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91.
Ruiz-Pérez MV Pino-Ángeles A Medina MA Sánchez-Jiménez F Moya-García AA 《Journal of chemical information and modeling》2012,52(1):113-119
Histidine decarboxylase (HDC) and l-aromatic amino acid decarboxylase (DDC) are homologous enzymes that are responsible for the synthesis of important neuroactive amines related to inflammatory, neurodegenerative, and neoplastic diseases. Epigallocatechin-3-gallate (EGCG), the most abundant catechin in green tea, has been shown to target histamine-producing cells and to promote anti-inflammatory, antitumor, and antiangiogenic effects. Previous experimental work has demonstrated that EGCG has a direct inhibitory effect on both HDC and DDC. In this study, we investigated the binding modes of EGCG to HDC and DDC as a first step for designing new polyphenol-based HDC/DDC-specific inhibitors. 相似文献
92.
Perfluorinated compounds (PFCs) are ubiquitous contaminants of humans and animals worldwide. PFCs are bioaccumulated because
of their affinity for proteins. It has been shown they could have a variety of toxicological effects and cause damage to human
health, emphasizing the need for sensitive and robust analytical methods to assess their bioaccumulation in humans. In this
paper we report the development and validation of an analytical method for analysis of PFCs in the non-invasive human matrices
hair and urine. The method is based on rapid and simple sample pre-treatment followed by online turbulent flow liquid chromatography
and tandem mass spectrometry (TFC–LC–MS–MS) for analysis of 21 PFCs. The method was validated for both matrices. Percentage
recovery was between 60 and 105 for most compounds in both matrices. Limits of quantification ranged from 0.1 to 9 ng mL−1 in urine and from 0.04 to 13.4 in hair. The good performance of the method was proved by investigating the presence of selected
PFCs in 24 hair and 30 urine samples from different donors living in Barcelona (NE Spain). The results were indicative of
bioaccumulation of these compounds in both types of sample. PFOS and PFOA were most frequently detected in hair and PFBA in
urine. 相似文献
93.
Esther Caballero Dulce Alonso Concepción Alvarez Francisca Sanz Fernando Tomé 《Tetrahedron letters》2004,45(8):1631-1634
New 1-phthalimido-4-(3-indolyl)-2-trialkylsiloxy-1,3-butadienes were easily prepared from 1,3-dichloropropanone and their configurations were established from NMR data. Their Diels-Alder reactivity with different maleimides and quinones was studied, high yields of the exo cycloadducts being obtained, as confirmed by X-ray diffraction studies. 相似文献
94.
A series of racemic 4-aryl-5-(tert-butoxycarbonyl)-6-methyl-3,4-dihydro-2(1H)-pyridones have been prepared by means of a modified Hantzsch reaction using commercially available starting materials. An easy removal of the tert-butyl group of these pyridones and subsequent reaction with cesium carbonate and chloromethyl 2-methylpropanoate provided us suitable substrates (±)-5 to be used in lipase-catalyzed hydrolysis reactions. Lipase B from Candida antarctica (CAL-B) was the most adequate lipase in the hydrolysis of (±)-5. Despite the low enantioselectivity values obtained (E≤12), several optically active pyridone derivatives were finally isolated with high enantiomeric excesses (ee≥91%) and moderate yields. 相似文献
95.
We report here a simple entry into the nitrostilbene system in very short reaction times and good yields using the microwave-assisted Wittig reaction in phase-transfer conditions of nitro-substituted benzyltriphenylphosphonium ylides with aldehydes. 相似文献
96.
Dr. Moustafa Malki Dr. Santiago Casado Dr. María Francisca López Dr. Renaud Caillard Dr. F. Javier Palomares Dr. José A. Martín Gago Dr. Cristina Vaz‐Domínguez Dr. Angel Cuesta Prof. Ricardo Amils Prof. Víctor M. Fernández Dr. Marisela Velez Dr. Antonio L. De Lacey Dr. David Olea 《Chemphyschem》2013,14(6):1237-1244
The biofilm formation of a strain of the extremophile bacterium Acidiphilium sp., capable of donating electrons directly to electrodes, was studied by different surface characterization techniques. We develop a method that allows the simultaneous study of bacterial biofilms by means of fluorescence microscopy and atomic force microscopy (AFM), in which transparent graphitic flakes deposited on a glass substrate are used as a support for the biofilm. The majority of the cells present on the surface were viable, and the growth of the biofilms over time showed a critical increase of the extracellular polymeric substances (EPS) as well as the formation of nanosized particles inside the biofilm. Also, the presence of Fe in Acidiphilium biofilms was determined by X‐ray photoelectron spectroscopy (XPS), whereas surface‐enhanced infrared absorption spectroscopy indicated the presence of redox‐active proteins. 相似文献
97.
