bluuebunny/crossref_metadata_2025 huggingface dataset:
Antiprotozoal, Schistosomicidal, and Antimicrobial Activities of the Essential Oil from the Leaves of Baccharis dracunculifolia
Authors: Parreira Natállia A. , Magalhães Lizandra G. , Morais Denis R. , Caixeta Soraya C. , de Sousa João P. B. , Bastos Jairo K. , Cunha Wilson R. , Silva Márcio L. A. , Nanayakkara N. P. D. , Rodrigues Vanderlei , da Silva Filho Ademar A.
Published: April 2010

Baccharis dracunculifolia DC. (Asteraceae), popularly known as ‘alecrim do campo’, is a native plant from Brazil used in folk medicine as febrifuge, anti‐inflammatory, antiseptic, and to treat skin sores. Also, B. dracunculifolia is the most important plant source of the Brazilian green propolis, which is recognized for its antiseptic and antiprotozoal activities. This study aimed at investigating the in vitro antiprotozoal, schistosomicidal, and antimicrobial activities of the essential oil from the leaves of B. dracunculifolia. The essential oil was obtained by hydrodistillation and analyzed by GC and GC/MS, which allowed the identification of 14 compounds, mainly oxygenated sesquiterpenes, such as (E)‐nerolidol (33.51%) and spathulenol (16.24%). The essential oil showed activity against promastigote forms of Leishmania donovani, with IC50 values of 42 μg/ml. The essential oil displayed high activity in the schistosomicidal assay, since all pairs of Schistosoma mansoni adult worms were dead after incubation with the essential oil (10, 50, and 100 μg/ml). B. dracunculifolia essential oil was neither cytotoxic against Vero cells, nor active in the antimicrobial and antiplasmodial assays.
Composition and Chemical Variability of Mentha suaveolens ssp. suaveolens and M. suaveolens ssp. insularis from Corsica
Authors: Sutour Sylvain , Bradesi Pascale , Casanova Joseph , Tomi Félix
Published: April 2010

A detailed analysis of two essential oils from individual plants of Mentha suaveolens ssp. suaveolens growing wild in Corsica was carried out by combination of GC(RI), GC/MS, and 13C‐NMR analyses. One oil sample is characterized by the pre‐eminence of piperitenone oxide, and the second is dominated by piperitenone. In contrast, it was reported that the essential oil of M. suaveolens ssp. insularis, an endemic species to Corsica and Sardinia, contained pulegone and cis‐cis‐p‐menthenolide as main components. A principal‐component analysis (PCA) carried out on the composition of the essential oil of 59 individual plants of M. suaveolens sp. allowed the classification into three well‐defined groups. All the oil samples from Mentha suaveolens ssp. insularis belonged to the same group, while the oils from M. suaveolens ssp. suaveolens were distributed in the two other groups. The composition of the essential oil isolated from aerial parts of M. suaveolens ssp. has been shown to be an additional tool to differentiate the botanically close subspecies suaveolens and insularis.
The Future of Aminoglycosides: The End or Renaissance?
Authors: Houghton Jacob L. , Green Keith D. , Chen Wenjing , Garneau‐Tsodikova Sylvie
Published: April 2010

Although aminoglycosides have been used as antibacterials for decades, their use has been hindered by their inherent toxicity and the resistance that has emerged to these compounds. It seems that such issues have relegated a formerly front‐line class of antimicrobials to the proverbial back shelf. However, recent advances have demonstrated that novel aminoglycosides have a potential to overcome resistance as well as to be used to treat HIV‐1 and even human genetic disorders, with abrogated toxicity. It is not the end for aminoglycosides, but rather, the challenges faced by researchers have led to ingenuity and a change in how we view this class of compounds, a renaissance.
Simultaneous 19F NMR Screening of Prolyl Oligopeptidase and Dipeptidyl Peptidase IV Inhibitors
Authors: Kichik Nessim , Tarragó Teresa , Giralt Ernest
Published: April 2010

Prolyl oligopeptidase (POP) and dipeptidyl peptidase IV (DPP IV) are serine proteases that belong to the same family of enzymes. These peptidases are relevant because of their association with the pathophysiology of serious illnesses, such as type 2 diabetes (DPP IV), and those related to cognitive disorders (POP). Several NMR‐based screening methods are being used to find and validate new hit scaffolds. In particular, 19F NMR‐based screening methods have proven to be powerful tools for the discovery and development of new inhibitors. Here we present an accurate and reliable 19F NMR‐based simultaneous assay that is used to screen for new selective POP and DPP IV inhibitors in compound mixtures. This activity assay consists of the simultaneous performance of POP and DPP‐IV 19F NMR activity assays in the presence of their fluorine‐containing substrates. Furthermore, the assays were conducted in the presence of 0.01 % v/v of Triton X‐100, which is a detergent that disrupts micelle formation, thereby preventing unspecific aggregate‐based inhibition. Finally, this 19F NMR methodology was applied to screen for ligands in plant extracts. Our results indicate that this method allows the simultaneous and accurate identification of selective POP and DPP IV inhibitors in these compound mixtures.
Giant splenic artery aneurysm: Managed in the cardiovascular catheterization laboratory using the modified neck remodeling technique
Authors: Pappy Reji , Sech Candice , Hennebry Thomas A.
Published: April 2010

