Functional Derivatives of Carboxylic Acids
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De Novo Biosynthesis of Terminal Alkyne-Labeled Natural Products
De novo biosynthesis of terminal alkyne-labeled natural products Xuejun Zhu1,2, Joyce Liu2,3, Wenjun Zhang1,2,4* 1Department of Chemical and Biomolecular Engineering, 2Energy Biosciences Institute, 3Department of Bioengineering, University of California, Berkeley, CA 94720, USA. 4Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. *e-mail:[email protected] 1 Abstract: The terminal alkyne is a functionality widely used in organic synthesis, pharmaceutical science, material science, and bioorthogonal chemistry. This functionality is also found in acetylenic natural products, but the underlying biosynthetic pathways for its formation are not well understood. Here we report the characterization of the first carrier protein- dependent terminal alkyne biosynthetic machinery in microbes. We further demonstrate that this enzymatic machinery can be exploited for the in situ generation and incorporation of terminal alkynes into two natural product scaffolds in E. coli. These results highlight the prospect for tagging major classes of natural products, including polyketides and polyketide/non-ribosomal peptide hybrids, using biosynthetic pathway engineering. 2 Natural products are important small molecules widely used as drugs, pesticides, herbicides, and biological probes. Tagging natural products with a unique chemical handle enables the visualization, enrichment, quantification, and mode of action study of natural products through bioorthogonal chemistry1-4. One prevalent bioorthogonal reaction is -
Phospholipid:Diacylglycerol Acyltransferase: an Enzyme That Catalyzes the Acyl-Coa-Independent Formation of Triacylglycerol in Yeast and Plants
Phospholipid:diacylglycerol acyltransferase: An enzyme that catalyzes the acyl-CoA-independent formation of triacylglycerol in yeast and plants Anders Dahlqvist*†‡, Ulf Ståhl†§, Marit Lenman*, Antoni Banas*, Michael Lee*, Line Sandager¶, Hans Ronne§, and Sten Stymne¶ *Scandinavian Biotechnology Research (ScanBi) AB, Herman Ehles Va¨g 2 S-26831 Svaloˆv, Sweden; ¶Department of Plant Breeding Research, Swedish University of Agricultural Sciences, Herman Ehles va¨g 2–4, S-268 31 Svalo¨v, Sweden; and §Department of Plant Biology, Uppsala Genetic Center, Swedish University of Agricultural Sciences, Box 7080, S-750 07 Uppsala, Sweden Edited by Christopher R. Somerville, Carnegie Institution of Washington, Stanford, CA, and approved March 31, 2000 (received for review February 15, 2000) Triacylglycerol (TAG) is known to be synthesized in a reaction that acid) and epoxidated fatty acid (vernolic acid) in TAG in castor uses acyl-CoA as acyl donor and diacylglycerol (DAG) as acceptor, bean (Ricinus communis) and the hawk’s-beard Crepis palaestina, and which is catalyzed by the enzyme acyl-CoA:diacylglycerol respectively. Furthermore, a similar enzyme is shown to be acyltransferase. We have found that some plants and yeast also present in the yeast Saccharomyces cerevisiae, and the gene have an acyl-CoA-independent mechanism for TAG synthesis, encoding this enzyme, YNR008w, is identified. which uses phospholipids as acyl donors and DAG as acceptor. This reaction is catalyzed by an enzyme that we call phospholipid:dia- Materials and Methods cylglycerol acyltransferase, or PDAT. PDAT was characterized in Yeast Strains and Plasmids. The wild-type yeast strains used were microsomal preparations from three different oil seeds: sunflower, either FY1679 (MAT␣ his3-⌬200 leu2-⌬1 trp1-⌬6 ura3-52) (9) or castor bean, and Crepis palaestina. -
Ebook for A2.2 Chemistry
