DOCSLIB.ORG

Uva-DARE (Digital Academic Repository)

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Uva-DARE (Digital Academic Repository) UvA-DARE (Digital Academic Repository) Studies towards Syntheses of Enantiopure 1-Azaadamantane-2-carboxylic Acid Derivatives. Verhaar, M.T. Publication date 2000 Link to publication Citation for published version (APA): Verhaar, M. T. (2000). Studies towards Syntheses of Enantiopure 1-Azaadamantane-2- carboxylic Acid Derivatives. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:27 Sep 2021 CHAPTERR 1 1-AZAADAMANTANE-2-CARB0XYLICC ACID DERIVATIVES 1.11 General Introduction Fromm ancient times mankind has used plants for the preparation of potions with healing, poisoningg or magic power. Many of the biologically active ingredients from these plant extracts,, as far as they have been identified, belong to the compound class of the alkaloids. The termm 'alkaloid' was first proposed by the pharmacist W. Meissner in 1819, meaning 'alkali-like'. Onlyy recently, modern chemistry gained knowledge of the chemical structure of alkaloids, whichh are by definition basic, nitrogen-containing compounds of plant origin (with a complex molecularr structure) which manifest significant pharmacological activity. The nitrogen atom is usuallyy in a ring which is often part of a complex polycyclic system. Nicotine 1, cocaine 2 and strychninee 3' are some examples of well-known alkaloids that display reputed pharmacological activity.2 2 Mee fONN NN ^^, l^fv, | /-^^ l\_ /X52Me \\ I f Ü 1 1 M HH Me /^OCOPh O"^"^O nn H nicotinee 1 cocaine 2 strychnine 3 1-azaadamantane 4 Thee synthesis of alkaloids, derivatives thereof and structurally related compounds has gainedd considerable chemical interest, due to their pharmacological potency. An example of a structurallyy appealing and alkaloid-related synthetic structure is the 1-azaadamantane 4. This 4a conformationallyy restricted tertiary amine is strongly basic (pKb = 2.96) and several reports onn the pharmacological activity5'6 of derivatives of 1-azaadamantane have been published. In addition,, 1-azaadamantane has been used as a rigid model for heterolytic fragmentation, intramolecularr charge transfer,8 gas-phase basicity9 and NMR studies.10 Compoundss with an 1-azaadamantane skeleton have not yet been isolated from natural sources.. However, during the course of biomimetic studies towards Aristotelia alkaloids the bridgedd 1-azaadamantane 7" was isolated from the acid-catalysed transformation of synthetic (-)-hobartinee 5 into (+)-aristoteline 6 to corroborate the absolute configuration of 6 (eq 1.1). Thee formation of 7 was rationalised by assuming that C-3 instead of C-18 of the starting l l ChapterChapter 1 materiall is protonated to yield the corresponding indolenine cation, which is attacked by the doublee bond (C-18) to give an intermediate dihydroindole derivative. A consecutive nucleophilicc displacement at C-2 of the protonated N-l by the nitrogen atom of the azabicyclononanee resulted in the formation of the bridged 1-azaadamantane 7. Borschberg suggestedd that it is possible that this transformation also occurs in the Aristotelia plant tissue, providedd that a suitable enzyme is present. (1.1) ) 20%% HCI aq H2N N reflux,, 8 h -)-hobartinee 5 (+)-aristotelinee 6 (70%) neohobartine 7 (15%) Fromm the New Zealand plant Aristotelia fruticosa another interesting aristoteline alkaloid,, (+)-aristofruticosine 8 was isolated by Bick et al.n This alkaloid contains a norazaadamantanee skeleton which strongly resembles 1-azaadamantane, but lacks one bridging methylene.. An enantiopure total synthesis of this alkaloid by Borschberg et al.13 confirmed the structuree and established the absolute configuration. n n 99 10 (+)-aristofruticosinee 8 Thee norazaadamantane core (9) found in (+)-aristofruticosine 8 has also been synthesisedd in our research group,4 