We report the first case of coil embolization using the “modified neck remodeling technique” in the management of a splenic artery aneurysm. This technique was feasible due to the unique and complex anatomy of the aneurysm. This condition has been largely treated by vascular surgeons and interventional radiologists; however, this patient was referred to the interventional cardiologists for endovascular coiling. © 2010 Wiley‐Liss, Inc.
Occlusion of Sano conduit with the Amplatzer Vascular Plug: A reliable method for staged elimination of accessory pulmonary blood flow in single ventricle palliation
Authors: Gordon Brent M. , Hashmi Aijaz , Kuhn Micheal A.
Published: April 2010

Background: Staged palliative surgery is often required to regulate pulmonary and systemic blood flow in children with complex congenital heart disease. Accessory sources of pulmonary blood flow have been utilized to provide satisfactory pulmonary blood flow after Glenn anastomosis in select patients. Prolonged exposure to increased flow can lead to elevated pulmonary arterial pressures and volume loading of the ventricle, potentially limiting candidacy for Fontan completion. Objective: To review the feasibility, technique, and outcome of transcatheter closure of the Sano conduit utilizing the Amplatzer Vascular Plug (AVP). Methods: All patients who underwent device closure of the Sano conduit with an AVP were reviewed retrospectively. Patient demographics, indications, procedural details, and patient outcomes were reviewed. Hemodynamic changes before and after occlusion of the Sano conduit were compared. A P value < 0.05 was considered significant. Results: Between 2005 and 2009, 11 male patients underwent Sano occlusion with an AVP. Average weight was 8.8 ± 2.2 kg. The Sano was occluded from both antegrade (n = 6) and retrograde (n = 5) approaches. Arterial saturation and mean pulmonary artery pressure both decreased significantly after Sano occlusion [86.9 ± 4.9% to 82.6 ± 4.9% (P < 0.001) and 14.1 ± 5 mm Hg to 12.8 ± 4 mm Hg (P < 0.05), respectively]. Conduit diameter averaged 3.6 mm (range 3.1–4.4) 13 months after Stage I palliation. The conduit was closed using a 6 mm AVP in nine patients and a 4 mm AVP in the other two. The ratio of AVP size to conduit diameter was 1.5 ± 0.27. There were no procedural complications and all patients at least 2 years of age have undergone Fontan completion. Conclusions: The Sano conduit can be left open in select patients who do not tolerate closure after Glenn anastomosis. It can be closed safely and effectively using the AVP. © 2010 Wiley‐Liss, Inc.
Improving myocardial salvage in late presentation acute ST‐elevation myocardial infarction with proximal embolic protection
Authors: Larose Eric , Tizon‐Marcos Helena , Rodés‐Cabau Josep , Rinfret Stéphane , Déry Jean‐Pierre , Nguyen Can M. , Gleeton Onil , Boudreault Jean‐Rock , Roy Louis , Noël Bernard , Proulx Guy , Rouleau Jacques , Barbeau Gérald , De Larochellière Robert , Bertrand Olivier F.
Published: April 2010

Background: Late‐presenting ST‐elevation myocardial infarction (STEMI) patients possess larger, more organized coronary thrombus leading to greater ventricular remodeling and arrhythmia despite angioplasty and pharmacological therapies. We hypothesized that myocardial injury would be reduced in late STEMI by proximal embolic protection (PEP). Methods: 31 patients with first STEMI 12–24 hr after pain onset and TIMI 0–1 flow were treated with or without PEP (cohort design matched for age, gender, and infarct‐related artery). Contrast‐enhanced magnetic resonance determined myocardial function, area at risk, necrosis, salvaged myocardium, and arrythmogenic peri‐infarct region. Clinical follow‐up was performed. Results: Pain to balloon time was 18 hr (95% CI 15.5–21.2 h), and Q waves were present in 87%. Angioplasty was performed with PEP in 15 and without in 16. Left ventricular (LV) volumes and ejection fraction were similar (EF 46.9% vs. 49.0% without PEP, P = 0.9). Although myocardial necrosis was similar (32.5 vs. 37.3% of LV, P = 0.3), PEP improved microvascular obstruction (8.7 vs. 11.2% of LV, P = 0.02) salvaged myocardium (39.6% vs. 29.6% of area at risk, P = 0.001), and the peri‐infarct region (20.9 vs. 29.6% of infarct, P < 0.0001). On multivariate analysis, the use of PEP was an independent predictor of decreased arrythmogenic peri‐infarct region and greater myocardial salvage. Conclusion: In this pilot study, PEP improved myocardial salvage and the arrythmogenic peri‐infarct region in late‐presentation STEMI. Randomized trials are required to assess the clinical impact of improving salvaged myocardium and the peri‐infarct region with PEP. © 2010 Wiley‐Liss, Inc.
Cardiac catheterization in patients with end‐stage liver disease: Safety and outcomes
Authors: Pillarisetti Jayasree , Patel Pavan , Duthuluru Sowjanya , Roberts Jenny , Chen Warren , Genton Randall , Wiley Mark , Candipan Robert , Tadros Peter , Gupta Kamal
Published: April 2010

