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111.
Mário L.A.A. Vasconcellos Mauro L. Mellão Uendel G. Barreiros Marcelo C. Branco Maria T.P.Gambardella Oduvaldo F. Ramos 《合成通讯》2013,43(21):4077-4085
New alcohols 3d, 3e and 3f were efficiently prepared in enantiopure form (2 steps, 50–58%), from available 1-(R)-(+)-camphor 1. The absolute configurations were assigned by NMR and relative X-ray crystallographic analysis. 相似文献
112.
Alessandra S. Kiametis João B. L. Martins Luiz A. S. Romeiro Ricardo Gargano 《International journal of quantum chemistry》2013,113(10):1461-1466
Alzheimer's disease is the leading cause of dementia for elderly people. The main active therapeutic is supported on the increased levels of acetylcholine in the synaptic cleft, based on reversible inhibition of the acetylcholinesterase (AChE) enzyme. This article aims to propose possible inhibitor candidates for AChE, designed from nonisoprenoid lipids of cashew (Anacardium occidentale), and based on several electronic properties. These electronic properties were obtained through B3LYP/6‐311+G(2d,p) calculation level. Principal component analysis reveals that from the set of studied molecular structures a small group is correlated with donepezil, a drug with known biological activity. © 2012 Wiley Periodicals, Inc. 相似文献
113.
Manoel Carneiro Oliveira‐Junior Aldaíza Salomão Monteiro Ernesto César Pinto Leal‐Junior Egberto Munin Rodrigo Aléxis Lazo Osório Wellington Ribeiro Rodolfo Paula Vieira 《Photochemistry and photobiology》2013,89(1):173-178
This study investigated the effects of low‐level laser therapy (LLLT) in the liver function, structure and inflammation in a experimental model of carbon tetrachloride (CCl4)‐induced liver cirrhosis. Wistar rats were divided into Control, LLLT, CCl4 and CCl4+LLLT groups. CCl4 groups received CCl4 (0.4 g kg?1; i.p.), three times a week, for 12 weeks. A 830 nm LLLT was performed with a continuous wave, 35 mW, 2.5 J cm?2 per point, applied to four points of the liver (right and left upper and lower extremities, in the four lobes of the liver) for 2 weeks. Liver structure and inflammation (cirrhotic areas, collagen deposition, inflammation, density of Kupffer and hepatic stellate cells) and function (aspartate aminotransferase, alkaline phosphatase, gamma glutamyltransferase, lactate dehydrogenase, total proteins and globulins) were evaluated. LLLT significantly reduced CCl4‐increased aspartate aminotransferase (P < 0.001), alkaline phosphatase (P < 0.001), gamma‐glutamyl transferase (P < 0.001) and lactate dehydrogenase (P < 0.01) activity, as well as total proteins (P < 0.05) and globulins (P < 0.01). LLLT also reduced the number of cirrhotic areas, the collagen accumulation and the hepatic inflammatory infiltrate. Of note, LLLT reduced CCl4‐increased number of Kupffer cells (P < 0.05) and hepatic stellate cells (P < 0.05). We conclude that LLLT presents beneficial effects on liver function and structure in an experimental model of CCl4‐induced cirrhosis. 相似文献
114.
Paula Gomes Maria João Araújo Eduardo F. Marques Soraia Falcão Rodrigo O. Brito 《合成通讯》2013,43(12):2025-2036
Double-chained surfactants with potential biocompatibility have been prepared in high yields by lysine acylation with four natural saturated fatty acids (C6 to C12) and with cis-undec-5-enoic acid. The surfactants were found to assemble into nanotubules in aqueous medium and, when mixed with a commercial cationic surfactant, to spontaneously form liposomes. 相似文献
115.
Ultrasonic irradiation substantially improves the reaction of cyclohexene with I2 in aqueous dioxane in the presence of Cu(OAc)2 · H2O to generate the expected iodohydrin in high yield. The product undergoes cyclization to the epoxide by biphasic treatment with either Na2CO3 or KOH in a sonication‐sensitive step. 相似文献
116.
Dihalocarbenes generated under phase transfer conditions add to cis and trans vinylic selenides to give the corresponding 1,1-dihalo-2-selenocyciopropanes with retention of configuration. 相似文献
117.
118.
