DOCSLIB.ORG

Optical Activity - Chirality

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Optical Activity - Chirality Optical Activity - Chirality A carbon atom bddbonded to four differen t groups could ldlead tooptical activit yand is called a stereogenic center. CH3 H CH2CH3 HO In general organic compounds, which lack a plane of symmetry are optical active and are called chiral compounds. OH OH OH OH Achiral Chiral Optically active compounds exist as enantiomers, which are mirror images of each other Optical Activity - Chirality cis-1,2-dichlorocyclohexane If enantiomers are in equilibrium with each other throughring flipping, one enantiomer cannot be separated from the other. Cl Cl Cl Cl Ring flip 120° Cl Cl Optical Activity - Chirality trans-1,2-dichlorocyclohexane Enantiomers Cl Cl Cl Cl Ring flip Cl Cl Cl Cl Absolute Configuration: Cahn-Inglod-Prelog Rule Substituents on a chiral carbon are assigned priority, based primarily on the atomic number of the atom directly bonded to the carbon atom Atom or Reason for Priority: First Point of Difference Group (Atomic numbers) -I iodine (53) -Br bromine (35) -Cl chlorine (17) -SH sulfur (16) -OH oxygen (8) -NH2 nitrogen (7) O -COH carbon to oxygen, oxygen, then oxygen (6 ->8, 8, 8) O -CNH2 carbon to oxygen, oxygen, then nitrogen (6 ->8, 8, 7) O -CH carbon to oxygen, oxygen, then hydrogen (6 ->8, 8, 1) -CH2 OH carbon to oxygen (6 -> 8) -CH2 NH2 carbon to nitrogen (6 -> 7) -CH2 CH3 carbon to carbon (6->6) -CH2 H carbon to hydrogen (6 -> 1) -H hydrogen (1) Absolute Configuration: R and S Notations Each stereogenic center is assigned a configuration , based on the following rules 1. Use the Cahn-Ingold-Prelog priority rules to assign priority (one through four) to the four groups on the chiral carbon atom. 2. Orient the molecule so that the lowest priority atom is in the back (away from you). Look at the remaining three groups of priority 1-3. If the remaining three groups are arranged so that the priorities 1→2→3areinaclockwise fashion, then assign the chiral center as R (“rectus” or right). If the remaining three groups are arranged 1→2→3ina counterclockwise manner, then assign the chiral center as S (“sinister” or left) Orienting a Tetrahedron – The Double Switch Interchanging any two groups inverts the stereochemistry. So switch the lowest priority group to the desired position. Then switch any other two groups. The “double-switch” does not change the stereochemistry. Fischer Projections Representation of a three-dimensional molecule as a flat structure. A tetrahedral carbon is represented using just two crossed lines: Horizontal line is coming out of the plane of the page (towards you) and vertical line is going back behind the plane of the paper (away from you) F F I Cl I Br Cl Br H H H C OH OH 3 HOOC COOH CH3 Manipulation of Fischer Projections Rotating a Fischer projection by 180° retains the configuration Rotating aFischer ppjrojection byy 90° inverts the configuration If one ggproup of aFischer ppjrojection is held steady, the other three ggproups can be rotated clockwise or counterclockwise without altering the configuration. Assigning R and S Configurations to Fischer Projections 1. Assign priorities to the four substitutents according to the Cahn-Ingold-Prelog rules 2. Perform the two allowed manipulations of the Fischer projection to place the lowest priority group at the top (or bottom). 