while the isomeric norazaadamantane 10 has been synthesisedd by Becker and Flynn et al.6 in enantiopure form. It was shown that the (nor)azaadamantanee part of benzamides 12 and 13 mimics the 2-aminoethyl substituent of serotoninn 11, while the benzamide portion is viewed as an indole isostere. The benzamide 13 provedd to be the more potent agonist for the serotonine receptors 5-HT3 and 5-HT4, probably duee to the somewhat smaller volume and even more basic character of the norazaadamantane (pKbb = 2.61)4a compared to the parent azaadamantane (pIQ, = 2.96).4a N-- RHN7^T7 7 CIYV>yy > =R KfeN^^XlMe e RNH H serotoninn 11 12 2 13 3 l-Azaadamantane-2-carboxyücl-Azaadamantane-2-carboxyüc acid derivatives 1.22 Synthesis of 1-azaadamantanes Thee first synthetic efforts14 to obtain 1-azaadamantane started from trimesic acid 14 (eq 1.2).. This compound was converted in several steps into the ds-cyclohexane derivative 15, whichh upon treatment with ammonia in methanol at high temperature and under high pressure resultedd in the formation of small amounts of 1 -azaadamantane 4. Br V V f NH3, MeOH (1.2) ) 15 5 144 C02H Thee method published by Speckamp et al}5 in the seventies allowed the formation of functionalisedd 1-azaadamantanes in larger quantities (eq 1.3). The key step of this procedure wass the condensation of ethyl p\P'-dibromoisobutyrate with the pyrrolidine enamine of N- tosylpiperidonee 16, which afforded 3-azabicyclo[3.3.1]nonane 17 in good yield. Subsequent transformationn into alcohols 18 and treatment with HCl/AcOH afforded the 1-azaadamantanes 19. (1.3) ) NT 0H H f/ V HCl/AcOH H —— ^H /-C02Et RR 18 177 (80%) H RR = H, OH, NH2 Thiss method was extended to the synthesis of quinine (23) analogs16 such as 22. Cyclisationn of 20 in HCl/AcOH afforded the adamantane 21 which upon a Wittig reaction of thee corresponding free ketone and oxidation of C-l 1 led to the quinine analog 22. (1.4) ) ChapterChapter 1 AA very short synthesis of a 1 -azaadamantane was presented by Khuong-Huu et al (eq 1.5).. The a- or P-pinene derived amine 24 smoothly underwent a double Mannich reaction by treatmentt with aqueous formaldehyde and acid catalysis, to yield the adamantane 25. A similar doublee Mannich reaction was applied by Black18 for the synthesis of azaadamantanone8a'18(se e e Sectionn 5.1). """ H20 (1.5) ) CH20 0 dioxane/H20, , ^ ^ A A OH H ^NH2 2 24 4 255 (80%) Rischh et al. described the triple Mannich reaction of substituted 1,3- cyclohexanedioness 26 with hexamethylenetetramine to afford various l-azaadamantane-4,6- dioness 27, which were deoxygenated to give the corresponding 3,5,7-substituted 1- azaadamantaness (eq 1.6). Recently, Risch and Molm20 published the resolution of two racemic l-azaadamantane-3-carboxylicc esters 28 with PLE, which led to the optically active products in moderatee ee's. hexamethylene-- N-- N-- (1.6) ) tetramine e PLEE resolution R1 1 C02Me e o'o' R 28 8 26 6 27 7 :: O: 54% ee :: H, H': 82% ee 1.33 Synthesis of l-azaadamantane-2-carboxylic acid derivatives Derivativess of l-azaadamantane-2-carboxylic acid 30 are all conformational^ constrainedd tertiary oc-amino acids. Well over 500 oc-amino acids have been identified in nature,, showing that this compound class is much more diverse than the 20 amino acids that commonlyy occur in living systems.21 The adamantane amino acid is a very peculiar amino acid becausee the nitrogen is not available for amide bond formation, although the adamantane- *yy*yy tyfy *yy nitrogenn may be quaternised with methyl iodide, allyl bromide, benzyl bromide or chloroaceticc acid23 for example. In spite of their appealing structure and possible applications forr the preparation of biologically active compounds only two racemic syntheses of such compoundss have appeared in the literature.24'25 The first example was published by Wahl et l-Azaadamantane-2-carboxylicl-Azaadamantane-2-carboxylic