture stops include only octave and fifth pitch levels several historical ... and ninths. The number of ranks per note in a mixture commonly increases as one ascends the compass of the keyboard. A mixture exhibiting this trait is referred to as progressive . The frequency at which the various ranks in a mixture drop back by an interval or break as one ascends the compass determines to a great extent how the mixture sounds. If a mixture does not break, it is referred to as a harmonic mixture. Aristide Cavaill Coll built many examples of mixture stops labelled Plein jeux ... Diameter scale Halving ratio Parallel scaling of ranks Mixed scaling of ranks Mixture breaks The composition of Musical tuning pitches in a mixture may change or break several times across the compass of the keyboard. The breaks of a mixture involve the dropping out of a higher pitch at a given ... ordi pleinjeu pleinjeu.php?l en&f 0&url http hydraule.org bureau ordi pleinjeu src exemples Mixture ... Gemischte Stimmen fr Mixture orgue it Mistura organo ... more details
Infobox album See Wikipedia WikiProject Albums Name Victory Mixture Type studio Artist Willy DeVille Cover VictoryMixture.jpg Released January 1, 1990 France br December 28, 1990 United States U.S. Recorded Sea Saint Recording Studio, br New Orleans Genre Rhythm and blues R&B , Blues , Soul music Soul Length 32 12 Label Sky Ranch France br Orleans Records U.S. Producer Carlo Ditta Last album Miracle Willy DeVille album Miracle br 1987 This album Victory Mixture br 1990 Next album Backstreets of Desire br 1992 Album ratings rev1 Allmusic rev1score rating 4 5 ref Allmusic class album id r5588 pure url yes Allmusic review ref Automatically generated by DASHBot Victory Mixture is a 1990 album by Willy DeVille . The album consists of cover version s of New Orleans Rhythm and blues R&B and soul music soul classics by DeVille s musical idols. Trouser Press said about the album, A Roots revival rootsy covers collection, Victory Mixture provides a welcome antidote to Miracle Willy DeVille album Miracle s misguided modernity, making the most of the singer s relocation to New Orleans with backup from such local legends as Allen Toussaint , Eddie Bo and Dr. John . ref Editors 2006 http trouserpress.com entry.php?a mink deville Mink Deville Willy Deville. http trouserpress.com Trouser Press. Retrieved 3 6 08. ref Victory Mixture is unusual in that it was recorded without the use of overdubbing ... offering. The success of Victory Mixture in Europe ensured the label s continuing operation. Origins of Victory Mixture In 1988, Willy DeVille relocated from New York City New York to New Orleans. He ... of Victory Mixture A friend of mine Carlo Ditta who owns Orleans Records here in New Orleans approached ... an album at Sea Saint Studios titled Victory Mixture . I licensed it to my old friend, Phillippe ... it. ref name Interview Willy DeVille Other information Victory Mixture was produced by Carlo ... Ending Tour Band Bob Dylan s backup band in 2003 and 2004. Victory Mixture was also the first time ... more details
Wikify date September 2010 Self modeling mixture analysis is a class of data analysis techniques that are also termed as Blind signal separation or Blind source separation which are used to separate pure data components from additive mixture data. Examples Examples include the separation of pure Spectrum spectra and concentration profiles from a matrix of spectra made from mixtures of components with varying concentrations. Multivariate curve resolution Some classes of applications are also termed as multivariate curve resolution . Well known techniques include SIMPLISMA. ref Cite journal author1 Willem Windig author2 Jean Guilment year 1991 month July title Interactive Self Modeling Mixture Analysis journal Analytical Chemistry journal Analytical Chemistry volume 63 issue 14 pages 1425 1432 doi 10.1021 ac00014a016 authorlink1 Willem Windig authorlink2 Jean Guilment ref See also Mixture model References Reflist 2 Category Data analysis Statistics stub ... more details