Introduction: Patients with end‐stage liver disease (ESLD) awaiting transplant are at increased risk of bleeding. Nevertheless, these patients routinely undergo cardiac catheterization for various indications. Safety and outcomes of cardiac catheterization in these patients are not well reported. Methods: In a case–control study 43 patients with ESLD who underwent angiography for liver transplant work‐up were compared to 43 age and gender‐matched controls with no liver dysfunction. In‐hospital outcomes and procedural variables were compared. Results: Patients with ESLD had a lower baseline hemoglobin (12.1 ± 2.1 vs. 13.7 ± 1.8, P < 0.0005), lower platelet counts (86.8 ± 66 vs. 247 ± 80, P < 0.0001) and higher international normalized ratio (INR) (1.4 ± 0.2 vs. 1.1 ± 0.2, P < 0.0001) than controls. Among ESLD group, five (11.6%) patients received platelet transfusions, one received blood transfusion, and three patients (7%) with INR > 1.6 received fresh frozen plasma (FFP) compared with none in the control group. Smaller size (four French) vascular sheaths were used more frequently in the group with ESLD (16% vs. 4%, P = 0.04). There were no significant vascular or bleeding complications in either group. Conclusions: Elective cardiac catheterization can be safely performed in patients with ESLD with outcomes (vascular and bleeding complications, length of hospital stay and in‐hospital mortality) similar to patients without liver disease despite significant thrombocytopenia and elevated INR in patients with ESLD. Practices such as platelet transfusion for platelets <60,000 μL, prophylactic FFP transfusion for INR ≥≥ 1.6, less frequent use of antiplatelet therapy and more frequent use of smaller vascular sheaths may have contributed to the safety of cardiac catheterization in ESLD patients. © 2010 Wiley‐Liss, Inc.
First‐in‐man use of a tapered endovascular stent graft for treatment of aneurysm after coarctation repair
Authors: Nietlispach Fabian , Leipsic Jonathon , Wijesinghe Namal , Webb John G. , Carere Ronald G.
Published: April 2010

Objectives: Endovascular stenting of aneurysms late after surgical repair of coarctation may have to deal with marked changes in aortic diameter proximal and distal to the aneurysm. We report our first‐in‐man successful use of a custom‐made tapered (variable diameter) covered stent. Methods: The aneurysm was 42 mm in diameter with a length of 40 mm. On MRI, the aorta measured 19.6 mm proximal and 13.3 mm distal to the aneurysm. The aim was to oversize the stent by 10–20%. A covered Cheatham‐platinum stent was designed so that cranial portion of the stent would expand to 22 mm and the caudal portion to 15 mm with a length of 8.5 cm when fully inflated. The stent was mounted on a balloon‐in‐balloon delivery system and was delivered through an 18 F femoral arterial sheath. Rapid‐pacing technique was used for deployment. Results: The stent was successfully deployed without complications. After deployment, the stent diameter measured 21.2 mm cranially and 15.6 mm caudally. A mild distal endoleak due to inadequate fixation of the stent graft was resolved by post dilation expanding the stent diameter to 22.1 mm and 15.9 mm, respectively. The femoral access site was closed using two percutaneous closure devices and the patient discharged the day after the procedure. Follow‐up CT‐angiography showed continued successful exclusion of the aneurysm. Conclusions: A new custom‐made balloon expandable covered stent‐design enabled successful treatment of an aortic aneurysm. This design may offer greater potential for more favorable initial angiographic results and potentially long‐term outcomes due to superior apposition to the aortic wall. © 2010 Wiley‐Liss, Inc.
Management of implant failure during transcatheter aortic valve implantation
Authors: Ussia Gian Paolo , Barbanti Marco , Immè Sebastiano , Scarabelli Marilena , Mulè Massimiliano , Cammalleri Valeria , Aruta Patrizia , Pistritto Anna Maria , Capodanno Davide , Deste Wanda , Di Pasqua Maria Concetta , Tamburino Corrado
Published: April 2010

Background: Transcatheter aortic valve implantation (TAVI) is an emerging alternative to palliative medical therapy for nonsurgical patients with severe aortic stenosis. There is a paucity of detailed data on the management and outcome of complications related to the sub‐optimal deployment of the prosthesis. We appraised the incidence and management of early implant failure occurring during TAVI. Methods: Of 110 patients who underwent TAVI using the third generation 18‐French CoreValve ReValving System (Medtronic, MN) in our Institution between June 2007 and January 2010, we identified those experiencing early implant failure and reported on their management and clinical outcome. The primary endpoint was the incidence of major adverse cardiovascular and cerebrovascular event (MACCE) at 30 days and mid‐term follow up. Results: Early implant failure occurred in 18 of 110 patients (16.3%). The most common cause was prosthesis under‐expansion conditioning moderate to severe peri‐valvular leak (44.4%). Prosthesis deployment too low or too high with respect to the aortic annulus leading to severe peri‐valvular leak occurred in 22.2% and 5.5% of patients, respectively. Need of valve retrieve after the first attempt of deployment occurred in four cases (22.2%). Prosthesis embolization in the ascending aorta occurred in 5.5% of patients who experienced early implant failure. All implant failure cases were managed percutaneously with gain in aortic valve area from 0.44 ± 0.17 to 1.28 ± 0.27 cm2 (P < 0.001), decrease of mean transaortic gradient from 55.00 ± 19.51 to 11.58 ± 5.91 mmHg (P < 0.001) and no MACCE at 30 days. After 11 ± 6 months, MACCE occurred cumulatively in two patients (11.1%). Conclusions: Early implant failure can complicate the TAVI procedure with the CoreValve system, but it can be managed safely and effectively with bailout transcatheter techniques, avoiding surgery, with good early and mid‐term clinical and echocardiographic results. © 2010 Wiley‐Liss, Inc.
Chemoselective Hydrogenolysis of Tetrahydropyran‐2‐methanol to 1,6‐Hexanediol over Rhenium‐Modified Carbon‐Supported Rhodium Catalysts
Authors: Chen Kaiyou , Koso Shuichi , Kubota Takeshi , Nakagawa Yoshinao , Tomishige Keiichi
Published: April 2010

