DOCSLIB.ORG

Catalytic Enantioselective Approaches to the Oxa-Pictet–Spengler Cyclization and Other 3,6-Dihydropyran-Forming Reactions

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Catalytic Enantioselective Approaches to the Oxa-Pictet–Spengler Cyclization and Other 3,6-Dihydropyran-Forming Reactions SYNOPEN2509-9396 Georg Thieme Verlag Stuttgart · New York 2019, 3, 77–90 short review 77 en Syn Open Z. Zhu et al. Short Review Catalytic Enantioselective Approaches to the oxa-Pictet–Spengler Cyclization and Other 3,6-Dihydropyran-Forming Reactions Zhengbo Zhua HO HO Brønsted acid Alafate Adilia OH catalysis O Chenfei Zhaob 0000-0003-3960-3047 up to R Daniel Seidel*a 0000-0001-6725-111X RCHO 99% ee a Center for Heterocyclic Compounds, Department of Chemis- Dual anion-binding OH O try, University of Florida, Gainesville, Florida 32611, USA iminium catalysis [email protected] N N H H b Department of Chemistry, University of California–Berkeley; R Materials Sciences Division, Lawrence Berkeley National Labo- up to 95% ee ratory; Kavli Energy NanoSciences Institute at Berkeley; Berke- ley Global Science Institute, Berkeley, California 94720, USA Received: 24.08.2019 aryl substituent.9 In this Short Review, we provide exam- Accepted after revision: 04.09.2019 ples of asymmetric oxa-Pictet–Spengler cyclizations that Published online: 25.09.2019 DOI: 10.1055/s-0039-1690686; Art ID: so-2019-d0023-r are under substrate control, discuss all known catalytic en- License terms: antioselective variants of the oxa-Pictet–Spengler cycliza- 10 © 2019. The Author(s). This is an open access article published by Thieme under the tion, and provide an overview of other catalytic enanti- terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, oselective reactions that lead to isochromans and tetrahy- permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes or adapted, remixed, dropyrano[3,4-b]indoles. In addition, we outline remaining transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/) challenges in this area. Abstract This Short Review provides an analysis of the state-of-the-art HO Me O i-Pr in catalytic enantioselective oxa-Pictet–Spengler cyclizations. Also dis- O O O O cussed are other catalytic reactions providing access to enantio- HO O O enriched isochromans and tetrahydropyrano[3,4-b]indoles. Context is O OMe MeO C provided and remaining challenges are highlighted. 2 i-Pr OHC (+)-penicisochroman B Key words oxa-Pictet–Spengler cyclization, isochromans, tetrahydro- Me ISO-09 pyrano[3,4-b]indoles, oxocarbenium ions, asymmetric catalysis, ion ilexisochromane pairing HO O Me OMe O N Among compounds containing a 3,6-dihydropyran core, HO H O isochromans and tetrahydropyrano[3,4-b]indoles have cap- N tured particular interest in the synthetic and medicinal N HO chemistry communities. A small selection of compounds PNU-109291 OH containing these core frameworks is shown in Figure 1. The blapsin B isochroman heterocycle is a ubiquitous component of natu- Bn CN ral products often possessing intriguing bioactivities, such 1 2 3 as ilexisochromane, penicisochroman B, and blapsin B. O O O Synthetic isochromans include the antiapoptotic agent ISO- N N N 4 5 Et H Et H Et Me H n-Pr 09 and the 5-HT1D agonist PNU-109291. Examples of bio- CO2H CO2H CO2H active tetrahydropyrano[3,4-b]indoles are the anti-inflam- (S)-etodolac pemedolac HCV-371 matory agent etodolac,6 the potent analgesic agent pe- Figure 1 Examples of naturally occurring and artificial bioactive iso- medolac,7 and the non-nucleoside inhibitor of hepatitis C chromans and tetrahydropyrano[3,4-b]indoles virus HCV-371.8 The perhaps most desirable way to access isochromans and tetrahydropyrano[3,4-b]indoles