DOCSLIB.ORG

Converting Chemical Names to Structures with Name=Struct

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Converting Chemical Names to Structures with Name=Struct Converting Chemical Names to Structures with Name=Struct Abstract With either version, Name=Struct sets the standard for coverage and accuracy in generating structures from chemical names. Name=Struct is CambridgeSoft’s comprehensive algorithm for converting English Table of Contents 1 chemical names into chemical structure diagrams. General Nomenclature Issues . 2 It is designed to be as practical as possible, interpreting chemical names as they are actually Capabilities . 8 used by chemists. In addition to recognizing most IUPAC and CAS Names . 8 of the official rules and recommendations of Supported Procedures. 9 International Union of Pure and Applied Accuracy . 10 Chemistry (IUPAC), the International Union of Speed . 10 Biochemistry and Molecular Biology (IUBMB), Limitations . 10 and the Chemical Abstracts Service (CAS), Platform Limitations . 10 Name=Struct also recognizes the shorthand, slang, Chemistry Limitations . 11 and neologisms of everyday usage. It is extremely Structural Limitations. 11 tolerant of deviations from the “official” rules in Nomenclature Limitations . 12 regard to spaces, parentheses, and punctuation. Nomenclature Classes Handled by Name=Struct Both regular names (“chlorobenzene”) and Chains. 13 inverted names (“benzene, chloro-”) are supported. Rings . 14 In addition, it has an extensive algorithm for the Natural Products. 15 identification of common “typos” (typing errors, Functional Groups Containing Nitrogen . 17 such as “mehtyl”) to increase the odds of Functional Groups Containing Oxygen . 18 generating structures for the names it is given. Acids . 20 Name=Struct is available in two forms: a batch Ions and Radicals . 23 application, and an interactive version that is part Salts . 24 of CS ChemDraw 8.0 Ultra. Isotopes . 25 Stereochemistry . 25 Miscellaneous. 27 1. A description of an earlier version of Name=Struct was published as Brecher, J. “Name=Struct: A Practical Approach to the Sorry State of Real-Life Chemical Nomencla- ture.” J. Chem. Inf. Comput. Sci. 39, 6, 943-950. General In general, Name=Struct is designed to be as smart as a real chemist—if a nomenclature human chemist can understand what structure is intended by a given name, issues then Name=Struct should manage to do so as well. Chemical names come in many styles. Some names truly do conform to published nomenclature recommendations, most commonly from IUPAC, IUBMB, or CAS. Clearly, Name=Struct needs to recognize these names, but that’s only the start of the problem. First, each of those organizations has changed their recommendations over time. There is no way to know which version of the recommendations were used to generate any given name, and so Name=Struct must recognize names produced by all versions. Changes in IUPAC Recommendations NH IUPAC 1979 recommendations S OH (methylthio)cyclohexane 2-(methylamino)-1-phenylethanol NH IUPAC 1993 recommendations S OH (methylsulfanyl)cyclohexane 2-(methylazanyl)-1-phenylethanol Second, many chemical names use trivial forms that have long been forbidden by all of those nomenclature bodies. Nonetheless, these trivial names are used frequently enough that most chemists will recognize their meaning, and so Name=Struct should as well. Trivial and Structural Names OH OH O Structures for trivial names O generated by Name=Struct N N H H paracetamol acetaminophen OH Structural name generated O by Struct=Name N H N-(4-hydroxyphenyl)acetamide 2 Converting Chemical Names to Structures with Name=Struct Finally, even though those organizations have published nomenclature recommendations, the recommendations are extremely complex and difficult to understand. Even the best-intentioned chemist will often produce names that—technically or egregiously—violate the published norms. As long as the meaning of the name remains clear, Name=Struct should be able to handle it. To achieve this goal, Name=Struct attempts to be as flexible as possible. Capitalization, font type, and font style are completely ignored. Most punctuation is ignored as well, regardless of whether it is used correctly as per the published recommendations or not. Spelling, similarly, is important only for clarity: Name=Struct will interpret many common misspellings correctly, but proper spelling is much more likely to be interpreted correctly. More recently, extensive typo recognition has been added, increasing the likelihood that names will be interpreted correctly even if they are not technically correct. Capitalization Capitalization is completely ignored when interpreting chemical names. “Benzene”, “benzene”, and “BENZENE” clearly all represent the same compound. There are a few nomenclature rules that call for a given capitalization. Possibly the most common of these is