22592-73-0Relevant academic research and scientific papers
Stereoselective synthesis of α-substituted ulosonic acids by magnesio-Reformatsky reactions
Csuk, Rene,Schroeder, Christina,Krieger, Claus
, p. 12947 - 12960 (1997)
A new method of homologation of aldonolactones allowing the incorporation of propionate units with excellent chemo- and stereoselectivity is performed by the magnesium-graphite mediated reaction between Oppolzer sultam derived α-halogenated amides and an aldonolactone.
Synthesis of β-hydroxy-δ-trichloromethyl-δ-valerolactones by intramolecular samarium/ytterbium diiodide-mediated Reformatsky reaction
Schulze, Thies M.,Grunenberg, J?rg,Schulz, Stefan
, p. 921 - 924 (2013)
The synthesis of α-methyl-β-hydroxy-δ-trichloromethyl- δ-valerolactone was achieved by an intramolecular Reformatsky reaction. The cyclisation was effected by samarium diiodide or (for the first time) ytterbium diiodide. The diastereoselectivity of the reaction corresponds to earlier investigations by Molander. Consecutive stereoselective reactions during the esterification to the Reformatsky precursor 1,1,1-trichloropent-4-en-2-yl 2-bromopropanoate and in the Reformatsky reaction itself led to (3RS,4RS,6SR)-4-hydroxy-3-methyl-6-(trichloromethyl)tetrahydro-2H-pyran-2-one (3a) as the major formed diastereomer. The influence of the orientation of the substituents in the transition state is discussed.
Method for manufacturing isavuconazole or ravuconazole
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Paragraph 0072; 0073, (2017/08/27)
The invention provides a method for manufacturing a triazole compound isavuconazole or ravuconazole which is enriched by a diastereoisomer and enantiomer. The method comprises the following steps: a Reformatsky reaction is carried out between ketone and dihalogeno metal propionitrile; an enantiomer mixture is generated, and separation is carried out. The method can obviously reduce steps for synthesis of isavuconazole or ravuconazole, yield of products is improved, and production cost is reduced.
Asymmetric synthesis of 4,1-Benzoxazepine-2,5-Diones -Effect of the halogen of (2S)-A-Haloacids
Rubab, Syeda Laila,Nisar, Bushra,Raza, Abdul Rauf,Ullah, Nisar,Tahir, Muhammad Nawaz
, p. 139 - 148 (2014/02/14)
Novel chiral 4,1-benzoxazepine-2,5-diones have been unusually synthesized in a single step by exploiting the chiral pool methodology. Substituted anthranilic acids afford N-Acylanthranilic acids and (3R)-3-Alkyl-4,1- benzoxazepines-2,5-dione upon coupling with a-chloroacids or a-bromoacids, respectively.
Synthesis of enantiomerically enriched-bromonitriles from amino acids
Tka, Najeh,Kraem, Jamil,Hassine, Bechir Ben
, p. 735 - 743 (2013/01/15)
Two methods were investigated for the preparation of six chiral-bromonitriles with different optic purities. The nitrous deamination of amino acids gives-bromoacids, which react with chlorosulfonyl isocyanate followed by triethylamine to afford-bromonitriles with moderate enantiomeric excess. However, the dehydration of corresponding-bromoamids using thionyl chloride gives-bromonitriles with good enantiomeric excess up to 94%. The use of phosphoryl chloride instead of thionyl chloride results in more than 30% racemization as determined by high-performance liquid chromatograpic analysis.
HETEROCYCLYLAMINES AS PI3K INHIBITORS
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Paragraph 1063, (2013/03/26)
The present invention provides heterocyclylamine derivatives of Formula I: wherein the variables are defined herein, that modulate the activity of phosphoinositide 3-kinases (PI3Ks) and are useful in the treatment of diseases related to the activity of PI3Ks including, for example, inflammatory disorders, immune-based disorders, cancer, and other diseases.
