DOCSLIB.ORG

Bromosubstituted Aryl Hydroxamic Acids and Their Analytical Application Towards Some Transition Metals

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Bromosubstituted Aryl Hydroxamic Acids and Their Analytical Application Towards Some Transition Metals INIS-SD-12B SD0000053 BROMOSUBSTITUTED ARYL HYDROXAMIC ACIDS AND THEIR ANALYTICAL APPLICATION TOWARDS SOME TRANSITION METALS. YS submitted Q\em\s\rv/ 1997 PLEASE BE AWARE THAT ALL OF THE MISSING PAGES IN THIS DOCUMENT WERE ORIGINALLY BLANK TO AW PARENTS ****** TO MY CHILDERN ****** TO MY WIFE ******* TO MY BROTHERS AND SISTERS**** A CKNO WLEDGEMENT I would like to express my deepest thanks and gratitude to my supervisor Dr. Hassan Abdelaziz Abdalla for his directions, invaluable advice, encouragement and guidance throughout the course of this study. Thanks are also extended to the staff of Chemistry Department for their help and the Department of Chemistry where this investigation has been carried out, for laboratory facilities and valuable assistance in the use of various equipments. My greateful thanks to my brothers and friends for their assistance and support during the course of my study. Thanks are due to miss Hameeda Elamin for typing this thesis. Finally I would like to thank University of Khartoum for providing the scholarship. ABSTRACT Four aryl substituted hydroxamic acids were prepared: N-phenyl-N-p- bromobenzohydroxamic acid, N-phenyl-N-o-bromobenzohydroxamic acid, p-melhyl-N-phenyl-N-p-bromobenzohydroxamic acid and P-rnethyl-N-phenyl-N- o-bromobenzohydroxamic acid by the reaction of [3-phenylhydroxylamine and p-methyl-P phenylhydroxylamine with the corresponding acid chloride. The acids were identified by their melting points, elemental analysis (nitrogen and bromine contents), infrared and ultraviolet absorption in chloroform, as well as reactions towards acidic solutions of vanadium (V) and iron (III) to give violet and blood- red coloured complexes in the chloroform layer respectively. The extractability of these acids towards chromium (VI), molybdenum (VI), iron (III), vanadium (V), copper (II) and cobalt (II) was investigated . N-phenyl-N-p-bromobenzohydroxamic acid has a maximum extraction for chromium (VI) 96.00 % at IM H2SO4, molybdenum (VI) 87.00 % at pH 1, iron (III) 73.90% at pH 4, vanadium (V) 93.00% at pH 1, cobalt (II) 83.10 at pH 8 and copper (II) 93.80% at pH 6. N-phenyl-N-o-bromobenzohydroxamic acid has a maximum extraction for chromium (VI) 97.00% at IM H2SO4, molybdenum (VI) 92.70% at pH 1, iron (III) 71.20% at pi I 4, vanadium (V) 90.00% at pH 1, cobalt (II) 54.70% at pH 7 and copper (II) 86.50% at pH 5. P-methyl-N-phenyl-N-p-bromobenzohydroxamic acid has a maximum extraction for chromium (VI) 98.70% at IM H2SO4, molybdenum (VI) 74.00% at pH 1, iron (III) 69.60% at pH 5, vanadium (V) 76.00% at pH 1, cobalt (II) 51.20% at pi I 8 and copper (II) 82.20% at pH 5. P-methyl-N-phenyl-N-o-bromobenzohydroxamic acid has a maximum extraction for chromium (VI) 51.00% at IM H2SO4, molybdenum (VI) 84.70% at pi 1 I , iron (III) 66.00% at pH 4, vanadium (V) 88.00% at pH 1, cobalt (II) 50.00% at pi I 7 and copper (II) 78.6% at pH 6. Twenty four of hydroxamic acids complexes of Cr ( VI), Mo (VI), V (V), Fe (III), Co (II) and Cu (II) were prepared by the reaction of these acids with the six metals at different medium. The ratio