Stereochemistry, a subdiscipline of chemistry, involves the study of the relative spatial arrangement of atoms that form the structure of molecules and their manipulation.[1] The study of stereochemistry focuses on the relationships between stereoisomers, which by definition have the same molecular formula and sequence of bonded atoms (constitution), but differ in the geometric positioning of the atoms in space. For this reason, it is also known as 3D chemistry—the prefix "stereo-" means "three-dimensionality".[2]
Stereochemistry spans the entire spectrum of organic, inorganic, biological, physical and especially supramolecular chemistry. Stereochemistry includes methods for determining and describing these relationships; the effect on the physical or biological properties these relationships impart upon the molecules in question, and the manner in which these relationships influence the reactivity of the molecules in question (dynamic stereochemistry).
It was not until after the observations of certain molecular phenomena that stereochemical principles were developed. In 1815, Jean-Baptiste Biot's observation of optical activity marked the beginning of organic stereochemistry history. He observed that organic molecules were able to rotate the plane of polarized light in a solution or in the gaseous phase.[3] Despite Biot's discoveries, Louis Pasteur is commonly described as the first stereochemist, having observed in 1842 that salts of tartaric acid collected from wine production vessels could rotate the plane of polarized light, but that salts from other sources did not. This property, the only physical property in which the two types of tartrate salts differed, is due to optical isomerism. In 1874, Jacobus Henricus van 't Hoff and Joseph Le Bel explained optical activity in terms of the tetrahedral arrangement of the atoms bound to carbon. Kekulé used tetrahedral models earlier in 1862 but never published these; Emanuele Paternò probably knew of these but was the first to draw and discuss three dimensional structures, such as of 1,2-dibromoethane in the Giornale di Scienze Naturali ed Economiche in 1869.[4] The term "chiral" was introduced by Lord Kelvin in 1904. Arthur Robertson Cushny, Scottish Pharmacologist, in 1908, first offered a definite example of a bioactivity difference between enantiomers of a chiral molecule viz. (-)-Adrenaline is two times more potent than the (±)- form as a vasoconstrictor and in 1926 laid the foundation for chiral pharmacology/stereo-pharmacology[5][6] (biological relations of optically isomeric substances). Later in 1966, the Cahn-Ingold-Prelog nomenclature or Sequence rule was devised to assign absolute configuration to stereogenic/chiral center (R- and S- notation) [7] and extended to be applied across olefinic bonds (E- and Z- notation).
SignificanceEdit
Cahn–Ingold–Prelog priority rules are part of a system for describing a molecule's stereochemistry. They rank the atoms around a stereocenter in a standard way, allowing the relative position of these atoms in the molecule to be described unambiguously. A Fischer projection is a simplified way to depict the stereochemistry around a stereocenter.
Thalidomide exampleEdit
Thalidomide structures
Stereochemistry has important applications in the field of medicine, particularly pharmaceuticals. An often cited example of the importance of stereochemistry relates to the thalidomide disaster. Thalidomide is a pharmaceutical drug, first prepared in 1957 in Germany, prescribed for treating morning sickness in pregnant women. The drug was discovered to be teratogenic, causing serious genetic damage to early embryonic growth and development, leading to limb deformation in babies. Some of the several proposed mechanisms of teratogenicity involve a different biological function for the (R)- and the (S)-thalidomide enantiomers.[8] In the human body however, thalidomide undergoes racemization: even if only one of the two enantiomers is administered as a drug, the other enantiomer is produced as a result of metabolism.[9] Accordingly, it is incorrect to state that one stereoisomer is safe while the other is teratogenic.[10] Thalidomide is currently used for the treatment of other diseases, notably cancer and leprosy. Strict regulations and controls have been enabled to avoid its use by pregnant women and prevent developmental deformations. This disaster was a driving force behind requiring strict testing of drugs before making them available to the public.
a torsion angle between 0° and ±90° is called syn (s)
a torsion angle between ±90° and 180° is called anti (a)
a torsion angle between 30° and 150° or between –30° and –150° is called clinal
a torsion angle between 0° and 30° or 150° and 180° is called periplanar (p)
a torsion angle between 0° to 30° is called synperiplanar or syn- or cis-conformation (sp)
a torsion angle between 30° to 90° and –30° to –90° is called synclinal or gauche or skew (sc)[12]
a torsion angle between 90° to 150°, and –90° to –150° is called anticlinal (ac)
a torsion angle between ±150° to 180° is called antiperiplanar or anti or trans (ap).