Infobox Album See Wikipedia WikiProject Albums Name Instant Wigwam and Igloo Mixture Type Album Artist Go Kart Mozart Cover Released 1999 Recorded ??? Genre Rock music Rock Length 30 31 Label West Midlands Records Producer Reviews Allmusic Rating 4 5 Allmusic class album id r464985 pure url yes link NME Rating 7 10 http www.nme.com reviews go kart mozart 1754 link This album Instant Wigwam and Igloo Mixture br 1999 Next album Tearing Up The Album Charts br 2005 Instant Wigwam And Igloo Mixture is the debut album by the band Go Kart Mozart . It was released in 1999 on West Midlands Records, a subsidiary of Cherry Red . It was former Felt band Felt and Denim band Denim frontman Lawrence Hayward Lawrence s first album under the alias Go Kart Mozart. Track listing All songs written by Lawrence Hayward Lawrence Mandrax for Minx Cats We re Selfish and Lazy and Greedy Here Is a Song Sailor Boy City Synthesis Drinkin Um Bongo Mrs Back To Front and the Bull Ring Thing Hip Op Plead With the Man Wendy James Plug In City Depleted Soul She Tore It Up and Walked Away Today Wear Your Foghat With Pride Fluff on the Mallow Category 1999 albums 1990s rock album stub ... more details
In probability theory and statistics , a normal variance mean mixture with mixing probability density math g math is the continuous probability distribution of a random variable math Y math of the form math Y alpha beta V sigma sqrt V X, math where math alpha math and math beta math are real numbers and math sigma 0 math and random variables math X math and math V math are independence probability theory independent , math X math is normal distribution normally distributed with mean zero and variance one, and math V math is continuous probability distribution continuously distributed on the positive half axis with probability density function math g math . The conditional distribution of math Y math given math V math is thus a normal distribution with mean math alpha beta V math and variance math sigma 2 V math . A normal variance mean mixture can be thought of as the distribution of a certain quantity in an inhomogeneous population consisting of many different normal distributed subpopulations. It is the distribution of the position of a Wiener process Brownian motion with drift math beta math and infinitesimal variance math sigma 2 math observed at a random time point independent of the Wiener process and with probability density function math g math . An important example of normal variance mean mixtures is the generalised hyperbolic distribution in which the mixing distribution is the generalized inverse Gaussian distribution . The probability density function of a normal variance mean mixture with Mixture density mixing probability density math g math is math f x int 0 infty frac 1 sqrt 2 pi sigma 2 v exp left frac x alpha beta v 2 2 sigma 2 v right g v , dv math and its moment generating function is math M s exp alpha s , M g left beta s frac12 sigma 2 s 2 right , math where math M g math is the moment generating function of the probability distribution with density function math g math , i.e. math M g s E left exp s V right int 0 infty exp s v g v , dv. math See ... more details
For the confection dolly mixture Refimprove date September 2008 Infobox musical artist See Wikipedia WikiProject Musicians name Dolly Mixture image caption image size Only for images narrower than 220 pixels background group or band alias origin Cambridge , England genre Alternative rock Alternative br Post punk br New Wave music New Wave br Indie pop years active 1978 1984 label Chrysalis Records Chrysalis , Respond, br Dead Good Dollys Platters, Cordelia, Royal Mint associated acts Captain Sensible br Coming Up Roses br Saint Etienne band Saint Etienne br Birdie br Fruit Machine website current members past members Debsey Wykes br Rachel Bor br Hester Smith Dolly Mixture were a United Kingdom British post punk New Wave music new wave band formed in 1978 by bassist and vocalist Debsey Wykes b. 21 December 1960, Hammersmith, London, England , guitarist and vocalist Rachel Bor b. 16 May 1963, Wales , and drummer Hester Smith b. 28 October 1960, West Africa . They had a taste of Top 40 success performing backing vocals for the Captain Sensible s hit Wot and a UK 1 hit backing Sensible on his 1982 cover of Happy Talk song Happy Talk . Rachel Bor also featured on the Animus Loose Records ... . Dolly Mixture supported The Undertones on one of their first UK tours. The band also played ... had a hit with Happy Talk in 1982 featuring Dolly Mixture, credited as Dolly Mixtures on the single ... s video and following various appearances on the television show Top of the Pops , Dolly Mixture ... EP and the end of Dolly Mixture The 12 inch vinyl Fireside EP was released in 1984 on Cordelia Records ... music style. It was produced by Dolly Mixture and Andrew Fryer. The trio dissolved as a working band in 1984. Everything And More Dolly Mixture Box Set In July 2010 Dolly Mixture release a three ... Mixture champion, re releasing their untitled 1983 double album this time titled Demonstration Tapes ... Mixture Category All female bands Category British New Wave musical groups Category British post punk ... more details
