Find your PDFs fast.
Welcome to the Pubget Medical Subject Headings (MESH) browser. Click on a topic or subtopic below to explore related papers. In the gold box is the most recent paper about the current MESH term, and below are 20 related papers.
Molecular Structure (6):
Recent article
Molecular Structure
Abstract
Two new crystal structures, calcium bis(hydrogen methylphosphonate), Ca(CH(3)PO(3)H)(2), and lithium hydrogen methylphosphonate, Li(CH(3)PO(3)H), have been obtained, and the experimental and theoretical charge densities, as well as their topological properties, are reported. Both compounds display la...
|
PMID: 21931209
PDF is available here.
PDF is available here.
| < More recent | Older article > |
Abstract
The combined study of electron-density features in three substituted hydropyrimidines of the Biginelli compound family has been fulfilled. Results of the low-temperature X-ray diffraction measurements and density functional theory (DFT) B3LYP/6-311++G** calculations of these compounds are described....
|
PMID: 21931212
PDF is available here.
PDF is available here.
Abstract
Covering: January 2007 to December 2009. Previous review: Nat. Prod. Rep., 2008, 25, 555-611.
|
PMID: 21845280
PDF is available here.
PDF is available here.
Organic Letters (13)18 2011
Abstract
Asymmetric vinylogous Mannich reaction (VMR) of 2-(tert-butyldimethylsilyloxy)furan (TBSOF, 1) with (R(S))- or (S(S))-t-BS-imines (3) furnished 5-aminoalkylbutenolides 7a-k in 75-87% yields with anti/syn ratios ranging from 75:25 to 97:3. Butenolides 7a-f,k were readily converted int...
|
PMID: 21854016
PDF is available here.
PDF is available here.
Biochimica et Biophysica Acta (1807)11 2011
Abstract
We analyzed the three major Chl-c pigments (Chl-c(1), c(2) and c(3)) in four phylogenetically distinct classes of Chl-c containing algae, i.e., heterokontophyta, dinophyta, cryptophyta and haptophyta using chiral HPLC. All the photosynthetic organisms contained only the (13(2)R)-enantiomerically pur...
|
PMID: 21806961
PDF is available here.
PDF is available here.
Abstract
Aryl phenyl ureas with a 4-quinazolinoxy substituent at the meta-position of the phenyl ring are potent inhibitors of mutant and wild type BRAF kinase. Compound 7 (1-(5-tert-butylisoxazol-3-yl)-3-(3-(6,7-dimethoxyquinazolin-4-yloxy)phenyl)urea hydrochloride) exhibits good pharmacokin...
|
PMID: 21807507
PDF is available here.
PDF is available here.
Abstract
Aryl phenyl ureas with a 4-quinazolinoxy substituent at the meta-position of the phenyl ring are potent inhibitors of mutant and wild type BRAF kinase. Compound 7 (1-(5-tert-butylisoxazol-3-yl)-3-(3-(6,7-dimethoxyquinazolin-4-yloxy)phenyl)urea hydrochloride) exhibits good pharmacokin...
|
PMID: 21807507
PDF is available here.
PDF is available here.
Abstract
Grassypeptolides F (1) and G (2), bis-thiazoline-containing cyclic depsipeptides with a rare β-amino acid, extensive N-methylation, and a large number of d-amino acids, are reported from an extract of the Palauan cyanobacterium Lyngbya majuscula. Both 1 and 2 were found to have moderate inhibitory a...
|
PMID: 21806011
PDF is available here.
PDF is available here.
Abstract
Two new grassypeptolides and a lyngbyastatin analogue, together with the known dolastatin 12, have been isolated from field collections and laboratory cultures of the marine cyanobacterium Leptolyngbya sp. collected from the SS Thistlegorm shipwreck in the Red Sea. The overall stereostructures of gra...
|
PMID: 21806012
PDF is available here.
PDF is available here.
Abstract
Six new secondary metabolites including two aphidicolin analogues, inflatins A (1) and B (2), and four chlamydosporol derivatives, inflatins C-F (3-6), have been isolated from the crude extract of Tolypocladium inflatum. The structures of 1-6 were determined mainly by NMR experiments, and 4 and 5 wer...
|
PMID: 21812410
PDF is available here.