3. If the priority of the groups 1→2→3 are clockwise then assign the center as R, if 1→2→3 are counterclockwise then assign the center as S. place at the top 2CH2CH3 4H 4H OH1 1HO CH2CH32 3CH3 3CH3 hold steady clockwise - R Molecules with more than one Stereocenter If a molecule has one stereocenter it exists as R and S isomers, which are enantiomers. If a molecule has two stereocenters, each of them can exist as R and S, independent of the other center. The maximum number of stereoisomers for a molecule having n stereocenters is 2n 2,3-dibromopentane has 2 chiral centers. There can be 4 stereoisomers, which are (2R,3R) (2R,3S) (2S,3R) (2S,3S) (2R,3R) and (2S,3S) isomers are enantiomers, so are (2R,3S) and (2S,3R)isomers (2R,3R) isomer is a diastereomer of (2R,3S) and (2S,3R)isomers Similarly, (2S,3S) isomer is a diastereomer of (2R,3S) and (2S,3R)isomers Stereoisomers of 2,3-dibromopentane CH3 CH3 R S Br H H Br S R Br H H Br rs CH CH CH CH ee 2 3 2 3 astereom ii CH3 CH3 D S R H Br Br H S R Br H H Br CH2CH3 CH2CH3 Enantiomers Stereoisomers of 2,3-dibromobutane CH3 CH3 R S Br H H Br Here the RS and SR isomers are S R identical molecules. Br H H Br This diastereomer is called ‘meso’ and CH3 CH3 is an achiral molecule This results from the plane of CH3 CH3 symmetry present in this isomer. S R H Br Br H Thus, although the maximum number S R Br H H Br of stereoisomers can never be more than 2n, the actual number could be CH3 CH3 lower. Enantiomers Meso diastereomers HO H H OH HO OH HO H H OH H H HO H HOOC COOH Cl Cl Cl Cl Chirality Without a Stereocenter - Biphenyls If X-is a small group, the single bond connecting the two phenyl rings would undergo easy rotation and result in racemization Chirality resulting from restricted rotation about a single bond is called Atropisomerism Chira lity With out a Stereocenter - Allenes Chira lity With out a Stereocenter – SiSpiro Compoun ds.
Load more

Recommended publications
  • – with Novozymes Enzymes for Biocatalysis
    Biocatalysis Pregabalin case study Smarter chemical synthesis – with Novozymes enzymes for biocatalysis The new biocatalytic route results in process improvements, reduced organic solvent usage and substantial reduction of waste streams in Pregabalin production. Introduction Biocatalysis is the application of enzymes to replace chemical Using Lipolase®, a commercially available lipase, rac-2- catalysts in synthetic processes. In recent past, the use of carboxyethyl-3-cyano-5-methylhexanoic acid ethyl ester biocatalysis has gained momentum in the chemical and (1) can be resolved to form (S)-2-carboxyethyl-3-cyano-5- pharmaceutical industries. Today, it’s an important tool for methylhexanoic acid (2). Compared to the first-generation medicinal, process and polymer chemists to develop efficient process, this new route substantially improves process and highly attractive organic synthetic processes on an efficiency by setting the stereocenter early in the synthesis and industrial scale. enabling the facile racemization and reuse of (R)-1. The biocatalytic process for Pregabalin has been developed It outperforms the first-generation manufacturing process also by Pfizer to boost efficiency in Pregabalin production using by delivering higher yields of Pregabalin and by resulting in Novozymes Lipolase®. substantial reductions of waste streams, corresponding to a 5-fold decrease in the E-Factor from 86 to 17. Development of the biocatalytic process for Pregabalin involves four stages: • Screening to identify a suitable enzyme • Performing optimization of the enzymatic reaction to optimize throughput and reduce enzyme loading • Exploring a chemical pathway to preserve the enantiopurity of the material already obtained and lead to Pregabalin, and • Developing a procedure for the racemization of (R)-1 Process improvements thanks to the biocatalytic route Pregabalin chemical synthesis H Knovenagel CN condensation cyanation KOH 0 Et02C CO2Et Et02C CO2Et Et02C CO2Et CNDE (1) CN NH2 1.
