72922-83-9Relevant academic research and scientific papers
New chiral aminoamidoximes: Syntheses and investigation of heterocyclic compounds
Tka, Najeh,Hassine, Bechir Ben
, p. 828 - 835 (2012/02/03)
New chiral aminoamidoximes were prepared from (L)-proline, (L)-alanine, and (L)-isoleucine by treatment of the corresponding aminonitriles with hydroxylamine in the presence of triethylamine. The intramolecular cyclization with α-bromoacid chlorides and aldehydes was investigated to give new 1,2,4-oxadiazin-6-ones and 1,2,4-oxadiazoles, respectively. These compounds were likely to undergo an intermolecular cyclization through oxygen and nitrogen. However, intramolecular cyclization through two nitrogens did not occur even after changing reaction conditions. Taylor & Francis Group, LLC.
Ligand creation via linking - A rapid and convenient method for construction of novel supported PyOX-ligands
Oila, Markku J.,Tois, Jan E.,Koskinen, Ari M.P.
, p. 10748 - 10756 (2007/10/03)
A novel supported amino alcohol linker was synthesized and utilized for attachment of picolinic acid derivatives onto different supports. When the resin bound molecule was further activated, the PyOX-moiety could be constructed reliably in enantiopure form. Furthermore, an efficient Pd-catalyzed modification of a picolinic acid derivative is presented.
Unified route to the palmarumycin and preussomerin natural products. Enantioselective synthesis of (-)-preussomerin G
Barrett, Anthony G.M.,Blaney, Frank,Campbell, Andrew D.,Hamprecht, Dieter,Meyer, Thorsten,White, Andrew J.P.,Witty, David,Williams, David J.
, p. 2735 - 2750 (2007/10/03)
The total syntheses of eight members of the palmarumycin family have been achieved, with identification of the absolute stereochemistry for three of these natural products. In addition, the ras-farnesyl transferase inhibitor (-)-preussomerin G has been synthesized, achieving the first enantioselective route for accessing this family of natural products. Highlights of the synthetic work include an asymmetric epoxidation of a cyclic enone in excellent yield and enantiomeric excess and a potentially biomimetic oxidative spirocyclization for the introduction of the bis-spiroketal array unique to the preussomerin natural products.
Preparation of both enantiomers of 1-allyl-1,2,3,4-tetrahydro-β-carboline using allyltin reagents and a chiral auxiliary derived from L-proline
Itoh, Takashi,Matsuya, Y?ji,Enomoto, Yasuko,Ohsawa, Akio
, p. 7277 - 7289 (2007/10/03)
β-Carboline, which had an acyl group derived from L-proline at the 9-position, reacted with allyltributyltin and 2,2,2-trichloroethyl chloroformate to afford an 1-allyl-1,2-dihydro-β-carboline derivative in a diastereoselective manner. The chiral acyl group at N-9 was readily eliminated by aqueous alkali to give a corresponding carboxylic acid. The formed 1-allyl-1,2-dihydro-β-carboline was transformed via two reduction steps to 1-allyl-1,2,3,4-tetrahydro-β-carboline in high ee. When the allylation was carried out using tetraallyltin instead of allyltributyltin, the stereoselectivity was reversed, and the antipode of the allyl adduct was obtained in high yield and ee in the presence of tin(IV) tetraiodide. Thus, it was found that both enantiomers of 1-allyl-β-carboline were obtained in good enantioselectivities by the use of the same chiral auxiliary.
alpha -AMINO ACIDS AS CHIRAL EDUCTS FOR ASYMMETRIC PRODUCTS. A GENERAL SYNTHESIS OF D- alpha -AMINO ACIDS FROM L-SERINE.
Maurer,Takahata,Rapoport
, p. 1095 - 1098 (2007/10/02)
A short and chirally efficient synthesis of four D- alpha -amino acids is described with L-serine as the chiral educt. The key C-C bond-forming reactions are the aminoacylations of organometallics with the lithium salt of N-(phenylsulfonyl)-L-serine (2) to give optically pure N-blocked alpha -amino ketones. Reduction of the carbonyl group to carbinol or methylene followed by oxidation of the hydroxymethyl to carboxyl gives the N-blocked D-amino acids. The examples investigated (norleucine, alpha -aminopimelic acid, DOPA, and allothreonine) demonstrate the broad applicability of the method.
Synthesis and Liquid Chromatographic Evalution of Some Chiral Derivatizing Agents for Resolution of Amine Enantiomers
Clark, C. Randall,Berksdale, Jeffrey M.
, p. 958 - 962 (2007/10/02)
A series of 1-prolyl chlorides were synthesized and evaluated as chiral derivatizing agents for the liquid chromatographic analysis of enantiomeric amines.The diastereomeric 1-prolinamides showed st