eBook for A2.2 Chemistry Chemistry in Medicine 5.11. [Pages 94 – 107 of A2.2 eBook] • You will be expected to be able to explain the use of indigestion remedies to cure excess hydrochloric acid in the stomach stating the types of compounds used and writing equations for their reactions. • You will be expected to be able to use a back titration to determine the percentage of an active ingredient in an indigestion remedy and perform various calculations on the titration. • You will be expected to be able to explain how to deal with variations in the pH values of skin, explain the role of fatty acids in skin pH and explain the use of corrosive chemicals in removing warts. • You will be expected to be able to recall and explain the use of silver nitrate in the treatment of eye diseases. • You will be expected to be able to explain the action of anticancer drugs, for example cisplatin in preventing DNA replication in cancer cells and how varying the structure of cisplatin affects the efficiency of anticancer activity • You will be expected to be able to carry out titrations to determine the concentration of aspirin in solution and carry out associated calculations. • You will be expected to be able to recall the synthesis of aspirin from salicylic acid and ethanoic anhydride and compare it with the use of ethanoic acid and ethanoyl chloride and explain why the sodium salt of aspirin is often used rather than aspirin. • You will be expected to be able to explain the use of GLC linked to MS to identify drugs and to determine their purity. -
Organic Chemistry
Wisebridge Learning Systems Organic Chemistry Reaction Mechanisms Pocket-Book WLS www.wisebridgelearning.com © 2006 J S Wetzel LEARNING STRATEGIES CONTENTS ● The key to building intuition is to develop the habit ALKANES of asking how each particular mechanism reflects Thermal Cracking - Pyrolysis . 1 general principles. Look for the concepts behind Combustion . 1 the chemistry to make organic chemistry more co- Free Radical Halogenation. 2 herent and rewarding. ALKENES Electrophilic Addition of HX to Alkenes . 3 ● Acid Catalyzed Hydration of Alkenes . 4 Exothermic reactions tend to follow pathways Electrophilic Addition of Halogens to Alkenes . 5 where like charges can separate or where un- Halohydrin Formation . 6 like charges can come together. When reading Free Radical Addition of HX to Alkenes . 7 organic chemistry mechanisms, keep the elec- Catalytic Hydrogenation of Alkenes. 8 tronegativities of the elements and their valence Oxidation of Alkenes to Vicinal Diols. 9 electron configurations always in your mind. Try Oxidative Cleavage of Alkenes . 10 to nterpret electron movement in terms of energy Ozonolysis of Alkenes . 10 Allylic Halogenation . 11 to make the reactions easier to understand and Oxymercuration-Demercuration . 13 remember. Hydroboration of Alkenes . 14 ALKYNES ● For MCAT preparation, pay special attention to Electrophilic Addition of HX to Alkynes . 15 Hydration of Alkynes. 15 reactions where the product hinges on regio- Free Radical Addition of HX to Alkynes . 16 and stereo-selectivity and reactions involving Electrophilic Halogenation of Alkynes. 16 resonant intermediates, which are special favor- Hydroboration of Alkynes . 17 ites of the test-writers. Catalytic Hydrogenation of Alkynes. 17 Reduction of Alkynes with Alkali Metal/Ammonia . 18 Formation and Use of Acetylide Anion Nucleophiles . -
Reaction Kinetics of the Alcoholysis of Substituted Benzoyl Chlorides
Proceedings of the Iowa Academy of Science Volume 61 Annual Issue Article 26 1954 Reaction Kinetics of the Alcoholysis of Substituted Benzoyl Chlorides B. R. Bluestein Coe College Albert Hybl Coe College Yoshimi Al Nishioka Coe College Let us know how access to this document benefits ouy Copyright ©1954 Iowa Academy of Science, Inc. Follow this and additional works at: https://scholarworks.uni.edu/pias Recommended Citation Bluestein, B. R.; Hybl, Albert; and Nishioka, Yoshimi Al (1954) "Reaction Kinetics of the Alcoholysis of Substituted Benzoyl Chlorides," Proceedings of the Iowa Academy of Science, 61(1), 225-232. Available at: https://scholarworks.uni.edu/pias/vol61/iss1/26 This Research is brought to you for free and open access by the Iowa Academy of Science at UNI ScholarWorks. It has been accepted for inclusion in Proceedings of the Iowa Academy of Science by an authorized editor of UNI ScholarWorks. For more information, please contact [email protected]. Bluestein et al.: Reaction Kinetics of the Alcoholysis of Substituted Benzoyl Chlor Reaction Kinetics of the Alcoholysis of Substituted Benzoyl Chlorides By B. R. BLUESTEIN, ALBERT HYBL* AND YosHIMI AL NISHIOKA INTRODUCTION The reaction kinetics of the alcoholysis of substituted benzoyl chlorides was studied. The mechanism of the alcoholysis reaction, which is most generally accepted ( 1), shows that the overall re action should be second-order and that the reaction should be first-order with respect to the acid chloride and first-order with respect to the alcohol. This rate study was carried out using a large excess of alcohol as the solvent, thus obtaining pseudo-first order rate constants, first-order with respect to the acid chloride only. -
