Abstract:
:(R)-(+) and (S)-(-)-1-phenylethylamine have been shown to promote highly diastereoselective and complementary enantioselective formal [3 + 2]carbocyclization reactions between 2,3-butanedione and conjugated nitroalkenes with formation of enantiomerically rich 2-hydroxy-3-nitrocyclopentanone derivatives. The reactions were carried out both in solvent and under solvent-free conditions. The absolute configurations of the products were assigned by X-ray and circular dichroism spectra analyses.
journal_name
Chiralityjournal_title
Chiralityauthors
Felluga F,Forzato C,Nitti P,Pitacco G,Prati F,Valentin E,Zangrando Edoi
10.1002/chir.22088subject
Has Abstractpub_date
2012-12-01 00:00:00pages
1005-12issue
12eissn
0899-0042issn
1520-636Xjournal_volume
24pub_type
杂志文章相关文献
CHIRALITY文献大全abstract::The enantioselective hydrogenation of C==N-C group containing compounds over modified metal catalysts is as yet an uninvestigated research area. This work contains results obtained on the hydrogenation of 1-pyrroline-2-carboxylate esters and sodium salt over cinchona alkaloid-modified alumina-supported Pd catalyst. Th...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.10001
更新日期:2001-01-01 00:00:00
abstract::The programmed assembly of p-octiphenyl rods carrying six complementary tripeptide strands was studied in the presence of bilayer membranes using circular dichroism (CD) spectroscopy. Thermal CD experiments demonstrated programmed assembly of anionic and cationic rods into supramolecules at low temperature that irreve...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20034
更新日期:2004-01-01 00:00:00
abstract::The modern use of preparative chromatography in pharmaceutical development is illustrated by the case of a recent preclinical candidate from these laboratories. The synthesis of the candidate employed a coupling of two enantiopure intermediates, each of which could be resolved using preparative chiral chromatography. ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20378
更新日期:2007-09-01 00:00:00
abstract::Chiral discrimination in a racemic mixture of dipalmitoylphosphatidylcholine (DPPC) is induced by a new selector at the water-air interface: L-DPPC is segregated in the condensed phase of a Langmuir monolayer upon interactions with an enantiopure amphiphilic compound. ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22508
更新日期:2015-11-01 00:00:00
abstract::In the presence of tridentate chiral ligand 4e, 99% e.e. value was obtained by asymmetric reduction of ethyl benzoylacetate with borane in toluene at 25 degrees C. Various ligands and reaction conditions were investigated to develop a reasonable mechanism that explains the experimental outcomes. ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20344
更新日期:2007-02-01 00:00:00
abstract::Trigonostemons G and H, two novel dimeric dinorditerpenoids, were isolated from the stem barks of Trigonostemon chinensis. Their planar structures and relative configurations were established by extensive analysis of spectroscopic data. Trigonostemons G and H possess a homodimeric biaryl skeleton obtained from two rea...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.23170
更新日期:2020-03-01 00:00:00
abstract::A new enantiomerically pure P-chiral phosphine, (S)-cyclohexylmethyl- (1-naphthyl)phosphine (1) was prepared by phosphine-borane methodology and used in a mechanistic study of the Mitsunobu reaction. Enantiomerically enriched (S)-cyclo- hexylmethyl(1-naphtyl)phosphine oxide (8) is obtained if the reaction proceeds thr...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/(SICI)1520-636X(2000)12:5/6<346::AID-CHIR8
更新日期:2000-06-01 00:00:00
abstract::Fourier transform infrared vibrational circular dichroism (FTIR-VCD) measurements have gone through major advances in the last decade. A major thrust in these advances was to find ways that can minimize the VCD spectral artifacts and obtain the VCD signals at enhanced signal quality. However, all these advances are no...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20999
更新日期:2011-10-01 00:00:00
abstract::Cyclodextrins that are indiscriminately carboxymethylated at the 2-, 3-, and 6-positions are used as chiral NMR solvating agents for cationic substrates with phenyl, naphthyl, pyridyl, indoline, and indole rings. Enantiodifferentiation with the alpha-, beta-, and gamma-cyclodextrin derivatives is compared. The carboxy...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20748