Thiago Henrique Napoleão Teodomiro Gomes dos Santos-Filho Emmanuel Viana Pontual Rodrigo da Silva Ferreira Luana Cassandra Breitenbach Barroso Coelho Patrícia Maria Guedes Paiva 《Applied biochemistry and biotechnology》2013,171(3):744-755
This work reports the use of matrices containing Cratylia mollis lectins (Cramoll 1,2,3-Sepharose and Cramoll 3-Sepharose) for isolation of glycoproteins from fetal bovine serum, human colostrum, hen egg white, and human blood plasma. Cramoll 1,2,3-Sepharose was able to bind a glycoprotein from fetal bovine serum which showed the same fetuin electrophoretic profile. The data indicate that this protein adsorbed to the matrix by interaction with Cramoll 3. Cramoll 1,2,3-Sepharose was not efficient to retain glycoproteins from human colostrum or commercial ovalbumin. Cramoll 3-Sepharose bound ovalbumin, and the support retained protein from hen egg white. Protein peaks eluted from the column with 1.0 M NaCl or 0.3 M galactose showed apparent molecular mass of ovalbumin. Two main proteins from blood plasma with apparent molecular mass 67 (similar to albumin) and 50 kDa (similar to fetuin) adsorbed on Cramoll 3-Sepharose and were eluted with 1.0 M NaCl as a single peak. Elution of adsorbed plasma proteins with 0.3 M galactose was less selective than with 1.0 M NaCl as revealed by SDS-PAGE. In conclusion, the Cramoll 1,2,3-Sepharose and Cramoll 3-Sepharose matrices were useful to separate glycoproteins from complex protein mixtures, and the adsorption phenomena was a carbohydrate-dependent event. 相似文献
119.
Theolyta S. Araújo Claudener S. Teixeira Maria A. P. Falcão Vanir R. Pinto Junior Mayara Quiroz Santiago Raquel G. Benevides Plínio Delatorre Jorge L. Martins Magna S. Alexandre-Moreira Benildo S. Cavada Eliane A. Campesatto Bruno A. M. Rocha 《Applied biochemistry and biotechnology》2013,171(8):1944-1955
Lectins are a structurally heterogeneous group of proteins or glycoproteins with at least one noncatalytic domain binding reversibly to a specific mono- or oligosaccharide. Monocot mannose-binding lectins are an extended superfamily of structurally and evolutionarily related proteins. In this study, we evaluated anti-inflammatory and antinociceptive effects of monocot lectin from the Canna limbata seeds (CLL). To accomplish this, CLL was purified and subjected to pharmacological assays: abdominal writhing induced by acetic acid, formalin, hot plate and Zymosan A-induced peritonitis tests. The CLL was purified by chromatographic chitin column, and the relative mass of 21 kDa observed in electrophoresis was confirmed by electrospray mass spectrometry, which also revealed that purified CLL consists of a dimer having a weight of 49,676 Da. The CLL showed nociceptive activity in the acetic acid test as well as peripheral antinociceptive response. The CLL also showed anti-inflammatory effect with the reduction of inflammation in the formalin test and neutrophil migration into the peritoneal cavity. This is the first report of anti-inflammatory activity for a monocot lectin, and it suggests a new pharmacological tool to understand inflammatory and antinociceptive processes mediated through lectins. 相似文献
120.
Janaína Versiani dos Anjos Rajendra M. Srivastava Silene Carneiro do Nascimento Sebastião J. de Melo 《Journal of carbohydrate chemistry》2013,32(4):258-277
A copper‐catalyzed reaction of propargyl 4,6‐di‐O‐acetyl‐2,3‐dideoxy‐α‐D‐erythro‐hex‐2‐enopyranoside with 3‐(4‐azidophenyl)‐1,2,4‐oxadiazoles gave the corresponding hexenopyranosides bearing an 1,2,4‐oxadiazole subunit in the aglyconic part of the molecule. The same reaction between ethyl 4‐azido‐2,3,4‐trideoxy‐α‐D‐erythro‐hex‐2‐enopyranoside and acetylenic 1,2,4‐oxadiazoles afforded the corresponding hexenopyranosides carrying a triazole and a 1,2,4‐oxadiazole ring at C‐4 of the carbohydrate. Combination of the two sequences gave hexenopyranosides displaying two 1,2,4‐oxadiazole subunits, each one being embedded in the C‐1 and C‐4 frameworks, of the carbohydrate moiety. A simple dihydroxylation reaction of these unsaturated carbohydrates yielded a series of mannopyranosides bearing one or two 1,2,4‐oxadiazole subunits at C‐1 or C‐4. These new compounds were evaluated for their cytotoxic activities against two cell strains: NCI‐H292 (lung carcinoma) and Hep‐2 (larynx carcinoma), some of them presenting impressive cell growth inhibitions. 相似文献