the “n” prefix. When used before an alkane, it indicates the straight-chain form (“n-butylamine”). When capitalized, it indicates that a ligand should be attached directly to a nitrogen atom (“N-chloroaniline”). If capitalization is ignored, there is a potential for ambiguity (“n- butylaniline”). In our experience, this is rarely an issue. Not only are names of this type uncommon, but the intended structure is almost always intended to be “the straight chain form on the nitrogen” (“N-(n-butyl)aniline”). It is much more common to find names with completely non-standard capitalization than it is to find ones where the capitalization actually makes a difference. Name=Struct interprets all of the following names identically: N-Butylaniline • n-butylaniline • n-Butylaniline • n-BUTYLANILINE • N-butylaniline • N-Butylaniline NH • N-BUTYLANILINE Converting Chemical Names to Structures with Name=Struct 3 Punctuation For the most part, Name=Struct ignores punctuation. It can be present, absent, or incorrect without affecting the interpretation of a chemical name. There are a few exceptions: Commas must be present in CAS-style inverted names. “Benzene, chloro-” and “chlorobenzene” are interpreted identically. “Benzene chloro” without the comma cannot be interpreted. Parentheses, brackets, and braces should be used for ambiguous names. “(Trichloromethyl)silane” is different from “trichloro(methyl)silane”. They also must be paired and nested appropriately, each open parenthesis with a matching close parenthesis and so on. Otherwise, parentheses, brackets, or braces may used interchangeably. Some punctuation is required to separate digits. Traditionally, this duty is performed by a comma: “1,1-” vs. “11-”, but Name=Struct will recognize any reasonable separator—for example “1-1-”—as acceptable. Other roles are traditionally performed by periods, colons, and hyphens, but Name=Struct will recognize any reasonable separator there as well. Spaces are ignored whenever possible, but there are a few cases where the space performs a vital role. This is most commonly important for esters. The following names represent very different structures: Effect of spaces in related names methyl ethyl malonate methylethyl malonate O O O O O O O OH methyl ethylmalonate methylethylmalonate O OH O O -O O O O- 4 Converting Chemical Names to Structures with Name=Struct Baseline Superscripts are occasionally called for by various published nomenclature recommendations. Name=Struct handles them in a way consistent with its handling of other typographical issues. If the superscript consists of a number and immediately follows some other number, they must be separated in some fashion (parentheses are most often used). Thus “13,7” becomes “1(3,7)” and should not be represented as the confusing “13,7”. In all other cases, the superscripted characters should follow the previous characters with no added separation: “N3,N4,N5-trimethyloctane-3,4,5-triamine”, for example, should be entered as “N3,N4,N5-trimethyloctane-3,4,5-triamine”. N3,N4,N5-trimethyloctane-3,4,5-triamine NH H N HN Fonts Chemical names are not usually defined by the particular font used to display the name. There is one exception to this rule. Some chemical names are supposed to use Greek characters. Unfortunately, not only is this nuance lost on many people, but it is also impossible in many circumstances, such as in a text-only database. Accordingly, Name=Struct will recognize any reasonable representation of Greek characters. The following names are all interpreted identically: α-methylphenethylamine • a-methylphenethylamine • alpha-methylphenethylamine • .alpha.-methylphenethylamine H N • α-methylphenethylamine 2 Italicization All font styles, including italicization, are completely ignored when interpreting chemical names. This will never introduce any ambiguity. Converting Chemical Names to Structures with Name=Struct 5 Spelling Spelling is critically important. There are many pairs of names that differ only by a single character—compare methylamine and menthylamine: Similar spellings NH2 H2N methylamine menthylamine However, in many cases, a human chemist might not even notice an incorrect spelling, and would interpret the name easily. Name=Struct should do the same. Many common misspellings, including “choro”, “cloro”, and “flouro” are automatically recognized (see “Automatic error recognition” below). Elision refers to the elimination of one vowel that is directly followed by another, and is technically required or prohibited in many cases: the rules say to use “propanamine” rather than “propaneamine”. Name=Struct does not enforce those rules; vowels may be elided or not without penalty. Elision H2N H2N propaneamine propanamine Automatic error Because it is designed to interpret real-life usage, Name=Struct also handles
Load more

Recommended publications
  • 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.
