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1.
Biomed Microdevices ; 18(6): 110, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27834053

RESUMO

Early liver cancer diagnosis has clinical significance in treating cancer. Joint detection of multiple biomarkers has been considered as an effective and reliable method for early cancer diagnosis. In this work, a novel biosensor based on microcantilever array was batch-fabricated for multiple liver cancer biomarkers detection with high sensitivity, high accuracy, high throughput, and high specification. A micro-cavity was designed in the free end of the cantilever for local reaction between antibody and antigen, which can dramatically reduce the effect of adsorption-induced stiffness coefficient k variation. Furthermore,the pillar arrays in the micro-cavity were designed for increasing detection upper limit. A linear relationship between the relative frequency shift and the antigen concentration was observed for three liver cancer biomarkers, alpha-fetoprotein (AFP), γ-glutamyltranspeptidase II (GGT-2), and hepatocyte growth factor (HGF). Slight cross-reaction response to different antigens ensures high specificity of the sensor. These features will promote clinical application of the cantilever sensors in early cancer diagnosis.


Assuntos
Detecção Precoce de Câncer/instrumentação , Neoplasias Hepáticas/diagnóstico , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/metabolismo , Reações Cruzadas , Humanos , Neoplasias Hepáticas/sangue , Microtecnologia , Sensibilidade e Especificidade
2.
Org Lett ; 18(8): 1760-3, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27080342

RESUMO

An organocatalytic enantioselective reaction of 2-methylcyclopentane-1,3-dione, nitroalkene, and α,ß-unsaturated aldehyde with the diphenylprolinol catalyst was developed to give the highly functionalized Hajos-Parrish-type ketones with five to six contiguous stereocenters and two quaternary carbon stereogenic centers with high diastereoselectivity and enantioselectivity. The structures of the adducts were unambiguously confirmed by single-crystal X-ray crystallographic analyses of the appropriate products.

3.
Org Lett ; 15(3): 468-71, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23311855

RESUMO

An expedited method was developed for the enantioselective synthesis of dodecahydrobenz[a]indolo[3,2-h]quinolizine containing five contiguous stereogenic centers with high enantioselectivities (>99% ee). The methodology comprises a domino organocatalytic double Michael reaction and Pictet-Spengler-lactamization reaction. The structures and absolute configurations of the appropriate products were confirmed by X-ray analysis.


Assuntos
Quinolizinas/síntese química , Catálise , Cristalografia por Raios X , Ciclização , Alcaloides Indólicos/síntese química , Alcaloides Indólicos/química , Modelos Moleculares , Estrutura Molecular , Quinolizinas/química , Estereoisomerismo
4.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): m1234, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125571

RESUMO

The title compound, (C(2)H(8)N)(4)[Cu(C(6)H(2)N(10))(2)Cl(2)], consists of an anionic complex which is composed of a Cu(II) ion surrounded by four N atoms from two pyrazine-2,3-diylbis(1H-tetra-zol-1-ide) ligands, and two Cl(-) atoms in a trans-Cl(2)N(4) coordination geometry; the Cu(II) atom lies on a site of symmetry 2/m. The Cu-Cl distance of 2.8719 (5) Šis long due to the Jahn-Teller distortion of the d(9) electron configuration of Cu(II) ion. The tetra-zole and pyrazine rings make an N-C-C-N torsion angle of 38.25 (17)°. The charge of the anionic complex is balanced by four dimethyl-ammonium cations, which inter-act with the anionic complexes via N-H⋯N and N-H⋯Cl hydrogen bonds.

5.
Org Lett ; 14(20): 5346-9, 2012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-23035862

RESUMO

A new method has been developed for the enantioselective synthesis of highly functionalized hydropentalenes bearing up to four stereogenic centers with high stereoselectivity (up to 99% ee). This process combines an enantioselective organocatalytic anti-selective Michael addition with a highly efficient one-pot reduction/lactonization/Pauson-Khand reaction sequence. The structures and absolute configurations of the products were confirmed by X-ray analysis.

