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Francisco Sánchez-Izquierdo et al.
Organic letters, 9(9), 1769-1772 (2007-04-03)
[structure: see text] The total synthesis of the putative structure of the Stemona alkaloid stemonidine has been completed. The key transformations include a 1,3-dipolar cycloaddition of a chiral nitrone derived from (S)-prolinol and a spirolactonization process involving the generation of
Janine Cossy
Chemical record (New York, N.Y.), 5(2), 70-80 (2005-04-13)
The synthesis of optically active substituted piperidines has been achieved by using four different methodologies. The first one is an intramolecular nucleophilic displacement of activated alcohol moieties that was used to build up the piperidine ring of (-)-prosophylline and (-)-slaframine
Magnus Rueping et al.
Organic & biomolecular chemistry, 10(30), 6201-6210 (2012-05-16)
A highly efficient route for the synthesis of valuable 3,4-substituted chromenone derivatives by the reaction of 1,3-diketones with aldehydes in the presence of l-proline was developed. The reactions take advantage of readily available starting materials and follow a Knoevenagel condensation/Michael
Ronald A Glabonjat et al.
Talanta, 222, 121677-121677 (2020-11-11)
Non-ribosomal peptides are one class of bacterial metabolites formed by gut microbiota. Intestinal resident Klebsiella oxytoca produces two pyrrolobenzodiazepines, tilivalline and tilimycin, via the same nonribosomal biosynthesis platform. These molecules cause human disease by genotoxic and tubulin inhibitory activities resulting
Václav Vanĕk et al.
Nucleic acids symposium series (2004), (52)(52), 537-538 (2008-09-09)
Commercially available trans-4-hydroxy-L-proline has been used as a starting material for the synthesis of prolinol-based nucleotide analogues with N-phosphonomethyl moiety attached to the nitrogen atom of prolinol ring. The synthetic methodology based on the inversion of configuration at both 1-
Qianli Chu et al.
Organic letters, 10(5), 749-752 (2008-02-14)
A fluorous prolinol precatalyst bearing only 34 fluorine atoms has been immobilized in the hydrofluoroether solvent HFE-7500. The CBS reduction of acetophenone proceeded rapidly, in high yield and in high ee in the absence of any organic solvent. The organic
Satnam Lidder et al.
Journal of medical toxicology : official journal of the American College of Medical Toxicology, 4(3), 167-169 (2008-09-30)
Many countries have specific legislation, such as the Controlled Substances Act (1970) in the United States and the Misuse of Drugs Act (1971) in the United Kingdom to control recreational drugs. There is a growing market and supply of "novel"
Anne Cochi et al.
Organic letters, 13(16), 4442-4445 (2011-07-29)
The activation of N-alkyl prolinols by XtalFluor E allowed the formation of an aziridinium intermediate that can react with tetrabutylammonium azide (nBu(4)NN(3)) to produce 3-azidopiperidines and/or 2-(azidomethyl)pyrrolidines, in a ratio up to 100/0. These 3-azidopiperidines can be reduced to the
Patrick Bolze et al.
Organic letters, 10(17), 3753-3756 (2008-07-29)
A simple organocatalytic approach to highly attractive chiral building blocks is presented. By the reaction of beta-ketoesters with alpha,beta-unsaturated aldehydes using a chiral TMS-protected prolinol as the catalyst, optically active 5-(trialkylsilyl)cyclohex-2-enones are formed in good yields and with 98-99% ee.
Hao Li et al.
Organic letters, 9(6), 965-968 (2007-02-15)
A conjugate addition-aldol-dehydration reaction of alpha,beta-unsaturated aldehydes with 2-N-protected amino benzaldehydes has been developed. The process is promoted by (S)-diphenylprolinol TES ether to afford synthetically useful 1,2-dihydroquinolines in high enantioselectivities with good yields. [reaction: see text]
Yuko Kawanami et al.
The Journal of organic chemistry, 74(20), 7908-7921 (2009-09-19)
The photochirogenesis of 2-anthracenecarboxylic acid (AC) complexed to a hydrogen-bonding template (TKS159) was investigated to obtain mechanistic information on how chirogenesis is achieved for the dimerization of AC. Complexation of AC to TKS159 leads to the shielding of one of
Naoto Kojima et al.
Organic & biomolecular chemistry, 9(12), 4425-4428 (2011-05-10)
The asymmetric alkynylation of aliphatic and aromatic aldehydes with propiolates was mediated by dialkylzinc and a novel prolinol catalyst without high reagent loading and any additives, such as Ti(Oi-Pr)(4), to give the corresponding γ-hydroxy-α,β-acetylenic esters with high enantiomeric excess of
Katsuhiko Moriyama et al.
The Journal of organic chemistry, 77(21), 9846-9851 (2012-10-12)
The intramolecular aminohydroxylation of N-alkenylsulfonamides proceeded under heavy metal-free conditions to give substituted prolinol derivatives in high yields. Oxone activated by catalytic Brønsted acid worked well as an electrophilic oxidant for this reaction.
Weixu Zhai et al.
Bioorganic & medicinal chemistry letters, 18(18), 5083-5086 (2008-08-30)
The discovery and optimization of a novel series of prolinol-derived GHSR agonists is described. This series emerged from a 11,520-member solid-phase library targeting the GPCR protein superfamily, and the rapid optimization of low micromolar hits into single-digit nanomolar leads can
Alessandra Lattanzi
Organic letters, 7(13), 2579-2582 (2005-06-17)
[reaction: see text] An operationally simple and mild protocol for the catalytic enantioselective epoxidation of alpha,beta-unsaturated ketones has been estabilished using commercially available alpha,alpha-diphenyl-l-prolinol as bifunctional organocatalyst and tert-butyl hydroperoxide (TBHP) as oxidant. The epoxides have been obtained in good
Gretta C M'bitsi-Ibouily et al.