in a The Pictet–Spengler reaction was discovered in 1911 stereocontrolled fashion is by means of the oxa-Pictet– and involves the HCl-promoted condensation of - Spengler cyclization; a process in which an oxocarbenium phenethylamine and formaldehyde dimethyl acetal to form ion intermediate undergoes ring-closure onto a pendent 1,2,3,4-tetrahydroisoquinoline (Scheme 1).11 The definition SynOpen 2019, 3, 77–90 Georg Thieme Verlag KG, Rüdigerstraße 14, 70469 Stuttgart, Germany 78 Syn Open Z. Zhu et al. Short Review of the Pictet–Spengler reaction was later expanded to Wünsch and Zott only in 1992.14 While it was found that - include cyclizations of imines or iminium ions possessing a phenylethanol can condense directly with formaldehyde or covalently linked aryl group that undergoes substitution paraformaldehyde in the presence of aqueous HCl to form upon ring-closure.12 While the apparently first example of isochroman without the need to first isolate 1, this ap- an oxa-Pictet–Spengler reaction dates back to 1935,13 when proach inadvertently leads to side products containing the synthesis of isochroman from chloroether 1 was dis- chloromethyl groups on the phenyl ring (not shown).14,15 As closed in a patent by Buschmann and Michel (Scheme 1), outlined in Scheme 1, the general mechanism of the oxa- the term oxa-Pictet–Spengler cyclization was coined by Pictet–Spengler reaction involves the formation of an oxo- Biographical Sketches Zhengbo Zhu was born and Prof. Chengjian Zhu. In 2014, he ty of Florida. His research focus- raised in Jiangxi, China. He moved to Rutgers University for es on asymmetric Brønsted acid earned his B.Sc. degree in the his graduate studies, joining the catalysis and redox-neutral -C–H Department of Chemistry and group of Prof. Daniel Seidel. In bond functionalization of cyclic Chemical Engineering at Nan- August of 2017, he moved with amines. jing University working with the Seidel group to the Universi- Alafate Adili was born and nology of China (USTC) working Seidel. In August of 2017, he raised in Xinjiang, China. He with Prof. Liu-Zhu Gong. In moved with the Seidel group to earned his B.Sc. degree in the 2016, he started his Ph.D. re- the University of Florida. His re- Department of Chemistry at the search at Rutgers University un- search focuses on asymmetric University of Science and Tech- der the direction of Prof. Daniel catalysis. Chenfei Zhao was born in Chi- tained his Ph.D. (2017) from He is currently a postdoctoral na in 1989 and received his Rutgers University working on researcher in Prof. Omar M. B.Sc. at Wuhan University of cooperative catalysis under the Yaghi’s lab at UC Berkeley work- Technology in 2012. He ob- direction of Prof. Daniel Seidel. ing on reticular chemistry. Daniel Seidel studied chemis- Sessler, obtaining his Ph.D. in University in 2005 and was pro- try at the Friedrich-Schiller-Uni- 2002. From 2002 to 2005, he moted to Associate Professor in versität Jena, Germany, and at was an Ernst Schering Postdoc- 2011 and Full Professor in 2014. the University of Texas at Austin toral Fellow in the group of Prof. In the summer of 2017, his re- (Diplom 1998). He performed David A. Evans at Harvard Uni- search group moved to the Uni- his graduate studies in the labo- versity. He started his indepen- versity of Florida. ratory of Prof. Jonathan L. dent career at Rutgers SynOpen 2019, 3, 77–90 79 Syn Open Z. Zhu et al. Short Review carbenium ion, followed by ring closure and subsequent sieves in dichloromethane at room temperature, allowing deprotonation/rearomatization. Both the Pictet–Spengler for the isolation of polycyclic product 8 in excellent yield. A cyclization and the