oils by gas chromatography GC reveals a complex mixture containing many thousands of individual components ... the unresolved complex hydrocarbon mixture of a biodegraded crude oil using preparative capillary gas ... which distract attention from the underlying unresolved complex mixture UCM of hydrocarbons often ... more details
In statistics , the topic of location testing for Gaussian scale mixture distributions arises in some particular types of situations where the more standard Student s t test is inapplicable. Specifically, these cases allow location test tests of location to be made where the assumption that sample sample observations arise from populations having a normal distribution can be replaced by the assumption that they arise from a Gaussian scale mixture distribution. The class of Gaussian scale mixture distributions contains all symmetric stable distribution s, Laplace distribution s, logistic distribution s, and exponential power distributions, etc. ref Andrews, D. and C Mallows, C. 1974 Scale mixtures of normal distributions, Journal of the Royal Statistical Society , 36, 99 102 JSTOR 2984774 ref ref West, M. 1987 On scale mixtures of normal distributions , Biometrika , 74 3 , 646&ndash 648 doi 10.1093 biomet 74.3.646 ref Introduce t sup G sup sub n sub x , the counterpart of Student s t distribution for Gaussian scale mixtures. This means that if we test the null hypothesis that the center of a Gaussian scale mixture distribution is 0, say, then t sub n sub sup G sup x x 0 is the infimum of all monotone nondecreasing functions u x 1 2, x 0 such that if the critical values of the test are u sup &minus 1 sup 1 &minus , then the significance level is at most 1 2 for all Gaussian scale mixture distributions t sup G sup sub n sub x 1 &minus t sup G sup sub n sub &minus x ,for x 0 . An explicit formula for t sup G sup sub n sub x , is given in the papers in the references in terms of Student ... sub n sub t sup G sup sub n sub x , the Gaussian scale mixture counterpart of the standard ... with at least 95 probability for Gaussian scale mixture distributions. On the other hand, the 90 ... 1196283952 Student s t test for scale mixture errors , Optimality The Second Erich L. Lehmann ... more details
Infobox album Name Hironobu Kageyama Best Album 3 Mixture Type Greatest Hits Artist Hironobu Kageyama Cover Hironobu Kageyama 3 Mixture.PNG Released start date 1996 04 20 small COCC 13348 small Recorded Genre Jpop Language Japanese Language Japanese Length 65 89 Label Nippon Columbia Columbia Records Producer Reviews nihongo Hironobu Kageyama Best Album 3 Mixture 3 Mixture Kageyama Hironobu Besuto Arubamu Suri Mixture is a compilation album by Jpop artist Hironobu Kageyama . It was released on April 20, 1996 in Japan only. Any other information is to go in the album information section. Album Information This album is very sought after by Dragon Ball Z fan for its inclusion of English language English versions of the three Z series theme songs Cha La Head Cha La , We Gotta Power , and Boku tachi ha Tenshi datta . Track List Zenki ZENKI br Ch Kishin D ji Zenki, Raig Sh rin Super Demon Child Zenki, Salvation Saintly br Muteki no Kishin Fearful of the Unrivaled God Cha La Head Cha La English Version br Shu to te o Tsunag Let s Join Hand in Hand WILL POWER br Hikari no Will Power Willpower of Light br Eien no Yakusoku Earth of Eternity Saiky no Fusion br Saiky no Fy jon The Strongest Fusion We Gotta Power English Version Dokkan Beat Go Go br Go Go B rin Friends br Friends... Itsuka Doko ka de Friends...is Somewhere Sometime English Version br Boku tachi ha Tenshi datta English Version We Use to be Angels English Version Get the Win J br Makka na T kon Reddo Panch Downright Spirit of Fighting A Red Puncher br Danmatsuma ni Tsugu Hour of Death br Memor zu Yatsu no i Nai Yoru Memories An Evening Without Him External links http www10.ocn.ne.jp makutsu kageyama kage8.html Kageyama Complete listing Category Dragon Ball soundtrack albums Category 1996 greatest hits albums Category Columbia Records compilation albums ... more details