Synthesis, enantioresolution, and activity profile of chiral 6-methyl-2,4-disubstituted pyridazin-3(2H)-ones as potent N-formyl peptide receptor agonists
Cilibrizzi, Agostino,Schepetkin, Igor A.,Bartolucci, Gianluca,Crocetti, Letizia,Dal Piaz, Vittorio,Giovannoni, Maria Paola,Graziano, Alessia,Kirpotina, Liliya N.,Quinn, Mark T.,Vergelli, Claudia
experimental part, p. 3781 - 3792 (2012/08/28)
A series of chiral pyridazin-3(2H)-ones was synthesized, separated as pure enantiomers, and evaluated for N-formyl peptide receptor (FPR) agonist activity. Characterization of the purified enantiomers using combined chiral HPLC and chiroptical studies (circular dichroism, allowed unambiguous assignment of the absolute configuration for each pair of enantiomers). Evaluation of the ability of racemic mixtures and purified enantiomers to stimulate intracellular Ca 2+ flux in FPR-transfected HL-60 cells and human neutrophils and to induce β-arrestin recruitment in FPR-transfected CHO-K1 cells showed that many enantiomers were potent agonists, inducing responses in the sub-micromolar to nanomolar range. Furthermore, FPRs exhibited enantiomer selectivity, generally preferring the R-(-)-forms over the S-(+)-enantiomers. Finally, we found that elongation of the carbon chain in the chiral center of the active compounds generally increased biological activity. Thus, these studies provide important new information regarding molecular features involved in FPR ligand preference and report the identification of a novel series of FPR agonists.
Enantio-and diastereoselective oxidation of N-alkylimines using chiral-bromonitriles and hydrogen peroxide system
Tka, Najeh,Kraem, Jamil,Hassine, Bechir Ben
experimental part, p. 2994 - 3003 (2012/08/07)
Chiral-bromonitriles were prepared with good chemical and optical yields starting from natural-amino acids by dehydrating the corresponding α-bromoamides with thionyl chloride. The combined system-bromonitriles/ hydrogen peroxide was examined for the enantio-and diastereoselective oxidation of N-alkylimines in basic media at room temperature. The oxidation of N-tertiobutylarylimines leads to optically active oxaziridines with moderate enantiomeric excess. However, the oxidation of (S)-1-phenylethylarylimines affords the corresponding oxaziridines with good diasteromeric excess up to 97/3 as proved by gaseous-phase chromatography.
Study of the lanthanide-catalyzed, aqueous, asymmetric Mukaiyama aldol reaction
Mei, Yujiang,Averill, Derek J.,Allen, Matthew J.
scheme or table, p. 5624 - 5632 (2012/09/05)
The development of efficient methods for the asymmetric Mukaiyama aldol reaction in aqueous solution has received great attention. We have developed a new series of chiral lanthanide-containing complexes that produce Mukaiyama aldol products with outstanding enantioselectivities. In this paper, we describe an optimized ligand synthesis, trends in stereoselectivity that result from changing lanthanide ions, and an exploration of substrate scope that includes aromatic and aliphatic aldehydes and silyl enol ethers derived from aromatic and aliphatic ketones.
A new class of ligands for aqueous, lanthanide-catalyzed, enantioselective Mukaiyama aldol reactions
Mei, Yujiang,Dissanayake, Prabani,Allen, Matthew J.
supporting information; experimental part, p. 12871 - 12873 (2010/11/16)
The development of aqueous methods for generating enantiopure β-hydroxy carbonyl compounds is an important goal because these subunits compose many bioactive compounds and the ability to synthesize these groups in water has environmental and cost benefits. In this communication, we report a new class of ligands for aqueous, lanthanide-catalyzed, asymmetric Mukaiyama aldol reactions for the synthesis of chiral β-hydroxy ketones. Furthermore, we have used luminescence-decay measurements to unveil mechanistic information regarding the catalytic reaction via changes in water-coordination number. The precatalysts presented here yielded β-hydroxy carbonyls from aliphatic and aryl substrates with outstanding syn:anti ratios and enantiometric excesses of up to 49:1 and 97%, respectively.