oxa-Pictet–Spengler cyclization can be recent example of a Brønsted acid catalyzed diastereoselec- viewed as variants of an intramolecular Friedel–Crafts al- tive oxa-Pictet–Spengler cyclization was reported by Da and kylation.16 In addition, the oxa-Pictet–Spengler cyclization co-workers.22 Tryptophol derivative 9, derived from the en- is mechanistically related to certain types of the Prins reac- antioselective CBS reduction of the corresponding ketone, tion.17 engages benzaldehyde dimethyl acetal in the presence of a catalytic amount of trifluoroacetic acid to furnish tetrahy- Synthesis of 1,2,3,4-tetrahydroisoquinoline (THIQ) by Pictet and Spengler (1911)11 dropyrano[3,4-b]indole 10 in excellent yield and dr. Consis- tent with the expected mechanism of this transformation, HCl (concd) + MeO OMe the ee of product 10 matches that of the starting material 9. NH2 heat, 5–6 h NH (1.6 equiv) THIQ, 36% OMe 3 Me Me 13 Synthesis of isochroman by Buschmann and Michel (1935) O O HCl (concd, 1 equiv) OH O Me O isochroman, 64% * O O 20–40 °C, 2 h N SnCI , THF, rt N H 4 H Me Cl CO R* 1 2 2 4, 59%, de >95% –HCl deprotonation/rearomatization OMe OMe OMe OMe Me ring-closure Cl H CCH(OMe) (2 equiv) O O OH 3 2 O BF3•Et2O (3 equiv) H Cl oxocarbenium Et2O/THF (4:1), rt, 12 h intermediate OMe O OMe O O O Scheme 1 Original reports on the Pictet–Spengler reaction and its ox- 56, 92% ygen analogue, along with its general mechanism HO Bi(OTf)3 (5 mol%) For the majority of the history of the oxa-Pictet–Spengler OBn OBn LiClO4 (3 equiv) reaction, asymmetric variants were limited to cyclizations O O OMe 4Å MS, CH2Cl2, rt, 3.5 h 9 OMe Me of enantioenriched starting materials. Several illustrative Me OTs examples of such diastereoselective oxa-Pictet–Spengler cy- OTs clizations are provided in Scheme 2. A chiral auxiliary based 7 8, 94% approach was reported by Costa et al., utilizing -ketoester 18 3 derived from (–)--pinene. Condensation of tryptophol Ph Ph (2)19 with -ketoester 3 is facilitated by SnCl , resulting in PhCH(OMe)2 (2.5 equiv) 4 TFA (20 mol%) the formation of product 4 with excellent diastereoselectiv- OH O CH Cl , rt, 48 h N 2 2 N ity. Interestingly, the use of BF3 etherate in place of SnCl4 H H Ph provides a 1:1 mixture of product diastereomers.
Load more

Recommended publications
  • Aldrich FT-IR Collection Edition I Library
    Aldrich FT-IR Collection Edition I Library Library Listing – 10,505 spectra This library is the original FT-IR spectral collection from Aldrich. It includes a wide variety of pure chemical compounds found in the Aldrich Handbook of Fine Chemicals. The Aldrich Collection of FT-IR Spectra Edition I library contains spectra of 10,505 pure compounds and is a subset of the Aldrich Collection of FT-IR Spectra Edition II library. All spectra were acquired by Sigma-Aldrich Co. and were processed by Thermo Fisher Scientific. Eight smaller Aldrich Material Specific Sub-Libraries are also available. Aldrich FT-IR Collection Edition I Index Compound Name Index Compound Name 3515 ((1R)-(ENDO,ANTI))-(+)-3- 928 (+)-LIMONENE OXIDE, 97%, BROMOCAMPHOR-8- SULFONIC MIXTURE OF CIS AND TRANS ACID, AMMONIUM SALT 209 (+)-LONGIFOLENE, 98+% 1708 ((1R)-ENDO)-(+)-3- 2283 (+)-MURAMIC ACID HYDRATE, BROMOCAMPHOR, 98% 98% 3516 ((1S)-(ENDO,ANTI))-(-)-3- 2966 (+)-N,N'- BROMOCAMPHOR-8- SULFONIC DIALLYLTARTARDIAMIDE, 99+% ACID, AMMONIUM SALT 2976 (+)-N-ACETYLMURAMIC ACID, 644 ((1S)-ENDO)-(-)-BORNEOL, 99% 97% 9587 (+)-11ALPHA-HYDROXY-17ALPHA- 965 (+)-NOE-LACTOL DIMER, 99+% METHYLTESTOSTERONE 5127 (+)-P-BROMOTETRAMISOLE 9590 (+)-11ALPHA- OXALATE, 99% HYDROXYPROGESTERONE, 95% 661 (+)-P-MENTH-1-EN-9-OL, 97%, 9588 (+)-17-METHYLTESTOSTERONE, MIXTURE OF ISOMERS 99% 730 (+)-PERSEITOL 8681 (+)-2'-DEOXYURIDINE, 99+% 7913 (+)-PILOCARPINE 7591 (+)-2,3-O-ISOPROPYLIDENE-2,3- HYDROCHLORIDE, 99% DIHYDROXY- 1,4- 5844 (+)-RUTIN HYDRATE, 95% BIS(DIPHENYLPHOSPHINO)BUT 9571 (+)-STIGMASTANOL