更新日期:2010-03-01 00:00:00
abstract::Searching the 3D structural fragments of organic molecules is challenging because of structural differences between X-ray and theoretically calculated geometries and the conformational flexibility of substituents. The codification program called Conformational Code for Organic Molecules (CCOM) can be used to unambiguo...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22596
更新日期:2016-05-01 00:00:00
abstract::A series of 1,4-disubstituted piperazine derivatives with hypnotic activity were examined on three polysaccharide-based chiral stationary phases, namely, Chiracel OD, Chiracel OJ and Chiralpak AD. It was possible to resolve all the compounds on all the phases examined (1.13 = alpha = 3.54). Cellulose tris(4-methyl...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/(SICI)1520-636X(1999)11:10<790::AID-CHIR9>
更新日期:1999-01-01 00:00:00
abstract::Enantioselective catalytic epoxidation of olefins is an important problem from both practical and mechanistic points of view. The origins of chiral induction by asymmetric porphyrin and salen complexes were investigated by FT-NMR T1 relaxation techniques. A new chiral vaulted porphyrin (1) that carries (S)-binaphthyl-...
journal_title:Chirality
pub_type: 杂志文章
doi:
更新日期:1998-01-01 00:00:00
abstract::Kynurenic acid (KYNA), an endogenous antagonist of N-methyl-D-aspartate and α(7) nicotinic acetylcholine receptors, is one of the L-tryptophan (Trp) metabolites. To compare the level of KYNA produced in the striatum of rats after independent administration of L-Trp and D-Trp, rats were intraperitoneally administered L...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20938
更新日期:2011-01-01 00:00:00
abstract::Both novel enantiopure trans-1-aminobenz[f]indan-2-ols (4) were obtained from the racemate by the diastereomeric salt formation with (+)- and (-)-dibenzoyltartaric acids (8), respectively, and the absolute configuration of the enantiomer 4 in the less-soluble diastereomeric salt of racemic 4 with (+)-8 was determined ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20101
更新日期:2005-02-01 00:00:00
abstract::The electronic circular dichroism (ECD) spectra of two sesquiterpenoids (1 and 2) related to oplopanone, obtained from a methanolic extract of the plant Serphidium stenocephalum (Artemisia stenocephala), were measured and reproduced by means of time-dependent density functional theory (TDDFT) calculations, establishin...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22263
更新日期:2014-01-01 00:00:00
abstract::The chiral squaramide catalysts (8-15) were synthesized, and their catalytic efficiency in the enantioselective conjugate addition of pyrazolones to nitroalkenes was described. This protocol provides excellent chemical yields (up to 93%) of chiral 5-methyl-4-(2-nitro-1-arylethyl)pyrazol-3-ol derivatives with high enan...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.23295
更新日期:2021-01-11 00:00:00
abstract::The application of helical poly[(S)-3-vinyl-2,2'-dihydroxy-1, 1'-binaphthyl] (L*) in the asymmetric borane reduction of prochiral ketones was studied. The results showed that L* had excellent catalytic activity as well as enantioselectivity, giving up to 96% yield and up to 99% enantiomeric excess (ee) of the correspo...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22459
更新日期:2015-07-01 00:00:00
abstract::The impact of crystalline forces on the solid-state circular dichroism (CD) spectrum of hypothemycin (), a biologically active molecule extracted from natural sources, has been analyzed by means of time-dependent density functional theory CD calculations. Input structures were extracted from the X-ray geometry of and ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22008
更新日期:2012-09-01 00:00:00
abstract::About 30% of a chemically diverse set of compounds were found to separate on four polysaccharide chiral stationary phases using polar organic mobile phases. No structural features appeared to correlate to successful separations. Titrations between normal and polar organic mobile phases suggested that separation mechan...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20212
更新日期:2006-01-01 00:00:00
abstract::Human carboxylesterase 1 (hCES1) is an enzyme that plays an important role in hydrolysis of pharmaceuticals in the human liver. In this study, elucidation of the chiral recognition ability of hCES1 was attempted using indomethacin esters in which various chiral alcohols were introduced. Indomethacin was condensed with...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.23141