Modification of Rh/C with Re species enabled chemoselective hydrogenolysis of tetrahydropyran‐2‐methanol to 1,6‐hexanediol. In particular, the Rh–ReOx/C (Re/Rh ratio=0.25) catalyst gave a high yield of 1,6‐hexanediol (84 %) and showed a very low activity for overhydrogenolysis to 1‐hexanol. Using the same catalyst in the hydrogenolysis of tetrahydrofurfuryl alcohol also gave a high yield of 1,5‐pentanediol (94 %). Characterization results indicate the formation of ReOx clusters attached on the surface of Rh metal particles. This can cause the synergy between ReOx and Rh, and the tetrahydropyran‐2‐methanol hydrogenolysis proceeds on the interface between Rh metal surface and attached ReOx species.
Minimal Hydrolases: Organocatalytic Ring‐Opening Polymerizations Catalyzed by Naturally Occurring Carboxylic Acids.
Authors: Domínguez de María Pablo
Published: April 2010

Organocatalysis has emerged during the last decade as a concept with a significant number of synthetic applications. Important driving forces for this growth are that organocatalytic strategies often operate at rather mild reaction conditions, with reduced waste formation, and that processes may lead to high selectivities. In this area, some organocatalytic examples have been reported in the field of ring‐opening polymerizations of lactones, as well as for some (trans)esterifications. These reactions are catalyzed by organic molecules such as α‐hydroxycarboxylic acids, amino acids, 4‐(dimethylamino)pyridine, N‐heterocyclic carbenes, guanidines, or bifunctional thiourea–amines. With regard to α‐hydroxycarboxylic acids, it is believed that these organocatalysts catalyze reactions in a similar fashion to hydrolases, such as lipases or esterases, thus leading to valuable biomimetic catalytic concepts. Importantly, advantages that are inherent to enzymatic catalysis can be combined with a broader range of potential reaction conditions (e.g., solvent‐free), or exploited for the efficient and selective (tailored) modification of synthetically challenging substrates (e.g., ring‐opening polymerizations with cellulose and other polysaccharides as initiators). Furthermore, α‐hydroxycarboxylic acids are readily accessible by biotechnological routes such as fermentation, are nontoxic, and easy to apply. Herein, the uses of these “minimal hydrolases” in catalyzing ring‐opening polymerizations and transesterifications are categorized and discussed. Albeit still at the level of proof‐of‐principle, many interesting practical applications can be conducted according to these biomimetic routes.
Deconvolution of femtosecond time‐resolved spectroscopy data in multivariate curve resolution. Application to the characterization of ultrafast photo‐induced intramolecular proton transfer
Authors: Mouton Nicolas , Sliwa Michel , Buntinx Guy , Ruckebusch Cyril
Published: April 2010

In femtosecond absorption spectroscopy, deconvolution of the measured kinetic traces is still an important issue as photochemical processes that may possess shorter characteristic times than the time resolution of the experiment are usually considered. In this work, we propose to perform deconvolution of the time‐dependent concentration profiles extracted from multivariate curve resolution (MCR) applied to spectrokinetic data. The profiles are fitted with a model function including a description of the instrumental response function (IRF) of the experiment. The method combines the potential benefits of soft‐modeling data analysis with the ones of hard‐modeling for parameter estimation. The potential of the method is demonstrated first analyzing five synthetic data sets for which IRF of different widths are simulated. It is then successfully applied to resolve femtosecond UV‐visible transient absorption spectroscopy data investigating the photodynamics of salicylidene aniline, a photochromic molecule of wide interest. Considering a time resolution of 150 fs for the IRF, a characteristic time of 45 fs is recovered for the first step of the photo‐induced process which consists of an ultrafast intramolecular proton transfer. Our results also confirm the existence of an intermediate species with a characteristic time of 240 fs. Copyright © 2010 John Wiley & Sons, Ltd.
Borane and Borohydride Complexes of the Rare‐Earth Elements: Synthesis, Structures, and Butadiene Polymerization Catalysis
Authors: Jenter Jelena , Meyer Nils , Roesky Peter W. , Thiele Sven K.‐H. , Eickerling Georg , Scherer Wolfgang
Published: April 2010