    [Show full text]
  • CPY Document
    3. eHEMieAL eOMPOSITION OF ALeOHOLie BEVERAGES, ADDITIVES AND eONTAMINANTS 3.1 General aspects Ethanol and water are the main components of most alcoholIc beverages, although in some very sweet liqueurs the sugar content can be higher than the ethanol content. Ethanol (CAS Reg. No. 64-17-5) is present in alcoholic beverages as a consequence of the fermentation of carbohydrates with yeast. It can also be manufactured from ethylene obtained from cracked petroleum hydrocarbons. The a1coholic beverage industry has generally agreed not to use synthetic ethanol manufactured from ethylene for the production of alcoholic beverages, due to the presence of impurities. ln order to determine whether synthetic ethanol has been used to fortify products, the low 14C content of synthetic ethanol, as compared to fermentation ethanol produced from carbohydrates, can be used as a marker in control analyses (McWeeny & Bates, 1980). Some physical and chemical characteristics of anhydrous ethanol are as follows (Windholz, 1983): Description: Clear, colourless liquid Boilng-point: 78.5°C M elting-point: -114.1 °C Density: d¡O 0.789 It is widely used in the laboratory and in industry as a solvent for resins, fats and oils. It also finds use in the manufacture of denatured a1cohol, in pharmaceuticals and cosmetics (lotions, perfumes), as a chemica1 intermediate and as a fuel, either alone or in mixtures with gasolIne. Beer, wine and spirits also contain volatile and nonvolatile flavour compounds. Although the term 'volatile compound' is rather diffuse, most of the compounds that occur in alcoholIc beverages can be grouped according to whether they are distiled with a1cohol and steam, or not.
    [Show full text]
  • Enhancing the Yields of Phenolic Compounds During Fermentation Using Saccharomyces Cerevisiae Strain 96581
    Food and Nutrition Sciences, 2014, 5, 2063-2070 Published Online November 2014 in SciRes. http://www.scirp.org/journal/fns http://dx.doi.org/10.4236/fns.2014.521218 Enhancing the Yields of Phenolic Compounds during Fermentation Using Saccharomyces cerevisiae Strain 96581 Adam A. Banach, Beng Guat Ooi* Department of Chemistry, Middle Tennessee State University, Murfreesboro, TN, USA Email: *[email protected] Received 2 September 2014; revised 28 September 2014; accepted 15 October 2014 Copyright © 2014 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/ Abstract Phenylethanol, tyrosol, and tryptophol are phenolic compounds or fusel alcohols formed via the Ehrlich pathway by yeast metabolism. These compounds can yield health benefits as well as con- tribute to the flavors and aromas of fermented food and beverages. This research shows that Sac- charomyces cerevisiae Strain 96581 is capable of producing significantly higher levels of these three compounds when the precursor amino acids were supplemented into either the Chardonnay concentrate for wine-making or the malt concentrate for brewing English Ale. Strain 96581 can produce phenylethanol, tyrosol, and tryptophol as high as 434 mg/kg, 365 mg/kg, and 129 mg/kg, respectively, in the beer fermentation. The performance of Ale yeast WLP002 from White Labs Inc. was also analyzed for comparison. Strain 96581 outperformed WLP002 in the control beer, the amino acids supplemented beer, and the kiwi-beer background. This shows that Strain 96581 is more effective than WLP002 in converting the malt and the kiwi fruit supplements via its endo- genous enzymes.