of the metal to ligand was determined by the continuous variation method and elemental analysis of these complexes. The ratios of Cr (VI), Mo (VI), V(V), Fe (III), Co (II) and Cu (II) were found as follows: 1:2 , 1 : 2, 1 : 1, 1 : I, 1:2 and 1 : 2 respectively. CONTENTS Title -. - i Dedication <i Acknowledgement iii Abstract (English) iv Abstract (Arabic ) vi Contents viii List of Tables xii List of figures and appendices xvi Abbreviations xix CHAPTER ONE: Introduction 1 1.1 Analytical Chemistry 1 i -> Methods of Analysis 1 1.2.1 Chemical Methods 1 , 1.2.2 Physicochemical Methods ." 1 1.3 Solvent Extraction 2 1.3.1 Theories of Solvent Extraction 3 1.3.1 .1 Distribution law 3 1.3.1 .2 Distribution Ratio 4 1.3.1 .3. The Percent Extraction (Recovery ) 6 1.3.1 .4. Successive Extraction 7 1.3.2 Solvent Extraction of Metals 7 1.3.2 .1 Ion Association Complexes 7 1.3.2 -) Metal Chelates 7 1.3.2 .3. Extraction Process 8 1.3.2 .4 The Seperation Efficiency of Metal Chelates 11 1.4. Analytical Seperations 12 1.4.1 Multiple Batch Extraction 12 1.5. Organic Reagents in Analytical Chemistry 14 1.6. Some Applications of Organic Reagents in Analytical Chemistry 15 1.6.1 Gravimetric Analysis 15 1.6.2 Complexing Agents 15 1.6.3 Colourimetric Analysis 16 1.7 Hydroxamic Acids 16 via 1.7.1 Structure of Hydroxamic Acids 16 1.7.2 Preparation of Hydroxamic Acids 18 1.7.3 Properties of Hydroxamic Acids 20 1.7.4. Detection of Hydroxamic Acids 20 1.7.5 Acidity of Hydroxamic Acids 21 1.8. Some Applications of Hydroxamic Acids 24 1.8.1 Gravimetric Determination 24 1.8.2 Hydroxamic Acid Resins 25 1.8.3 Spectrophotometric Determinations 26 1.8.3.1 Stripping 28 CHAPTER TWO: 2. EXPERIMENTAL AND RESULTS 35 2.1 Preparation of Hydroxamic Acids 35 2.1.1 Preparation of N-phenyl-N-benzohydroxamic Acid 35 2.1.1.1 Preparation of P-phenylhydroxylamine 36 2.1.1.2 The coupling Reaction Between P-phenylhydroxylamine and Benzoyl chloride 36 2.1.2 Preparation ofN-phenyl-N-p-bromobenzohydroxamic Acid .... 37 2.1.2.1 Preparation of p-bromobenzoyl chloride 38 2.1.2.2. Preparation of (3-phenylhydroxylamine 38 2.1.2.3 The Coupling Reaction Between P-phenylhydroxylamine and p- bromobenzoyl chloride 38 2.1.3 Preparation of N-phenyl-N-o-bromobenzohydroxamic Acid ... 39 2.1.3.1. Preparation of P-phenylhydroxylamine 39 2.1.3.2. Preparation of o-bromobenzoyl chloride 40 2.1.3.3. The Coupling Reaction Between o-bromobenzoyl chloride and |3- phenyihydroxylamine 40 2.1.4. Preparation of p-methyl-N-phenyl-N-p-bromobenzohydroxamic Acid 40 2.1.4.1 Preparation of p-methyl -N-phenyl hydroxylamine 41 2.1.4.2 Preparation of p-bromobenzoyl chloride 41 2.1.4.3 The Coupling Reaction Between p-bromobenzoyl and P-methyl -N- phenylhydroxylamine 42 2.1.5 Preparation of p-methyl-N-phenyl-N-o-bromobenzohydroxamic Acid 42 2.1.5.1 Preparation ofp-methyl -N-phenylhydroxylamine 42 2.1.5.2 Preparation of o-bromobenzoyl chloride 42 2.1.5.3 The Coupling Reaction Between p-methyl-N-phenylhydroxylamine and o-bromobenzoyl chloride 43 2.2. Characterization of the Four Hydroxamic Acids 43 2.2.1 Their Melting Points 43 2.2.2 Characteristic Colour Reaction 44 2.2.3. Elemental Analysis 44 2.2.3.1. Determination of Nitrogen Content 44 2.2.3.2. Determination of Bromine Content 45 2.2.4 Infrared Spectrosocpy 46 2.2.5 Ultra-violet Absorption 47 2.3. Extraction and Colourimetric Determinations of Molybdenum (VI),Chromium (VI) .Iron (III) Vanadium (V), Cobalt (II) and Copper (II) 49 2.3.1. Extraction and Analysis of Chromium (VI) 49 2.3.1.1. Extraction of Chromium (VI) with N-phenyl-N-p-bromobenzo- hydroxamic Acid 50 2.3.1.2. Preparation of Standard (Calibration ) Curve 50 2.3.1.3. Determination of Chromium (VI) in the Aqueous layer 53 2..3.1.4 Determination of Chromium (VI) in the Organic layer 53 2.3.2. Extraction and Analysis of Molybdenum (VI) 60 2.3.2.1 Extraction of Molybdenum (VI) with N-phenyl-N-p-bromobenzohy droxamic Acid 60 2.3.2.2. The Standard (Calibration) Curve - 60 2.3.2.3. The Determination of Molybdenum (VI) in the Aqueous layer 63 2.3.2.4. The Determination of Molybdenum (VI) in the Organic layer 63 2.3.3. Extraction and Analysis of Iron (III) 68. 2.3.3.1 Extraction of Iron (III) with N-phenyl-N-p-bromobenzohy- droxmic Acid 68 2.3.3.2. The Standard (Calibration) Curve 68 2.3.3.3. The Determination of Iron (III) in the Aqueous layer •. 71 2.3.3.4. The Determination o f Iron (III) in the Organic Layer 71 2.3.4. Extraction and Analysis of Vanadium (V) 77 2.3.4.1 Extraction of Vanadium (V) with N-phenyl-N-p-bromobenzohy- droxamic Acid 77 2.3.4.2. The Standard (Calibration) Curve 78 2.3.4.3. The Determination of Vanadium (V) in the Aqueous layer 80 2.3.4.4. The Determination of Vanadium (V) in the Organic layer 80 2.3.5. Extraction and Analysis of Cobalt (II) 86 2.3.5.1 Extraction of Cobalt (II) with N-phenyl-N-p- bromobenzohydroxamic Acid 86 2.3.5.2 The Standard (Calibration ) Curve 86 2.3.5.3. The Determination of Cobalt (II) in the Aqueous Layer 89 2.3.5.4 The Determination of Cobalt (II) in the Organic Layer 89 2.3.6. Extraction and Analysis of Copper (II) 92 2.3.6.1. Extraction of Copper (II) with N-phenyl-N-p- bromobenzohydroxamic Acid 92 2.3.6.2. The standard (Calibration ) Curve 92 2.3.6.3. The Determination of Copper (II) in the Aqueous Layer 97 2.3.6.4. The Detemination of Copper (II) in the Organic Layer 97 2.4. Metal Complexes 102 2.5. Spectrophotometric Studies on M+n - hydroxamic Acids 105 2.5.1. M+n N-phenyl-N-p-bromobenzohydroxamic Acid Complexes... 105 2.5.1.1.
Load more

Recommended publications
  • The Detection and Determination of Esters
    Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1958 The etD ection and Determination of Esters. Mohd. Mohsin Qureshi Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Qureshi, Mohd. Mohsin, "The eD tection and Determination of Esters." (1958). LSU Historical Dissertations and Theses. 501. https://digitalcommons.lsu.edu/gradschool_disstheses/501 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. Copright by Mohcl Mohsin Qureshi 1959 THE DETECTION AND DETERMINATION OF ESTERS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Chemistry by Mohd. Mohsin Qureshi M.Sc., Aligarh University, 1944 August, 1958 ACKNOWLEDGMENT The author wishes to express his sincere apprecia­ tion and gratitude to Dr. Philip W. West under whose guidance this research was carried out. He is grateful to Dr. James G. Traynham for sup­ plying him with a number of esters and for his many helpful suggestions. The financial support given to him by the Continental Oil Company is gratefully acknowledged. He offers his sincere thanks to Miss Magdalena Usategul for her valuable suggestions and her ungrudging help during the course of this investigation. Dr. Anil K.