    [Show full text]
  • 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).
    [Show full text]
  • Hydrolysis of Acetic Anhydride with Heavy Water (D2O) by a Modified in Situ Reaction Monitoring Technique
    Thermo Fisher Scientific Molecular Spectroscopy 525 Verona Rd, Madison, WI 53711 (608 276-6100 www.thermoscientific.com picoSpin™ 45: Hydrolysis of Acetic Anhydride with Heavy Water (D2O) Dean Antic, Ph.D., Thermo Fisher Scientific, Boulder, CO, USA 1. Introduction In a hydrolysis reaction, a chemical bond is broken by the addition water. Hydrolysis is typically carried out in the presence of a salt of a weak acid or weak base. Water - + autoionizes into hydroxyl ions ( OH) and hydronium ions (H3O ) and acts as a source of a nucleophile and catalyzing acid, but it is also a weak acid and in most cases hydrolysis in water is to slow for the reaction to proceed without the addition of a strong acid. Hydrolysis of anhydrides are, however, often facile in the presence of water where only mild heating of the reaction mixture is necessary. The hydrolysis of acetic anhydride (Ac2O) to acetic acid (AcOH) serves as a model example of the hydrolysis reaction. Acetic anhydride rapidly hydrolyzes in the presence of water, alcohol and catalyzing acid, in this case water. We can monitor the evolution of the reaction using NMR by a modified in situ reaction monitoring whereby a single aliquot of the reaction mixture is injected into the RF coil of the NMR probe. In situ reaction monitoring by NMR has several requirements: 1) reactants and products must be soluble throughout the course of reaction, 2) signals undergoing change must be resolvable and 3) the rate of reaction must slower than the timescale of the NMR experiment. In addition to its applications in the determination of static molecular structures, many NMR experiments are performed to monitor the growth and evolution of resonance signals undergoing dynamic change.
    [Show full text]
  • The Institute of Paper Chemistry
    The Institute of Paper Chemistry Appleton, Wisconsin Doctor's Dissertation Anhydride Derivatives of Trimellitic Anhydride Richard G. Barker June, 1963 ANHYDRIDE DERIVATIVES OF TRIMELLITIC ANHYDRIDE A thesis submitted by Richard G. Barker B.A. 1958, Hamilton College M.S. 1960, Lawrence College in partial fulfillment of the requirements of The Institute of Paper Chemistry for the degree of Doctor of Philosophy from Lawrence College Appleton, Wisconsin June, 1963 TABLE OF CONTENTS Page GENERAL SUMMARY 1 INTRODUCTION 3 Trimellitic Anhydride 3 Unsymmetrical Anhydrides 5 Preparation of Unsymmetrical Anhydrides 6 Disproportionation of Unsymmetrical Anhydrides 8 Hydrolysis of Unsymmetrical Anhydrides 11 Reactions of Unsymmetrical Anhydrides 12 Previous Investigations on the Esterification of Unsymmetrical Anhydrides 12 The Mechanism of Acylation by Unsymmetrical Anhydrides 13 Trifluoroacetic Anhydride as an Esterification Promoter 16 PRESENTATION AND APPROACH TO THE PROBLEM 22 PROCEDURES AND RESULTS 24 The Trimellitic Anhydride-Trifluoroacetic Anhydride Reaction System 24 Preparation of the Unsymmetrical Anhydride of TMA and TFAA 24 Purification and Analysis of the Unsymmetrical Anhydride of TMA and TFAA 25 Disproportionation of the Unsymmetrical Anhydride of TMA and TFAA 27 Hydrolysis of the Unsymmetrical Anhydride of TMA and TFAA 28 Esterification of the Unsymmetrical Anhydride of TMA and TFAA 29 The Unsymmetrical Anhydride of Trimellitic and Acetic Anhydrides 31 Preparation of the Unsymmetrical Anhydride 31 Purification and Analysis of the
    [Show full text]