    [Show full text]
  • Price-List 2012-13
    Sanjay International Price-List 2012-13 Sanjay International Mr. Sanjay Mital +(91)-9810163421 No. 3439/5, Gali Bajrang Bali Chawri Bazar - Delhi, Delhi - 110 006, India http://www.indiamart.com/sanjayinternational/ Sanjay International Terms of Sale PRICES : Prices mentioned in the Price List are ruling at the time of printing of the Price List and subject to change without prior notice. Goods shall be invoice at prices ruling on the date of dispatch. TAXES & DUTIES : Sales Tax, MVAT, Octrio Duty, other Duties & Levies will be charged extra as applicable at the time of supply. For exemption of Sales Tax & Octrio Exemption Certificate should be sent along with order. PAYMENTS : Payments are to be made by Demand draft / cheques drawn on 'Sanjay international.' payable at Delhi. In the event of payment through bank the customer has to retire the documents immediately on presentation of the documents by the bank. The interest @21% will be charged on all the payments received after due dates. BULK REQUIREMENTS : Requirements/Enquiries for bulk packing and large quantities for any items will be considered. INSURANCE : Goods are packed with utmost care and forwarded at Customer's risk. No responsibility is taken for breakages or loss in transit. Goods can be insured at the customer's request at 1% of the invoice value. Charges for insurance will be made in the invoice itself. MINIMUM ORDER : All orders invoiced over Rs.25,000/- net shall be dispatched F.O.R. Delhi by transport, freight extra. Goods can be dispatched by Post, courier/angadia or by Passenger Train on customer's request freight will be born by customer.
    [Show full text]
  • A Catalytic Asymmetric Total Synthesis of (−)-Perophoramidine
    Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue A catalytic asymmetric total synthesis of (À)-perophoramidine† Cite this: Chem. Sci.,2015,6,349 B. M. Trost,* M. Osipov, S. Kruger¨ and Y. Zhang We report a catalytic asymmetric total synthesis of the ascidian natural product perophoramidine. The synthesis employs a molybdenum-catalyzed asymmetric allylic alkylation of an oxindole nucleophile and a monosubstituted allylic electrophile as a key asymmetric step. The enantioenriched oxindole product from this transformation contains vicinal quaternary and tertiary stereocenters, and is obtained in high yield along with high levels of regio-, diastereo-, and enantioselectivity. To install the second quaternary Received 19th June 2014 stereocenter in the target, the route utilizes a novel regio- and diastereoselective allylation of a cyclic Accepted 30th July 2014 imino ether to deliver an allylated imino ether product in near quantitative yield and with complete DOI: 10.1039/c4sc01826e regio- and diastereocontrol. Oxidative cleavage and reductive amination are used as final steps to access www.rsc.org/chemicalscience the natural product. Creative Commons Attribution-NonCommercial 3.0 Unported Licence. Introduction while that of the communesins is cis. From a biological perspective, perophoramidine (1) displays cytotoxicity against m In 2002, Ireland and coworkers reported the isolation and the HCT116 colon carcinoma cell line with an IC50 of 60 M. structural elucidation of a novel polycyclic alkaloid, (+)-per- The combination of its complex, densely functionalized struc- ophoramidine (1) from the Philippine ascidian organism Per- ture and cytotoxic properties make perophoramidine (1)an ophora namei (Fig. 1).1 The structure of (+)-perophoramidine (1) attractive target for asymmetric total synthesis.