Esters Introduction Structurally, an Ester Is a Compound That Has an Alkoxy (OR) Group Attached to the Carbonyl Group
Esters Introduction Structurally, an ester is a compound that has an alkoxy (OR) group attached to the carbonyl group. O R C O R' R may be H, alkyl or aryl, while R’ may be alkyl or aryl only. Esters are widespread in nature. Many of the fragrances of flowers and fruits are due to the esters present. Ethyl butanoate is the chief component that accounts for the pineapple-like aroma and flavour of pineapples. 1:18 PM 1 Nomenclature of Esters Names of esters consist of two words that reflect the composite structure of the ester. The first word is derived from the alkyl group of the alcohol component, and the second word from the carboxylate group of the carboxylic acid component of the ester. The name of the carboxylate portion is derived by substituting the -ic acid suffix of the parent carboxylic acid with the –ate suffix. The alkyl group is cited first followed by the carboxylate group separated by a space. An ester is thus named as an alkyl 1:18 PM alkanoate. 2 IUPAC Nomenclature of Esters Examples 1:18 PM 3 Synthesis of Esters Preparative Strategies Highlighted below are some of the most common strategies by which esters are prepared. The esters are commonly prepared from the reaction of carboxylic acids, acid chlorides and acid anhydrides with alcohols. 1:18 PM 4 Synthesis of Esters Acid-Catalysed Esterification of a Carboxylic Acid and an Alcohol The acid-catalysed reaction of carboxylic acids and alcohols provides esters. Typically, a catalytic amount of a strong inorganic (mineral) acid such as H2SO4, HCl and H3PO4 is used. -
Derivatives of Carboxylic Acid
Derivatives of Carboxylic Acid acid chloride carboxylate nitrile amide acid anhydride ester Nomenclature of Acid Halides IUPAC: alkanoic acid → alkanoyl halide Common: alkanic acid → alkanyl halide I: 3-aminopropanoyl chloride I: 4-nitropentanoyl chloride c: b-aminopropionyl chloride c: g-nitrovaleryl chloride I: hexanedioyl chloride c: adipoyl chloride Rings: (IUPAC only): ringcarbonyl halide I: benzenecarbonyl bromide I: 3-cylcopentenecarbonyl chloride c: benzoyl bromide Nomenclature of Acid Anhydrides Acid anhydrides are prepared by dehydrating carboxylic acids acetic anhydride ethanoic acid ethanoic anhydride I: benzenecarboxylic anhydride I: butanedioic acid I: butanedioic anhydride c: benzoic andhydride c: succinic acid c: succinic anhydride Some unsymmetrical anhydrides I: ethanoic methanoic I: benzoic methanoic anhydride anhydride I: cis-butenedioic c: benzoic formic anhydride anhydride c: acetic formic anhydride Nomenclature of Esters Esters occur when carboxylic acids react with alcohols I: phenyl methanoate I: t-butyl benzenecarboxylate I: methyl ethanoate c: phenyl formate c: methyl acetate c: t-butyl benzoate I: isobutyl I: cyclobutyl 2- I: dimethyl ethanedioate cyclobutanecarboxylate methylpropanoate c: cyclobutyl a- c: dimethyl oxalate c: none methylpropionate Cyclic Esters Reaction of -OH and -COOH on same molecule produces a cyclic ester, lactone. To name, add word lactone to the IUPAC acid name or replace the -ic acid of common name with -olactone. 4-hydroxy-2-methylpentanoic acid lactone -methyl- -valerolactone Amides Product of the reaction of a carboxylic acid and ammonia or an amine. Not basic because the lone pair on nitrogen is delocalized by resonance. Classes of Amides 1 amide has one C-N bond (two N-H). 2 amide or N-substituted amide has two C-N bonds (one N-H). -
Fermentation and Ester Taints
