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1.
Anat Rec (Hoboken) ; 2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31930662

RESUMO

Ovarian cancer (OC) is one of the most aggressive female cancers in the world. OC trends to be diagnosed at an advanced stage with abdominal metastasis. Our study explored the biological function and underlying mechanism of lncRNA on OC cell proliferation and migration. The expression of turine up-regulated gene 1 (TUG1) in human OC tissues and cell lines was measured by qRT-PCR. OC cell proliferation, viability, migration, and invasion were measured by MTT assays, colony formation assays, and transwell assays in vitro. Furthermore, the nude mice xenograft model was established to determine the effects of TUG1 in vivo. The relationship between TUG1 and miR-29b-3p, as well as miR-29b-3p and MDM2 were identified using the luciferase reporter assays. We showed that the expression of TUG1 and MDM2 were significantly increased, but the expression of miR-29b-3p was remarkably decreased in OC tissues and cell lines. Knockdown of TUG1 strongly inhibited the ability of cell proliferation, colony formation, migration, and invasion in vitro. The relationship between TUG1 and miR-29b-3p, or miR-29b-3p and MDM2 were predicted by StarBase and miRanda online software. Besides, miR-29b-3p reversed the positive effect of TUG1 on the OC cell proliferation, migration, and invasion through inhibiting MDM2 expression and increasing p53 phosphorylation level. Moreover, knockdown of TUG1 suppressed tumor growth in vivo. Taken all together, this study shows that TUG1 plays a crucial oncogenic role and facilitates cell proliferation, migration, and invasion in OC through regulating miR-29b-3p/MDM2 axis.

2.
Angew Chem Int Ed Engl ; 58(49): 17690-17694, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31591793

RESUMO

Open-cage fullerenes with a 19-membered orifice were prepared in three steps from C60 . The key step for cage-opening is aniline mediated ring expansion of a fullerene-mixed peroxide with a ketolactone moiety on the orifice. Release of ring strain on the spherical fullerene cage served as the main driving force for the efficient cage-opening sequence. Encapsulation of oxygen could be achieved at room temperature under moderate pressure (50 atm) and the encapsulated oxygen could be released slowly under ambient conditions. The activation energy of the oxygen-releasing process is 18.8 kcal mol-1 and the half-life at 37 °C was 73 min, which makes this open-cage fullerene derivative a potential oxygen-delivery material.

3.
R Soc Open Sci ; 5(8): 180897, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225079

RESUMO

Resulting from the drastic increase of atmospheric CO2 concentration day by day, global warming has become a serious environmental issue nowadays. The fixation of CO2 to obtain desirable, economically competitive chemicals has recently received considerable attention. This work investigates the fixation of CO2 along with three bromopyridines via a facile electrochemical method using a silver cathode to synthesize picolinic acids, which are important industrial and fine chemicals. Cyclic voltammetry is employed to investigate the cyclic voltammetric behaviour of bromopyridines. In addition, systematic study is conducted to study the relationships between the picolinic acids' yield and the electrolysis conditions and intrinsic parameters. The results show that the target picolinic acids' yields are strongly dependent on various conditions such as solvent, supporting electrolyte, current density, cathode material, charge passed, temperature and the nature of the substrates. Moreover, in the studied electrode materials such as Ag, Ni, Ti, Pt and GC, electrolysis and cyclic voltammetry show that Ag has a good electrocatalytic effect on the reduction and carboxylation of bromopyridine. This facile electrochemical route for fixation of CO2 provides an indispensable reference for the conversion and utilization of CO2 under mild conditions.

4.
Org Lett ; 20(11): 3332-3336, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29771129

RESUMO

A series of bibenzo[ b][1,4]thiazines with various functional groups has been synthesized by a free-radical condensation reaction. Bibenzo[ b][1,4]thiazines were obtained in moderate to good yield (up to 85%) through a one-step reaction of readily available 2,2'-dithiodianiline and methyl aryl ketones with AIBN as radical initiator in HOAc. Bibenzo[ b][1,4]thiazines exhibit diversiform solid-state packing.

5.
Org Lett ; 20(2): 477-480, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29313691

RESUMO

A novel metal-free one-pot protocol for the effective and efficient synthesis of 3-phosphinoylbenzofurans via a phospha-Michael addition/cyclization of H-phosphine oxides and in situ generated ortho-quinone methides is described. Based on the expeditious construction of C(sp2)-P bonds, asymmetric synthesis of optically pure 3-phosphinoylbenzofurans containing chiral P-stereogenic center has also been probed by using chiral RP-(-)-menthyl phenylphosphine oxide.

6.
Chemistry ; 24(2): 451-457, 2018 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-29114980

RESUMO

An open-cage C60 derivative 9 with anilino, hemiketal, and lactone moieties on the edge of the opening was prepared through a fullerene-mixed peroxide procedure. Key steps include decarbonylation, intramolecular Friedel-Crafts reaction and oxetane ring opening rearrangement. The open-cage compound 9 readily reacts with various metal salts. A nickel complex was obtained by treating 9 with NiCl2 at r.t. followed by purification on a silica gel column. Single-crystal X-ray diffraction analysis showed that the nickel ion is coordinated to two ligands with an octahedral geometry.