PDF is available here.
Abstract
Swerilactones L-O (1-4), four unusual secoiridoids with unprecedented C₁₂ and C₁₃ skeletons, were isolated from the traditional Chinese herb Swertia mileensis. Compounds 1 and 2 had moderate inhibitory activities against the secretion of hepatitis B virus surface antigen (IC₅₀ = 1.47 and...
|
PMID: 21823575
PDF is available here.
PDF is available here.
Abstract
Eight new sesterterpenes (2, 5, and 10-15), including structurally related pentaprenyl hydroquinones (2 and 5), and seven known ones of the same structural classes were isolated from the sponge Coscinoderma sp., collected from Chuuk Island, Micronesia. On the basis of the results of combined spectros...
|
PMID: 21827183
PDF is available here.
PDF is available here.
Biochimica et Biophysica Acta (1808)10 2011
Abstract
These results show that CpOsm is a stable protein, and its antifungal activity involves membrane permeabilization, as property reported earlier for other osmotins and thaumatin-like proteins....
|
PMID: 21798235
PDF is available here.
PDF is available here.
Molecular BioSystems (7)9 2011
Abstract
PELDOR (pulsed electron-electron double resonance) spectroscopy was applied to determine spin-spin distances in spin-labeled DNA duplexes (13-mer and 17-mer) containing the damaged sites 8-oxoguanine or uncleavable abasic site analogue tetrahydrofuran. The lesions were located in one...
|
PMID: 21731955
PDF is available here.
PDF is available here.
Abstract
Antimicrobial properties of medicinal plants and plant parts such as flowers, roots, fruits, seeds and oils are being used to cure some chronic and acute diseases throughout the world. In the present study, an attempt has been made to isolate and identify the antibacterial compound p...
|
PMID: 22013726
PDF is available here.
PDF is available here.
Biocontrol Science (16)3 2011
Abstract
The effect of sodium hypochlorite (NaOCl) on the decolorization of azo dye orange II (4-[(2-hydroxy-1-naphthalenyl) azo]-benzenesulfonic acid, monosodium salt) in aqueous solution was studied as a function of pH. The first-order rate constant of color reduction (k) was evaluated from...
|
PMID: 21946323
PDF is available here.
PDF is available here.
Abstract
Photophysical properties of a natural plant alkaloid, ellipticine (5,11-dimethyl-6H-pyrido[4,3-b]carbazole), which comprises both proton donating and accepting sites, have been studied in different solvents using steady state and time-resolved fluorescence techniques primarily to understand the origi...
|
PMID: 21812494
PDF is available here.
PDF is available here.
Abstract
We present a data mining approach that enables the identification of alternative analog series with different core structures, corresponding substitution patterns, and comparable potency progression. Scaffolds can be exchanged between these series and new analogs suggested that incorporate preferred...
|
PMID: 21774471
PDF is available here.
PDF is available here.
Abstract
We present an extension of the activity cliff concept by introducing "activity ridges" that are formed by overlapping "combinatorial" activity cliffs between participating compounds, giving rise to ridge-like structures in activity landscapes. Activity ridges are rich in SAR information. In a system...
|
PMID: 21761918
PDF is available here.
PDF is available here.
Abstract
Abstract
A large-scale similarity search investigation has been carried out on 266 well-defined compound activity classes extracted from the ChEMBL database. The analysis was performed using two widely applied two-dimensional (2D) fingerprints that mark opposite ends of the current performanc...
|
PMID: 21728295
PDF is available here.
PDF is available here.
Abstract
We report here the rational synthesis of a [Mn(3)CaO(4)](6+) cubane that structurally models the trimanganese-calcium-cubane subsite of the OEC. Structural and electrochemical comparison between Mn(3)CaO(4) and a related Mn(4)O(4) cubane alongside characterization of an intermediate calcium-manganes...
|
PMID: 21817047
PDF is available here.
PDF is available here.
Abstract
The electronic and structural properties of pyrrolic ring derivatives were studied using density functional theory (DFT) in terms of their application as organic semiconductor materials in photovoltaic devices. The B3LYP hybrid functional in combination with Pople type 6-31G(d) basis...
|
PMID: 21120557
PDF is available here.