The reaction of potassium 2,5‐bis[N‐(2,6‐diisopropylphenyl)iminomethyl]pyrrolyl [(dip2‐pyr)K] with the borohydrides of the larger rare‐earth metals, [Ln(BH4)3(thf)3] (Ln=La, Nd), afforded the expected products [Ln(BH4)2(dip2‐pyr)(thf)2]. As usual, the trisborohydrides reacted like pseudohalide compounds forming KBH4 as a by‐product. To compare the reactivity with the analogous halides, the dimeric neodymium complex [NdCl2(dip2‐pyr)(thf)]2 was prepared by reaction of [(dip2‐pyr)K] with anhydrous NdCl3. Reaction of [(dip2‐pyr)K] with the borohydrides of the smaller rare‐earth metals, [Sc(BH4)3(thf)2] and [Lu(BH4)3(thf)3], resulted in a redox reaction of the BH4− group with one of the Schiff base functions of the ligand. In the resulting products, [Ln(BH4){(dip)(dip‐BH3)‐pyr}(thf)2] (Ln=Sc, Lu), a dinegatively charged ligand with a new amido function, a Schiff base, and the pyrrolyl function is bound to the metal atom. The by‐product of the reaction of the BH4− anion with the Schiff base function (a BH3 molecule) is trapped in a unique reaction mode in the coordination sphere of the metal complex. The BH3 molecule coordinates in an η2 fashion to the metal atom. The rare‐earth‐metal atoms are surrounded by the η2‐coordinated BH3 molecule, the η3‐coordinated BH4− anion, two THF molecules, and the nitrogen atoms from the Schiff base and the pyrrolyl function. All new compounds were characterized by single‐crystal X‐ray diffraction. Low‐temperature X‐ray diffraction data at 6 K were collected to locate the hydrogen atoms of [Lu(BH4){(dip)(dip‐BH3)‐pyr}(thf)2]. The (DIP2‐pyr)− borohydride and chloride complexes of neodymium, [Nd(BH4)2(dip2‐pyr)(thf)2] and [NdCl2(dip2‐pyr)(thf)]2, were also used as Ziegler–Natta catalysts for the polymerization of 1,3‐butadiene to yield poly(cis‐1,4‐butadiene). Very high activities and good cis selectivities were observed by using each of these complexes as a catalyst in the presence of various cocatalyst mixtures.
Interactions and Encapsulation of Vitamins C, B3, and B6 with Dendrimers in Water
Authors: Boisselier Elodie , Liang Liyuan , Dalko‐Csiba Maria , Ruiz Jaime , Astruc Didier
Published: April 2010

Titrations of commercial diaminobutane (DAB) and polyamidoamine (PAMAM) dendrimers by vitamins C (ascorbic acid, AA), B3 (nicotinic acid), and B6 (pyridoxine) were monitored by 1H NMR spectroscopy using the chemical shifts of both dendrimer and vitamin protons and analyzed by comparison with the titration of propylamine. Quaternarizations of the terminal primary amino groups and intradendritic tertiary amino groups, which are nearly quantitative with vitamin C, were characterized by more or less sharp variations (Δδ) of the 1H chemical shift (δ) at the equivalence points. The peripheral primary amino groups of the DAB dendrimers were quaternarized first, but not selectively, whereas a sharp chemical‐shift variation was recorded for the inner methylene protons near the tertiary amines, thereby indicating encapsulation, when all the dendritic amines were quaternarized. With DAB‐G5‐64‐NH2, some excess acid is required to protonate the inner amino groups, presumably because of basicity decrease due to excess charge repulsion. On the other hand, this selectivity was not observed with PAMAM dendrimers. The special case of the titration of the dendrimers by vitamin B6 indicates only dominant supramolecular hydrogen‐bonding interactions and no quaternarization, with core amino groups being privileged, which indicates the strong tendency to encapsulate vitamins. With vitamin B3, a carboxylic acid, titration of DAB‐G3‐16‐NH2 shows that only six peripheral amino groups are protonated on average, even with excess vitamin B3, because protonation is all the more difficult due to increased charge repulsion, as positive charges accumulate around the dendrimer. Inner amino groups interact with this vitamin, however, thus indicating encapsulation presumably with supramolecular hydrogen bonding without much charge transfer.
Controlling Stereoselectivity in the Aminocatalytic Enantioselective Mannich Reaction of Aldehydes with In Situ Generated N‐Carbamoyl Imines
Authors: Galzerano Patrizia , Agostino Dario , Bencivenni Giorgio , Sambri Letizia , Bartoli Giuseppe , Melchiorre Paolo
Published: April 2010

A simple and convenient method for the direct, aminocatalytic, and highly enantioselective Mannich reactions of aldehydes with in situ generated N‐carbamoyl imines has been developed. Both α‐imino esters and aromatic imines serve as suitable electrophilic components. Moreover, the judicious selection of commercially available secondary amine catalysts allows selective access to the desired stereoisomer of the N‐tert‐butoxycarbonyl (Boc) or N‐carbobenzyloxy (Cbz) Mannich adducts, with high control over the syn or anti relative configuration and almost perfect enantioselectivity. Besides the possibility to fully control the stereochemistry of the Mannich reaction, the main advantage of this method lies in the operational simplicity; the highly reactive N‐carbamate‐protected imines are generated in situ from stable and easily handled α‐amido sulfones.
Assembly of π‐Conjugated Phosphole Azahelicene Derivatives into Chiral Coordination Complexes: An Experimental and Theoretical Study
Authors: Graule Sebastien , Rudolph Mark , Shen Wenting , Williams J. A. Gareth , Lescop Christophe , Autschbach Jochen , Crassous Jeanne , Réau Régis
Published: April 2010

