bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogenisation of Acylperrhenate on Mesoporous Materials and its Application in Catalysis
Authors: Veljanovski Draganco , Sakthivel Ayyamperumal , Herrmann Wolfgang A. , Kühn Fritz E. 
Published: August 2006

AbstractAcylperrhenate is grafted on the surface of mesoporous silicates and aluminiosilicate molecular sieves through available surface silanol and acidic hydroxy groups. The intactness of the mesoporous supports and the nature of the catalytic species is demonstrated by XRD, TEM, FT‐IR, N2 adsorption‐desorption and elemental analysis. The grafted materials are applied for alkene epoxidation. The catalysts are found to be stable against decomposition on the surfaces and to exhibit good catalytic activity. However, during the course of repeated catalytic runs, some leaching associated with subsequent decomposition of the catalyst is observed, reducing the activity of the materials.
Polyglycerol‐Supported Chromium‐Salen as a High‐Loading Dendritic Catalyst for Stereoselective Diels–Alder Reactions
Authors: Hajji Chakib , Roller Sebastian , Beigi Maryam , Liese Andreas , Haag Rainer 
Published: August 2006

AbstractIn this paper we demonstrate the application of hyperbranched polyglycerol (PG) 3 as a polymeric support for asymmetric catalysis. A new polyglycerol‐supported unsymmetrical salen ligand 4 is described, which was successfully purified by gel permeation chromatography (GPC) or by ultrafiltration. After the insertion of the metal, e.g., chromium, the corresponding polymeric chromium complex was used as catalyst for asymmetric Diels–Alder reactions between Danishefsky’s diene and benzaldehyde. The catalytic activities (up to 98 % conversion) and enantioselectivities (up to 78 % ee) were comparable to the original catalyst reported by Jacobsen. The soluble polyglycerol‐supported catalysts were recovered by dialysis after the catalytic reactions and were recycled two times to afford identical reactivities as in the first run, with slightly reduced enantioselectivities. Moreover, this polymeric support catalyst showed a high retention (99.02 %) in a continuously operated membrane reactor.
Immobilization of Osmium Catalysts for Asymmetric Dihydroxylation of Olefins
Authors: Kobayashi Shū , Sugiura Masaharu 
Published: August 2006

AbstractOsmium‐catalyzed asymmetric dihydroxylation provides powerful synthetic routes to optically active vicinal diols from olefins with high enantioselectivity. High catalytic efficiency using only 0.2–1.0 mol % of the osmium catalyst has been attained, and the chiral ligand may be recoverable in large‐scale synthesis by extraction with dilute sulfuric acid. However, in spite of the significant advances in this transformation, high toxicity and volatility of the osmium components as well as possible contamination of toxic osmium species in the products have been obstacles for industrial applications. To address this issue, considerable efforts have been devoted to immobilization of the osmium catalyst. This review summarizes several promising methods for immobilization of the osmium components, especially focusing on solid phase‐supported osmium catalysts for asymmetric dihydroxylation.
Linking Antley–Bixler syndrome and congenital adrenal hyperplasia: A novel case of P450 oxidoreductase deficiency
Authors: Williamson L. , Arlt W. , Shackleton C. , Kelley R.I. , Braddock S.R. 
Published: August 2006

AbstractThe Antley–Bixler syndrome (ABS) is a multiple congenital malformation syndrome with craniosynostosis, radiohumeral synostosis, femoral bowing, choanal atresia or stenosis, joint contractures, urogenital abnormalities and, often, early death. Autosomal recessive and dominant inheritance have been postulated, as has fluconazole teratogenesis. Mutations in POR (P450 (cytochrome) oxidoreductase, an essential electron donor to enzymes participating in cholesterol biosynthesis), have been identified in some patients with the ABS phenotype. Recent evidence suggests that these mutations cause attenuated steroid hydroxylation, which in turn, causes congenital adrenal hyperplasia (CAH) with ambiguous genitalia in both sexes and glucocorticoid deficiency. Here, we report on a new patient with findings of both ABS and CAH that further illustrates how low maternal estriol at prenatal screening can serve as a marker steroid facilitating early diagnosis. © 2006 Wiley‐Liss, Inc.
Risk of limb deficiency defects associated with NAT1, NAT2, GSTT1, GSTM1, and NOS3 genetic variants, maternal smoking, and vitamin supplement intake
Authors: Carmichael Suzan L. , Shaw Gary M. , Yang Wei , Iovannisci David M. , Lammer Edward 
Published: August 2006