6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 43(4): 488-92, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-22997881

RESUMO

OBJECTIVE: Study the role for adipose tissue-derived stem cells (ADSCs) of secretome by adipose tissue and hoped that makes some contributions for the fat regeneration. METHODS: Direct adherent culture methods and the flow cytometry (FCM) were used to isolate and identify ADSCs. Collected the medium that had contained secreted proteins as the conditional medium (CM) and was used to induce ADSCs, chemical medium group as the positive control and normal medium group as the negative control. The formation of lipid drops was observed through the cell morphology, and the reliability was verified through Real-time PCR of the mRNA level in vitro. To test the effect of CM on ADSCs in vivo, the absorbable gelatin sponge was used as a scaffold for ADSCs. RESULTS: FCM ensured that the cultured cells were ADSCs. Significant increased lipid drops and related mRNA levels were observed in induced ADSCs cultured for 4 days, which indicated that the CM could promote the ADSCs differentiate into adipocytes after cultured for 4 days in vitro. The secreted proteins could promote ADSCS differentiate into vascularization tissues in vivo. CONCLUSION: The secreted proteome may contain some growth factors that can promote ADSCs to differentiate into adipocytes and vascularization, which may give new directions for the growth factors that could be applied in the repair of soft tissue.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Proteoma/metabolismo , Células-Tronco/citologia , Tecido Adiposo/citologia , Animais , Diferenciação Celular , Células Cultivadas , Neovascularização Fisiológica/efeitos dos fármacos , Proteoma/análise , Proteômica/métodos , Ratos , Ratos Sprague-Dawley
7.
Chem Commun (Camb) ; 48(63): 7790-2, 2012 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-22714728

RESUMO

Asymmetric formal [3+2] cycloadditions of 4-hydroxybut-2-enal, a succinaldehyde surrogate, and nitroalkenes with an organocatalyst provided cyclopentanecarbaldehydes containing four consecutive stereogenic centers with excellent enantioselectivities.

8.
Org Lett ; 14(2): 448-51, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22195677

RESUMO

Synthesis of isochromene pyrimidinedione derivatives having five stereocenters has been achieved by a one-pot Michael-Knoevenagel condensation-inverse-electron-demand hetero-Diels-Alder reaction of α, ß-unsaturated aldehydes, olefinic nitroalkanes, and 1,3-dimethylbarbituric acid via a one-pot strategy with excellent diastereo- and enantioselectivities (up to 99% ee). The structures and absolute configurations of the products were confirmed by X-ray analysis.

9.
J Am Chem Soc ; 133(15): 5708-11, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21438583

RESUMO

A six-coordinate oxovanadium(V) thiolate complex and an eight-coordinate non-oxovanadium thiolate complex, [PPh(4)][VO(PS3'')(OCH(3))] (1) and [NEt(4)][V(PS3'')(2)] (2) (PS3'' = P(C(6)H(3)-3-Me(3)Si-2-S)(3)(3-)), respectively, have been isolated and structurally characterized. The former belongs to a limited collection of oxovanadium(V) thiolate complexes. The latter has an unusual coordination number of eight. More importantly, its consensus electronic structure derived from its spectroscopic data should be considered as the resonance forms of V(V)-thiolate and V(IV)-thiyl radical species. This implies that V(IV)-thiyl radical can maintain a stable presence in biological systems.


Assuntos
Compostos de Sulfidrila/química , Vanadatos/química , Compostos de Vanádio/química , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Modelos Moleculares
10.
Org Lett ; 13(6): 1278-81, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21348453

RESUMO

Michael addition of carbethoxymethylenetriphenylphosphorane (a Wittig reagent) to nitroalkenes, followed by a reaction with ethyl formylformate and cinnamaldehydes, or formaldehyde and cinnamaldehydes, provided the respective pentasubstituted cyclopentanecarbaldehydes bearing a quaternary carbon center and pentasubstituted cyclohexanecarbaldehydes having five contiguous stereocenters with excellent enantioselectivities (up to >99% ee).