Aza[n]helicene phosphole derivatives have been prepared from aza[n]helicene diynes by the Fagan–Nugent route. Their photophysical properties (UV/Vis absorption and emission behavior) have been evaluated. Their behavior as P,N chelates towards coordination to PdII and CuI has been investigated: metal–bis(aza[n]helicene phosphole) assemblies are formed by a highly stereoselective coordination process, as demonstrated by X‐ray crystallography. An aza[6]helicene phosphole bearing an enantiopure helicene part has been obtained, which allows the preparation of enantiopure PdII and CuI complexes with original topologies and high molar rotation (MR) and circular dichroism (CD). The structure–property relationship established from the experimental data has been studied in detail by theoretical studies (TDDFT calculations of UV/Vis, CD, and MR). Aza[n]helicene phosphole derivatives show π conjugation extended over the entire molecule, and its influence on the MR of aza[6]helicene phosphole 5 c has been demonstrated. Finally, it has been shown that the nature of the metal (coordination geometry and electronic interaction) can have a great impact on the amplitude of the chiroptical properties in metal–bis(aza[n]helicene phosphole) assemblies.
Hierarchical ZSM‐5 Zeolites in Shape‐Selective Xylene Isomerization: Role of Mesoporosity and Acid Site Speciation
Authors: Fernandez Christian , Stan Irina , Gilson Jean‐Pierre , Thomas Karine , Vicente Aurélie , Bonilla Adriana , Pérez‐Ramírez Javier
Published: April 2010

The isomerization of o‐xylene, a prototypical example of shape‐selective catalysis by zeolites, was investigated on hierarchical porous ZSM‐5. Extensive intracrystalline mesoporosity in ZSM‐5 was introduced by controlled silicon leaching with NaOH. In addition to the development of secondary porosity, the treatment also induced substantial aluminum redistribution, increasing the density of Lewis acid sites located at the external surface of the crystals. However, the strength of the remaining Brønsted sites was not changed. The mesoporous zeolite displayed a higher o‐xylene conversion than its parent, owing to the reduced diffusion limitations. However, the selectivity to p‐xylene decreased, and fast deactivation due to coking occurred. This is mainly due to the deleterious effect of acidity at the substantially increased external surface and near the pore mouths. A consecutive mild HCl washing of the hierarchical zeolite proved effective to increase the p‐xylene selectivity and reduce the deactivation rate. The HCl‐washed hierarchical ZSM‐5 displayed an approximately twofold increase in p‐xylene yield compared to the purely microporous zeolite. The reaction was followed by operando infrared spectroscopy to simultaneously monitor the catalytic performance and the buildup of carbonaceous deposits on the surface. Our results show that the interplay between activity, selectivity, and stability in modified zeolites can be optimized by relatively simple post‐synthesis treatments, such as base leaching (introduction of mesoporosity) and acid washing (surface acidity modification).
Template‐Assembled Synthetic G‐Quadruplex (TASQ): A Useful System for Investigating the Interactions of Ligands with Constrained Quadruplex Topologies
Authors: Murat Pierre , Bonnet Romaric , Van der Heyden Angéline , Spinelli Nicolas , Labbé Pierre , Monchaud David , Teulade‐Fichou Marie‐Paule , Dumy Pascal , Defrancq Eric
Published: April 2010

A new biomolecular device for investigating the interactions of ligands with constrained DNA quadruplex topologies, using surface plasmon resonance (SPR), is reported. Biomolecular systems containing an intermolecular‐like G‐quadruplex motif 1 (parallel G‐quadruplex conformation), an intramolecular G‐quadruplex 2, and a duplex DNA 3 have been designed and developed. The method is based on the concept of template‐assembled synthetic G‐quadruplex (TASQ), whereby quadruplex DNA structures are assembled on a template that allows precise control of the parallel G‐quadruplex conformation. Various known G‐quadruplex ligands have been used to investigate the affinities of ligands for intermolecular 1 and intramolecular 2 DNA quadruplexes. As anticipated, ligands displaying a π‐stacking binding mode showed a higher binding affinity for intermolecular‐like G‐quadruplexes 1, whereas ligands with other binding modes (groove and/or loop binding) showed no significant difference in their binding affinities for the two quadruplexes 1 or 2. In addition, the present method has also provided information about the selectivity of ligands for G‐quadruplex DNA over the duplex DNA. A numerical parameter, termed the G‐quadruplex binding mode index (G4‐BMI), has been introduced to express the difference in the affinities of ligands for intermolecular G‐quadruplex 1 against intramolecular G‐quadruplex 2. The G‐quadruplex binding mode index (G4‐BMI) of a ligand is defined as follows: G4‐BMI=KDintra/KDinter, where KDintra is the dissociation constant for intramolecular G‐quadruplex 2 and KDinter is the dissociation constant for intermolecular G‐quadruplex 1. In summary, the present work has demonstrated that the use of parallel‐constrained quadruplex topology provides more precise information about the binding modes of ligands.
Asymmetric Catalytic Hydrogenolysis of ArylHalide Bonds in Fused Arene Chromium and Ruthenium Complexes
Authors: Mercier Audrey , Urbaneja Xavier , Yeo Wee Chuan , Chaudhuri Piyali Datta , Cumming Graham R. , House David , Bernardinelli Gérald , Kündig E. Peter
Published: April 2010