    [Show full text]
  • A Reminder… Chirality: a Type of Stereoisomerism
    A Reminder… Same molecular formula, isomers but not identical. constitutional isomers stereoisomers Different in the way their Same connectivity, but different atoms are connected. spatial arrangement. and trans-2-butene cis-2-butene are stereoisomers. Chirality: A Type of Stereoisomerism Any object that cannot be superimposed on its mirror image is chiral. Any object that can be superimposed on its mirror image is achiral. Chirality: A Type of Stereoisomerism Molecules can also be chiral or achiral. How do we know which? Example #1: Is this molecule chiral? 1. If a molecule can be superimposed on its mirror image, it is achiral. achiral. Mirror Plane of Symmetry = Achiral Example #1: Is this molecule chiral? 2. If you can find a mirror plane of symmetry in the molecule, in any achiral. conformation, it is achiral. Can subject unstable conformations to this test. ≡ achiral. Finding Chirality in Molecules Example #2: Is this molecule chiral? 1. If a molecule cannot be superimposed on its mirror image, it is chiral. chiral. The mirror image of a chiral molecule is called its enantiomer. Finding Chirality in Molecules Example #2: Is this molecule chiral? 2. If you cannot find a mirror plane of symmetry in the molecule, in any conformation, it is chiral. chiral. (Or maybe you haven’t looked hard enough.) Pharmacology of Enantiomers (+)-esomeprazole (-)-esomeprazole proton pump inhibitor inactive Prilosec: Mixture of both enantiomers. Patent to AstraZeneca expired 2002. Nexium: (+) enantiomer only. Process patent coverage to 2007. More examples at http://z.umn.edu/2301drugs. (+)-ibuprofen (-)-ibuprofen (+)-carvone (-)-carvone analgesic inactive (but is converted to spearmint oil caraway oil + enantiomer by an enzyme) Each enantiomer is recognized Advil (Wyeth) is a mixture of both enantiomers.
    [Show full text]
  • Chirality in Chemical Molecules
    Chirality in Chemical Molecules. Molecules which are active in human physiology largely function as keys in locks. The active molecule is then called a ligand and the lock a receptor. The structures of both are highly specific to the degree that if one atom is positioned in a different position than that required by the receptor to be activated, then no stimulation of the receptor or only partial activation can take place. Again in a similar fashion if one tries to open the front door with a key that looks almost the same than the proper key for that lock, one will usually fail to get inside. A simple aspect like a lengthwise groove on the key which is on the left side instead of the right side, can mean that you can not open the lock if your key is the “chirally incorrect” one. The second aspect to understand is which molecules display chirality and which do not. The word chiral comes from the Greek which means “hand-like”. Our hands are mirror images of each other and as such are not identical. If they were, then we would not need a right hand and left hand glove. We can prove that they are not identical by trying to lay one hand on top of the other palms up. When we attempt to do this, we observe that the thumbs and fingers do not lie on top of one another. We say that they are non-super imposable upon one another. Since they are not the same and yet are mirror images of each other, they are said to exhibit chirality.