The Pfeiffer Effect is an optical phenomenon whereby the presence of an optically active compound influences the Optical rotatory dispersion optical rotation of a racemic mixture of a second compound. Racemic mixture s do not optical rotation rotate plane polarized light , but the equilibrium concentration of the two enantiomers can shift from unity in the presence of a strongly interacting chiral species. Paul Pfeiffer chemist Paul Pfeiffer , a student of Alfred Werner and inventor of the salen ligand , reported this phenomenon. ref cite journal author Paul Pfeiffer, Kurt Quehl title Aktivierung von Komplexsalzen in w riger L sung journal Chemische Berichte year 1932 volume 65 pages 560 565 doi 10.1002 cber.19320650410 issue 4 ref The first example of the effect is credited to Eligio Perucca , ref E. Perucca New observations and measurements upon optically active crystals NaClO sub 3 sub Nuovo Cimento 1919 , volume 18, pp. 112. ref who observed optical rotations in the visible part of the spectrum when crystals of sodium chlorate , which are Chirality chemistry chiral and colourless, were stained with a Racemic mixture racemic dye. ref Chemical & Engineering News, Vol. 86 No. 33, 18 August 2008, p. 38, Recognizing a Pioneer ref References references Category Polarization Category Stereochemistry optics stub ... more details
unreferenced date March 2010 Diastereomeric recrystallization is a method of chiral resolution of enantiomer s from a racemic mixture. It differs from asymmetric synthesis , which aims to produce a single enantiomer from the beginning, in that diastereomeric recrystallization separates two enantiomers that have already mixed into a single solution. The strategy of diastereomeric recrystallization involves two steps. The first step is to convert the enantiomers into diastereomers by way of a chemical reaction. A mixture of enantiomers may contain two isomers of a molecule with one chiral center. After adding a second chiral center in a determined location, the two isomers are still different, but they are no longer mirror images of each other rather, they become diastereomer s. In a prototypical example, a mixture of R and S enantiomers with one chiral center would become a mixture of R,S and S,S diastereomers. The R S notation is explained chirality chemistry Naming conventions here . The second step, once the diastereomers have formed, is to separate them using recrystallization chemistry recrystallization . This is possible because enantiomers have shared physical properties such as melting point and boiling point , but diastereomers have different physical properties, so they can be separated like any two different molecules. Chiral synthesis Category Stereochemistry ... more details
back to the racemicmixture by epimerization with hydrochloric acid in toluene. This process ...Chiral resolution in stereochemistry is a process for the separation of racemic compounds into their enantiomer s. ref cite journal title Resolution of chiral drugs author William H. Porter journal Pure Appl. Chem. volume 63 issue 8 pages 1119 1122 year 1991 url http www.iupac.org publications pac 1991 pdf 6308x1119.pdf doi 10.1351 pac199163081119 ref It is an important tool in the production of optically active drug s. Other terms with the same meaning are optical resolution and mechanical resolution . One disadvantage of chiral resolution of racemates compared to direct asymmetric synthesis of one of the enantiomers is that only 50 of a desired enantiomer is obtained. Several methods exist. Resolution by crystallization Typically 5 10 of all racemates are known to crystallize as mixtures of enantiopure crystals, so called conglomerates ref Enantiomers, racemates, and resolutions Jean Jacques, Andr Collet, Samuel H Wilen 1981 ISBN 0 471 08058 6 ref . Louis Pasteur was the first to conduct chiral resolution when he discovered the concept of optical activity in the first place by the manual separation of left handed and right handed tartaric acid crystals in 1849. Later in 1882 he went on to demonstrate that by Seed crystal seeding a supersaturation supersaturated solution of tartrate sodium ammonium tartrate with a d crystal on one side of the reactor and a l crystal on the opposite ... of resolution called spontaneous resolution has also been demonstrated with racemic methadone . ref ... purity can be obtained. Chiral resolving agents Derivatization of racemic compounds is possible ... in 1853 by resolving racemic tartaric acid with optically active cinchotoxine . One modern day method ... 