    [Show full text]
  • Bioactive Metabolites of Bulbine Natalensis (Baker): Isolation, Characterization, and Antioxidant Properties
    Bioactive metabolites of Bulbine natalensis (Baker): Isolation, characterization, and antioxidant properties Olusola Bodede1,2, Nomfundo Mahlangeni2, Roshila Moodley2, Manimbulu Nlooto1, Elizabeth Ojewole1 1Discipline of Pharmaceutical Sciences, School of Health Sciences, University of KwaZulu-Natal, Durban, 4000, KwaZulu-Natal, South Africa, 2School of Chemistry and Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa Abstract Background: Medicinal plants continue to play a key role in disease management and modern drug development. ORIGINAL ARTICLE ORIGINAL Bulbine natalensis is one of several South Africa’s indigenous succulent medicinal species. B. natalensis’ high medicinal profile has made it a commercially-available herb within the South African market and beyond. However, there is a limited scientific report on its bioactive metabolites. Objectives: This study’s objective was to isolate and identify bioactive compounds from B. natalensis leaves and evaluate the compounds and crude extracts for antioxidant activity. Materials and Methods: Fractionation and purification of B. natalensis dichloromethane extract were done using chromatographic techniques. Whole extract profiling was carried out on dichloromethane and methanol extracts using gas chromatography-mass spectrometry (GC-MS). The isolated compounds and extracts were evaluated for antioxidant activity. Results: The dichloromethane extract yielded two pentacyclic triterpenes (glutinol and taraxerol), one tetracyclic triterpene
    [Show full text]
  • Nicolet Standard Collection of FT-IR Spectra
    Nicolet Standard Collection of FT-IR Spectra Library Listing – 3,119 spectra This collection is suited to the needs of analytical services and investigational laboratories. It provides a wide array of common chemicals in a lower cost package and can be used in combination with the Nicolet Standard Collection of FT-Raman Spectra to provide analysts a higher degree of confidence when identifying unknowns. The Nicolet Standard Collection of FT-IR Spectra includes 3,119 spectra of common chemicals with representatives of major functional groups and combinations of functional groups. It contains the same chemical series available in the Nicolet Standard Collection of FT-Raman Spectra. These matched libraries can be used alone or in combination with Thermo Fisher’s unique OMNIC Linked Search software. Nicolet Standard Collection of FT-IR Spectra Index Compound Name Index Compound Name 1177 (+)-1,4-Androstadiene-3,17-dione 1498 (+/-)-Ketamine .HCl; 2-(2- 140 (+)-11a-Hydroxyprogesterone, 95% Chlorophenyl)-2- 1221 (+)-2'-Deoxyuridine, 99+% (methylamino)cyclohex 2999 (+)-2,3-O-Benzylidene-D-threitol 1104 (+/-)-Octopamine .HCl, 98% 1291 (+)-2-Phenyl-1-propanol, 97% 2541 (+/-)-Pantothenol 933 (+)-3-Nitro-L-tyrosine, 99% 2058 (+/-)- 833 (+)-4-Cholesten-3-one Tetracyclo[6.6.2.0(2,7).0(9,14)]hexadec 739 (+)-6-Aminopenicillanic acid, 96% a-2,4,6,9,11,13-he 2361 (+)-Arabinogalactan 579 (+/-)-a-Benzoin oxime, 99% 2545 (+)-Boldine .HCl; 1,10- 2290 (+/-)-cis-2-Methylcyclohexanol, 97% Dimethoxyaporphine-2,9-diol .HCl 2287 (+/-)-trans-1,2-Dibromocyclohexane,
    [Show full text]
  • Nicolet Vapor Phase