PDF is available here.
Abstract
An all-electron scalar relativistic calculation was performed on Au( n )H(2)O (n = 1-13) clusters using density functional theory (DFT) with the generalized gradient approximation at PW91 level. The calculation results reveal that, after adsorption, the small gold cluster would l...
|
PMID: 21140279
PDF is available here.
PDF is available here.
Abstract
In this research, electric field gradient (EFG), which is the first derivative of electric field, is applied for evaluation of aromaticity of 89 cyclic organic compounds. In our calculations, DFT procedure (b3lyp) with basis set 6-311++G** has been employed, and the obtained electron...
|
PMID: 21153907
PDF is available here.
PDF is available here.
Abstract
Our findings are in accordance with previously reported results obtained from the kinetic studies of the binding of acridine and related tricyclic carboxamides to DNA....
|
PMID: 21153908
PDF is available here.
PDF is available here.
Abstract
Stacking interactions of phenanthroline square-planar complexes in crystal structures were studied by analyzing data from the Cambridge Structural Database. In most of the crystal structures, two phenanthroline complexes were oriented "head to tail." Phenanthroline complexes show a w...
|
PMID: 21161558
PDF is available here.
PDF is available here.
Abstract
First-principles calculations were performed for fluorine-decorated graphene (fluorographene). Three different hexagonal clusters were used-circular (C(24)H(12)), triangular (C(23)H(10)) and rectangular (C(24)H(12))-and the fluorine atoms were randomly distributed in the mesh. Graphe...
|
PMID: 21161668
PDF is available here.
PDF is available here.
Abstract
Seventy-five 1,5,6,7-tetrahydro-pyrrolo[3,2-C]pyridinone derivatives displaying potent activities against Cdc7 kinase were selected to establish 3D-QSAR models using CoMFA and CoMSIA methods. Internal and external cross-validation techniques were investigated as well as some measures...
|
PMID: 21416222
PDF is available here.
PDF is available here.
Abstract
Abstract
N-Cyclohexyl-3-methoxyquinoxalin-2-carboxamide (QCM-13), a novel 5-HT3 antagonist identified from a series of compounds with higher pA2 (7.6) and good log P (2.91) value was screened in rodent models of depression such as forced swim test (FST), tail suspension test (TST), interactio...
|
PMID: 21870430
PDF is available here.
PDF is available here.
Abstract
We have designed and developed a one-pot synthesis of deoxyribonucleoside 5'-triphosphates without any protection on the nucleosides. A facile synthesis is achieved by generating an in situ phosphitylating reagent that reacts selectively with the 5'-hydroxyl groups of the unprotected nucleosides. Th...
|
PMID: 21790120
PDF is available here.
PDF is available here.
Abstract
The synthesis of a new kinase inhibitor template 2-anilino-7-aryl-pyrrolo[2,1-f][1,2,4]triazine is described which includes a late stage orthogonally reactive key intermediate amenable to rapid diversification as well an optimized in situ triflate displacement to install the C2-anili...
|
PMID: 21790122
PDF is available here.
PDF is available here.
Abstract
A simple protocol is reported for the preparation of primary aryl amides under Pd-catalyzed carbonylation chemistry applying a two-chamber system with crystalline and nontransition metal based sources of carbon monoxide and ammonia. The method is suitable for the synthesis of a numbe...
|
PMID: 21790124
PDF is available here.
PDF is available here.
Abstract
A novel and efficient route for the synthesis of 2-amino-H-pyrazolo[5,1-a]isoquinolines via a three-component reaction of N'-(2-alkynylbenzylidene)hydrazide, alkyne, and sulfonyl azide is described. This transformation, co-catalyzed by silver triflate and copper(I) bromide under mild...
|
PMID: 21790168
PDF is available here.
PDF is available here.
Abstract
An efficient method for a Pd(OAc)(2)-catalyzed cross-coupling reaction of glycals with activated alkenes under mild conditions has been developed. This transformation provides an expedient synthetic method to C(2)-functionalized glycals, which are common structural building blocks in...
|
PMID: 21793496
PDF is available here.
PDF is available here.