    [Show full text]
  • Synthesis of Peptides with Hydroxamic Acid Side Chain Appendages
    University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 12-2003 Synthesis of peptides with hydroxamic acid side chain appendages. Yingchuan Susan Sun 1975- University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Recommended Citation Sun, Yingchuan Susan 1975-, "Synthesis of peptides with hydroxamic acid side chain appendages." (2003). Electronic Theses and Dissertations. Paper 1407. https://doi.org/10.18297/etd/1407 This Master's Thesis is brought to you for free and open access by ThinkIR: The University of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The University of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. SYNTHESIS OF PEPTIDES WITH HYDROXAMIC ACID SIDE CHAIN APPENDAGES By Yingchuan Susan Sun B.S., China Pharmaceutical University, 1997 A Thesis Submitted to the Faculty of the Graduate School of the University of Louisville in Partial Fulfillment of the Requirements for the Degree of Master of Science Department of Chemistry University of Louisville Louiville, Kentucky December, 2003 SYNTHESIS OF PEPTIDES WITH HYDROXAMIC ACID SIDE CHAIN APPENDAGES By Yingchuan Susan Sun A Thesis Approved on April 14, 2003 By the Following Thesis Committee: Arno F. Spatola (deceased) Thesis Director Chairman ii Copyright 2003 by Yingchuan Susan Sun All rights reserved DEDICATION This thesis is dedicated to my graduate advisor Dr. Arno Spatola who spent his whole life in teaching me and other students principles of chemical science III ACKNOWLEDGEMENTS The author would like to express her gratitude and appreciation to her mentor, Dr.
    [Show full text]
  • Syntheses and Therapeutic Potential of Hydroxamic Acid Based Siderophores and Analogues
    Cf”, Rev. 1989, 89. 1563-1579 1563 Syntheses and Therapeutic Potential of Hydroxamic Acid Based Siderophores and Analogues MARVIN J. MILLER Department of Chemistry, Univ6rslfy of Notre Dam, Notre Dame. Indiana 46556 Received March 9, 1989 (Revised Manuscript Received June 15. 1989) Contenfs I. Introduction 1563 11. Synthetic Design and Synthesis of SMerophore 1564 Components A. Simple Hydroxamates 1565 B. Siderophores Containing 1566 1-Amino-w-(hydroxyamino)alkanes C. More Complex Amino Acid Containing 1567 HydroxamatbBased Siderophores and Analogues D. Total Syntheses of Hydroxamate Amino 1569 Acid Based Sierophores and Analogues 111. Siderophores and Siderophore Derivatives as 1575 Antibiotics Marvin J. Miller was born on Jan 29, 1949, in Dickinson. ND. His interest in science was greatly stimulated at Assumption Abbey Prep, a Benedictine monastic high school in Richardton, ND. Un- I. Infroducflon dergraduate research with Professor S. Peter Pappas at North Dakota State University in Fargo. increased his fascination with Iron has played an essential role in the evolution of science, especially organic chemistry. Further studies during his nearly every form of life on earth. Although iron is one Ph.D. work with Professor G. Marc Loudon at Cornell and an NIH postdoctoral position with Professor Henry Rapoport at Ee&eley of the most abundant elements on the planet, its pivotal solidified an interest in bioorganic chemistry. Since joining the role depended on the development of effective methods faculty at #m University of Notre Dame in 1977, Dr. Miller has been for its assimilation. Ionic forms of iron, especially an A. P. Sloan Fellow, an NIH research career development iron(III), its most common state, are very insoluble awardee, and a Visiting Fellow at #m Australian National University.