  • Carboxylic Acid Derivatives Carboxylic Acid Derivatives Are Described As Compounds That Can Be Converted to Carboxylic Acids Via Simple Acidic Or Basic Hydrolysis
    Carboxylic acid Derivatives Carboxylic acid derivatives are described as compounds that can be converted to carboxylic acids via simple acidic or basic hydrolysis. The most important acid derivatives are esters, amides and nitriles, although acid halides and anhydrides are also derivatives (really activated forms of a carboxylic acid). Esters of Carboxylic Acids These are derivatives of carboxylic acids where the hydroxyl group is replaced by an alkoxy group. We have already seen that esters are produced via the reaction of an alcohol with a carboxylic acid. Ch21 Carboxylic acid Derivatives(landscape).docx Page 1 Nomenclature The names of esters are derived from the names of the compounds that are used to create them. The first word of the name comes from the alkyl group of the alcohol, and the second part comes from the carboxylate group of the acid used. E.g. Ch21 Carboxylic acid Derivatives(landscape).docx Page 2 A cyclic ester is called a lactone. IUPAC names of lactones are derived by adding the term lactone at the end of the name of the parent hydroxycarboxylic acid it came from. E.g. Ch21 Carboxylic acid Derivatives(landscape).docx Page 3 Amides of Carboxylic Acids An amide is a composite of a carboxylic acid and an amine (or ammonia). Heating the salt formed when an amine and carboxylic acid react together, drives off the water produced, and an amide is formed. Amides are much less basic than their parent amines since the lone pair of electrons on Nitrogen are delocalized onto the carbonyl oxygen. In fact in strong acid, it is the oxygen that gets protonated first! Ch21 Carboxylic acid Derivatives(landscape).docx Page 4 This conjugation means the N should be sp2 hybridized, and indeed the amide nitrogen has a planar arrangement of bonds with bond angles close to 120°.
    [Show full text]
  • Brønsted-Lowry Acids and Bases the Brønsted-Lowry Definition
    CHAPTER 14 Acids and Bases Acids and bases change the color of compounds called indicators. Hydrangeas Properties of Acids SECTION 1 and Bases OBJECTIVES List five general properties of aqueous acids and bases. Name common binary acids H ow many foods can you think of that are sour? Chances are that and oxyacids, given their almost all the foods you thought of, like those in Figure 1a, owe their chemical formulas. sour taste to an acid. Sour milk contains lactic acid. Vinegar, which can be produced by fermenting juices, contains acetic acid. Phosphoric acid gives a tart flavor to many carbonated beverages. Most fruits contain List five acids commonly used in industry and the laboratory, some kind of acid. Lemons, oranges, grapefruits, and other citrus fruits and give two properties of contain citric acid. Apples contain malic acid, and grape juice contains each. tartaric acid. Many substances known as bases are commonly found in household products, such as those in Figure 1b. Household ammonia is an ammo- Define acid and base accord- nia-water solution that is useful for all types of general cleaning. Sodium ing to Arrhenius’s theory of hydroxide, NaOH, known by the common name lye, is present in some ionization. commercial cleaners. Milk of magnesia is a suspension in water of mag- nesium hydroxide, Mg(OH)2, which is not very water-soluble. It is used Explain the differences as an antacid to relieve discomfort caused by excess hydrochloric acid between strong and weak in the stomach. Aluminum hydroxide, Al(OH)3, and sodium hydrogen acids and bases.