acid derivatives al.al.2424 (eq 1.7). Using the methodology developed in the group of Speckamp,15 tosylamide 29 wass refluxed in a mixture of concentrated aqueous HC1 and AcOH, to effect the cyclisation to thee adamantane, which was followed by in situ hydrolysis of the cyanide to give the acid 30. ,C02H H refluxx /X^T 30 0 Thee second synthesis, performed in our research group25 proceeded via a Mannich reactionn of azabicyclo[3.3.1]nonene 31 and methyl glyoxylate, affording the two diastereomericc adamantanes 32 in moderate yield (see Section 2.1). r7~~~~\r7~~~~\ Me02CCHO(MeOH) NHH HCÖÖhh - /^'N (1-8) thenn basic work up 311 H C02Me 322 (35%) 1.44 Present synthetic strategies towards l-azaadamantane-2-carboxylic acid derivatives s Thee present investigation is aimed at the synthesis of enantiopure l-azaadamantane-2- carboxylicc acid derivatives. The synthetic strategies to arrive at the adamantane skeleton can be dividedd into two general approaches, as outlined in Scheme 1.1. The adamantane 33 is broken downn retrosynthetically via a Mannich reaction to either the azabicyclononene 34, analogous to thee aforementioned synthesis, or the azabicyclononane-2-carboxylic ester 35. These two intermediatess might be synthesised from enantiopure cyclohexenemethylamines like 36. NH H % % 34 4 approachh 1 NH 2H 2 approachh 2 36 355 C02R ChapterChapter 1 Thee second approach is considered to be the most promising due to the expected stereoselectivee Mannich reaction of 35 with formaldehyde, whereas such a reaction of 34 with aa glyoxylic acid derivative will presumably lead to mixtures of two diasteromeric adamantanes.
Load more

Recommended publications
  • 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.
    [Show full text]
  • Studying Interfacial Dark Reactions of Glyoxal and Hydrogen Peroxide Using Vacuum Ultraviolet Single Photon Ionization Mass Spectrometry
    atmosphere Article Studying Interfacial Dark Reactions of Glyoxal and Hydrogen Peroxide Using Vacuum Ultraviolet Single Photon Ionization Mass Spectrometry Xiao Sui 1,2 , Bo Xu 3, Jiachao Yu 2, Oleg Kostko 3, Musahid Ahmed 3 and Xiao Ying Yu 2,* 1 College of Geography and Environment, Shandong Normal University, Jinan 250358, China; [email protected] 2 Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA 99354, USA; [email protected] 3 Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, CA 94720, USA; [email protected] (B.X.); [email protected] (O.K.); [email protected] (M.A.) * Correspondence: [email protected] Abstract: Aqueous secondary organic aerosol (aqSOA) formation from volatile and semivolatile organic compounds at the air–liquid interface is considered as an important source of fine particles in the atmosphere. However, due to the lack of in situ detecting techniques, the detailed interfacial reaction mechanism and dynamics still remain uncertain. In this study, synchrotron-based vacuum ultraviolet single-photon ionization mass spectrometry (VUV SPI-MS) was coupled with the System for Analysis at the Liquid Vacuum Interface (SALVI) to investigate glyoxal dark oxidation products at the aqueous surface. Mass spectral analysis and determination of appearance energies (AEs) suggest that the main products of glyoxal dark interfacial aging are carboxylic acid related oligomers. Citation: Sui, X.; Xu, B.; Yu, J.; Furthermore, the VUV SPI-MS results were compared and validated against those of in situ liquid Kostko, O.; Ahmed, M.; Yu, X.Y. time-of-flight secondary ion mass spectrometry (ToF-SIMS). The reaction mechanisms of the dark Studying Interfacial Dark Reactions glyoxal interfacial oxidation, obtained using two different approaches, indicate that differences in of Glyoxal and Hydrogen Peroxide ionization and instrument operation principles could contribute to their abilities to detect different Using Vacuum Ultraviolet Single oligomers.