    [Show full text]
  • DESIGN and SYNTHESIS of CHELATING COMPOUNDS and SOLID-SUPPORTED CHELATORS for METAL DEPLETED SOLUTIONS Surendra Dawadi University of Missouri-St
    University of Missouri, St. Louis IRL @ UMSL Dissertations UMSL Graduate Works 7-25-2014 DESIGN AND SYNTHESIS OF CHELATING COMPOUNDS AND SOLID-SUPPORTED CHELATORS FOR METAL DEPLETED SOLUTIONS Surendra Dawadi University of Missouri-St. Louis, [email protected] Follow this and additional works at: https://irl.umsl.edu/dissertation Part of the Chemistry Commons Recommended Citation Dawadi, Surendra, "DESIGN AND SYNTHESIS OF CHELATING COMPOUNDS AND SOLID-SUPPORTED CHELATORS FOR METAL DEPLETED SOLUTIONS" (2014). Dissertations. 230. https://irl.umsl.edu/dissertation/230 This Dissertation is brought to you for free and open access by the UMSL Graduate Works at IRL @ UMSL. It has been accepted for inclusion in Dissertations by an authorized administrator of IRL @ UMSL. For more information, please contact [email protected]. DESIGN AND SYNTHESIS OF CHELATING COMPOUNDS AND SOLID-SUPPORTED CHELATORS FOR METAL DEPLETED SOLUTIONS By SURENDRA DAWADI Master of Science (Chemistry), 2010 A DISSERTATION Submitted to the Graduate School of the UNIVERSITY OF MISSOURI - ST. LOUIS In partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY in CHEMISTRY August, 2013 Dissertation Committee Prof. Christopher D. Spilling, Ph.D. (Advisor) Prof. Wesley R. Harris, Ph.D. Prof. Alexei V. Demchenko, Ph.D. Prof. James J. O’Brien, Ph.D. Dawadi, Surendra, 2013, UMSL, p.ii ACKNOWLEDGEMENTS Foremost, I would like to express my profound gratitude to my mentor Professor Christopher D. Spilling for his guidance, encouragement, enthusiastic support, and useful critiques during these past five years. He has always been motivating, encouraging, and enlightening. Dr. Spilling’s humor and friendly sarcasm allowed me to laugh, lightening my perspective when I became too serious.
    [Show full text]
  • Hydroxamic Acids and Their Porous Materials
    Hydroxamic Acids and Their Porous Materials Hayley Rebecca Green A thesis submitted for the Degree of Doctor of Philosophy. School of Engineering and Physical Sciences. Heriot-Watt University. January 2018 The copyright in this thesis is owned by the author. Any quotation from the thesis or use of any of the information contained in it must acknowledge this thesis as the source of the quotation or information. Abstract This thesis aims to provide better understand of the supramolecular synthons of hydroxamic acids and the design rules associated with the porous materials based on hydroxamic acids. Also studied was how synthesis routes influcence the self-assembaly process and the properties of the materials produced. Using a range of analytical techniques, including thermogravimetric analysis, pair distribution function and X-ray diffraction, the structure, design and supramolecular synthons of hydroxamic acids have been studied. By determining the supramolecular synthons of hydroxamic acids the successful production of cocrystals was accomplished. By better understanding the coordination of hydroxamates to metals we have formed two solvates of an eight coordinate Zirconium1[hydroxamate]4 complex. The design rules for the formation of intrinsically and extrinsically porous M4[hydroxamate]6 tetrahedra have also been explored. Using crystal engineering principles it has been possible to produce a series of materials with increasing amounts of extrinsic porosity.The host:guest chemistry of the M4L6 tetrahdera has been studied. The host:guest properties of a family of coordination polymers and macrocycles were also studied. The materials were synthesised via mechanochemical synthesis and solution state crystallisation, with the aim of understanding how the synthetic method affects the host:guest properties of the material.