913 doi 10.1021 op06011 ref Image RRRsynthesis.png center 400px RRR synthesis In one of its steps the racemic alcohol 1 is dissolved in a mixture of toluene and methanol to which solution is added optically ... more details
a racemic fraction of relatively high molecular weight eluting more slowly than the non associating ... performance liquid chromatographic anlaysis of racemic 14C labelled nicotine Separation of enantiomers ... more details
Drugbox verifiedrevid 448002978 IUPAC name 6 dimethylamino 4,4 di phenyl heptan 3 ol image Dimepheptanol.svg width 160 Clinical data tradename 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 legal UK Class A legal US Schedule I legal status routes of administration Pharmacokinetic data bioavailability protein bound metabolism elimination half life excretion Identifiers CAS number ATC prefix none ATC suffix PubChem DrugBank Ref drugbankcite correct drugbank DrugBank UNII Ref fdacite correct FDA UNII NNB4I01PA7 Chemical data C 21 H 29 N 1 O 1 molecular weight 311.46 g mol synonyms Dimepheptanol, Racemethadol Dimepheptanol Racemethadol is an opioid analgesic that is an analog chemistry analogue of methadone . Dimepheptanol is a mixture of two isomer s, methadol and methadol. These are also available separately, and this drug has three separate entries in many national and international lists of illegal drugs, which refer to the racemic mixture dimepheptanol, and the two optical isomers. Each of these isomers is itself a mixture of two isomers, and so there are in fact four isomers of dimepheptanol in total levo methadol, dextro methadol, levo methadol and dextro methadol. Image Methadol isomers.svg 400px The isomer levo methadol is the active metabolite of the long acting opioid substitute drug Levomethadyl Acetate , and has been much more widely used than methadol or the racemic mix dimepheptanol. Dimepheptanol has similar effects to other opioids, and produces analgesia, sedation and euphoria. Side effects can include itching , nausea and potentially serious respiratory depression which can be life threatening. References references Category Synthetic opioids Category Alcohols Category Mu opioid agonists analgesic stub sv Metadol ... more details
chembox verifiedrevid 399133300 ImageFile H dione.png ImageSize IUPACName Methyl 2 3 oxo 2 pentylcyclopentyl acetate OtherNames Hedione br Kharismal br Cepionate Section1 Chembox Identifiers CASNo 24851 98 7 PubChem 24901528 SMILES O C OC CC1C C O CC1 CCCCC Section2 Chembox Properties C 13 H 22 O 3 Appearance Clear to pale yellow oily liquid MeltingPt BoilingPtC 110 Solubility Section3 Chembox Hazards MainHazards FlashPt 113 C Autoignition Methyl dihydrojasmonate is an ester and a diffusive aroma compound , with the smell vaguely similar to jasmine . In racemic mixture s the odor is floral and citrus while epimerized mixtures exhibit a dense fatty floral odor with odor recognition thresholds of 15 parts per billion. ref Citation first John C. last Leffingwell publisher Leffingwell & Associates year 2001 title The Methyl dihydrojasmonates ref The compound is also known as Hedione References reflist ester stub Category Flavors Category Methyl esters fa fr H dione ... more details
Drugbox IUPAC name 17 methylmorphinan 3 ol image Racemorphan.svg width 250 Clinical data tradename pregnancy category legal status routes of administration Pharmacokinetic data bioavailability protein bound metabolism elimination half life excretion Identifiers CAS number 297 90 5 CAS supplemental br CAS 5985 35 3 Hydrobromide HBr ATC prefix ATC suffix PubChem ChemSpiderID 16736212 UNII Ref fdacite correct FDA UNII V7R79HN3XD Chemical data C 17 H 23 N 1 O 1 molecular weight 257.37 g mol Racemorphan is the racemic mixture of the two stereoisomer s of 17 methylmorphinan 3 ol, each with differing pharmacology and therapeutic effect effect s Dextrorphan A dissociative drug dissociative hallucinogen NMDA receptor antagonist and cough suppressant . Levorphanol A potent pharmacology potent opioid analgesic . See also Methorphan Morphinan References Reflist 2 Antitussives Hallucinogens Analgesics Anesthetics Cholinergics Glutamatergics Opioids Serotonergics Category Morphinans Category Opioids Category Phenols nervous system drug stub respiratory system drug stub ru fi Rasemorfaani ... more details