7.
Dalton Trans ; 47(3): 726-733, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29230458

RESUMO

By the combination of Pd-complexes and [V10O28]6-, three Pd-decavanadate compounds [Pd(NH3)4]3[V10O28]·8H2O (1), [Pd(deta)(H2O)]2(NH4)2[V10O28]·2H2O (2) (deta = diethylenetriamine) and [Pd(dpa)2](Hdpa)2(Et3NH)2[V10O28]·2H2O (3) (dpa = 2,2'-dipyridylamine) have been successfully synthesized and thoroughly characterized using single X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR) and elemental analyses (EA). Interestingly, in the three compounds, the molar ratios of Pd to decavanadate vary from 3 : 1 to 1 : 1 by changing N-ligands. The three Pd-decavanadates as heterogeneous catalysts are active in the aerobic oxidation of benzylic hydrocarbons under solvent-free conditions without adding any additives and co-catalysts. Moreover, compound 1 can be reused three times without losing its activity.

8.
Org Lett ; 17(1): 142-5, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25521011

RESUMO

P,C-stereogenic 1,3-bisphosphinylpropanes 3 that have up to five stereogenic centers could be obtained stereoselectively in high yields by a one-step reaction of (RP)-menthylphenylphosphine oxide 1 with α,ß-unsaturated aldehydes 2 catalyzed by KOH at room temperature. A mechanism was proposed as to involve a stereoselective intermolecular 1,3'-phosphorus migration from the 1,2-adduct of 1 with 2 to another 2 generating a 1,4-adduct that subsequently reacts with 1 to produce 3.


Assuntos
Ácidos Fosfínicos/síntese química , Propano/síntese química , Aldeídos/química , Catálise , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ácidos Fosfínicos/química , Propano/análogos & derivados , Propano/química , Estereoisomerismo
9.
Org Biomol Chem ; 12(46): 9457-65, 2014 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-25327336

RESUMO

Aromatic methyl ketones and cyclic asymmetric ketones underwent hydrophosphorylation with P-stereogenic H-P species in the presence of potassium carbonate to produce P,C-stereogenic tertiary α-hydroxyl phosphinates in excellent yields with up to 99 : 1 dr. The diastereoselectivity was induced by a reversible conversion of less stable stereomer of product to that of a more stable one via an equilibrium, which was confirmed by aldehyde/ketone exchanging reaction. Toward the exchange, aliphatic or aldehyde carbonyl were more active than aromatic or ketone carbonyls, respectively. The stability difference between the two diastereomers was controlled by the sizes of substituents linking to phosphorus or α-carbon.


Assuntos
Aldeídos/química , Cetonas/química , Ácidos Fosfínicos/química , Carbono/química , Carbonatos/química , Catálise , Estrutura Molecular , Fósforo/química , Potássio/química , Estereoisomerismo
11.
J Org Chem ; 78(3): 1157-62, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23311689

RESUMO

Four isomers are currently known for the trioxygenated fullerene derivative C(60)(O)(3), three regioisomers with all of the oxygen addends as epoxy groups and the unstable ozonide isomer with a 1,2,3-trioxlane ring. Here we report the synthesis of an open-cage isomer for C(60)(O)(3) with a ketolactone moiety embedded into the fullerene skeleton through a three-step procedure mediated by fullerene peroxide chemistry. Two fullerene skeleton carbon-carbon bonds are cleaved in the process. The open-cage derivative C(60)(O)(3) can be converted back to C(60) through deoxygenation with PPh(3). Single crystal X-ray structure confirmed the open-cage structure.


Assuntos
Fulerenos/química , Lactonas/química , Cristalografia por Raios X , Isomerismo , Conformação Molecular , Estrutura Molecular , Estereoisomerismo
13.
J Org Chem ; 77(5): 2456-62, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22324338

RESUMO

A series of isomerically pure alkynyl-substituted fullerenol derivatives such as C(60)(OH)(6)(O(CH(2))(3)CCH)(2) were synthesized through Lewis acid catalyzed epoxy ring opening and/or S(N)1 replacement reactions starting from the fullerene-mixed peroxide C(60)(O)(t-BuOO)(4). Copper-catalyzed azide-alkyne cycloaddition readily converted the terminal alkynyl groups into triazole groups. Intramolecular oxidative alkyne coupling afforded a fullerenyl crown ether derivative.


Assuntos
Alquinos/química , Éteres de Coroa/química , Fulerenos/química , Estrutura Molecular , Estereoisomerismo
14.
J Org Chem ; 76(6): 1735-41, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21314104

RESUMO

Bromine reacts with the 1,2-bisadduct C(60)(OOtBu)(2) efficiently to form the cyclopentadienyl-type compound 4 (C(60)(OOtBu)(2)Br(4)). In the presence of AgClO(4), the four bromine atoms can be replaced regioselectively by methoxyl groups in a stepwise fashion to form C(60)(OOtBu)(2)Br(4-x)(OMe)(x). A second alcohol may be introduced by treating partially methoxylated compound 6 (C(60)(OOtBu)(2)Br(2)(OMe)(2)) with ROH/AgClO(4). Other related reactions have been investigated to explore the reactivity patterns. The structure of compound 6 was confirmed by single crystal X-ray analysis.

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