Torsional strain results from resistance to twisting about a bond.
TypesEdit
Atropisomerism An energetic form of axial chirality. This form of chirality derives from differential substitution about a bond, commonly between two sp²-hydridized atoms.[13]
Cis–trans isomerism Also referred to as geometric isomers, these compounds have different configurations due to the inflexible structure of the molecule. Two requirements must be met for a molecule to present cis-trans isomerism:[14] 1. Rotation within the molecule must be restricted. 2. Two nonidentical groups must be on each doubly bonded carbon atom.
Conformational isomerism This form of isomerism is also referred to as conformers, rotational isomers, and rotamers. Conformational isomerism is produced by rotation about the Single bond.
Diastereomers These stereoisomers are non-image, non-identical. Diastereomers occur when the stereoisomers of a compound have differing configurations at corresponding stereocenters.[15]
Enantiomers Stereoisomers which are nonsuperimposable, mirror images.[16]
See alsoEdit
Wikiquote has quotations related to Stereochemistry.
^Ernest Eliel Basic Organic Stereochemistry ,2001ISBN0471374997; Bernard Testa and John Caldwell Organic Stereochemistry: Guiding Principles and Biomedicinal Relevance2014ISBN3906390691; Hua-Jie Zhu Organic Stereochemistry: Experimental and Computational Methods2015ISBN3527338225; László Poppe, Mihály Nógrádi, József Nagy, Gábor Hornyánszky, Zoltán Boros Stereochemistry and Stereoselective Synthesis: An Introduction2016ISBN3527339019
^"the definition of stereo-". Dictionary.com. from the original on 2010-06-09.
^Nasipuri, D (2021). Stereochemistry of Organic Compounds Principles and Applications (4th ed.). New Delhi: New Age International. p. 1. ISBN978-93-89802-47-4.
^Paternò, Emanuele (1869). "Intorno all'azione del percloruro di fosforo sul clorale". Giorn. Sci. Nat. Econ. 5: 117–122.
^Smith, Silas W. (2009-05-04). "Chiral Toxicology: It's the Same Thing…Only Different". Toxicological Sciences. 110 (1): 4–30. doi:10.1093/toxsci/kfp097. ISSN 1096-6080. PMID 19414517.
^Patočka, Jiří; Dvořák, Aleš (2004-07-31). "Biomedical aspects of chiral molecules". Journal of Applied Biomedicine. 2 (2): 95–100. doi:10.32725/jab.2004.011.
^Cahn, R. S.; Ingold, Christopher; Prelog, V. (April 1966). "Specification of Molecular Chirality". Angewandte Chemie International Edition in English. 5 (4): 385–415. doi:10.1002/anie.196603851. ISSN 0570-0833.
^Garrett, Reginald H.; Grisham, Charles M. (2005). Biochemistry (3rd ed.). Belmont, CA: Thomson Brooks/Cole. ISBN0-534-49033-6. OCLC 56058171.
^Caillet, Céline; Chauvelot-Moachon, Laurence; Montastruc, Jean-Louis; Bagheri, Haleh; French Association of Regional Pharmacovigilance Centers (November 2012). "Safety profile of enantiomers vs . racemic mixtures: it's the same?: Short report". British Journal of Clinical Pharmacology. 74 (5): 886–889. doi:10.1111/j.1365-2125.2012.04262.x. PMC3495153. PMID 22404187.