Scientific reports, 9(1), 4146-4146 (2019-03-13)
Sulpiride (SPR) is a selective antagonist of central dopamine receptors but has limited clinical use due to its poor pharmacokinetics. The aim of this study was to investigate how metal ligation to SPR may improve its solubility, intestinal permeability and
Pei Juan Chua et al.
Bioorganic & medicinal chemistry letters, 19(14), 3915-3918 (2009-04-11)
Though many chiral amines such as l-proline and its derivatives have proven to be versatile catalysts in many reactions, L-prolinol was seldom used as organocatalyst for reactions. Herein, we report the first L-prolinol catalyzed asymmetric Michael addition of cyclohexanone to
Anna Maria Deobald et al.
Organic & biomolecular chemistry, 10(38), 7681-7684 (2012-08-25)
An eco-friendly synthesis of highly functionalized epoxides and their incorporation into an organocatalytic multicomponent approach are reported. For this, a modified class of diarylprolinol silyl ethers was designed to enable high catalytic activity in an environmentally benign solvent system. The
Patrick G McGarraugh et al.
Organic letters, 13(24), 6460-6463 (2011-11-17)
Products of a novel iminium-catalyzed oxa-Michael addition undergo a kinetic resolution by a subsequent enamine-catalyzed intermolecular reaction. This is a rare example of kinetic resolution by enamine catalysis and the first organocascade kinetic resolution. This resolution produces enantioenriched 2,6-cis-tetrahydropyrans and
Yanlong Chen et al.
Journal of chromatography. A, 1626, 461341-461341 (2020-08-17)
The recognition and separation of polar chiral compounds are important technological challenges in separation science. Taking full advantage of the intrinsically chiral environment and multiple interactions featured by macrocycles, we designed the first example of porous methylated cyclodextrins-containing polymers (MP-CDPs)
Simone Egetenmeyer et al.
Current protocols in nucleic acid chemistry, Chapter 4, Unit4-Unit4 (2012-12-21)
Protocols for the synthesis of oligodeoxynucleotides with a short peptidyl substituent linked to the 5'-O-terminus through a phosphodiester bond are presented. The example given is a peptidyl cap consisting of the residues of L-prolinol, glycine, and the acyl residue of
Takashi Mino et al.
The Journal of organic chemistry, 70(5), 1937-1940 (2005-02-26)
Chiral diaminophosphines 4 were prepared from (S)-prolinol-derived aminophosphine oxide 5 by bromination with ring expansion followed by amination with ring contraction and reduction, using trichlorosilane. In the presence of 4 as a ligand, palladium-catalyzed asymmetric allylic alkylation of 1,3-diphenyl-2-propenyl acetate
Johnathan E Holladay et al.
Applied biochemistry and biotechnology, 113-116, 857-869 (2004-04-01)
Technology to convert biomass into chemical building blocks provides an opportunity to displace fossil fuels and increase the economic viability of biorefineries. Coupling fermentation capability with aqueous-phase catalysis provides novel routes to monomers and chemicals, including those not accessible from
Tatsuya Urushima et al.
Organic letters, 12(13), 2966-2969 (2010-06-10)
Diarylprolinol was found to be an effective organocatalyst of the direct, enantioselective aldol reaction of commercially available polymeric ethyl glyoxylate, affording gamma-ethoxycarbonyl-beta-hydroxy aldehydes, versatile synthetic intermediates, in good yield with excellent enantioselectivity.
Zoltán Dalicsek et al.
Organic letters, 7(15), 3243-3246 (2005-07-16)
[reaction: see text]. An operationally simple and recoverable fluorous CBS methodology was developed. The in situ-generated fluorous oxazaborolidine efficiently catalyzed the reduction of ketones with high enantioselectivity and reactivity. The subsequent recycling of the fluorous prolinol precatalyst was achieved by
Yawen Li et al.
The Journal of organic chemistry, 72(1), 288-291 (2006-12-30)
To seek novel metal-free organic catalysts for epoxidation with high stereoselectivity, a series of 4-substituted-alpha,alpha-diaryl-prolinols were synthesized in four steps from trans-4-hydroxyl-L-proline. These prolinol derivatives catalyzed the asymmetric epoxidation of alpha,beta-enones to give the corresponding chiral epoxides in good yields
Ina Mager et al.
Organic letters, 12(7), 1480-1483 (2010-03-06)
A highly efficient approach for the synthesis, application, and recycling of immobilized diarylprolinol silyl ethers was developed. The MeOPEG-supported Jørgensen-Hayashi catalyst provides unchanged reactivity and selectivity as compared to the homogeneous catalyst, as demonstrated for the Michael addition of nitromethane
Iris Thondorf et al.
Bioorganic & medicinal chemistry, 19(21), 6409-6418 (2011-10-01)
The proton-coupled amino acid transporter hPAT1 has recently gained much interest due to its ability to transport small drugs thereby allowing their oral administration. A three-dimensional quantitative structure-activity relationship (3D QSAR) study has been performed on its natural and synthetic
Chuan Wang et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 18(37), 11531-11535 (2012-07-28)
Sulfenylated oxindoles: The first asymmetric sulfenylation of N-Boc-protected oxindoles has been developed to provide products containing a tetrasubstituted stereogenic center in high to excellent yields (86-98 %) and, in most cases, excellent enantioselectivities (up to 96 % ee; see scheme).
J M Carboni et al.
Oncogene, 10(10), 1905-1913 (1995-05-18)
Recent results from several laboratories including ours strongly suggest that farnesyltransferase (FT) inhibitors belonging to distinct chemical classes block growth of oncogenic Ras transformed cells at concentrations that do not affect the growth and viability of normal cells. This is
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