    [Show full text]
  • Review in Carboxylic Acids and Its Derivatives
    IASET: International Journal of Agricultural & Bio-Chemical Science (IASET: IJABS) ISSN(P): Applied; ISSN(E): Applied Vol. 1, Issue 1, Jan - Jun 2017, 49-66 © IASET REVIEW IN CARBOXYLIC ACIDS AND ITS DERIVATIVES NAGHAM MAHMOOD ALJAMALI Organic Chemistry, Department of Chemistry, College of Education ABSTRACT Carboxylic acids are widespread in nature, often combined with other functional groups. Simple alkyl carboxylic acids, composed of four to ten carbon atoms, are liquids or low melting solids having very unpleasant odors. The fatty acids are important components of the bio molecules known as lipids, especially fats and oils. As shown in the following table, these long-chain carboxylic acids are usually referred to by their common names, which in most cases reflect their sources. They occur widely in nature and have many industrial and pharmaceutical applications like drugs KEYWORDS: Carboxyl, Acid, Test, Acid Derivatives INTRODUCTION Carboxylic acid is a class of organic compounds in which a carbon (C) atom is bonded to an oxygen (O) atom by a double bond and to a hydroxyl group (−OH) by a single bond. A fourth bond links the carbon atom to a hydrogen (H) atom or to some other univalent combining group. The carboxyl (COOH) group is so-named because of the carbonyl group (C=O) and hydroxyl group. The IUPAC name of a carboxylic acid is derived from that of the longest carbon chain that contains the carboxyl group by dropping the final -e from the name of the parent alkane and adding the suffix -oic followed by the word “acid.” The chain is numbered beginning with the carbon of the carboxyl group.
    [Show full text]
  • Development of Synthetic Methodologies Towards Cyclic
    DEVELOPMENT OF SYNTHETIC METHODOLOGIES TOWARDS CYCLIC HYDROXAMIC ACID-BASED NATURAL PRODUCTS BY RANJAN BANERJEE A Dissertation Submitted to the Graduate Faculty of WAKE FOREST UNIVERSITY GRADUATE SCHOOL OF ARTS AND SCIENCES in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY Chemistry December 2010 Winston-Salem, North Carolina Approved By: S. Bruce King, Ph.D., Advisor Pradeep K. Garg, Ph.D., Chairman Rebecca W. Alexander, Ph.D. Christa L. Colyer, Ph.D. Paul B. Jones, Ph.D. ACKNOWLEDGEMENTS I want to express my thanks and sincere gratitude to Dr. S. Bruce King, for all his academic support and chemistry help, support, and advising throughout my Ph.D career. I owe him a lot for helping me develop into an organic chemisty, guiding my projects and his patience in helping me improve my scientific writing. I am really fortunate to have shared his immense scientific knowledge and learn from his amazing mentoring ability. I am also thankful to Dr. Paul Jones and Dr. Rebecca Alexander for being my committee members. I really want to thank Dr. Cynthia S. Day for crystallographic help and Dr. Marcus W. Wright for NMR assistance. They have always been extremely helpful with any data interpretation and experiment setup needed. I thank my previous lab mates Dr. Sarah Knaggs, Dr. Weibin Chen, Dr. Mike Gorczyski, Brad Poole and the present lab mates Mai Shoman, Raje Mukherjee, Dr. Richard Macri, Dr. Mallinath Hadimani, Dr. Susan Mitroka, Craig Clodfelter, Julie Reisz and Jenna DuMond for their assistance and friendship. I appreciate the friendship and support I received from my Wake Forest friends Tanya Pinder, Dr.