Access to highly enantioenriched planar chiral [Cr(5‐bromonaphthalene)(CO)3] (6), [Ru(η5‐C5R5)(5‐bromonaphthalene)][PF6] (42) and [Ru(η5‐C5R5)(4‐bromoindene)] (44) was sought using asymmetric hydrogenolysis of [Cr(5,8‐dibromonaphthalene)(CO)3] (5), [Ru(η5‐C5R5)(5,8‐dibromonaphthalene)] (39) and [Ru(η5‐C5R5)(4,7‐dibromoindene)] (40), respectively. Initial efforts focused on the chromium complex 5. Pd0 catalysts with dimethoxyethane as the solvent and LiBH4 or NaBH3CN as a hydride source worked best. Nineteen chiral bidentate phosphorus ligands were screened in this reaction. Asymmetric induction was low to modest with product ee’s in the range of 4 to 52 % and yields of 6 of up to 70 %. Chiral phosphoramidite ligands proved superior and a bulky ligand derived from a Whitesell amine and 3,3′‐diphenyl‐binaphtol afforded 6 with an ee of 97 %. The high enantioselectivity is largely due to the initial desymmetrization reaction though kinetic resolution also plays an important role as shown by the determination of a selectivity factor s=8.5 at −10 °C. Initially high ligand loadings (4 equiv/Pd) were necessary to achieve good asymmetric induction. This could be traced to the trapping of the chiral ligand by borane formed in the reaction. Addition of 1,4‐diazabicyclo[2.2.2]octane (DABCO) suppressed this, and its addition led to the use of Pd and chiral ligand in a 1:1.2 ratio. Asymmetric hydrogenolysis of cationic dibromonaphthalene and neutral dibromoindenyl complexes of Ru cyclopentadienyl complexes was investigated and afforded the following results: [RuCp(5‐bromonaphthalene)][PF6] (39 a; 75 %, 90 % ee), [RuCp*(5‐bromonaphthalene)] [PF6] (39 b; 88 %, 99 % ee), [RuCp(4‐bromoindenyl)] (44 a; 72 %, 96 % ee), and [RuCp*(4‐bromoindenyl)] (44 b; 62 %, 68 % ee).
Selective Gas Adsorption in the Flexible Metal–Organic Frameworks Cu(BDTri)L (L=DMF, DEF)
Authors: Demessence Aude , Long Jeffrey R.
Published: April 2010

Use of the ditopic ligand 1,4‐benzenedi(1H‐1,2,3‐triazole) (H2BDTri) enabled isolation of two new three‐dimensional metal–organic frameworks of formulae Cu(BDTri)L in which L=DMF (1) and diethylformamide (DEF; 2). These compounds have the same primary structure, featuring one‐dimensional channels with the bridging DMF or DEF molecules pointing into the cavity. Upon exposure to solvent vapors, both display a reversible flexibility, as characterized by single‐crystal to single‐crystal phase transitions in 1. The O2 adsorption isotherms for the compounds show a two‐step adsorption behavior associated with a permanent microporosity and a pore‐opening process. In the case of N2 adsorption, only 1 exhibits a two‐step adsorption isotherm, whereas 2 does not present any pore opening, demonstrating that design of a flexible framework cavity can control the pore opening and thereby possibly enhance O2/N2 separation.
Transition‐Metal‐Catalyzed Synthesis of Hydroxylated Arenes
Authors: Alonso Diego A. , Nájera Carmen , Pastor Isidro M. , Yus Miguel
Published: April 2010

