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" no prazo de Papéis
Pablo Etayo et al.
Chemical Society reviews, 42(2), 728-754 (2012-11-08)
During the last few decades, rhodium-catalysed asymmetric hydrogenation of diverse alkene classes has emerged as a powerful synthetic tool in the pharmaceutical industry, contributing to the manufacturing of chiral drugs, recent drug candidates for clinical trials, and major synthetic precursors
N Katsaros et al.
Critical reviews in oncology/hematology, 42(3), 297-308 (2002-06-07)
The antitumor activity of the inorganic complex cis-diammine-dichloroplatinum(II) (cisplatin) led to the development of other types of non-organic cytostatic drugs. Numerous platinum other platinum and non-platinum metal compounds were shown to be effective against animal model tumors as well as
Andreja Bakac
Dalton transactions (Cambridge, England : 2003), (13)(13), 1589-1596 (2006-03-21)
In aqueous solutions, as in organic solvents, rhodium hydrides display the chemistry of one of the three limiting forms, i.e. {Rh(I)+ H+}, {Rh(II)+ H.}, and {Rh(III)+ H-}. A number of intermediates and oxidation states have been generated and explored in
Xiangyang Bi et al.
Journal of hazardous materials, 297, 191-197 (2015-05-11)
In this study, ground surface dust samples from two contrasting areas, a former zinc smelting area in Guizhou Province and a common urban district in Wuhan city, Hubei Province, China, were assessed for in vitro Pb bioaccessibility using a physiologically
Yang Yang et al.
Environmental science & technology, 48(20), 12362-12369 (2014-09-16)
Disinfectants inactivate pathogens in source water; however, they also react with organic matter and bromide/iodide to form disinfection byproducts (DBPs). Although only a few DBP classes have been systematically analyzed for toxicity, iodinated and brominated DBPs tend to be the
C Afonso et al.
Environmental research, 143(Pt B), 130-137 (2015-05-13)
The Se, Hg, and methylmercury (MeHg) levels in raw, cooked (boiled and grilled), and canned tuna (Thunnus spp.) were determined before and after an in vitro digestion, thereby enabling the calculation of the respective bioaccessibility percentages. A risk-benefit evaluation of
Jerzy Klosin et al.
Accounts of chemical research, 40(12), 1251-1259 (2007-11-14)
A series of bis-phosphite and bis-phosphine ligands for asymmetric hydroformylation reactions has been evaluated. Bis-phosphite ligands lead, in general, to high regioselectivities across a range of substrates while good enantioselectivities are limited to only a few examples. We found that
Raffaello Lazzaroni et al.
Chirality, 23(9), 730-735 (2011-08-23)
Indolizidine alkaloids have attracted considerable attention because of their vast array of structural diversity and varied biological activity. This article relates the results that we obtained in the field of the total synthesis of indolizidines from α-amino acids, based on
Stephen K Murphy et al.
Science (New York, N.Y.), 347(6217), 56-60 (2015-01-03)
The dehydroformylation of aldehydes to generate olefins occurs during the biosynthesis of various sterols, including cholesterol in humans. Here, we implement a synthetic version that features the transfer of a formyl group and hydride from an aldehyde substrate to a
Salah Al Zadjali et al.
International journal of clinical and experimental medicine, 8(5), 7160-7167 (2015-07-30)
Lead is a widely-spread environmental pollutant and a commonly-used industrial chemical that can cause multisystemic adverse health effects. However, the effects of lead exposure on diabetic animals have not been reported so far. The aim of this study is to
Vania B Rezende et al.
Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS), 29, 130-135 (2014-07-24)
Although a number of studies have measured circulating levels of some trace elements in preeclampsia (PE) and compared to healthy pregnant (HP), there is no consensus yet about the deficiency of some metals and development of hypertensive disorders in pregnancy.
The ONIOM Method and Its Applications.
Lung Wa Chung et al.
Chemical reviews, 115(12), 5678-5796 (2015-04-09)
Dipti Patel et al.
Dalton transactions (Cambridge, England : 2003), 44(31), 14159-14177 (2015-07-18)
Treatment of anhydrous FeX2 (X = Cl, Br, I) with one equivalent of bis(diphenylphosphino)ethane (dppe) in refluxing THF afforded analytically pure white (X = Cl), light green (X = Br), and yellow (X = I) [FeX2(dppe)]n (X = Cl, ;
María Garrido et al.
Chembiochem : a European journal of chemical biology, 16(4), 641-650 (2015-02-14)
Several diseases involve alterations in sphingolipid metabolism, so the development of tools for the analysis of sphingolipid metabolic fluxes is of interest. In this work, ω-azidosphingolipids 1-3 have been synthesized and tested as tracers in live cells. The synthesis starts
Vladimir V Grushin
Accounts of chemical research, 43(1), 160-171 (2009-10-01)
Although springing from two established fields, organometallic chemistry and fluorine chemistry, organometallic fluorine chemistry is still in its early stages. However, developments in this area are expected to provide new tools for the synthesis of selectively fluorinated organic compounds that
Nicolas P E Barry et al.
Chemical Society reviews, 41(8), 3264-3279 (2012-02-07)
This review describes how the incorporation of dicarba-closo-dodecarboranes into half-sandwich complexes of ruthenium, osmium, rhodium and iridium might lead to the development of a new class of compounds with applications in medicine. Such a combination not only has unexplored potential
Dong Jin Lee et al.