chembox verifiedrevid 414206176 ImageFile tropic acid.png ImageSize 200px IUPACName 3 Hydroxy 2 phenylpropanoic acid OtherNames 2 Phenylhydracrylic acid Tropate Section1 Chembox Identifiers CASNo 529 64 6 PubChem 10726 SMILES C1 CC C C C1 C CO C O O Section2 Chembox Properties C 9 H 10 O 3 Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Tropic acid is a chemical with IUPAC name 3 hydroxy 2 phenylpropanoic acid and condensed structural formula HOCH sub 2 sub CH phenyl Ph COOH. It is a laboratory reagent used in the chemical synthesis of atropine and hyoscyamine . Tropic acid is a chirality chemistry chiral substance, existing as either a racemic mixture or as a single enantiomer . Uses Tropic acid is reacted with tropine product of tropinone to produce atropine. Category Hydroxy acids Category Propionic acids organic compound stub fa fr Acide tropique nl Tropinezuur ... more details
racemic and single enantiomer form. class wikitable Racemicmixture Single enantiomer Amphetamine ... markedly different effects Thalidomide Thalidomide is racemic. One enantiomer is effective against ... more details
is proposed whereby enantioenriched clusters are formed from a non racemicmixture already ... homochiral D Ser sub 8 sub and L Ser sub 8 sub . In another experiment cluster formation of a racemicmixture with deuterium enriched L serine results in a product distribution with hardly any 50 ... concentration of L serine than in the original mixture. A cycle can be maintained in which each turn ... more details
the syn pair . One study examined the biocatalysis biocatalytic acetylation of a racemic 8 aminotetrahydroquinoline ... 2007 The enzyme only converts the R enantiomer and, in regular kinetic resolution, a 50 50 mixture ... the racemic enamine 3 which can be hydrolyzed back to the amine. In a second manifestation of the DKR method, both enantiomers of a racemic pair form a prochiral intermediate or a meso compound . An example ... between two sets of racemic compounds via a kinetic pathway. This kinetic resolution is described ... sets of racemates, only one set of racemates is used and resolved using a quasi enantiomeric mixture ... more details
, which is enantiopure and therefore is given in doses that are exactly 1 2 of the older, racemicmixture ... manufacturers to take drugs that were originally marketed as a racemicmixture and market ... drugs are separately patentable from the racemicmixture. ref http www.ema.europa.eu ema index.jsp?curl ... although the polarized light can be considered an asymmetric medium . A mixture of equal parts of an optically active isomer and its enantiomer is termed racemic and has zero net rotation of plane ... inactive because they are equal and opposite to each other. Examples File Mecoprop racemic dimer from .... the antidepressant drugs escitalopram and citalopram . Citalopram is a racemate 1 1 mixture of S citalopram .... The first is known as chiral resolution. This method involves preparing the compound in racemic form ... is the synthesis of one enantiomer from a racemic precursor molecule utilizing both enantiomers. Thus ... enantiomers are active. Or, it may be that only one is active, in which case separating the mixture ... more details
