Search results for " molecule"
showing 10 items of 1523 documents
Semicarbazide-sensitive amine oxidase/vascular adhesion protein-1 deficiency reduces leukocyte infiltration into adipose tissue and favors fat deposi…
2009
1525-2191 (Electronic) Journal Article; Obesity is associated with low-grade inflammation and leukocyte infiltration in white adipose tissue (WAT) and is linked to diabetic complications. Semicarbazide-sensitive amine oxidase, also known as vascular adhesion protein-1 (SSAO/VAP-1), is a membrane protein that is highly expressed in adipocytes and is also present on the endothelial cell surface where it is involved in leukocyte extravasation. We studied fat deposition and leukocyte infiltration in WAT of mice with a null mutation in the amine oxidase copper-containing-3 (AOC3) gene encoding SSAO/VAP-1. Both epididymal and inguinal WATs were larger in 6-month-old AOC3-KO males than in age-matc…
Construction of Chimeric Dual-Chain Avidin by Tandem Fusion of the Related Avidins
2011
BackgroundAvidin is a chicken egg-white protein with high affinity to vitamin H, also known as D-biotin. Many applications in life science research are based on this strong interaction. Avidin is a homotetrameric protein, which promotes its modification to symmetrical entities. Dual-chain avidin, a genetically engineered avidin form, has two circularly permuted chicken avidin monomers that are tandem-fused into one polypeptide chain. This form of avidin enables independent modification of the two domains, including the two biotin-binding pockets; however, decreased yields in protein production, compared to wt avidin, and complicated genetic manipulation of two highly similar DNA sequences i…
Theoretical and experimental NMR studies on muscimol from fly agaric mushroom (Amanita muscaria)
2015
In this article we report results of combined theoretical and experimental NMR studies on muscimol, the bioactive alkaloid from fly agaric mushroom (Amanita muscaria). The assignment of (1)H and (13)C NMR spectra of muscimol in DMSO-d6 was supported by additional two-dimensional heteronuclear correlated spectra (2D NMR) and gauge independent atomic orbital (GIAO) NMR calculations using density functional theory (DFT). The effect of solvent in theoretical calculations was included via polarized continuum model (PCM) and the hybrid three-parameter B3LYP density functional in combination with 6-311++G(3df,2pd) basis set enabled calculation of reliable structures of non-ionized (neutral) molecu…
Unexpected identification and characterization of a cathinone precursor in the new psychoactive substance market: 3',4'-methylenedioxy-2,2-dibromobut…
2019
Abstract 3′,4′-methylenedioxy-2,2-dibromobutyrophenone has been identified and fully characterized in a sample obtained from an anonymous consumer acquired as ketamine through the Internet market. The substance has been deeply characterized by using standard and high performance analytical techniques such as: attenuated total reflectance-infrared spectroscopy, gas chromatography–mass spectrometry, high-resolution mass spectrometry, elemental analysis, and nuclear magnetic resonance, including 1H, 13C, distortionless enhancement by polarization transfer, two dimensional homonuclear 1H-1H correlation spectroscopy, and 1H-13C heteronuclear single-quantum correlation spectra. 3′,4′-methylenedio…
Acylated triterpene saponins from Silene jenisseensis
1995
Abstract From the roots of Silene jenisseensis a new trans-p-methoxycinnamoyl triterpene saponin has been isolated along with its cis-p-methoxycinnamoyl isomer as an inseparable mixture. Their structures were established by chemical means and spectroscopic methods including 1D- and 2D-homonuclear and heteronuclear correlation NMR spectroscopy as 3-O-[β- d -galactopyranosyl -(1 → 2)-β- d -glucuronopyranosyl ]-28-O-[β- d -glucopyranosyl -(1 → 2)-α- l - rhamnopyranosyl -(1 → 2)-β- d -4-O-trans-p- methoxycinnamoyl-fucopyranosyl ] quillaic acid and its cis-isomer, respectively. They did not show any activity in the in vitro chemoluminescence granulocytes assay, but exhibited only a weak inhibito…
Synthesis of N-diisopropyl phosphoryl benzyl-tetrahydroisoquinoline, a new class of mitochondrial complexes I and III inhibitors
2000
The synthesis of N-(O,O-diisopropylphosphoryl)-benzyltetrahydroisoquinoline (3) has been achieved in a 'one pot' procedure from imine (2) and diisopropyl-phosphorochloridate (1) generated in situ (POCl3 + iPrOH). Compound 3 is the first benzyltetrahydroisoquinoline derivative found to be a potent inhibitor of mitochondrial complexes I and III, and therefore it opens a new perspective with this series of compounds as they can be considered as new class of antitumor agents.
Squarroside A, a biologically active triterpene saponin from Acanthophyllum squarrosum.
1993
A new bioactive saponin has been isolated from the roots of Acanthophyllum squarrosum. Based on spectroscopic data, especially direct and long-range heteronuclear 2D NMR analysis, and on chemical transformations, the structure of this new compound was elucidated as 3-O-beta-D-galactopyranosyl-(1--2)-[beta-D-xylopyranosyl-(1--3)]-beta- D-glucuronopyranosyl gypsogenin 28-O-beta-D-xylopyranosyl-(1--4)-alpha-L- rhamnopyranosyl-(1--2)-[alpha-L-arabinofuranosyl-(1--3)]-beta-D-4-O- acetylfucopyranoside for which we proposed the name squarroside A. This molecule showed a concentration dependent immunomodulatory effect in the in vitro lymphocyte transformation test.
Bidentatoside I, a New Triterpene Saponin from Achyranthes bidentata
2001
Bidentatoside I (1) is a new triterpene saponin bearing an unusual dioxopropionic acid unit, isolated from the roots of Achyranthes bidentata. Structural elucidation was performed mainly by chemical and homo- and heteronuclear 2D NMR techniques. This compound did not show any potentiation of the in vitro cytotoxicity of cisplatin in the HT 29 human colon cancer cell line.
Jenisseensosides C and D, biologically active acylated triterpene saponins from Silene jenisseensis
1997
Abstract We previously reported the isolation and structure elucidation of a new trans - p -methoxycinnamoyl triterpene-saponin along with its cis - p -methoxycinnamoyl isomer as an inseparable mixture from the roots of Silene jenisseensis . In a continuing study on this plant, two additional new acylated triterpene-saponins were obtained as an inseparable mixture. Their structures have been established by chemical means and spectroscopic methods including 1D and 2D homonuclear and heteronuclear correlation NMR spectroscopy as 3- O -[β- d -galactopyranosyl-(1 → 2)-β- d -glucuronopyranosyl]-28- O -[{α- l -rhamnopyranosyl-(1 → 2)}- {4- O - trans - p -methoxycinnamoyl}-β- d -fucopyranosyl] qui…
Chromone and phenanthrene alkaloids from Dennettia tripetala.
2002
Dennettine, a new 2,6-dimethoxychromone and three known phenanthrene alkaloids (uvariopsine, stephenanthrine and argentinine) in addition to the phenolic and known compound vanillin were isolated from the roots of Dennettia tripetala. Their structures were determined by physical and spectroscopical one dimensional (1D) and 2D-NMR analysis, including heteronuclear multiple bond correlation and nuclear Overhauser enhancement spectroscopy.