11.
Org Lett ; 13(6): 1338-41, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21348455

RESUMO

A synthesis of fully substituted cyclopentanes bearing a quaternary carbon center and five contiguous stereogenic centers has been achieved by sequential organocatalyzed Stetter and Michael-Aldol reactions of heteroaromatic aldehydes, nitroalkenes, and α,ß-unsaturated aldehydes via the [1 + 2 + 2] annulation strategy with dynamic kinetic asymmetric transformation and excellent enantioselectivities (up to >99% ee).

12.
Org Biomol Chem ; 9(2): 382-6, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21088771

RESUMO

Asymmetric domino Michael-acetalization reactions of 2-hydroxynitrostyrene and aldehydes "on water" followed by oxidation providing the cis-3,4-disubstituted dihydrocoumarins with excellent enantioselectivities (up to >99% ee). The variant with glutaraldehyde underwent a highly stereoselective domino Michael-acetalization-Henry reaction to afford the tetrahydro-6H-benzo[c]chromen-6-ones after the subsequent oxidation.

13.
Org Lett ; 12(21): 4812-5, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-20936853

RESUMO

A stereoselective synthesis of fully substituted cyclopentenes has been achieved by a sequential organocatalyzed Stetter and Michael-aldol condensation of aromatic aldehydes, nitroalkenes, and α,ß-unsaturated aldehydes via the [1 + 2 + 2] annulation strategy with excellent diastereoselectivities and enantioselectivities (up to >99% ee).

14.
Org Lett ; 12(4): 776-9, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20078081

RESUMO

The first asymmetric total synthesis of (+)-conicol has been achieved via a key step reaction involving the organocatalytic domino oxa-Michael-Michael-Michael-aldol condensation of 2-((E)-2-nitrovinyl)benzene-1,4-diol and alpha,beta-unsaturated aldehydes. Structures of the three-component domino reaction adducts, 20 and 21, including their absolute configurations, were confirmed unambiguously by X-ray analysis. Through this work, the absolute configuration of (+)-conicol was thereby elucidated.


Assuntos
Antineoplásicos/síntese química , Terpenos/síntese química , Aldeídos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Catálise , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Haplorrinos , Humanos , Biologia Marinha , Conformação Molecular , Estrutura Molecular , Estereoisomerismo , Terpenos/química , Terpenos/farmacologia , Urocordados/química
15.
Inorg Chem ; 49(3): 977-88, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20028109

RESUMO

A series of V(III) complexes of varying coordination number (5, 6, and 7) all containing the PS3 ligand (PS3 = trianion of tris(2-thiophenyl)phosphine and its derivatives with other phenyl substituents) has been prepared and structurally characterized. The complexes have general formula [V(PS3)L(n)](0,-), where n = 1 (from L = Cl(-), 1-Me-Im, N(3)(-)), 2 (from L = 2,2'-bpy; counting each N of the bidentate ligand), and 3 (from L = 1-Me-Im, N(2)H(4)). The complexes have also been investigated by direct current (DC) magnetic susceptibility and high-frequency and -field electron paramagnetic resonance (HFEPR). HFEPR, supported by magnetometry, has provided accurate spin Hamiltonian parameters that describe the S = 1 spin ground state of the complexes. Of particular interest are the zero-field splitting (zfs) parameters which, together with structural data, are the empirical starting point for detailed computational studies. The computational methods included density functional theory (DFT), which was only marginally successful, and more advanced ab initio methods (CASSCF and SORCI). The zfs in these complexes is relatively small in magnitude (|D| approximately 1 cm(-1)) and is the result of multiple, often counteracting, spin-orbit coupling (SOC) and spin-spin coupling (SSC) contributions. The specific origin of each of these contributions is described in detail. The results indicate the level of electronic structure calculation possible for transition metal complexes even with multiple unpaired electrons and highly covalent, heavier atom donor ligands.