October 15, 2023
stereochemistry, subdiscipline, chemistry, involves, study, relative, spatial, arrangement, atoms, that, form, structure, molecules, their, manipulation, study, stereochemistry, focuses, relationships, between, stereoisomers, which, definition, have, same, mol. Stereochemistry a subdiscipline of chemistry involves the study of the relative spatial arrangement of atoms that form the structure of molecules and their manipulation 1 The study of stereochemistry focuses on the relationships between stereoisomers which by definition have the same molecular formula and sequence of bonded atoms constitution but differ in the geometric positioning of the atoms in space For this reason it is also known as 3D chemistry the prefix stereo means three dimensionality 2 The different types of isomers Stereochemistry focuses on stereoisomers Stereochemistry spans the entire spectrum of organic inorganic biological physical and especially supramolecular chemistry Stereochemistry includes methods for determining and describing these relationships the effect on the physical or biological properties these relationships impart upon the molecules in question and the manner in which these relationships influence the reactivity of the molecules in question dynamic stereochemistry Contents 1 History 2 Significance 2 1 Thalidomide example 3 Definitions 4 Types 5 See also 6 ReferencesHistory EditIt was not until after the observations of certain molecular phenomena that stereochemical principles were developed In 1815 Jean Baptiste Biot s observation of optical activity marked the beginning of organic stereochemistry history He observed that organic molecules were able to rotate the plane of polarized light in a solution or in the gaseous phase 3 Despite Biot s discoveries Louis Pasteur is commonly described as the first stereochemist having observed in 1842 that salts of tartaric acid collected from wine production vessels could rotate the plane of polarized light but that salts from other sources did not This property the only physical property in which the two types of tartrate salts differed is due to optical isomerism In 1874 Jacobus Henricus van t Hoff and Joseph Le Bel explained optical activity in terms of the tetrahedral arrangement of the atoms bound to carbon Kekule used tetrahedral models earlier in 1862 but never published these Emanuele Paterno probably knew of these but was the first to draw and discuss three dimensional structures such as of 1 2 dibromoethane in the Giornale di Scienze Naturali ed Economiche in 1869 4 The term chiral was introduced by Lord Kelvin in 1904 Arthur Robertson Cushny Scottish Pharmacologist in 1908 first offered a definite example of a bioactivity difference between enantiomers of a chiral molecule viz Adrenaline is two times more potent than the form as a vasoconstrictor and in 1926 laid the foundation for chiral pharmacology stereo pharmacology 5 6 biological relations of optically isomeric substances Later in 1966 the Cahn Ingold Prelog nomenclature or Sequence rule was devised to assign absolute configuration to stereogenic chiral center R and S notation 7 and extended to be applied across olefinic bonds E and Z notation Significance EditCahn Ingold Prelog priority rules are part of a system for describing a molecule s stereochemistry They rank the atoms around a stereocenter in a standard way allowing the relative position of these atoms in the molecule to be described unambiguously A Fischer projection is a simplified way to depict the stereochemistry around a stereocenter Thalidomide example Edit nbsp Thalidomide structuresStereochemistry has important applications in the field of medicine particularly pharmaceuticals An often cited example of the importance of stereochemistry relates to the thalidomide disaster Thalidomide is a pharmaceutical drug first prepared in 1957 in Germany prescribed for treating morning sickness in pregnant women The drug was discovered to be teratogenic causing serious genetic damage to early embryonic growth and development leading to limb deformation in babies Some of the several proposed mechanisms of teratogenicity involve a different biological function for the R and the S thalidomide enantiomers 8 In the human body however thalidomide undergoes racemization even if only one of the two enantiomers is administered as a drug the other enantiomer is produced as a result of metabolism 9 Accordingly it is incorrect to state that one stereoisomer is safe while the other is teratogenic 10 Thalidomide is currently used for the treatment of other diseases notably cancer and leprosy Strict regulations and controls have been enabled to avoid its use by pregnant women and prevent developmental deformations This disaster was a driving force behind requiring strict testing of drugs before making them available to the public Definitions EditFurther information Torsion angle nbsp syn anti peri clinalMany definitions that describe a specific conformer IUPAC Gold Book exist developed by William Klyne and