    Nicolet Vapor Phase Library Listing – 8,654 spectra This library is one the most comprehensive collections of vapor phase FT-IR spectra. It is an invaluable tool for scientist involved in investigations on gas phase materials. The Nicolet Vapor Phase Library contains 8654 FT-IR spectra of compounds measured in gas phase. Most spectra were acquired by the Sigma-Aldrich Co. using product samples. Additional spectra were collected by Hannover University, University of Wurzburg and Thermo Fisher Scientific applications scientists. Spectra were collected using sampling techniques including heated or room temperature gas cell or a heated light-pipe connected to the outlet of a gas chromatograph. Nicolet Vapor Phase Index Compound Name Index Compound Name 8402 ((1- 5457 (-)-8-Phenylmenthol; (-)-(1R,2S,5R)-5- Ethoxycyclopropyl)oxy)trimethylsilane Methyl-2-(2-phenyl-2-propyl)cyc 4408 (+)-1,3-Diphenylbutane 1095 (-)-Carveol, mixture of isomers; p- 4861 (+)-1-Bromo-2,4-diphenylbutane Mentha-6,8-dien-2-ol 2406 (+)-3-(Heptafluorobutyryl)camphor 3628 (-)-Diisopropyl D-tartrate 2405 (+)-3-(Trifluoroacetyl)camphor 1427 (-)-Limonene oxide, cis + trans; (-)-1,2- 281 (+)-3R-Isolimonene, trans-; (1R,4R)- Epoxy-4-isopropenyl-1-methyl (+)-p-Mentha-2,8-diene 1084 (-)-Menthol; [1R-(1a,2b,5a)]-(-)-2- 289 (+)-Camphene; 2,2-Dimethyl-3- Isopropyl-5-methylcyclohexanol methylenebicyclo[2.2.1]heptane 2750 (-)-Menthoxyacetic acid 3627 (+)-Diisopropyl L-tartrate 1096 (-)-Myrtanol, cis-; (1S,2R)-6,6- 2398 (+)-Fenchone; (+)-1,3,3- Dimethylbicyclo[3.1.1]heptane-2-metha
    [Show full text]
  • Exploring and Engineering Yeasts for Industrial Application
    FOCUSED MEETING 2017 33rd International Specialised Symposium on Yeasts Exploring and Engineering Yeasts for Industrial Application 26 – 29 June 2017 University College Cork, Ireland http://microb.io/ISSY33 #ISSY33 POSTER ABSTRACT BOOK Contents: Session Poster number Page number Genomics and Hybrids P1 – P18 2 - 19 Interconnected Metabolic and Stress Networks P19 – P30 20 - 31 Strategies for Engineering Yeast Genomes P31 – P38 32 - 39 Tolerating the Stress of Industrial Processes P39 – P48 40 - 50 Exploiting Evolution to Develop Optimised Strains P49 – P57 51 - 59 Diverse Yeast Exploitation P58 – P92 60 - 94 Engineering Yeast Cell Factories 1 P93 – P103 95 - 105 Engineering Yeast Cell Factories 2 P104 – P113 106 – 115 Yeast biodiversity contributions to fermented beverages P114 – P148 116 - 150 1 | Abstracts are published as received from the authors and are not subject to editing Genomics and Hybrids P1 Saccharomyces Hybrids: Generation and Analysis Alexander Hinks Roberts1, Agnieszka Maslowska1, Thomas Davies1, Samina Naseeb3, Stuart Wilkinson2, Chris Powell2, Daniela Delneri3, Edward Louis1 1University of Leicester, Leicester, UK, 2University of Nottingham, Nottingham, UK, 3University of Manchester, Manchester, UK Saccharomyces interspecific hybrids, both artificial and natural, have significant potential in industry. This is because they can inherit and combine beneficial traits from each parental species. Breeding between species allows for mixing of the gene pool and under selective pressure, gives rise to individuals with beneficial gene combinations. However most hybrids are seen as evolutionary dead-ends. This is because they are usually sexually sterile, inhibiting the potential for strain improvement through breeding. The Saccharomyces sensu stricto clade consists of seven closely related species, many of which have been domesticated through use in various processes such as baking, biofuel production, wine making and brewing.
    [Show full text]
  • Generate Metabolic Map Poster
    Authors: J. Michael Cherry Eurie Hong Benjamin Vincent Cynthia Krieger An online version of this diagram is available at BioCyc.org. Biosynthetic pathways are positioned in the left of the cytoplasm, degradative pathways on the right, and reactions not assigned to any pathway are in the far right of the cytoplasm. Transporters and membrane proteins are shown on the membrane. Rama Balakrishnan Ron Caspi Periplasmic (where appropriate) and extracellular reactions and proteins may also be shown. Pathways are colored according to their cellular function. YeastCyc: Saccharomyces cerevisiae S288c Cellular Overview Connections between pathways are omitted for legibility.