    [Show full text]
  • Chapter 5 Carboxylic Acids and Esters
    Chapter 5 Carboxylic Acids and Esters Chapter 5 Carboxylic Acids and Esters Chapter Objectives: • Learn to recognize the carboxylic acid, ester, and related functional groups. • Learn the IUPAC system for naming carboxylic acids and esters. • Learn the important physical properties of the carboxylic acids and esters. • Learn the major chemical reaction of carboxylic acids and esters, and learn how to predict the products of ester synthesis and hydrolysis reactions. • Learn some of the important properties of condensation polymers, especially the polyesters. Mr. Kevin A. Boudreaux Angelo State University CHEM 2353 Fundamentals of Organic Chemistry Organic and Biochemistry for Today (Seager & Slabaugh) www.angelo.edu/faculty/kboudrea Carboxylic Acids • Carboxylic acids are weak organic acids which contain the carboxyl group (RCO2H): O C O H O RCOOH RCO2H O condensed ways of RCOH writing the carboxyl group a carboxylic acid C H O the carboxyl group • The tart flavor of sour-tasting foods is often caused by the presence of carboxylic acids. 2 Chapter 5 Carboxylic Acids and Esters Nomenclature of Carboxylic Acids 3 Nomenclature of Carboxylic Acids • Select the longest carbon chain containing the carboxyl group. The -e ending of the parent alkane name is replaced by the suffix -oic acid. • The carboxyl carbon is always numbered “1” but the number is not included in the name. • Name the substituents attached to the chain in the usual way. • Aromatic carboxylic acids (i.e., with a CO2H directly connected to a benzene ring) are named after the
    [Show full text]
  • Difference Between Acid Anhydride and Basic Anhydride Key Difference
    Difference Between Acid Anhydride and Basic Anhydride www.differencebetween.com Key Difference - Acid Anhydride vs Basic Anhydride An anhydride is a chemical compound obtained with the elimination of a water compound from a parent compound. There are organic anhydrides and inorganic anhydrides classified based on the presence of C and H atoms. These anhydrides can be either acid anhydrides or basic anhydrides. Most of the oxides formed by the removal of water from an acid are known as an acid anhydride. Basic or base anhydrides are the compounds formed by the removal of water from a base. The key difference between acid anhydrides and base anhydrides is that acid anhydrides are formed from acids whereas basic anhydrides are formed from bases. What is Acid Anhydride? Acid anhydrides are chemical compounds known as oxides that are formed by the removal of water from an acid. An acid is a chemical compound that can donate H+ ions (protons) to a medium. But when an acid is converted to an anhydride, it can no longer release H+ ions. An acid anhydride is essentially composed of two acyl groups bonded to the same oxygen atom (-C(=O)-O-C(=O)). Acidic oxides are often known as acid anhydrides. Figure 01: An Acid anhydride has two acyl groups bonded to one oxygen atom (given in blue). The most common class of acid anhydrides is organic acid anhydrides. These are essentially organic compounds. One of the most important organic acid anhydrides is a carboxylic anhydride. There are inorganic acid anhydrides as well. These are essentially inorganic compounds and do not contain any organic moiety.