    [Show full text]
  • Method of Preparing Vanillin
    (19) TZZ¥Z_T (11) EP 3 045 444 A1 (12) EUROPEAN PATENT APPLICATION published in accordance with Art. 153(4) EPC (43) Date of publication: (51) Int Cl.: 20.07.2016 Bulletin 2016/29 C07C 47/58 (2006.01) (21) Application number: 15750614.8 (86) International application number: PCT/CN2015/085408 (22) Date of filing: 29.07.2015 (87) International publication number: WO 2016/000664 (07.01.2016 Gazette 2016/01) (84) Designated Contracting States: • LIU, Zhenjiang AL AT BE BG CH CY CZ DE DK EE ES FI FR GB Jiaxing City, Zhejiang 314000 (CN) GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO • YAO, Yueliang PL PT RO RS SE SI SK SM TR Jiaxing City, Zhejiang 314000 (CN) Designated Extension States: • WANG, Chaoyang BA ME Jiaxing City, Zhejiang 314000 (CN) Designated Validation States: • WU, Jianxin MA Jiaxing City, Zhejiang 314000 (CN) • ZHAO, Feifei (30) Priority: 30.06.2014 CN 201410304472 Jiaxing City, Zhejiang 314000 (CN) (71) Applicant: JIAXING ZHONGHUA CHEMICAL CO., (74) Representative: Johnson, Richard Alan et al LTD. Mewburn Ellis LLP Nanhu District City Tower Jiaxing City, 40 Basinghall Street Zhejiang 314000 (CN) London EC2V 5DE (GB) (72) Inventors: Remarks: • MAO, Haifang A request for restoration of the right of priority under Jiaxing City, Zhejiang 314000 (CN) Rule 49ter.2 PCT is pending before the EPO as • WANG, Lizhi designated Office. Jiaxing City, Zhejiang 314000 (CN) (54) METHOD OF PREPARING VANILLIN (57) A method of preparing vanillin comprises weigh- water with the volume ratio of water to the first solvent ing eugenol, a strong alkali,
    [Show full text]
  • Dissociation Constants of Organic Acids and Bases
    DISSOCIATION CONSTANTS OF ORGANIC ACIDS AND BASES This table lists the dissociation (ionization) constants of over pKa + pKb = pKwater = 14.00 (at 25°C) 1070 organic acids, bases, and amphoteric compounds. All data apply to dilute aqueous solutions and are presented as values of Compounds are listed by molecular formula in Hill order. pKa, which is defined as the negative of the logarithm of the equi- librium constant K for the reaction a References HA H+ + A- 1. Perrin, D. D., Dissociation Constants of Organic Bases in Aqueous i.e., Solution, Butterworths, London, 1965; Supplement, 1972. 2. Serjeant, E. P., and Dempsey, B., Ionization Constants of Organic Acids + - Ka = [H ][A ]/[HA] in Aqueous Solution, Pergamon, Oxford, 1979. 3. Albert, A., “Ionization Constants of Heterocyclic Substances”, in where [H+], etc. represent the concentrations of the respective Katritzky, A. R., Ed., Physical Methods in Heterocyclic Chemistry, - species in mol/L. It follows that pKa = pH + log[HA] – log[A ], so Academic Press, New York, 1963. 4. Sober, H.A., Ed., CRC Handbook of Biochemistry, CRC Press, Boca that a solution with 50% dissociation has pH equal to the pKa of the acid. Raton, FL, 1968. 5. Perrin, D. D., Dempsey, B., and Serjeant, E. P., pK Prediction for Data for bases are presented as pK values for the conjugate acid, a a Organic Acids and Bases, Chapman and Hall, London, 1981. i.e., for the reaction 6. Albert, A., and Serjeant, E. P., The Determination of Ionization + + Constants, Third Edition, Chapman and Hall, London, 1984. BH H + B 7. Budavari, S., Ed., The Merck Index, Twelth Edition, Merck & Co., Whitehouse Station, NJ, 1996.