Fermentation and Ester Taints Anita Oberholster Introduction: Aroma Compounds • Grape‐derived –provide varietal distinction • Yeast and fermentation‐derived – Esters – Higher alcohols – Carbonyls – Volatile acids – Volatile phenols – Sulfur compounds What is and Esters? • Volatile molecule • Characteristic fruity and floral aromas • Esters are formed when an alcohol and acid react with each other • Few esters formed in grapes • Esters in wine ‐ two origins: – Enzymatic esterification during fermentation – Chemical esterification during long‐term storage Ester Formation • Esters can by formed enzymatically by both the plant and microbes • Microbes – Yeast (Non‐Saccharomyces and Saccharomyces yeast) – Lactic acid bacteria – Acetic acid bacteria • But mainly produced by yeast (through lipid and acetyl‐CoA metabolism) Ester Formation Alcohol function Keto acid‐Coenzyme A Ester Ester Classes • Two main groups – Ethyl esters – Acetate esters • Ethyl esters = EtOH + acid • Acetate esters = acetate (derivative of acetic acid) + EtOH or complex alcohol from amino acid metabolism Ester Classes • Acetate esters – Ethyl acetate (solvent‐like aroma) – Isoamyl acetate (banana aroma) – Isobutyl acetate (fruit aroma) – Phenyl ethyl acetate (roses, honey) • Ethyl esters – Ethyl hexanoate (aniseed, apple‐like) – Ethyl octanoate (sour apple aroma) Acetate Ester Formation • 2 Main factors influence acetate ester formation – Concentration of two substrates acetyl‐CoA and fusel alcohol – Activity of enzyme responsible for formation and break down reactions • Enzyme activity influenced by fermentation variables – Yeast – Composition of fermentation medium – Fermentation conditions Acetate/Ethyl Ester Formation – Fermentation composition and conditions • Total sugar content and optimal N2 amount pos. influence • Amount of unsaturated fatty acids and O2 neg. influence • Ethyl ester formation – 1 Main factor • Conc. of precursors – Enzyme activity smaller role • Higher fermentation temp formation • C and N increase small effect Saerens et al. -
Amide, and Paratoluenesulfonamide on the Amide of Silver,On the Imides
68 CHEMISTRY: E. C. FRANKLIN METALLIC SALTS OF AMMONO ACIDS By Edward C. Franklin DEPARTMENT OF CHEMISTRY, STANFORD UNIVERSITY Presented to the Academy, January 9. 1915 The Action of Liquid-Ammonia Solutions of Ammono Acids on Metallic Amides, Imides, and Nitrides. The acid amides and imides, and the metallic derivatives of the acid amides and imides are the acds, bases, and salts respectively of an ammonia system of acids, bases, and salts.1 Guided by the relationships implied in the above statement Franklin and Stafford were able to prepare potassium derivatives of a considerable number of acid amides by the action of potassium amide on certain acid amides in solution in liquid ammonia. That is to say, an ammono base, potassium amide, was found to react with ammono acids in liquid ammonia to form ammono salts just as the aquo base, potassium hydrox- ide, acts upon aquo acids in water solution to form aquo salts. Choos- ing, for example, benzamide and benzoic acid as representative acids of the two systems, the analogous reactions taking place respectively in liquid ammonia and water are represented by the equations: CH6CONH2+KNH2 = C6H5CONHK + NHs. CseHCONH2 + 2KNH2 = CIHsCONK2 + 2NH3. CH6tCOOH + KOH = CIH6COOK + H2O. The ammono acid, since it is dibasic, reacts with either one or two molecules of potassium amide to form an acid and a neutral salt. Having thus demonstrated the possibility of preparing ammono salts of potassium by the interaction of potassium amide and acid amides in liquid ammonia solution, it was further found that ammono salts of the heavy metals may be prepared by the action of liquid ammonia solutions of ammono acids on insoluble metallic amides, imides, and nitrides-that is, by reactions which are analogous to the formation of aquo salts in water by the action of potassium hydroxide on insoluble metallic hydroxides and oxides. -
Amide Activation: an Emerging Tool for Chemoselective Synthesis
Featuring work from the research group of Professor As featured in: Nuno Maulide, University of Vienna, Vienna, Austria Amide activation: an emerging tool for chemoselective synthesis Let them stand out of the crowd – Amide activation enables the chemoselective modification of a large variety of molecules while leaving many other functional groups untouched, making it attractive for the synthesis of sophisticated targets. This issue features a review on this emerging field and its application in total synthesis. See Nuno Maulide et al., Chem. Soc. Rev., 2018, 47, 7899. rsc.li/chem-soc-rev Registered charity number: 207890 Chem Soc Rev View