Abstract
A rhodium-catalyzed oxidative acylation of benzamides with aryl aldehydes via direct sp(2) C-H bond cleavage is described. In the presence of [Cp*RhCl(2)](2), AgSbF(6), and silver carbonate as an oxidant, N,N-diethyl benzamides can be effectively carbonylated to yield ortho-acyl benz...
|
PMID: 21793534
PDF is available here.
PDF is available here.
Abstract
An efficient synthesis of chloroisosulochrin was accomplished using a novel ortho-selective chlorination of a phenol with sulfuryl chloride and 2,2,6,6-tetramethylpiperidine as the key step. Further elaboration by a biomimetic route converted chloroisosulochrin to dihydromaldoxin, ma...
|
PMID: 21793536
PDF is available here.
PDF is available here.
Abstract
The activation of N-alkyl prolinols by XtalFluor E allowed the formation of an aziridinium intermediate that can react with tetrabutylammonium azide (nBu(4)NN(3)) to produce 3-azidopiperidines and/or 2-(azidomethyl)pyrrolidines, in a ratio up to 100/0. These 3-azidopiperidines can be...
|
PMID: 21793544
PDF is available here.
PDF is available here.
Abstract
A short and highly modular three-step synthesis of a new class of substituted naphthothiophenes has been developed exploiting a Pd-catalyzed tandem direct arylation/Suzuki coupling transformation as the key step.
|
PMID: 21793545
PDF is available here.
PDF is available here.
Abstract
Enantioselective formal synthesis of macrolactone palmerolide A, a polyketide marine natural product, is described. Key strategies in the synthesis include the oxidative furan ring-opening of a chiral furyl carbinol for the installation of the 1,4-dienol core and a Jung nonaldol-aldo...
|
PMID: 21793548
PDF is available here.
PDF is available here.
Abstract
Our synthesis features preparation of a pseudosymmetrical dienyne through chirality transfer from an allenylsilane, a dienyne metathesis to produce the bicyclo [5.4.0] system in optically active form, selective functionalization of a diene via a 5-exo-trig iodoetherification, and an asymmetric propa...
|
PMID: 21793562
PDF is available here.
PDF is available here.
Abstract
A new efficient method for the direct alkenylation of chromones via a palladium(II)-catalyzed C-H functionalization reaction was developed. The use of pivalic acid with Cu(OAc)(3)/Ag(2)CO(3) provided superior reactivity in the cross-coupling of chromones with alkene partners. This ap...
|
PMID: 21797199
PDF is available here.
PDF is available here.
Abstract
Starting with commercial reagents, bicyclic 1,2,3-triazolium ionic liquids [b-3C-tr][NTf(2)] (1) and [b-4C-tr][NTf(2)] (2) were synthesized in four steps with high overall isolated yields of 68% and 76%, respectively. Since the C-5 hydrogen is acidic, under basic condition ionic liqu...
|
PMID: 21797204
PDF is available here.
PDF is available here.
Abstract
Metal-ligand complexes of Cu(OTf)(2) with an appropriate bisphosphine ligand have been shown to effectively catalyze the formation of substituted tetrahydropyrans via a sequential olefin migration and Prins-type cyclization. This methodology provides convenient access to a variety of...
|
PMID: 21797234
PDF is available here.
PDF is available here.
Abstract
Silyl-protected (R)-methyl 2-(hydroxymethyl)butanoate was obtained by an enantioselective Ir-catalyzed hydrogenation in high yield and selectivity. Elaboration of this building block via Takai and Stille reactions gave a protected hydroxy polyene chain, which was coupled to a 5-hydro...
|
PMID: 21797235
PDF is available here.
PDF is available here.
Abstract
A palladium-catalyzed (3 + 2) cycloaddition of a vinylcyclopropane and a β-nitrostyrene is employed to rapidly assemble the cyclopentane core of the Melodinus alkaloids. The ABCD ring system of the natural product family is prepared in six steps from commercially available materials...
|
PMID: 21786746
PDF is available here.
PDF is available here.
Abstract
An enantioselective and diastereoselective aza-[3 + 3] annulation of pyrrolidine-based exo-cyclic vinylogous amides and urethanes with chiral vinyl iminium salts is described. This asymmetric annulation manifold is possible because of an unexpected regiochemical reversal whereby head...
|
PMID: 21786757
PDF is available here.