    [Show full text]
  • Glyoxylate Cycle: Steps and Significance
    Glyoxylate Cycle: Steps and Significance It had been observed by many plant physiologists that during the germination of fatty seeds, the fat content decreased with a simultaneous increase in sucrose (i.e., carbohydrates). This apparent conversion of fats into sucrose remained a mystery till 1957 when Kornberg and Krebs discovered that a strain of bacterium Pseudomonas could readily convert 14C-labelled acetic acid into labelled malic acid and citric acid (these are inter mediates of Krebs’ Cycle) which involved the following reactions: (1) Acetyl-CoA combined with Oxaloacetic acid to form Citric Acid. Acetyl-CoA + Oxaloacetic acid → Citric Acid + CoA (Acetic acid first reacted with Coenzyme-A to form Acetyl CoA). (2) Acetyl CoA reacted with glyoxylic acid in the presence of the enzyme malate syn thetase to produce Malic acid. Acetyl CoA + Glyoxylic Acid → Malic Acid + CoA The glyoxylic acid was obtained through the breakdown of Iso-Citric Acid (an inter mediate of Krebs’ Cycle) by the enzyme Isocitratase Isocitric acid → glyoxylic acid + succinic acid On the bases of the above reactions Kornberg and Krebs (1957) framed a cycle which is called as Glyoxylic acid cycle or Glyoxylate Cycle through which the fats could be converted into sucrose (i.e., carbohydrate) during the germination of fatty seeds in plants. The glyoxylate cycle (which is intimately associated with Krebs’ Cycle) is now known to occur in many other bacteria, yeasts, molds, and higher plants and is completed in glyoxysomes, mitochondria and cytosol. Steps Involved in Glyoxylate Cycle: Various steps of this cycle (Fig. 14.3) occurring in higher plants especially during the germination of fatty seeds are as follows: (a) Reactions in Glyoxysome: (i) Acetyl-CoA produced after the β-oxidation of fatty acids (in glyoxysomes) condenses with oxaloacetic acid to form Citric Acid.
    [Show full text]
  • Technological, Commercial, Organizational, and Social Uncertainties of a Novel Process for Vanillin Production from Lignin
    TECHNOLOGICAL, COMMERCIAL, ORGANIZATIONAL, AND SOCIAL UNCERTAINTIES OF A NOVEL PROCESS FOR VANILLIN PRODUCTION FROM LIGNIN by Jason Timothy Wong Bachelor of Science, University of British Columbia, 1992 Doctor of Philosophy, University of Manitoba, 1998 PROJECT SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF BUSINESS ADMINISTRATION In the Management of Technology Program of the Faculty of Business Administration © Jason Timothy Wong 2012 SIMON FRASER UNIVERSITY Fall 2012 All rights reserved. However, in accordance with the Copyright Act of Canada, this work may be reproduced, without authorization, under the conditions for Fair Dealing. Therefore, limited reproduction of this work for the purposes of private study, research, criticism, review and news reporting is likely to be in accordance with the law, particularly if cited appropriately. i Approval Name: Jason Timothy Wong Degree: Master of Business Administration Title of Project: Technological, Commercial, Organizational, and Social Uncertainties of a Novel Process for Vanillin Production From Lignin Supervisory Committee: __________________________________________ Dr. Pek-Hooi Soh Senior Supervisor Associate Professor, Technology Management & Strategy __________________________________________ Dr. Jill Shepherd Second Reader Adjunct Professor, Technology and Operations Management & Policy Date Approved: __________________________________________ ii Abstract Lignin is a potentially rich source of aromatic compounds. Rhodococcus jostii RHA1 Δvdh was bioengineered to accumulate vanillin when grown on lignin. Certain technological, commercial, organizational and social (TCOS) uncertainties will need to be addressed for RHA1 Δvdh to be successfully adopted for commercial applications. Technologically, opportunities exist to utilize lignin for value-added chemicals. Commercially, entering the competitive vanillin market will be difficult. Opportunities exist to develop differentiated products and offer those products in emerging markets.