    [Show full text]
  • Hydroxamate, a Key Pharmacophore Exhibiting a Wide Range of Biological Activities
    Send Orders of Reprints at [email protected] Mini-Reviews in Medicinal Chemistry, 2013, 13, 000-000 1 Hydroxamate, a Key Pharmacophore Exhibiting a Wide Range of Biological Activities Samuel Bertrand1, Jean-Jacques Hélesbeux1, Gérald Larcher2 and Olivier Duval1,* 1Laboratoire des Substances d’Origine Naturelle et Analogs Structuraux, UPRES-EA 921, SFR 4207 QUASAV, UFR des Sciences Pharmaceutiques et ingénierie de la santé, Université d’Angers, 16 Bd Daviers, 49045 Angers Cedex, France; 2Groupe d'Etude des Interactions Hôte-Pathogène, UPRES-EA 3142, IFR 132, Université d’Angers, Institut de Biologie en Santé PBH-IRIS CHU 4, Rue Larrey 49933 Angers Cedex, France Abstract: Naturally occurring hydroxamic acid derivatives are biosynthesized by microorganisms (siderophores) and plants (benzoxazinoids). Recent developments in drug discovery have highlighted the numerous biological and pharmacological properties that the hydroxamic acid function may possess, leading to therapeutic applications. These properties may be explained by its ability to chelate metals via the presence of two oxygen atoms. Their pharmacological activities can be divided into three groups. The first concerns the ability of these hydroxamic acid derivatives to scavenge metals (particularly iron), which leads to antioxidant, antimicrobial and metal detoxification activities. The latter is largely used to treat iron overload in patients. The second group of activities is related to their ability to inhibit metallo-enzymes, which gives them a wide range of pharmacological effects: antimicrobial, anti-inflammatory and antitumor. The third group is linked to the capacity of these compounds to generate nitric oxide, which confers hypotensive activity. However, hydroxamates exhibit relatively low stability in vivo, which can be overcome by the synthesis of appropriately designed analogs.
    [Show full text]
  • Proceedings of the Indiana Academy of Science 3 3 (1994) Volume 103 (1-2) P
    Proceedings of the Indiana Academy of Science 3 3 (1994) Volume 103 (1-2) p. 33-46 THE CHEMICAL CHARACTERIZATION OF ORGANIC FUNCTIONAL GROUPS: AN EXPERIMENT FOR THE ADVANCED HIGH SCHOOL CHEMISTRY LABORATORY John A. Ricketts Department of Chemistry DePauw University Greencastle, Indiana 46135 ABSTRACT: The time limitation placed on laboratory activities, the use of flammable solvents and corrosive chemicals, and the need for expensive glassware precludes the use of extensive organic synthesis in the high school laboratory. A scheme is presented in this paper to identify chemically whether a pure organic, mono-functional compound is a carboxylic acid, acid anhydride, alcohol, aldehyde, amide, amine, ester, ether, ketone, phenol, or hydrocarbon. The classification reactions are performed on a semimicro scale using inexpensive reagents. The experiment is written as an "open-ended" project that requires each student to make decisions that are based upon individual observations. KEYWORDS: Organic chemistry, laboratory experiments, functional groups, chemical characterization. INTRODUCTION An introduction to organic functional group chemistry is now a part of many college-level, introductory chemistry courses, especially the course for the non-science major and, to a lesser extent, the chemistry course for the science major. Therefore, units emphasizing organic chemistry have a place within the advanced high school chemistry course. Many of the organic syntheses that are done at the college level require the use of corrosive reagents, appreciable amounts of starting materials, flammable and toxic solvents, and expensive glassware. Furthermore, their completion requires longer than 50 minutes. Such constraints limit the number of organic synthesis experiments, in which products are isolated, purified, and characterized, that are amenable for use in high school.