Assuntos
Simulação por Computador , Modelos Químicos , Nitrogenase/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Teoria Quântica , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Elétrons , Modelos Moleculares , Estrutura Molecular , Nitrogenase/metabolismo , Compostos de Sulfidrila/química , Vanádio/química
16.
Org Lett ; 11(22): 5246-9, 2009 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-19852490

RESUMO

The stereoselective synthesis of all-cis 5-nitro-4,6-diphenylcyclohex-1-enecarboxylic ester has been achieved by an organocatalytic asymmetric Michael-Michael-Wittig cascade reaction of phosphorus ylides, nitroolefins, and alpha,beta-unsaturated aldehydes with excellent enantioselectivities (up to >99% ee).


Assuntos
Cicloexenos/síntese química , Nitrocompostos/síntese química , Compostos Organofosforados/química , Aldeídos/química , Alcenos/química , Catálise , Cristalografia por Raios X , Cicloexenos/química , Modelos Moleculares , Estrutura Molecular , Nitrocompostos/química , Estereoisomerismo
17.
Org Lett ; 10(12): 2345-8, 2008 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-18484729

RESUMO

Organocatalytic Michael reaction of glutaraldehyde and 3-arylpropenal followed by the subsequent intramolecular aldol condensation provided 2-arylcyclohex-3-ene-1,3-dicarbaldehydes. Reactions with the 5-oxohexanal variant afforded the highly functionalized cyclohexenedicarbaldehydes in high diastereoselectivity and high enantioselectivity (>99% ee). Structure of the adduct 3j was confirmed unambiguously by X-ray analysis.

18.
J Org Chem ; 72(22): 8459-71, 2007 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17919000

RESUMO

The highly enantioselective organocatalytic Robinson annulation of alpha,beta-unsaturated aldehydes was achieved, catalyzed by l-proline and trialkylamines and providing the formal [4 + 2] cycloaddition adducts. Additionally, in some examples in the catalysis with diarylpyrrolinol silyl ethers, the reactions afforded the [4 + 2] adducts with high enantioselectivity (>99.5% ee). The structure of the adduct, obtained from the reaction of 3-methylbut-2-enal and (E)-3-(2-nitrophenyl)acrylaldehyde, was confirmed by X-ray analysis. The absolute configurations of some [4 + 2] cycloadducts were investigated, and the methodology was applied in the synthesis of (+)-palitantin.


Assuntos
Aldeídos/química , Aminas/química , Cicloexanóis/síntese química , Cicloexanonas/síntese química , Prolina/química , Aldeídos/síntese química , Catálise , Cristalografia por Raios X , Ciclização , Cicloexanóis/química , Cicloexanonas/química , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
19.
Org Lett ; 8(11): 2217-20, 2006 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16706490

RESUMO

[reaction: see text] The first highly enantioselective organocatalyzed carbo [3 + 3] cascade cycloaddition of alpha,beta-unsaturated aldehydes is reported. Using this methodology, crotonaldehyde is converted to 6-hydroxy-4-methylcyclohex-1-enecarbaldehyde, which is used in the synthesis of (-)-isopulegol hydrate, (-)-cubebaol, and p-tolualdehyde as well as (-)-6-hydroxy-4-methyl-1-cyclohexene-1-methanol acetate, an intermediate in the total synthesis of lycopodium alkaloid magellanine. Other alpha,beta-unsaturated aldehydes give rise to chiral cyclohexadienes via formal [4 + 2] reactions.


Assuntos
Aldeídos/química , Prolina/química , Terpenos/síntese química , Alcaloides/biossíntese , Catálise , Ciclização , Monoterpenos Cicloexânicos , Lycopodium/química , Estrutura Molecular , Prolina/análogos & derivados , Estereoisomerismo , Terpenos/química
20.
Carbohydr Res ; 340(16): 2457-68, 2005 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-16169539

RESUMO

Both cis- and trans-2-substituted-1,2,3,6-tetrahydro-pyridin-3-ols have been prepared via an aldol condensation-ring-closing metathesis sequence. A stereodivergent synthesis of optionally functionalized deoxyimino sugars was achieved via asymmetric dihydroxylation or epoxidation/nucleophilic substitution of these tetrahydropyridines.


Assuntos
Desoxiaçúcares/síntese química , Imino Açúcares/síntese química , Cristalografia por Raios X , Desoxiaçúcares/química , Imino Açúcares/química , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
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