    [Show full text]
  • Glyoxylate Cycle
    COMPILED AND CIRCULATED BY PROF. NANDITA BHAKAT, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE. GLYOXYLATE CYCLE It had been observed by many plant physiologists that during the germination of fatty seeds, the fat content decreased with a simultaneous increase in glucose(i.e, carbohydrates). Kornberg and Krebs (1957) framed a cycle which is known as Glyoxylic acid cycle or Glyoxylate Cycle through which the fats could be converted in to sucrose (i.e., carbohydrates) during the germination of fatty seeds in plants. The glyoxylate cycle (which is intimately associated with the Krebs’ cycle) is now known to occur in many other bacteria, yeasts, molds, and in higher plants and is completed in glyoxysomes, mitochondria and cytosol. Various steps of this cycle occuring in higher plants especially during the germination of fatty seeds are as follows: 1) REACTION IN GLYOXYSOME i) Acetyl-CoA produced after the β oxidation of fatty acids condenses with oxaloacetic acid to form citric acid. CH3COCoA Acetyl CoA CH2COOH + Citrate synthase C(OH)COOH + CoA COCOOH CH2COOH CH2COOH +H2O Citric acid Oxaloacetic acid BOTANY: SEM-VI, PAPER-C13T: PLANT METABOLISM, UNIT-5: ATP SYNTHESIS. COMPILED AND CIRCULATED BY PROF. NANDITA BHAKAT, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE. ii) Citric acid is dehydrated to produce cis-aconitic acid in the presence of aconitase. CH2COOH Aconitase CH2COOH C(OH)COOH CCOOH CH2COOH - H2O CHCOOH Citric acid Cis -aconitic acid iii) Cis aconitic acid reacts with one molecule of H2O to form iso-citric acid. CH2COOH CH2COOH CCOOH + H2O CHCOOH CHCOOH CHOHCOOH Cis -aconitic acid Iso-citric acid iv) Iso- citric acid is broken down into glyoxylic acid and succinic acid by the enzyme Isocitratase.
    [Show full text]
  • 4-Hydroxy-Tryptamine Syntheses
    Tryptamines as Ligands and Modulators of the Serotonin 5-HT2A Receptor and the Isolation of Aeruginascin from the Hallucinogenic Mushroom Inocybe aeruginascens Dissertation zur Erlangung des Doktorgrades der Mathematisch-Naturwissenschaftlichen Fakultäten der Georg-August-Universität zu Göttingen vorgelegt von Niels Jensen aus Hamburg Göttingen 2004 D 7 Referent: Prof. Dr. H. Laatsch Korreferent: Prof. D. E. Nichols Tag der mündlichen Prüfung: 4. November 2004 Table of Contents III _________________________________________________________________________ Table of Contents Table of Contents ................................................................................................................III List of Figures...................................................................................................................... V List of Tables ...................................................................................................................... IX List of Abbreviations ...........................................................................................................XI Theoretical Part ....................................................................................................................1 Introduction.......................................................................................................................1 Psychoactive mushrooms.............................................................................................1 Inocybe aeruginascens.................................................................................................3
    [Show full text]
  • Synthesis of Allantoin Catalyzed by SO4 2-/La2o3-Sio2-Zro2