    [Show full text]
  • Chapter 4: Stereochemistry Introduction to Stereochemistry
    Chapter 4: Stereochemistry Introduction To Stereochemistry Consider two of the compounds we produced while finding all the isomers of C7H16: CH3 CH3 2-methylhexane 3-methylhexane Me Me Me C Me H Bu Bu Me Me 2-methylhexane H H mirror Me rotate Bu Me H 2-methylhexame is superimposable with its mirror image Introduction To Stereochemistry Consider two of the compounds we produced while finding all the isomers of C7H16: CH3 CH3 2-methylhexane 3-methylhexane H C Et Et Me Pr Pr 3-methylhexane Me Me H H mirror Et rotate H Me Pr 2-methylhexame is superimposable with its mirror image Introduction To Stereochemistry Consider two of the compounds we produced while finding all the isomers of C7H16: CH3 CH3 2-methylhexane 3-methylhexane .Compounds that are not superimposable with their mirror image are called chiral (in Greek, chiral means "handed") 3-methylhexane is a chiral molecule. .Compounds that are superimposable with their mirror image are called achiral. 2-methylhexane is an achiral molecule. .An atom (usually carbon) with 4 different substituents is called a stereogenic center or stereocenter. Enantiomers Et Et Pr Pr Me CH3 Me H H 3-methylhexane mirror enantiomers Et Et Pr Pr Me Me Me H H Me H H Two compounds that are non-superimposable mirror images (the two "hands") are called enantiomers. Introduction To Stereochemistry Structural (constitutional) Isomers - Compounds of the same molecular formula with different connectivity (structure, constitution) 2-methylpentane 3-methylpentane Conformational Isomers - Compounds of the same structure that differ in rotation around one or more single bonds Me Me H H H Me H H H H Me H Configurational Isomers or Stereoisomers - Compounds of the same structure that differ in one or more aspects of stereochemistry (how groups are oriented in space - enantiomers or diastereomers) We need a a way to describe the stereochemistry! Me H H Me 3-methylhexane 3-methylhexane The CIP System Revisited 1.
    [Show full text]
  • Chirality and Enantiomers
    16.11.2010 Bioanalytics Part 5 12.11.2010 Chirality and Enantiomers • Definition: Optical activity • Properties of enantiomers • Methods: – Polarimetry – Circular dichroism • Nomenclature • Separation of enantiomers • Determination of enantiomeric excess (ee) Determination of absolute configuration • Enantiomeric ratio (E‐value) 1 16.11.2010 Definitions Enantiomers: the two mirror images of a molecule Chirality: non‐superimposable mirror‐images •Depends on the symmetry of a molecule •Point‐symmetry: asymmetric C, Si, S, P‐atoms •Helical structures (protein α‐helix) Quarz crystals snail‐shell amino acids Properties of Enantiomers – Chemical identical – Identical UV, IR, NMR‐Spectra – Differences: • Absorption and refraction of circular polarized light is different – Polarimetry, CD‐spectroscopy • Interaction with other chiral molecules/surfaces is different – Separation of enantiomers on chiral columns (GC, HPLC) 2 16.11.2010 Chiral compounds show optical activity A polarimeter is a device which measures the angle of rotation by passing polarized light through an „optical active“ (chiral) substance. Interaction of light and matter If light enters matter, its intensity (amplitude), polarization, velocity, wavelength, etc. may alter. The two basic phenomena of the interaction of light and matter are absorption (or extinction) and a decrease in velocity. 3 16.11.2010 Interaction of light and matter Absorption means that the intensity (amplitude) of light decreases in matter because matter absorbs a part of the light. (Intensity is the square of amplitude.) Interaction of light and matter The decrease in velocity (i.e. the slowdown) of light in matter is caused by the fact that all materials (even materials that do not absorb light at all) have a refraction index, which means that the velocity of light is smaller in them than in vacuum.