    [Show full text]
  • Carboxylic Acids, Esters and Acyl Chlorides
    OCR Chemistry A H432 Carboxylic Acids, Esters and Acyl Chlorides Carboxylic Acids, Esters and Acyl Chlorides O Carboxylic acids contain the –COOH functional group, attached to an alkyl stem. They are widely found in nature, from the methanoic acid in ants, the C ethanoic acid in vinegar to the citric acid in citrus fruits. O H Esters contain the –COO- functional group, with an alkyl group attached to O either side. Esters are widely used in perfumes and flavourings since they C are responsible for the flavours of many foods and the scents of flowers. O O Acyl chlorides contain the –COCl functional group, attached to an alkyl stem. C Cl Acid anhydrides contain the –COOCO- functional group, attached to two alkyl O O groups. They can be considered as two carboxylic acid molecules joined together by a condensation with elimination of a water molecule. C C O Naming carboxylic acids • name the alkyl group, then replace the final 'e' with 'oic acid'. • remember that the carbon in the -COOH group is part of the alkyl chain for naming purposes, so: O O H HCOOH is methanoic acid C CH3COOH is ethanoic acid etc. C6H5COOH is benzoic acid • the -COOH group can only go on the end of a chain, so no numbering is required to identify its position. Like in an aldehyde, the carbon in the –COOH group becomes number 1 in the chain. esters Esters can be considered as derivatives of carboxylic acids, where the hydrogen in the –COOH group has been replaced with an alkyl group. The ester name starts with the name of this alkyl group, then the name from the carboxylic acid, with the ‘-oic acid’ ending replaced with ‘-oate’.
    [Show full text]
  • Ch.21 Carboxylic Acid Derivatives and Nucleophilic Acyl Substitution
    Ch.21 Carboxylic Acid Derivatives and Nucleophilic Acyl Substitution Carboxylic Acid Derivatives O O O O O R C OH R C Cl R C O C R' R C O R' Ester Carboxylic Carboxylic Acid anhydride acid acid chloride O O O O - R C NH2 R C SR' R C O P O R C N - Amide Thioester O Acyl phosphate Nitrile Nucleophilic Acyl Substitution O O Nu- + Y- R Y R Nu 21.1 Nomenclature Acid Halides: RCOX -oic acid → -yl -carboxylic acid → -carbonyl O O Cl Cl Acetyl chloride Benzoyl chloride O Cl Cyclohexanecarbonyl chloride Acid Anhydrides: RCO2COR' acid → anhydride O O O O O O O O O Acetic anhydride Benzoic anhydride Succinic anhydride - anhydride from substituted monocarboxylic acid: bis- - unsymmetrical anhydride: cite two carboxylic groups alphabetically O O O O O Cl Cl O Bis(chloroacetic) anhydride Acetic benzoic anhydride Amides: RCONH2 -(o)ic acid → amide -carboxylic acid → -carboxamide O O O NH2 NH NH2 2 Acetamide Hexanamide Cyclohexanecarboxamide - substututed amide: N-alkyl----amide O O N CH N 3 H N-Methylacetamide N,N-Diethylcyclohexanecarboxamide Esters: RCO2R' - name alkyl group attached to oxygen then -ic acid → -ate O OO O EtO OEt Ethyl acetate Diethyl malonate O O tert-Butyl cyclohexanecarboxylate 21.2 Nucleophilic Acyl Substitution Reactions Nucleophilic acyl substitution: Y = OR', Cl, OCOR', NR'2 OO- Nu- O - R + Y R Y Y R Nu Nu tetrahedral intermediate (alkoxide anion) - addition-elimination mechanism: different from SN2 mechanism Relative Reactivity of Carboxylic Acid Derivatives Steric effect: O O O O R R R H C < < < C R R C H C H R H H H more
    [Show full text]
  • And Oxoacids. Heterofunctional Compounds of Benzene Series - Metabolites and Parent Structures of Medicines