    Asian Journal of Chemistry; Vol. 24, No. 5 (2012), 2298-2300 2- Synthesis of Allantoin Catalyzed by SO4 /La2O3-SiO2-ZrO2 * LIXIU LIU , AIJIANG HE and XIANGBIAO LI Department of Biological and Chemical Engineering, Yibin Vocational and Technical College, Xincun, Cuipingqu, Yibin 644003, Sichuan, P.R. China *Corresponding author: E-mail: [email protected]; [email protected] (Received: 7 June 2011; Accepted: 21 December 2011) AJC-10885 2- Allantoin was synthesized using glyoxalic acid and urea as raw materials and La2O3-promoted solid acid SO4 /SiO2-ZrO2 as catalyst. The present research focused on the effects of La2O3 doping amount, catalyst dosage, reactant ratio and reaction temperature and time on the yield of allantoin. The optimum condition for reactions is as follows: amount of catalyst, 2.5 g; doping amount of La2O3, 0.12 wt %; molar ratio of reactants n(urea): n(glyoxylic acid) = 4:1; reaction temperature, 75 ºC and reaction time, 5 h. The yield of allantoin at optimum condition was up to 46 %. The melting point determination, infrared spectroscopy and elemental analysis of the product confirmed that the obtained product is allantoin and the analysis indicated that the purity was 98.5 % or above. Key Words: Synthsis, Allantoin, Solid acid, La2O3-promoted. INTRODUCTION An energy level with a rich amount of La could absorb the energy released during the reaction. Thus, the energy of the Allantoin is widely used in the pharmaceutical, cosmetic, surface of produced nanoparticles and the conglobation of 1-5 agricultural and biological engineering fields . This comp- these particles will be reduced. This phenomenon indicates ound is an important fine chemical product and its chemical that a proper degree of La doping could suppress the growth synthesis is widely valued.
    [Show full text]
  • Insights from OH Radical Oxidation of Acetic Acid and Methylglyoxal
    Atmos. Chem. Phys., 12, 801–813, 2012 www.atmos-chem-phys.net/12/801/2012/ Atmospheric doi:10.5194/acp-12-801-2012 Chemistry © Author(s) 2012. CC Attribution 3.0 License. and Physics Mechanisms leading to oligomers and SOA through aqueous photooxidation: insights from OH radical oxidation of acetic acid and methylglyoxal Y. Tan1,*, Y. B. Lim1, K. E. Altieri2, S. P. Seitzinger3, and B. J. Turpin1 1Department of Environmental Sciences, Rutgers University, 14 College Farm Road, New Brunswick, NJ 08901, USA 2Department of Geosciences, Princeton University, B80 Guyot Hall, Princeton, NJ 08544, USA 3International Geosphere-Biosphere Programme (IGBP), Lilla Frescativagen¨ 4a, Stockholm, Sweden *now at: Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, 15213, Pennsylvania, USA Correspondence to: B. J. Turpin ([email protected]) Received: 14 June 2011 – Published in Atmos. Chem. Phys. Discuss.: 28 June 2011 Revised: 15 November 2011 – Accepted: 9 January 2012 – Published: 18 January 2012 Abstract. Previous experiments have demonstrated that 1 Introduction the aqueous OH radical oxidation of methylglyoxal pro- duces low volatility products including pyruvate, oxalate and Large uncertainties remain in the predicted impact of sec- oligomers. These products are found predominantly in the ondary organic aerosol (SOA) on air quality, climate and hu- particle phase in the atmosphere, suggesting that methyl- man health (Kanakidou et al., 2005; Hallquist et al., 2009). glyoxal is a precursor of secondary organic aerosol (SOA). While the refined treatment of intermediate volatility organic Acetic acid plays a central role in the aqueous oxidation of compounds (IVOCs) has in some cases brought predicted or- methylglyoxal and it is a ubiquitous product of gas phase ganic aerosol mass into better alignment with measured mass photochemistry, making it a potential “aqueous” SOA pre- (Pye et al., 2010; Jathar et al., 2011), formation of SOA cursor in its own right.