Hiranthi Jayasuriya KithsiriB. Herath Chaowei Zhang DeborahL. Zink Angela Basilio Olga Genilloud MariaTeresa Diez Francisca Vicente Ignacio Gonzalez Oscar Salazar Fernando Pelaez Richard Cummings Sookhee Ha Jun Wang SheoB. Singh 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2007,119(25):4768-4772
98.
Anayive P. Rebolledo Geraldo M. de Lima Lillian N. Gambi Nivaldo L. Speziali Daniel F. Maia Carlos B. Pinheiro Jos D. Ardisson Maria Esperanza Corts Heloisa Beraldo 《应用有机金属化学》2003,17(12):945-951
Three tin(IV) complexes of 2‐benzoylpyridine N(4)‐phenylthiosemicarbazone (H2Bz4Ph) were prepared: [Sn(L)Cl3] (1), [BuSn(L)Cl2] (2) and [(Bu)2Sn(L)Cl] (3), in which L stands for the anionic ligand formed upon complexation with deprotonation and release of HCl. The complexes were characterized by a number of spectroscopic techniques. The crystal structures of H2Bz4Ph and complex 3 were determined. The antifungal activity of the ligand and its tin(IV) complexes was tested against Candida albicans. The thiosemicarbazone proved to be more active than the tin(IV) complexes. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
99.
Fernando J. S. Oliveira Leonardo Vazquez Norberto P. De Campos Francisca P. de Fran?a 《Applied biochemistry and biotechnology》1996,131(1-3):727-737
Biosurfactants production by a strain of Pseudomonas aeruginosa using palm oil as a sole carbon source was investigated. The experiments were carried out in 500-mL conical flasks containing
100 mL of mineral media supplemented with palm oil as the sole carbon source. The P. aeruginosa FR strain was able to reduce surface tension of three tested inorganic media. Rotation velocities from 100 to 150 rpm provided
free-cell fermented media with the lowest surface tension of approx 33 mN/m. Emulsification index results of even 100% were
achieved when diesel was used as oil phase. Eight surface-active compounds produced by the bacterium were identified by mass
spectrometry. 相似文献
100.
The synthesis and characterization of three heteronuclear Pt(2)Pd(2) (4, 5) and PtPd(2) (6) complexes of the model nucleobase 9-methyladenine (9-MeA) is reported. The compounds were prepared by reacting [Pt(NH(3))(3)(9-MeA-N7)](ClO(4))(2) (1) with [Pd(en)(H(2)O)(2)](ClO(4))(2) at different ratios r between Pt and Pd, with the goal to probe Pd(II) binding to any of the three available nitrogen atoms, N1, N3, N6 or combinations thereof. Pd(II) coordination occurs at N1 and at the deprotonated N6 positions, yet not at N3. 4 and 5 are isomers of [{(en)Pd}(2){N1,N6-9-MeA(-)-N7)Pt(NH(3))(3)}(2)](ClO(4))(6)·nH(2)O, with a head-head orientation of the two bridging 9-MeA(-) ligands in 4 and a head-tail orientation in 5. 6 is [{(en)Pd}(2)(OH)(N1,N6-9MeA(-)-N7)Pt(NH(3))(3)](ClO(4))(4)·4H(2)O, hence a condensation product between [Pt(NH(3))(3)(9-MeA-N7)](2+) and a μ-OH bridged dinuclear (en)Pd-OH-Pd(en) unit, which connects the N1 and N6 positions of 9-MeA(-) in an intramolecular fashion. 4 and 5, which slowly interconvert in aqueous solution, display distinct structural differences such as significantly different intramolecular Pd···Pd contacts (3.124 0(16) ? in 4; 2.986 6(14) ? in 5), among others. Binding of (en)Pd(II) to the exocyclic N6 atom in 4 and 5 is accompanied by a large movement of Pd(II) out of the 9-MeA(-) plane and a trend to a further shortening of the C6-N6 bond as compared to free 9-MeA. The packing patterns of 4 and 5 reveal substantial anion-π interactions. 相似文献