    [Show full text]
  • Catalytic Asymmetric Synthesis of CF3-Substituted Tertiary Propargylic Alcohols Via Direct Aldol Cite This: Chem
    Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue Catalytic asymmetric synthesis of CF3-substituted tertiary propargylic alcohols via direct aldol Cite this: Chem. Sci.,2017,8,3260 reaction of a-N3 amide† Hidetoshi Noda, Fuyuki Amemiya, Karin Weidner, Naoya Kumagai* and Masakatsu Shibasaki* Organofluorine compounds are found in several important classes of chemicals, such as pharmaceuticals, agrochemicals, and functional materials. Chemists have been immensely interested in the development of methodologies for expeditious access to fluorine containing building blocks. In this study, we report a new method for the catalytic asymmetric synthesis of CF3-substituted tertiary propargylic alcohols with two contiguous stereogenic centers via the direct aldol reaction of an a-N3 amide to trifluoromethyl ketones. The key to the success of this method is the identification of a catalyst comprising Cu(II)/chiral hydroxamic acid to promote the desired aldol reaction, constructing a tetrasubstituted carbon in a highly Creative Commons Attribution 3.0 Unported Licence. stereoselective fashion. Despite substantial prior advances in asymmetric catalysis, this class of catalysts has not been utilized for the formation of carbon–carbon bond-forming reactions. Our mechanistic Received 23rd January 2017 study sheds light on the unique profile of this catalytic system, where the Cu(II) complex plays Accepted 21st February 2017 a bifunctional role of serving as a Lewis acid and a Brønsted base. Furthermore, the densely DOI: 10.1039/c7sc00330g
    [Show full text]
  • Studies on the Synthesis and Structures of Hydroxamic Acids And
    International Journal of Applied Research 2018; 4(2): 35-39 ISSN Print: 2394-7500 ISSN Online: 2394-5869 Studies on the synthesis and structures of hydroxamic Impact Factor: 5.2 IJAR 2018; 4(2): 35-39 acids and their activities in chemistry and biology www.allresearchjournal.com Received: 27-09-2017 Accepted: 29-01-2018 Dr. Surendra Prasad Singh Dr. Surendra Prasad Singh Associate Professor, Abstract Department of Chemistry A hydroxamic acid is a class of organic compounds bearing the functional group RC(O)N(OH)R', with Amrit Campus, Tribhuvan R and R' as organic residues and CO as a carbonyl group. They are amides (RC(O)NHR') wherein the University, Kathmandu, Nepal NH center has an OH substitution. Hydroxamic acids are hydrophilic organic compounds that can exhibit keto-iminol tautomerism, and both tautomers may exist as Z (zusammen) or E (Entgegen) diastereomers. They are much weaker acids than the structurally related carboxylic acids RC(=O)OH, and produce hydroxamate ions. The deprotonation could be either from the nitrogen or the oxygen, making them N-acids or O-acids. Hydroxamic acids, having the bidentate functional grouping (I), fulfil the basic requirement of complex formation with metal ions and, therefore, form an important family of chelating agents. Structurally, hydroxamic acids can be represented in their two tautomeric form of type (II) and (III). By substituting the hydrogen atom attached to the nitrogen atom in (II) by alkyl or aryl groups, numerous N-substituted hydroxamic acids of type (IV) can be obtained. The complex formation of hydroxamic acids of type (IV) usually takes place with the replacement of the hydroxylamine hydrogen by the metal ion and ring closure through the carbon oxygen.
    [Show full text]
  • 1.2. Hydroxamic Acids LU.Generah
    SD9900036 Preparation of N-1-naphthyl benzo- andN-phenyl benzo hydroxamic acids and study of their extractibility towards Fe (III), Cr (VI) and U (VI) A thesis submitted BY Sttoum FOR The M.Sc. degree (Chemistry?) Department of chemistry Faculty of Science University of Khartoum, Sudan December 1997 A- 3 0-39 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. I gratefully acknowledge my indebtedness to my supervisor Dr. Hassan Abdel Aziz for his comments, suggestions and directions. I would especially like to record my grateful appreciation of the tremendous amount of private time voluntarily given by him without which this work would not have been easily concluded. I am also indebted to Dr. Tag Elsir Abbas yvho has always been responsive to my queries and also for his valuable help. Last, but not the least I wish to thank all my colleagues and the staff of the department of chemistry for their friendly and cooperative spirit which made my time with them, indeed, a pleasure. 11 Abstract Two aryl hydroxamic acids were prepared; the N-phenyl benzo hydroxamic acid and the N-l- naphthyl benzohyddroxamic acid the first one was prepared by the partial reduction of nitrobenzene to the $-phenyl hydroxylamine and coupling the latter with benzoyl chloride. The reduction was carried out using ammonium chloride and zinc dust; this pair failed after so many attempts to give the N-l-naphthyl hydroxylamine. So the latter was prepared by using a somewhat milder reducing agent; hydrogen sulphide and ammonia gas in absolute alcohol.
    [Show full text]