    [Show full text]
  • Chapter 8. Chiral Catalysts José M
    Chapter 8. Chiral Catalysts José M. Fraile, José I. García, José A. Mayoral 1. The Origin of Enantioselectivity in Catalytic Processes: the Nanoscale of Enantioselective Catalysis. Enantiomerically pure compounds are extremely important in fields such as medicine and pharmacy, nutrition, or materials with optical properties. Among the different methods to obtain enantiomerically pure compounds, asymmetric catalysis1 is probably the most interesting and challenging, in fact one single molecule of chiral catalyst can transfer its chiral information to thousands or even millions of new chiral molecules. Enantioselective reactions are the result of the competition between different possible diastereomeric reaction pathways, through diastereomeric transition states, when the prochiral substrate complexed to the chiral catalyst reacts with the corresponding reagent. The efficiency of the chirality transfer, measured as enantiomeric excess [% ee = (R−S)/(R+S) × 100], depends on electronic and steric factors in a very subtle form. A simple calculation shows that differences in energy of only 2 kcal/mol between these transition states are enough to obtain more than 90% ee, and small changes in any of the participants in the catalytic process can modify significantly this difference in energy. Those modifications may occur in the near environment of the catalytic centre, at less than 1 nm scale, but also at longer distances in the catalyst, substrate, reagent, solvent, or support in the case of immobilized catalysts. This is the reason because asymmetric
    [Show full text]
  • Chirality in Supramolecular Assemblies: Causes and Consequences F
    To purchase this product, please visit https://www.wiley.com/en-us/9781118867334 Chirality in Supramolecular Assemblies: Causes and Consequences F. Richard Keene (Editor) E-Book 978-1-118-86731-0 January 2017 $146.00 Hardcover 978-1-118-86734-1 November 2016 $182.00 O-Book 978-1-118-86733-4 December 2016 Available on Wiley Online Library DESCRIPTION Supramolecular chemistry deals with the organisation of molecules into defined assemblies using non-covalent interactions, including weaker and reversible interactions such as hydrogen bonds, and metal-ligand interactions. The aspect of stereochemistry within such chemical architectures, and in particular chirality, is of special interest as it impacts on considerations of molecular recognition, the development of functional materials, the vexed question of homochirality, nanoscale effects of interactions at interfaces, biocatalysis and enzymatic catalysis, and applications in organic synthesis. Chirality in Supramolecular Assemblies addresses many of these aspects, presenting a broad overview of this important and rapidly developing interdisciplinary field. Topics covered include: • Origins of molecular and topological chirality • Homochirogenesis • Chirality in crystallinity • Host-guest behavior • Chiral influences in functional materials • Chirality in network solids and coordination solids • Aspects of chirality at interfaces • Chirality in organic assemblies • Chirality related to biocatalysis and enzymes in organic synthesis. This book is a valuable reference for researchers in the molecular sciences, materials science and biological science working with chiral supramolecular systems. It provides summaries and special insights by acknowledged international experts in the various fields. ABOUT THE AUTHOR Emeritus Professor F. Richard Keene Adjunct Professor of Chemistry, School of Pharmacy & Molecular Sciences, James Cook University, Australia and Department of Chemistry, University of Canterbury, New Zealand.
    [Show full text]
  • Amino Acid Catalyzed Direct Asymmetric Mannich Type Reactions Employing Unmodified Donors: Structure Based Catalyst Screening for Anti/Syn Selectivity
    Asian Journal of Chemistry Vol. 20, No. 7 (2008), 5203-5208 Amino Acid Catalyzed Direct Asymmetric Mannich Type Reactions Employing Unmodified Donors: Structure Based Catalyst Screening for Anti/syn Selectivity SUBHENDU DAS and RAJESH K. SINGH* Department of Chemistry, North Orissa University, Takatpur, Baripada-757 003, India E-mail: [email protected] Amino acid catalyzed direct Mannich-type additions to N-Tos protected α-imino ethyl glyoxylate employing unmodi- fied carbonyl donors is described. The reaction was performed in DMSO using a catalytic amount (30 mol %) of L-proline and its derivatives providing a facile route to functionalized β-keto substituted α-amino acid derivatives with excellent diastereo- and enantioselectivities. Unmodified 3-pentanone and cyclohexanone were used as donors for the one pot gener- ation of two quaternary stereocenter. Organocatalysis using L-proline and 5,5-dimethyl thiazolidinium-4-carboxylate were typically syn-diastereoselective. Anti-diastereoselectivity was achieved using (S)-2-methoxymethyl-pyrrolidine and L-proline benzyl ester. Stereochemical outcomes are explained on the basis of previously proposed transition state and the reasons governing syn- and anti-selectivity are described. Poor selectivity of (S)-2-methoxy-methylpyrrolidine compared to L-proline benzyl ester in contrast to earlier reports are expla- ined in terms of a fast cis-trans event and possible sterics. Key Words: Amino acids, Mannich reaction, Anti/syn Selectivity. INTRODUCTION Stereoselective transformation employing asymmetric organocatalysis is a rapidly growing field1-3. Reactions utilizing proline as chiral enantio- selective organocatalyst in catalytic amount has been the focus of great interest recently4,5. Organocatalytic reactions of proline and its derivatives has been well demonstrated for its versatility and potential to create both functional and structural diversity6.