An overview of the recent bibliography in the transition‐metal‐catalyzed hydroxylation of aryl derivatives is presented. Two reaction protocols are considered: 1) CH activation/hydroxylation and, 2) cross‐coupling hydroxylation of aryl halides. The achievements and limitations for both procedures are described taking into consideration different metal catalyst/oxidant combinations.
ChemInform Abstract: Synthesis, Structure, and Bonding in K12Au21Sn4. A Polar Intermetallic Compound with Dense Au20 and Open AuSn4 Layers.
Authors: Li Bin , Kim Sung‐Jin , Miller Gordon J. , Corbett John D.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Combustion Synthesis and Luminescence Investigation of Na3Al2(PO4)3:RE (RE: Ce3+, Eu3+ and Mn2+) Phosphor.
Authors: Nagpure I. M. , Shinde K. N. , Kumar Vinay , Ntwaeaborwa O. M. , Dhoble S. J. , Swart H. C.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Multiband Orange—Red Photoluminescence of Eu3+ Ions in New “114” LnBaZn3GaO7 and LnBaZn3AlO7 Oxides.
Authors: Saradhi M. P. , Raveau B. , Caignaert V. , Varadaraju U. V.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Highly Uniform YBO3 Hierarchical Architectures: Facile Synthesis and Tunable Luminescence Properties.
Authors: Jia Guang , You Hongpeng , Liu Kai , Zheng Yuhua , Guo Ning , Jia Junjiao , Zhang Hongjie
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Luminescence Properties of Lanthanide and Transition Metal Ion‐Doped Ba2LaNbO6: Detection of MnO8‐6 and CrO9‐6 Clusters.
Authors: Tanner Peter A. , Pan Zaifa
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Isothermal Section of the Cu—Mn—Si Ternary System at 700 °C.
Authors: Liu Shuhong , Du Yong , Zhang Chao , Xu Honghui , Huang Baiyun , Liang Jianlie , Zhou Yichun , Zheng Feng , Li Yiwei
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Photolysis of Aqueous [(NH3)5Os(μ‐N2)Os (NH3)5]5+: Cleavage of Dinitrogen by an Intramolecular Photoredox Reaction.
Authors: Kunkely Horst , Vogler Arnd
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Direct Solid‐State Synthesis at High Pressure of New Mixed‐Metal Oxynitrides: LnZrO2N (Ln: Pr, Nd, and Sm).
Authors: Yang Minghui , Rodgers Jennifer A. , Middler Lawrence C. , Oro‐Sole Judith , Jorge A. Belen , Fuertes Amparo , Attfield J. Paul
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Studies on the New UFe2B6 Phase.
Authors: Dias M. , Carvalho P. A. , Sologub O. , Pereira L. C. J. , Santos I. C. , Goncalves A. P.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Nitrate and Perchlorate Complexes of Uranium(IV).
Authors: Crawford Margaret‐Jane , Ellern Arkady , Karaghiosoff Konstantin , Mayer Peter
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A New Ni12 Cluster Based on Polyoxometalate Ligands.
Authors: Zhang Hong‐Mei , Li Yang‐Guang , Lu Ying , Clerac Rodolphe , Zhang Zhi‐Ming , Wu Qiong , Feng Xiao‐Jia , Wang En‐Bo
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: AgIISO4: A Genuine Sulfate of Divalent Silver with Anomalously Strong One‐Dimensional Antiferromagnetic Interactions.
Authors: Malinowski Przemyslaw J. , Derzsi Mariana , Mazej Zoran , Jaglicic Zvonko , Gawel Bartlomiej , Lasocha Wieslaw , Grochala Wojciech
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Palladium‐Catalyzed [3C + 2C + 2C] Cycloaddition of Enynylidenecyclopropanes: Efficient Construction of Fused 5‐7‐5 Tricyclic Systems.
Authors: Bhargava Gaurav , Trillo Beatriz , Araya Marisel , Lopez Fernando , Castedo Luis , Mascarenas Jose L.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Sigma‐1 Ligands: Tic‐Hydantoin as a Key Pharmacophore.
Authors: Toussaint Marion , Mousset Deborah , Foulon Catherine , Jacquemard Ulrich , Vaccher Claude , Melnyk Patricia
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Highly Active and Selective Semihydrogenation of Alkynes with the Palladium Nanoparticles‐Tetrabutylammonium Borohydride Catalyst System.
Authors: Hori Junichi , Murata Kunihiko , Sugai Toshiki , Shinohara Hisanori , Noyori Ryoji , Arai Noriyoshi , Kurono Nobuhito , Ohkuma Takeshi
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Expanded Scope for the Iridium‐Catalyzed Asymmetric Isomerization of Primary Allylic Alcohols Using Readily Accessible Second‐Generation Catalysts.
Authors: Mantilli Luca , Mazet Clement
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: N‐Arylation of Azaheterocycles with Aryl and Heteroaryl Halides Catalyzed by Iminodiacetic Acid Resin‐Chelated Copper Complex.
Authors: Wu Xiang Mei , Wang Yan
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The First DMAP‐Mediated Palladium‐Free Tsuji—Trost‐Type Reaction of Cyclic and Acyclic Baylis—Hillman Alcohols with Active Methylene Compounds.
Authors: Mhasni Olfa , Rezgui Farhat
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Acid‐Mediated Activation of Modified Ring‐Closing Metathesis Catalysts.
Authors: Kim Seyoung , Hwang Wonmi , Lim In Seon , Kim Sung Hye , Lee Sang‐gi , Kim B. Moon
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Scandium‐Catalyzed Regio‐ and Stereospecific Methylalumination of Silyloxy/Alkoxy‐Substituted Alkynes and Alkenes.
Authors: Takimoto Masanori , Usami Saori , Hou Zhaomin
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Unexpected Products from the Attempted Organolithium‐Mediated Conversion of β‐Methoxy Aziridines into Allylic Amines.
Authors: Coote Susannah C. , O'Brien Peter
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Cooperativity of Regiochemistry Control Strategies in Reductive Couplings of Propargyl Alcohols and Aldehydes.
Authors: Malik Hasnain A. , Chaulagain Mani Raj , Montgomery John
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Catalytic Asymmetric Alkylation of α‐Cyanocarboxylates and Acetoacetates Using a Phase‐Transfer Catalyst.
Authors: Nagata Kazuhiro , Sano Daisuke , Shimizu Yu , Miyazaki Michiko , Kanemitsu Takuya , Itoh Takashi
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Hydrodeoxygenation of Bio‐Derived Phenols to Hydrocarbons Using RANEY® Ni and Nafion/SiO2 Catalysts.
Authors: Zhao Chen , Kou Yuan , Lemonidou Angeliki A. , Li Xuebing , Lercher Johannes A.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.