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Pure Appl. Chem., Vol. 73, No. 2, pp. 255–259, 2001. © 2001 IUPAC 255 Racemic catalysis through asymmetric activation* Koichi Mikami†, Toshinobu Korenaga, Yousuke Matsumoto, Makoto Ueki, Masahiro Terada, and Satoru Matsukawa‡ Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8552, Japan Abstract: “Asymmetric activation” provides a general strategy for the use of racemic catalysts not only with atropos but also tropos ligands without enantiomer resolution. Asymmetric catalysis of organic reactions by metal complexes bearing chiral ligands is an impor- tant

Note 879 The First Total Synthesis of Racemic Hydroxymoloka’iamine Nisar Ullah Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia Reprint requests to Professor Nisar Ullah. Fax: + 966 3 860 4277. E-mail: nullah@kfupm.edu.sa Z. Naturforsch. 2009, 64b, 879 – 882; received April 4, 2009 The first total synthesis of racemic hydroxymoloka’iam- ine, a new brominated metabolite isolated from Red Sea sponge Pseudoceratna arabica, was achieved in a high-yield reaction sequence. Key words: Total Synthesis, Natural Product

A Short and Productive Synthesis of Racemic a-Lipoic Acid Friedhelm Balkenhohl, Joachim Paust* Main Laboratory of BASF AG, D-67056 Ludwigshafen, Germany Z. Naturforsch. 54b, 649-654 (1999); received December 4, 1999 Lipoic Acid, Radical Induced C-C-Bond Formation, Baeyer-Villiger Oxidation, Ether Cleavage, Isothiuronium Salts Racemic a-lipoic acid is synthesized in four steps from the base chemicals vinyl ethyl ether and cyclohexanone. The total yield is 40%. Results and Discussion Biochemistry a-Lipoic acid is involved in central biochemical processes as a

How Different are the Crystal Structures of Chiral and Racemic Diacylphosphatidylethanolamines? Douglas L. Dorset Electron Diffraction Department, Medical Foundation of Buffalo, Inc., 73 High Street, Buffalo, New York 14203, U .S .A . Z. Naturforsch. 43c, 319-327 (1988); received November 20, 1987 Phospholipids, X-Ray Diffraction, Electron Diffraction Both chiral and racemic phosphatidylethanolamines are known to crystallize in a similar poly- morphic form with nearly the same lamellar spacing; yet published lamellar X-ray diffraction intensity data for

Zeitschrift fur Kristallographie 160, 39-44 (1982) © by Akademische Verlagsgesellschaft 1982 Molecular and crystal structure of racemic phosphinothricin hydrate (3-ammonio- 3-carboxy-propyl)methylphosphinate-hydrate E. F. Paulus and S. Grabley Hoechst AG, D-6230 Frankfurt/Main 80, Federal Republic of Germany Dedicated to Professor Klaus Weissermel on the occasion ofhis 60th birthday Received: November 3, 1981 Racemic phosphinothricin hydrate / 3-ammonio-3-carboxy-propyl-methylphosphinate-hydrate / X-ray structure analysis Abstract. Racemic phosphinothricin

American Mineralogist, Volume 94, pages 1556–1559, 2009 0003-004X/09/1112–1556$05.00/DOI: 10.2138/am.2009.3089 1556 A statistical reassessment of the evidence for the racemic distribution of quartz enantiomorphs María TáMara and MarTin r. PresTon* Department of Earth and Ocean Sciences, University of Liverpool, 4 Brownlow Street, Liverpool L69 3GP, U.K. absTracT A statistically based re-evaluation of the evidence for a racemic abundance of quartz enantiomers suggests that, while this hypothesis is valid at the global scale, local deviations occur such that

Optical Resolution of Racemic Jasmonic Acid by Separation of Diastereomeric Mandelyl Esters Robert Kramell*, Gernot Schneider, Jürgen Schmidt, Günther Sembdner, and Klaus Schreiber In stitu te o f P lant B iochem istry, A cadem y of Sciences of the G D R , W einberg 3, D D R -4050 H alle (Saale), G erm an D em ocratic R epublic Z. N a tu rfo rsc h . 45b, 3 7 7 -3 8 1 (1990); received A u g u st 17, 1989 3-O xo-2-(2Z -pentenyl)-cyclopentane-l-acetic A cid, Jasm onic A cid , O ptical R eso lu tion , M andelic A cid , Plant G row th R egulator T he reaction

On racemic and L-malates: a comparison of their crystal structures Michel Fleck*, I, Ekkehart TillmannsI, Ladislav Bohatý II and Peter HeldII I Institut für Mineralogie und Kristallographie, Universität Wien, Althanstr. 14, A-1090 Wien, Austria II Institut für Kristallographie, Universität zu Köln, Zülpicher Str. 49b, D-50674 Köln, Germany Received March 7, 2003; accepted November 12, 2003 Racemic malates / L-malates / Single crystal structure analysis / X-ray diffraction Abstract. The crystal structures of eight different L-ma- lates have been determined

membrane technology for the separation of racemic mixtures. Journal of Membrane Science, 113, 351–360. DOI: 10.1016/0376-7388(95)00176-x. http://dx.doi.org/10.1016/0376-7388(95)00176-X [13] Li, D. C., Cheng, S. W., Wei, D. Z., Ren, Y. H.,& Zhang, D. R. (2007a). Production of enantiomerically pure (S)-β-phenylalanine and (R)-β-phenylalanine by penicillin G acylase from Escherichia coli in aqueous medium. Biotechnology Letters, 29, 1825–1830. DOI: 10.1007/s10529-007-9480-9. http://dx.doi.org/10.1007/s10529-007-9480-9 [14] Li, M. S., Zhao, Y. J., Zhao, S. Y., Xing W. H

AN IMPROVED 1 9F NMR RACEMIZATION TEST M.Baumeister, K.Seeholzer, i.Ugi (Speaker), B.Westinger Organisch-Chemisches Institut der Technischen Universität München, D-8046 Garching W.E.HUll Bruker Analytische Meßtechnik GmbH 7512 Rheinstetten 4-Fo. Present adress: Institut für Biochemie DKFZ, 6900 Heidelberg Since the customary racemization tests are based on the chemical degration of peptides (l),the derivatization of oC- amino acids, and the separation of enantiomers (2) and diaste- reomers (3), such tests are relatively time-consuming. A fast and