Unreferenced stub auto yes date December 2009 Drugbox verifiedrevid 443652033 IUPAC name RS 2 2 oxopyrrolidin 1 yl butanamide image Etiracetam structure.svg width 106px image2 Etiracetam3d.png imagename 1 1 mixture racemate drug name Etiracetam Clinical data tradename pregnancy category legal status Unscheduled US routes of administration Oral Pharmacokinetic data bioavailability metabolism excretion Identifiers CAS number 33996 58 6 ATC prefix none PubChem 59708 DrugBank Ref drugbankcite correct drugbank ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 53863 UNII Ref fdacite correct FDA UNII 230447L0GL Chemical data C 8 H 14 N 2 O 2 molecular weight 170.209 g mol smiles CCC C O N N1CCCC1 O InChI 1 C8H14N2O2 c1 2 6 8 9 12 10 5 3 4 7 10 11 h6H,2 5H2,1H3, H2,9,12 InChIKey HPHUVLMMVZITSG UHFFFAOYAH StdInChI Ref stdinchicite correct chemspider StdInChI 1S C8H14N2O2 c1 2 6 8 9 12 10 5 3 4 7 10 11 h6H,2 5H2,1H3, H2,9,12 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey HPHUVLMMVZITSG UHFFFAOYSA N Etiracetam is a nootropic drug of the racetam family. It is racemic its biologically active enantiomer ic form is levetiracetam . See also Piracetam Racetams Category Racetams Category Pyrrolidones Category Amides nervous system drug stub ... more details
, which is a racemicmixture called tocopheryl acetate all rac alpha tocopheryl acetate . This mix ... dl,dl,dl alpha tocopheryl acetate . However, 1 IU of this racemicmixture is not now considered equivalent ... IU s of the racemicmixture to milligrams of equivalent RRR using 1 IU racemicmixture 0.45 milligrams ... more details
Drugbox verifiedrevid 448239916 IUPAC name 3 methyl 4 morpholin 4 yl 2,2 diphenyl 1 pyrrolidin 1 yl butan 1 one image Racemoramide.svg Clinical data tradename pregnancy category legal US Schedule I routes of administration Pharmacokinetic data bioavailability metabolism excretion Identifiers CAS number 545 59 5 ATC prefix none ATC suffix DrugBank Ref drugbankcite correct drugbank UNII Ref fdacite correct FDA UNII L3J8QT828G Chemical data C 25 H 32 N 2 O 2 molecular weight 392.534 g mol smiles Racemoramide International Nonproprietary Name INN , British Approved Name BAN , or simply moramide , is a opioid analgesic and a racemic mixture of the substances dextromoramide the active component and levomoramide which is inactive , two enantiomer s of a chirality chemistry chiral molecule . ref name GanellinTriggle1997 cite book author1 C. R Ganellin author2 D. J Triggle author3 F.. Macdonald title Dictionary of pharmacological agents url http books.google.com books?id A0THacd46ZsC&pg PA1375 accessdate 29 November 2011 year 1997 publisher CRC Press isbn 978 0 412 46630 4 page 1375 ref References Reflist Analgesics Opioids Category Analgesics Category Morpholines Category Opioids Category Propionamides Category Pyrrolidines analgesic stub ... more details
The enantiomeric excess of a substance is a measure of how pure it is. In this case, the impurity is the undesired enantiomer the opposite handed mirror image of a chiral compound . Definition Enantiomeric excess is defined as the absolute difference between the mole fraction of each enantiomer ref GoldBookRef file E02070 year 1996 title Enantiomer excess ref math ee F F math where math F F 1 math In practice, it is most often expressed as a percent enantiomeric excess . math ee alpha obs alpha max times 100 math 1 The enantiomeric excess can be determined in another way if we know the amount of each enantiomer produced. If one knows the moles of each enantiomer produced then math ee R S R S times 100 math 2 math R math and math S math are the respective fractions of enantiomers in a mixture such that math R S 1 math Enantiomeric excess is used as one of the indicators of the success of an asymmetric synthesis . For mixtures of diastereomer s, there are analogous definitions and uses for diastereomeric excess and percent diastereomeric excess . As an example, a sample with 70 of R isomer and 30 of S will have an enantiomeric excess of 40 . This can also be thought of as a mixture of 40 pure R with 60 of a racemic mixture which contributes 30 R and 30 S to the overall composition . A non racemic mixture of two enantiomers will have a net optical rotation . It is possible to determine the specific rotation of the mixture and, with knowledge of the specific rotation of the pure enantiomer, the optical purity can be determined. ref GoldBookRef file O04310 year 1996 title Optical purity ref File Optical Purity V.1.svg left 300px Optical purity br Ideally, the contribution of each component of the mixture to the total optical rotation is directly proportional to its mole fraction, and as a result the numerical value of the optical purity is identical to the enantiomeric excess. This has led to informal use the two terms as interchangeable, especially because optical purit ... more details
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