    [Show full text]
  • Isolation and Identification of Indole-3-Ethanol (Tryptophol) from Cucumber Seedlings
    Plaint Physiol. (1967) 42, 520-524 Isolation and Identification of Indole.3-Ethanol (Tryptophol) from Cucumber Seedlings1'2 David L. Rayle3 and William K. Purves Department of Biological Sciences, University of California, Santa Barbara, California 93106 Received January 30, 1967. Summinary. Crulde ether extracts of green shoots of Culciumiis sativtus L. promoted the elongation of cucumber hypocotyl segments. Puirification of the extract was accomplished by DEAE cellulose, silicic acid, and magnesium silicate chromatography followed by gel filtration and preparative thin layer chromatography. Idelntification of the growth promoter as indole-3-ethanol was achieved bynmass spectrometry, thin layer and gas chromatography, ain( ultraviolet andl visil)le spectroscopy, as wvell as ly physiological characteristics. The cenitral role of indolic compounIds as plant ctiltnlre meldia containing trvptophan or tryptamine grnowth reguilators is well established. However, (2). Perlex and( Stowe observed lEt production few growth-promoting indolic compotin(ds have been from tryptophan by 1acilli s cerciis and( by Taphrina isolated in puire form from plaint tissute. The most deforimans (15, 16). \Wightman has reported some extenisively sttidied is indole-3-acetic acid (TAA), evideince for the occuirrence of lEt iII toIllato seed- which has been isolate(d in crystalline form from lings after the applicatioii of tryptophaii or indole- sev-eral sources (5, 10, 20). Toines et al. have iso- 3-lactic acid throtigh the cut stenms (23). In this lated pure indoleacetonitrile from immattire cabbage system it wvas postulatedl that iindolelactic acid was heads (8). Indoleacetaldehy-lde has been i(lentified decarboxvlated to lF,t which was theni oxidized to in plant tissue by Larsen (11).
    [Show full text]
  • Download Product Insert (PDF)
    Product Information 5-hydroxy Tryptophol Item No. 16114 CAS Registry No.: 154-02-9 Formal Name: 5-hydroxy-1H-indole-3-ethanol H Synonym: NSC 84416 N MF: C10H11NO2 FW: 177.2 Purity: ≥98% OH Stability: ≥2 years at -20°C HO Supplied as: A crystalline solid λ UV/Vis.: max: 225, 279 nm Laboratory Procedures For long term storage, we suggest that 5-hydroxy tryptophol be stored as supplied at -20°C. It should be stable for at least two years. 5-hydroxy Tryptophol is supplied as a crystalline solid. A stock solution may be made by dissolving the 5-hydroxy tryptophol in the solvent of choice. 5-hydroxy Tryptophol is soluble in organic solvents such as ethanol, DMSO, and dimethyl formamide, which should be purged with an inert gas. The solubility of 5-hydroxy tryptophol in these solvents is approximately 30 mg/ml. Further dilutions of the stock solution into aqueous buffers or isotonic saline should be made prior to performing biological experiments. Ensure that the residual amount of organic solvent is insignificant, since organic solvents may have physiological effects at low concentrations. Organic solvent-free aqueous solutions of 5-hydroxy tryptophol can be prepared by directly dissolving the crystalline solid in aqueous buffers. The solubility of 5-hydroxy tryptophol in PBS, pH 7.2, is approximately 0.3 mg/ml. We do not recommend storing the aqueous solution for more than one day. 5-hydroxy Tryptophol is a metabolite of tryptophan that is formed by the alcohol dehydrogenase-catalyzed reduction of the serotonin (Item No. 14332) intermediate, 5-hydroxyindoleacetaldehyde.1-3 Depending on the tissue NAD/NADH ratio, the acetaldehyde intermediate can also be oxidized by aldehyde dehydrogenase to form 5-hydroxyindoleacetic acid.2,4-5 Thus, a ratio of 5-hydroxy tryptophol to 5-hydroxyindoleacetic acid has been used as a biomarker for recent alcohol consumption.4-5 References 1.
    [Show full text]