PDF is available here.
Abstract
8-Hydroxyquinolin-N-oxide was found to be a very efficient ligand for the copper-catalyzed hydroxylation of aryl iodides, aryl bromides, or aryl chlorides under mild reaction conditions. This methodology provides a direct transformation of aryl halides to phenols and to alkyl aryl et...
|
PMID: 21786767
PDF is available here.
PDF is available here.
Abstract
The application of chiral sulfinamides and achiral sulfonic acids as a cocatalyst system for enantioselective protonation reactions is described. Structurally simple, easily accessible sulfinamides were found to induce moderate-to-high ee's in the formation of 2-aryl-substituted cycl...
|
PMID: 21786775
PDF is available here.
PDF is available here.
Abstract
Two sets of conditions have been developed for a base-mediated, transition-metal-free alkynylation of aryl chlorides that proceeds via benzyne intermediates. The first set of conditions involves the use of TMPLi base in a pentane/THF mixture at 25 °C. The second set involves use of...
|
PMID: 21786825
PDF is available here.
PDF is available here.
Abstract
The first asymmetric sulfa-Michael addition of thiols to 4,4,4-trifluorocrotonates for the construction of a stereogenic center bearing a unique trifluoromethyl group and a sulfur atom has been achieved in high yields and excellent enantioselectivities with a 1 mol % bifunctional org...
|
PMID: 21786836
PDF is available here.
PDF is available here.
Abstract
Deconvolution of the role of off-cycle species from the desired catalytic cycle leads to an optimized protocol for the prolinate-catalyzed amination of aldehydes. The scope of complex reaction networks will be greatly broadened by understanding ancillary rate processes that influence...
|
PMID: 21761822
PDF is available here.
PDF is available here.
Abstract
An efficient palladium(0)-catalyzed, Cu(I)-mediated synthetic route to trisubstituted olefins and conjugate dienes has been developed via oxo directing Liebeskind-Srogl cross-coupling reactions of gem-dihaloolefin-type α-oxo ketene dithioacetals with aryl and alkenylboronic acids. T...
|
PMID: 21761823
PDF is available here.
PDF is available here.
Abstract
A new hydrative cyclization of 1,7- and 1,8-diynyl ethers is reported. Using catalytic InI(3) and p-TSA as a cocatalyst, several 2,2-disubstituted tetrahydrofurans with exocyclic enone appendages were prepared. Reaction optimization and scope, mechanistic insight, and further transfo...
|
PMID: 21761825
PDF is available here.
PDF is available here.
Abstract
A highly convergent synthesis of the pyridine core of the thiopeptide antibiotic cyclothiazomycin has been developed based on a [2 + 2 + 2] cyclotrimerization key step. The regioselective assembly of the heterocyclic center of this important class of antibiotics takes advantage of a...
|
PMID: 21761830
PDF is available here.
PDF is available here.
Abstract
Attachment of H(2)O(2) onto the highly hindered quaternary C-12a in an advanced qinghaosu (artemisinin) precursor has been achieved through a facile perhydrolysis of a spiro epoxy ring with the aid of a previously unknown molybdenum species without involving any special equipment or...
|
PMID: 21761857
PDF is available here.
PDF is available here.
Abstract
An efficient synthetic methodology was developed to assemble 1-azaanthraquinones from N-propargylaminoquinones by copper(II)-promoted sequential 6-endo-dig chlorocyclization and oxidative aromatization. The approach can be extended to preprare chlorinated alkaloids such as cleistophi...
|
PMID: 21766780
PDF is available here.
PDF is available here.
Abstract
An aldol reaction followed by elimination of the derived mesylate was used to construct the side chain that was designed to afford the cyclohexene ring of coronafacic acid via intramolecular alkylation. Elimination of the mesylate proceeded with TBAF. The alkylation was achieved with...
|
PMID: 21766797
PDF is available here.
PDF is available here.
Abstract
Phospholipids bearing tetrafluorophenylazido chromophores were synthesized with perfectly conserved amphiphilicity and photochemical activity. Interestingly however, those phospholipids harboring the amine-linked chromophores exhibited unusual (19)F NMR signals which depended on the...
|
PMID: 21766799
PDF is available here.
PDF is available here.