    [Show full text]
  • A Novel Microbial Aldehyde Oxidase Applicable to Production of Useful
    on T ati ech nt n e o l m o r g e Yamada and Isobe, Ferment Technol 2015, 4:1 y F Fermentation Technology DOI: 10.4172/2167-7972.1000116 ISSN: 2167-7972 / Mini Review Open Access A Novel Microbial Aldehyde Oxidase Applicable to Production of Useful Raw Materials, Glycolic Acid and Glyoxylic Acid, from Ethylene Glycol Miwa Yamada and Kimiyasu Isobe* Department of Biological Chemistry and Food Science, Iwate University, Ueda3, Morioka 020-8550, Japan Keywords: Glycolic Acid, Glyoxylic Acid, Ethylene Glycol glycolaldehyde, because the enzyme did not catalyze further oxidation of glycolic acid into glyoxylic acid. This ALOD consisted of three Description different subunits (αβγ structure), in which the α, β, and γ subunits Glycolic acid is an attractive raw material which is used as a were 76 kDa, 36 kDa, and 14 kDa, respectively. These subunits were dyeing and tanning agent in the textile industry, a flavoring agent and similar to a putative molybdenum-binding protein subunit, a putative preservative in the food processing industry, and a skin care agent in FAD-binding subunit, and a putative iron-sulfur-binding subunit of the pharmaceutical industry. It is also utilized for the production of xanthine dehydrogenase from Burkholderia phenoliruptrix BR3459a polyglycolic acid and other biocompatible copolymers. Glycolic acid [4], respectively, indicating that the BurkALOD might belong to the can be isolated from natural sources, such as sugarcane, sugar beets, ALOD group in the xanthine oxidase family. pineapple, or cantaloupe, but it is also chemically synthesized by Microbial ALODs consisting of three different subunits have also hydrogenation of oxalic acid with nascent hydrogen or the hydrolysis been reported from Pseudomonas sp.
    [Show full text]
  • Isoprene Forms Secondary Organic Aerosol Through Cloud Processing
    Environ. Sci. Technol. 2005, 39, 4441-4446 subsequent paper these authors concluded that the atmo- Isoprene Forms Secondary Organic spheric dynamics of 2-methyltetrols and related species was Aerosol through Cloud Processing: not consistent with a homogeneous mechanism and was instead consistent with formation in the aqueous aerosol Model Simulations phase by acid-catalyzed reaction with hydrogen peroxide (8). Enhanced SOA formation through acid-catalyzed reac- tions on particle surfaces has recently been convincingly HO-JIN LIM,² demonstrated (9) and provides a proven mechanism by which ANNMARIE G. CARLTON, AND isoprene can yield SOA (10, 11). In addition, fog/cloud BARBARA J. TURPIN* processing, which is an important source of sulfate, has been Department of Environmental Sciences, Rutgers University, hypothesized to be an important source of SOA (12). 14 College Farm Road, New Brunswick, New Jersey 08901 Compelling recent evidence supports this hypothesis (13- 15). Briefly, reactive organics are oxidized in the interstitial spaces to form highly water-soluble compounds (e.g., al- dehydes) that readily partition into cloud droplets. (OH Isoprene accounts for more than half of non-methane concentrations are elevated in the interstitial spaces of clouds volatile organics globally. Despite extensive experimentation, (16).) The dissolved organics oxidize further to form less homogeneous formation of secondary organic aerosol volatile organics, e.g., organic acids. Upon cloud droplet (SOA) from isoprene remains unproven. Herein, an in- evaporation, these organics remain in the particle phase and cloud process is identified in which isoprene produces SOA. add to the budget of hygroscopic SOA. In this study we demonstrate that isoprene forms hygroscopic SOA through Interstitial oxidation of isoprene produces water-soluble cloud processing.
    [Show full text]