Vladimir Prelog constituting their Klyne Prelog system of nomenclature a torsion angle of 60 is called gauche 11 a torsion angle between 0 and 90 is called syn s a torsion angle between 90 and 180 is called anti a a torsion angle between 30 and 150 or between 30 and 150 is called clinal a torsion angle between 0 and 30 or 150 and 180 is called periplanar p a torsion angle between 0 to 30 is called synperiplanar or syn or cis conformation sp a torsion angle between 30 to 90 and 30 to 90 is called synclinal or gauche or skew sc 12 a torsion angle between 90 to 150 and 90 to 150 is called anticlinal ac a torsion angle between 150 to 180 is called antiperiplanar or anti or trans ap Torsional strain results from resistance to twisting about a bond Types EditAtropisomerismAn energetic form of axial chirality This form of chirality derives from differential substitution about a bond commonly between two sp hydridized atoms 13 Cis trans isomerismAlso referred to as geometric isomers these compounds have different configurations due to the inflexible structure of the molecule Two requirements must be met for a molecule to present cis trans isomerism 14 1 Rotation within the molecule must be restricted 2 Two nonidentical groups must be on each doubly bonded carbon atom Conformational isomerismThis form of isomerism is also referred to as conformers rotational isomers and rotamers Conformational isomerism is produced by rotation about the Single bond DiastereomersThese stereoisomers are non image non identical Diastereomers occur when the stereoisomers of a compound have differing configurations at corresponding stereocenters 15 EnantiomersStereoisomers which are nonsuperimposable mirror images 16 See also Edit nbsp Wikiquote has quotations related to Stereochemistry Alkane stereochemistry Chiral resolution which often involves crystallization Chirality chemistry R S d l Chiral switch Skeletal formula Stereochemistry which describes how stereochemistry is denoted in skeletal formulae Solid state chemistry VSEPR theoryReferences Edit Ernest Eliel Basic Organic Stereochemistry 2001 ISBN 0471374997 Bernard Testa and John Caldwell Organic Stereochemistry Guiding Principles and Biomedicinal Relevance 2014 ISBN 3906390691 Hua Jie Zhu Organic Stereochemistry Experimental and Computational Methods 2015 ISBN 3527338225 Laszlo Poppe Mihaly Nogradi Jozsef Nagy Gabor Hornyanszky Zoltan Boros Stereochemistry and Stereoselective Synthesis An Introduction 2016 ISBN 3527339019 the definition of stereo Dictionary com Archived from the original on 2010 06 09 Nasipuri D 2021 Stereochemistry of Organic Compounds Principles and Applications 4th ed New Delhi New Age International p 1 ISBN 978 93 89802 47 4 Paterno Emanuele 1869 Intorno all azione del percloruro di fosforo sul clorale Giorn Sci Nat Econ 5 117 122 Smith Silas W 2009 05 04 Chiral Toxicology It s the Same Thing Only Different Toxicological Sciences 110 1 4 30 doi 10 1093 toxsci kfp097 ISSN 1096 6080 PMID 19414517 Patocka Jiri Dvorak Ales 2004 07 31 Biomedical aspects of chiral molecules Journal of Applied Biomedicine 2 2 95 100 doi 10 32725 jab 2004 011 Cahn R S Ingold Christopher Prelog V April 1966 Specification of Molecular Chirality Angewandte Chemie International Edition in English 5 4 385 415 doi 10 1002 anie 196603851 ISSN 0570 0833 Stephens TD Bunde CJ Fillmore BJ June 2000 Mechanism of action in thalidomide teratogenesis Biochemical Pharmacology 59 12 1489 99 doi 10 1016 S0006 2952 99 00388 3 PMID 10799645 Teo SK Colburn WA Tracewell WG Kook KA Stirling DI Jaworsky MS Scheffler MA Thomas SD Laskin OL 2004 Clinical pharmacokinetics of thalidomide Clin Pharmacokinet 43 5 311 327 doi 10 2165 00003088 200443050 00004 PMID 15080764 S2CID 37728304 Francl Michelle 2010 Urban legends of chemistry Nature Chemistry 2 8 600 601 Bibcode 2010NatCh 2 600F doi 10 1038 nchem 750 PMID 20651711 Anslyn Eric V and Dougherty Dennis A Modern Physical Organic Chemistry University Science 2005 1083 pp ISBN 1 891389 31 9 IUPAC Compendium of Chemical Terminology 2nd ed the Gold Book 1997 Online corrected version 2006 gauche doi 10 1351 goldbook G02593 Toenjes Sean T Gustafson Jeffrey L February 2018 Atropisomerism in medicinal chemistry challenges and opportunities Future Medicinal Chemistry 10 4 409 422 doi 10 4155 fmc 2017 0152 ISSN 1756 8919 PMC 5967358 PMID 29380622 13 2 Cis Trans Isomers Geometric Isomers Chemistry LibreTexts 2014 07 17 Retrieved 2022 11 27 Garrett Reginald H Grisham Charles M 2005 Biochemistry 3rd ed Belmont CA Thomson Brooks Cole ISBN 0 534 49033 6 OCLC 56058171 Caillet Celine Chauvelot Moachon Laurence Montastruc Jean Louis Bagheri Haleh French Association of Regional Pharmacovigilance Centers November 2012 Safety profile of enantiomers vs racemic mixtures it s the same Short report British Journal of Clinical Pharmacology 74 5 886 889 doi 10 1111 j 1365 2125 2012 04262 x PMC 3495153 PMID 22404187 Retrieved from https en wikipedia org w index php title Stereochemistry amp oldid 1144708310, wikipedia, wiki, book, books, library,