    [Show full text]
  • A Review on Chiral Chromatography and Its Application to the Pharmaceutical Industry
    Chemsearch Journal 2(1): 8 - 11 Publication of Chemical Society of Nigeria, Kano Chapter CHIRAL CHROMATOGRAPHY AND ITS APPLICATION TO THE PHARMACEUTICAL INDUSTRY: A REVIEW Mudi, S. Y. and *Muhammad, A. Department of Pure and Industrial Chemistry, Bayero University, PMB 3011, Kano. *Correspondence author: [email protected] ABSTRACT Chiral chromatographic enantioseparation has been in practice by researchers. There has been a considerable interest in the synthesis and separation of enantiomers of organic compounds especially because of their importance in the biochemical and pharmaceutical industries. Often, these compounds are purified rather than being produced by chiral-specific synthesis. We herein present a general discussion that focuses on the chromatographic enantioseparation, which we hope will be useful to chromatographic and pharmaceutical industries. Keywords: Chiral chromatography, enantioseparation, pharmaceutical industry. INTRODUCTION giving differing affinities between the analytes Chromatography is the collective term for a set of (Schreier et al., 1995). laboratory techniques for the separation of mixtures. It The main goal of this review is to provide a brief involves passing a mixture dissolved in a "mobile overview of chiral separations to researchers who phase" through a “stationary phase”, which separates are versed in the area of analytical separations but the analyte from other compounds in the mixture unfamiliar with chiral separations. This review based on differential partitioning between the mobile highlights significant issues of the chiral and stationary phases. Subtle differences in a separations and provides salient examples from compound's partition coefficient result in differential specific classes of chiral selectors where retention on the stationary phase and thus effecting appropriate. the separation (Laurence and Christopher, 1989; Pascal et al., 2000).
    [Show full text]
  • A Tool for Chirality Control in Asymmetric Catalysis
    Flexibility – A Tool for Chirality Control in Asymmetric Catalysis Raivis Žalubovskis Doctoral Thesis Stockholm 2006 Akademisk avhandling som med tillstånd av Kungl Tekniska Högskolan i Stockholm framlägges till offentlig granskning för avläggande av filosofie doktorsexamen i kemi med inrikting mot organisk kemi, måndagen den 27 november, kl 10.00 i sal F3, KTH, Lindstedtsvägen 26, Stockholm. Avhandlingen försvaras på engelska. Opponent är Professor Alexandre Alexakis, Université de Genève, Schweiz. ISBN 91-7178-491-8 ISRN KTH/IOK/FR--06/104--SE ISSN 1100-7974 TRITA-IOK Forskningsrapport 2006:104 © Raivis Zalubovskis Universitetsservice US AB, Stockholm Zalubovskis, R. 2006 ”Flexibility – A Tool for Chirality Control in Asymmetric Catalysis”, Organic Chemistry, KTH Chemical Science and Engineering, SE-100 44 Stockholm, Sweden. Abstract This thesis deals with the design and synthesis of ligands for asymmetric catalysis: palladium catalyzed allylic alkylations, and rho- dium and iridium catalyzed hydrogenations of olefins. Chirally flexible phosphepine ligands based on biphenyl were synthesized and their properties were studied. The rotation barrier for configurationally flexible phosphepines was determined by NMR spectroscopy. The ratio of the atropisomers was shown to depend on the group bound to phosphorus. Only complexes with two homochiral ligands bound to the metal center were observed upon complexation with Rh(I). It was shown that one diastereomer of the flexible ligand exhibits higher activity but lower selectivity than its diastereomer in the rhodium catalyzed hydrogenation of methyl α-acetamido- cinnamate. These ligands were also tested in nickel catalyzed silabora- tions. Chiral P,N-ligands with pseudo-C2 and pseudo-CS symmetry based on pyrrolidines-phospholanes or azepines-phosphepines were synthesized and studied in palladium catalyzed allylic alkylations.
