[L. rectus right] a stereodescriptor used to specify the absolute configuration of compounds having asymmetric carbon atoms. The four different substituents at the asymmetric carbon atom are ranked according to the Cahn-Ingold-Prelog sequence rules; then, looking at the molecule with the lowest ranking substituent pointing directly away from the viewer, if the other three substituents are in clockwise order going from highest to lowest ranked, the configuration is R; otherwise S>. Example: L-threonine is (2S:3R)-2-amino-3-hydroxybutanoic acid.

Medical dictionary. 2011.

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  • R — is the eighteenth letter of the modern Latin alphabet. Its name in English is spelled ar (IPAEng|ɑr; pronounced IPA| [ɑː] or IPA| [ɑɹ] ). [ R Oxford English Dictionary, 2nd edition (1989); ar, op. cit.] HistoryThe original Semitic letter was… …   Wikipedia

  • R — (ĕr) r, lat. R, r, ist als Sprachlaut wie l eine Liquida. Es kann verschieden ausgesprochen werden und zerfällt in drei Hauptarten: das zerebrale r, besonders im Englischen gebräuchlich, entstehend durch Aufbiegung des vordern Zungensaums nach… …   Meyers Großes Konversations-Lexikon

  • R. — R. Studioalbum von R. Kelly Veröffentlichung 1998 Label Jive Format …   Deutsch Wikipedia

  • R — R: R  латинская буква. R  язык программирования. В науке: В физике: R в физике: обозначение постоянной Ридберга. R универсальная газовая постоянная. R в физике: обозначение электрического сопротивления. В математике: R в математике:… …   Википедия

  • R — R, der achtzehente Buchstab des Deutschen Alphabetes und der vierzehente unter den Consonanten, welcher mit einer zitternden Bewegung der Zungenspitze an dem Gaumen ausgesprochen wird, daher er auch zu den Zungenbuchstaben gehöret. Man rechnet… …   Grammatisch-kritisches Wörterbuch der Hochdeutschen Mundart

  • R — ([aum]r). R, the eighteenth letter of the English alphabet, is a vocal consonant. It is sometimes called a semivowel, and a liquid. See Guide to Pronunciation, [sect][sect] 178, 179, and 250 254. R is the dog s letter and hurreth in the sound. B …   The Collaborative International Dictionary of English

  • Ŕ — (minuscule: unicode|ŕ) is a letter of the Slovak and Lower Sorbian alphabets. It is formed from R with the addition of an acute. lovakIt is used in Slovak to represent : IPA| [ r̩ː ] .Lower SorbianIt is used in Lower Sorbian to represent palatal… …   Wikipedia

  • R* — or R* can mean the following:*Rockstar Games uses R* as its symbol* R* , the symbol for an ecological concept developed by G. David Tilman to explain the minimum concentration to which an organism can reduce a resource. R is the symbol he uses… …   Wikipedia

  • R++ — is a rule based programming language based on C++. The United States patent describes R++ as follows::The R++ extension permits rules to be defined as members of C++ classes. The programming system of the invention takes the classes with rules… …   Wikipedia

  • R — R, der 18. Buchstabe unsers Alphabets, zu den Liquiden gehörig. Als Abkürzung R und r = Roma, Romanus, regia, regnum etc.; auf Rezepten = recĭpe (lat., nimm); in der Mathematik = rechter Winkel; bei Temperaturangaben = Réaumur; auf Taschenuhren… …   Kleines Konversations-Lexikon

  • R. — R. is an abbreviation of the Latin word Rex (King) or Regina (Queen) and is used as notation in British criminal prosecutions to mean the Crown or the State , which is represented by the current monarch.It is often seen written as R. v Defendant… …   Wikipedia

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