    МІНІСТЕРСТВО ОХОРОНИ ЗДОРОВ’Я УКРАЇНИ ХАРКІВСЬКИЙ НАЦІОНАЛЬНИЙ МЕДИЧНИЙ УНІВЕРСИТЕТ HYDROXY- AND OXOACIDS. HETEROFUNCTIONAL COMPOUNDS OF BENZENE SERIES - METABOLITES AND PARENT STRUCTURES OF MEDICINES Methodical instructions for 1st year students’ self-work in Biological and Bioorganic Chemistry (module 1) ГІДРОКСИ- ТА ОКСОКИСЛОТИ. ГЕТЕРОФУНКЦІОНАЛЬНІ СПОЛУКИ БЕНЗОЛЬНОГО РЯДУ – МЕТАБОЛІТИ ТА РОДОНАЧАЛЬНИКИ ЛІКАРСЬКИХ ЗАСОБІВ Методичні вказівки для самостійної роботи студентів 1-го курсу з біологічної та біоорганічної хімії (модуль 1) Затверджено Вченою радою ХНМУ. Протокол № 10 від 21. 11. 2013 Харків 2014 Hydroxy- and oxoacids. Heterofunctional compounds of benzene series. Metabolites and parent structures of medicines: methodical instructions for 1st year students’ self-work in Biological and Bioorganic Chemistry (module 1) / compiled by A.O. Syrovaya, L.G. Shapoval, V.N. Petiunina et al. – Kharkiv: KhNMU, 2014. – 25 p. Compiled by: A.O. Syrovaya, L.G. Shapoval, V.N. Petiunina, E.R. Grabovetskaya, S.A. Nakonechnaya, S.N. Kozub Гідрокси- та оксокислоти. Гетерофункціональні сполуки бензольного ряду. Метаболіти та родоначальники лікарських засобів: метод. вказ. для самостійної роботи студентів 1-го курсу з біол. та біоорг. хімії / уклад. Г.О. Сирова, Л.Г. Шаповал, В.М. Петюніна та ін. − Харків: ХНМУ, 2014. − 25с. Укладачі: Г.О. Сирова, Л.Г. Шаповал, В.М. Петюніна, Є.Р. Грабовецька, С.А. Наконечна, C.М. Козуб 2 Subject I. HETEROFUNCTIONAL COMPOUNDS PARTICIPATING IN THE PROCESSES OF THE METABOLISM. HYDROXY- AND OXOACIDS Motivational characteristic of the subject Studying of the structure and chemical properties of the heterofunctional compounds (hydroxy-and oxoacids) is a basis for understanding metabolic process in the living organism. Numerous redox processes in the organism are associated with formation and participation of hydroxy- and oxoacids (oxidation of carbohydrates and fatty acids in the organism, formation of citric acid in Krebs cycle, etc.).
    [Show full text]
  • Functional Derivatives of Carboxylic Acids
    14 Functional Derivatives of Carboxylic Acids Macrophotograph of the fungus Penicillium notatum growing on a petri dish culture of Whickerman’s agar. This fungus was used as an early source of the first penicillin antibiotic. Inset: A model of amoxicillin, a compound that contains two amide functional groups. Amides are functional derivatives of carboxylic acids. (Andrew McClenaghan/Photo Researchers, Inc.) KEY QUESTIONS 14.1 What Are Some Derivatives of Carboxylic Acids, and HOW TO How Are They Named? 14.1 How to Name Functional Derivatives 14.2 What Are the Characteristic Reactions of Carboxylic of Carboxylic Acids Acid Derivatives? 14.2 How to Approach Multistep Synthesis Problems 14.3 What Is Hydrolysis? 14.4 How Do Carboxylic Acid Derivatives React with CHEMICAL CONNECTIONS Alcohols? 14A Ultraviolet Sunscreens and Sunblocks 14.5 How Do Carboxylic Acid Derivatives React with 14B From Moldy Clover to a Blood Thinner Ammonia and Amines? 14C The Penicillins and Cephalosporins: B-Lactam 14.6 How Can Functional Derivatives of Carboxylic Antibiotics Acids Be Interconverted? 14D The Pyrethrins: Natural Insecticides 14.7 How Do Esters React with Grignard Reagents? of Plant Origin 14.8 How Are Derivatives of Carboxylic Acids Reduced? 14E Systematic Acquired Resistance in Plants IN THIS CHAPTER, we study four classes of organic compounds, all derived from the car- boxyl group: acid halides, acid anhydrides, esters, and amides. Under the general formula of each functional group is a drawing to help you see how the group is formally related to
    [Show full text]