Article Online REVIEW ARTICLE View Journal | View Issue Amide activation: an emerging tool for chemoselective synthesis Cite this: Chem. Soc. Rev., 2018, 47,7899 Daniel Kaiser, Adriano Bauer, Miran Lemmerer and Nuno Maulide * It is textbook knowledge that carboxamides benefit from increased stabilisation of the electrophilic carbonyl carbon when compared to other carbonyl and carboxyl derivatives. This results in a considerably reduced reactivity towards nucleophiles. Accordingly, a perception has been developed of amides as significantly less useful functional handles than their ester and acid chloride counterparts. Received 27th April 2018 However, a significant body of research on the selective activation of amides to achieve powerful DOI: 10.1039/c8cs00335a transformations under mild conditions has emerged over the past decades. This review article aims at placing electrophilic amide activation in both a historical context and in that of natural product rsc.li/chem-soc-rev synthesis, highlighting the synthetic applications and the potential of this approach. Creative Commons Attribution 3.0 Unported Licence. -
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United States Patent [191 [11] Patent Number: 5,070,175 Tsumura Et Al
United States Patent [191 [11] Patent Number: 5,070,175 Tsumura et al. [45] Date of Patent: Dec. 3, 1991 [54] METHOD FOR THE PREPARATION OF AN Primary Examiner-Morton Foelak ORGANOPOLYSILOXANE CONTAINING Attorney, Agent, or Firm-Millen, White & Zelano TETRAFUNCI'IONAL SILOXANE UNITS [57] ABSTRACT [75] Inventors: Hiroshi Tsumura; Kiyoyuki Mutoh, An ef?cient and economically advantageous method is both of Gunma; Kazushi Satoh, proposed for the preparation of an organopolysiloxane Tokyo; Ken-ichi Isobe, Gunma, all of comprising tetrafunctional siloxane units, i.e. Q units, Japan and, typically, monofunctional siloxy units, i.e. M units, [73] Assignee: Shin-Etsu Chemical Co., Ltd., Tokyo, and useful as a reinforcing agent in silicone rubbers. The Japan method comprises the steps of: mixing the reactants for providing the Q and M units, such as ethyl orthosilicate [21] Appl. No.;. 706,148 and trimethyl methoxy silane, in a desired molar ratio; [22] Filed: May 28, 1991 and heating the mixture at a temperature higher by at least 10° C. than the boiling point of the mixture under [30] Foreign Application Priority Data normal pressure in a closed vessel in the presence of May 29, 1990 [JP] Japan ............ .Q .................. .. 2-l39ll9 water and a catalyst such as a sulfonic acid group-con taining compound. In addition to the greatly shortened [51] Int. 01.5 ............................................ .. C08G 77/06 reaction time and remarkably decreased contents of [52] U.S. c1. ...................................... .. 528/12; 528/10; residual alkoxy groups and gelled matter in the product, 528/21; 528/23; 528/34; 528/36 the method is advantageous also in respect of the ab [58] Field of Search .................... -
APPENDIX G Acid Dissociation Constants
harxxxxx_App-G.qxd 3/8/10 1:34 PM Page AP11 APPENDIX G Acid Dissociation Constants § ϭ 0.1 M 0 ؍ (Ionic strength ( † ‡ † Name Structure* pKa Ka pKa ϫ Ϫ5 Acetic acid CH3CO2H 4.756 1.75 10 4.56 (ethanoic acid) N ϩ H3 ϫ Ϫ3 Alanine CHCH3 2.344 (CO2H) 4.53 10 2.33 ϫ Ϫ10 9.868 (NH3) 1.36 10 9.71 CO2H ϩ Ϫ5 Aminobenzene NH3 4.601 2.51 ϫ 10 4.64 (aniline) ϪO SNϩ Ϫ4 4-Aminobenzenesulfonic acid 3 H3 3.232 5.86 ϫ 10 3.01 (sulfanilic acid) ϩ NH3 ϫ Ϫ3 2-Aminobenzoic acid 2.08 (CO2H) 8.3 10 2.01 ϫ Ϫ5 (anthranilic acid) 4.96 (NH3) 1.10 10 4.78 CO2H ϩ 2-Aminoethanethiol HSCH2CH2NH3 —— 8.21 (SH) (2-mercaptoethylamine) —— 10.73 (NH3) ϩ ϫ Ϫ10 2-Aminoethanol HOCH2CH2NH3 9.498 3.18 10 9.52 (ethanolamine) O H ϫ Ϫ5 4.70 (NH3) (20°) 2.0 10 4.74 2-Aminophenol Ϫ 9.97 (OH) (20°) 1.05 ϫ 10 10 9.87 ϩ NH3 ϩ ϫ Ϫ10 Ammonia NH4 9.245 5.69 10 9.26 N ϩ H3 N ϩ H2 ϫ Ϫ2 1.823 (CO2H) 1.50 10 2.03 CHCH CH CH NHC ϫ Ϫ9 Arginine 2 2 2 8.991 (NH3) 1.02 10 9.00 NH —— (NH2) —— (12.1) CO2H 2 O Ϫ 2.24 5.8 ϫ 10 3 2.15 Ϫ Arsenic acid HO As OH 6.96 1.10 ϫ 10 7 6.65 Ϫ (hydrogen arsenate) (11.50) 3.2 ϫ 10 12 (11.18) OH ϫ Ϫ10 Arsenious acid As(OH)3 9.29 5.1 10 9.14 (hydrogen arsenite) N ϩ O H3 Asparagine CHCH2CNH2 —— —— 2.16 (CO2H) —— —— 8.73 (NH3) CO2H *Each acid is written in its protonated form.