Angewandte Chemie (International ed. in English), 54(46), 13715-13718 (2015-09-18)
A new type of intermolecular rhodium(II)-catalyzed [5+3] cycloaddition has been developed. This higher-order cycloaddition between pyridinium zwitterion 1,5-dipole equivalents and enol diazoacetates enables the formation of eight-membered heterocyclic skeletons, which are otherwise difficult to construct. The optimized cycloaddition occurs efficiently under
Malene Outzen et al.
Nutrients, 7(1), 608-624 (2015-01-20)
Selenium status of the Danish population is below that assumed optimal for the suggested protective effects against chronic diseases, including certain cancers. Fish and shellfish are important dietary sources of selenium in Denmark. We investigated the effect of increased fish
Chumin Zhao et al.
Medical physics, 42(11), 6294-6308 (2015-11-02)
Large area x-ray imagers based on complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) technology have been proposed for various medical imaging applications including digital breast tomosynthesis (DBT). The low electronic noise (50-300 e-) of CMOS APS x-ray imagers provides a
D Sirbu et al.
Dalton transactions (Cambridge, England : 2003), 44(33), 14646-14655 (2015-07-28)
Copper(ii) and palladium(ii) meso-tetraferrocenylporphyrins ( and ) were employed as catalysts for electrochemical proton reduction in DMF using trifluoroacetic acid (TFA) or triethylamine hydrochloride (TEAHCl) as acids. Gas analysis under electrocatalytic conditions at a glassy carbon working electrode confirmed the
Xing-Zhong Shu et al.
Chemical Society reviews, 41(23), 7698-7711 (2012-08-17)
Transition metal-catalyzed acyloxy migration of propargylic esters offers versatile entries to allene and vinyl carbene intermediates for various fascinating subsequent transformations. Most π-acidic metals (e.g. gold and platinum) are capable of facilitating these acyloxy migration events. However, very few of
Jeremy M Praetorius et al.
Dalton transactions (Cambridge, England : 2003), (31)(31), 4079-4094 (2008-08-09)
The organometallic chemistry of N-heterocyclic carbene complexes of the transition metals has received significant attention over the past ten years, especially with respect to complexes of Pd and Ru. The present Perspective highlights the chemistry of NHC complexes of another
Anna V Vologzhanina et al.
Inorganic chemistry, 54(12), 5827-5838 (2015-05-29)
Template condensation of dichloroglyoxime with n-hexadecylboronic acid on the corresponding metal ion as a matrix under vigorous reaction conditions afforded n-hexadecylboron-capped iron and cobalt(II) hexachloroclathrochelates. The complexes obtained were characterized using elemental analysis, MALDI-TOF mass spectrometry, IR, UV-vis, (1)H and
I Haiduc et al.
In vivo (Athens, Greece), 3(4), 285-293 (1989-07-01)
Recent results on the antitumor activity of organometallic compounds of rhodium, iridium, copper and gold are reviewed. Coordination compounds of some organic ligands are also briefly mentioned. The most promising seem to be copper and gold complexes which exhibited remarkable
Guorong Sheng et al.
Organic letters, 16(19), 5096-5099 (2014-09-12)
3-Diazoindolin-2-imines were constructed from indoles and sulfonylazides via an electronically matched 1,3-dipolar cycloaddition and a subsequent dehydroaromatization/ring-opening cascade. The reaction between 3-substituted indoles and sulfonyl azides provided 2-aminoindoles, while 2-substituted indoles furnished 3-aminoindoles. Moreover, 2,3-diaminoindoles could be prepared from the
Angela Kaltenbach et al.
Analytical and bioanalytical chemistry, 407(11), 3093-3102 (2014-12-19)
Gravimetrically prepared mono-elemental reference solutions having a well-known mass fraction of approximately 1 g/kg (or a mass concentration of 1 g/L) define the very basis of virtually all measurements in inorganic analysis. Serving as the starting materials of all standard/calibration solutions, they
Kara Strickland et al.
Nature communications, 6, 7343-7343 (2015-06-11)
Replacement of noble metals in catalysts for cathodic oxygen reduction reaction with transition metals mostly create active sites based on a composite of nitrogen-coordinated transition metal in close concert with non-nitrogen-coordinated carbon-embedded metal atom clusters. Here we report a non-platinum
Rhodium-catalyzed C-C bond formation via heteroatom-directed C-H bond activation.
Denise A Colby et al.
Chemical reviews, 110(2), 624-655 (2009-05-15)
Kazuyuki Sato
Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan, 126(8), 597-605 (2006-08-02)
Novel fluoroalkylated products where a CF(2)COOEt group was introduced at the alpha-position of alpha,beta-unsaturated ketones or the Reformatsky-type products have been obtained selectively by the reaction of BrCF(2)COOEt and alpha,beta-unsaturated ketones with Et(2)Zn in the presence of RhCl(PPh(3))(3) depending on
Albert Padwa
Chemical Society reviews, 38(11), 3072-3081 (2009-10-23)
In this tutorial review, the rhodium(II)-catalyzed domino reactions of alpha-diazo carbonyl compounds are summarized. The article will emphasize some of the more recent synthetic applications of the rhodium carbenoid cyclization/cycloaddition domino cascade for alkaloid synthesis. The many structurally diverse and
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