    [Show full text]
  • The Development of Biocatalysis As a Tool for Drug Discovery
    368 CHIMIA 2020, 74, No. 5 BUILDING BRIDGES BETWEEN BIOTECHNOLOGY AND CHEMISTRY – IN MEMORIAM ORESTE GHISALBA doi:10.2533/chimia.2020.368 Chimia 74 (2020) 368–377 © J. Schwarz, K. Rosenthal, R. Snajdrova, M. Kittelmann, and S. Lütz The Development of Biocatalysis as a Tool for Drug Discovery Jenny Schwarz§a, Katrin Rosenthal§a, Radka Snajdrovab, Matthias Kittelmannc, and Stephan Lütz*a In memoriam Prof. Dr. O. Ghisalba (1946–2018) Abstract: Enzymes are versatile biocatalysts capable of performing selective reactions. The advantages of en- zymes in comparison to classical chemistry including chemical catalysts are the generally milder process condi- tions and avoidance of harmful reactants. Their high selectivity and specificity are especially beneficial for the enzymatic synthesis of new products with potential applications in drug research. Therefore, in the past decades, the utilization of isolated enzymes or whole-cell biocatalysts has spread through a growing number of biotech- nological industries. The applications comprise the production of chiral building blocks for the pharmaceutical and fine chemical industry, the enzymatic synthesis of drug metabolites for testing of toxicity, function, biological activity, degradation and the production of biocatalytically modified natural products, which all play a role in drug discovery. Especially Oreste Ghisalba’s contributions, which paved the way for the industrial use of enzymes, will be considered in this review. Keywords: Biocatalysis · Chiral building blocks · Drug metabolites · Natural product modifications · Pharmacological activity Stephan Lütz holds the chair for Bioprocess Matthias Kittelmann studied microbiol- Engineering at TU Dortmund University ogy/biochemistry in Bonn (Germany) and since 2016. He studied chemistry in Bonn, received his diploma in 1984 on the micro- where he also completed his PhD studies in biota of industrial vinegar fermentations.
    [Show full text]
  • Recent Advances in Biocatalyst Development in the Pharmaceutical Industry
    Pharmaceutical Review Pharm. Bioprocess. (2013) 1(2), 179–196 Recent advances in biocatalyst development in the pharmaceutical industry Biocatalysts are increasingly employed as more efficient and environmentally safer Mingzi M Zhang†1, Xiaoyun alternatives to traditional chemical catalysts in the manufacturing of fine chemicals. Su†1, Ee Lui Ang1 & This is driven by advances in recombinant DNA technology, protein engineering and Huimin Zhao*1,2 bioinformatics, all of which are critical in the discovery, tailoring and optimization of 1Metabolic Engineering Research enzymes for industrial processes. In this article we review these key technological in- Laboratory, Institute of Chemical & Engineering Sciences, Agency for novations, as well as highlight the strategic application of these tools in the develop- Science, Technology & Research, ment of biocatalysts in the production of advanced pharmaceutical intermediates. Singapore 2Departments of Chemical & Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA The synthesis of pharmaceutical products covery and development for pharmaceutical *Author for correspondence: and therapeutic agents using biological sys- processes. For a comprehensive summary of Tel. : +1 217 333 2631 tems is becoming increasingly important for recent examples of biocatalyst application E-mail: zhao5@illinois. edu the healthcare industry. Integral to pharma- in the pharmaceutical industry, readers can †Authors contributed equally ceutical bioprocessing is the development refer
    [Show full text]