更新日期:2020-01-01 00:00:00
abstract::A statement has been formulated that chirality is an indispensable inherent property of all material objects, at one level of organization of matter or another. The translation of chirality from one level of material objects to another deserves our attention. The parity violation of weak interactions can be discussed ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20271
更新日期:2006-08-01 00:00:00
abstract::The chiral recognition ability and solvent versatility of a new chiral stationary phase containing amylose 3,5-dimethylphenylcarabamate immobilized onto silica gel (CHIRALPAK IA) is investigated. Thus, the direct enantioselective separation of a set of racemic N-alkylated barbiturates and 3-alkylated analogs of thalid...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20398
更新日期:2007-06-01 00:00:00
abstract::The elusive epimerization process in the chiral butenolide moiety of Annonaceous acetogenins was examined under several sets of conditions commonly used for elimination leading to the alpha, beta-unsaturated lactone and the results provide practical guidance in choosing elimination conditions. ...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/(SICI)1520-636X(2000)12:3<127::AID-CHIR4>3
更新日期:2000-03-01 00:00:00
abstract::The R enantiomers of some of the 2-arylpropionic acid non-steroidal antiinflammatory drugs (NSAIDs) are known to undergo metabolic chiral inversion to their more pharmacologically active antipodes. This process is drug and species dependent and usually unidirectional. The S to R chiral inversion, on the other hand, is...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/(SICI)1520-636X(1997)9:1<29::AID-CHIR6>3.0
更新日期:1997-01-01 00:00:00
abstract::The aim of our study was to synthesize vinylic and pyrido-fused pyridazines with a spirano moiety and to investigate their stereochemistry by spectroscopic and HPLC analyses. The vinylic compounds 5 were obtained by Knoevenagel condensation of cyclohexylidene malonates 1 with pyridazinecarbaldehyde 2. Compound 5b exhi...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.10096
更新日期:2002-05-15 00:00:00
abstract::In this research, 10 chiral pesticides in fruits and vegetables were simultaneously determined using chiral liquid chromatography triple quadrupole-linear ion trap hybrid mass spectrometry (LC-QqLIT). The QuEChERS method was applied for sample preparation, and an enhanced product ion (EPI) scan was used to acquire tan...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22531
更新日期:2015-12-01 00:00:00
abstract::Benalaxyl (BX), methyl-N-phenylacetyl-N-2,6-xylyl alaninate, is a potent acylanilide fungicide and consist of a pair of enantiomers. The stereoselective metabolism of BX was investigated in rat and rabbit microsomes in vitro. The degradation kinetics and the enantiomer fraction (EF) were determined using normal high-p...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.20879
更新日期:2011-02-01 00:00:00
abstract::Isophthalic and terephthalic acid monoesters of cyclic nigerosyl-(1→6)-nigerose (CNN), a cyclic tetrasaccharide composed of four d-glucopyranosyl residues connected by alternating α-1,3- and α-1,6-linkages, were synthesized as novel chiral supramolecular sensitizers for enantiodifferentiating photoisomerization of (Z)...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22014
更新日期:2012-11-01 00:00:00
abstract::Previously, a diazaphospholidine has been synthesized and evaluated as a chiral derivatizing reagent for the determination of the optical purity of chiral alcohols via 31P NMR spectroscopy (Alexakis et al., J. Org. Chem. 57:1224-1237, 1992). Our laboratory is interested in the advantageous and practical applications o...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.530060306
更新日期:1994-01-01 00:00:00
abstract::Supercritical fluid chromatography (SFC) is already used for enantioseparation in the pharmaceutical industry, but it is rarely used for the separation of chiral pesticides. Comparing with high performence liquid chromatography, SFC uses much more environmnetal friendly and economic mobile phase, supercritical CO2 . I...
journal_title:Chirality
pub_type: 杂志文章
doi:10.1002/chir.22836
更新日期:2018-05-01 00:00:00