AbstractIncreasing epidemiologic evidence suggests that genetic susceptibilities contribute to birth defects risks, especially in combination with other environmental exposures. This analysis examines the association of risk of limb deficiency defects with infant genotypes for N‐acetyltranferases (NAT1, NAT2), glutathione‐S‐tranferases (GSTT1, GSTM1), and endothelial nitric oxide synthase (NOS3). The combined effects of infant genotype with maternal smoking and supplement intake were also examined. The authors genotyped 92 cases and 201 non‐malformed controls from a California population‐based case‐control study (1987–1988 birth cohort). Several of the infant genotypes were associated with an at least 1.5‐fold increased risk for limb deficiency defects: homozygosity for the NAT1 1088 and 1095 polymorphisms, heterozygosity and homozygosity for the NOS3 A(−922)G polymorphism, and heterozygosity (but not homozygosity) for the NOS3 G894T polymorphism. The authors hypothesized that the effects of selected variant genotypes in the presence of maternal smoking, or in the absence of supplement intake, may exceed effects of any of these factors alone. A few observations suggested that risks were greatest among infants with variant genotypes, whose mothers also smoked or did not take supplements, but most did not, and risk estimates were imprecise. Further studies exploring genetic susceptibility and combined gene‐environment effects with respect to limb development will be important to continued improvement of our understanding of the etiology of limb anomalies. © 2006 Wiley‐Liss, Inc.
High cognitive functioning and behavioral phenotype in Pallister‐Killian syndrome
Authors: Stalker Heather J. , Gray B.A. , Bent‐Williams A. , Zori R.T. 
Published: August 2006

AbstractPallister‐Killian syndrome (PKS) is a rare syndrome of multiple congenital anomalies attributable to the presence of a mosaic supernumerary isochromosome 12p. The syndrome presents with a recognizable pattern of findings including: pigmentary skin changes, characteristic facial features (sparse anterior scalp hair, flattened midface, macrostomia, and coarsening of the facial features), and developmental delay. The developmental phenotype of PKS is quite variable, but most are considered to fall into the profound range of developmental retardation. We report on an individual with classical features of PKS with development significantly better than that reported in the literature. Developmental and behavioral testing in this individual alters the range of developmental expectation in PKS, and highlights the need for consideration of chromosomal analysis in individuals with normal or near‐normal intelligence if other physical phenotypic features of PKS are present. © 2006 Wiley‐Liss, Inc.
Prenatal diagnosis of episodic tachypnea in an infant with OFD VI
Authors: McPherson Elizabeth , Zaleski Christina , Mascola Maria 
Published: August 2006

AbstractEpisodic tachypnea is a typical neonatal presentation of Joubert syndrome, but may also occur in infants with other anomalies of the cerebellar vermis. Even though fetuses at risk for Joubert syndrome are usually closely followed by ultrasound, this respiratory pattern has only once been described prenatally. We describe a patient who presented prenatally with posterior meningocele, Dandy‐Walker cyst, and four limb polydactyly on ultrasound. Amniocentesis showed a normal male karyotype and normal 7DHC. At 31 weeks, episodic fetal tachypnea was noted on ultrasound. The working diagnosis was Joubert syndrome or oro‐facio‐digital syndrome type VI (OFD VI). At birth, in addition to the findings noted prenatally, he had multiple nodules of his tongue, a Y‐shaped metacarpal and micropenis. His respiratory pattern was notable for alternating tachypnea and apnea with respiratory rates up to 200 followed by apnea and bradycardia. Magnetic resonance image showed Dandy‐Walker with massive 4th ventricle, complete absence of the cerebellar vermis, hypoplastic brainstem, and small meningocele. Development is profoundly delayed and he remains ventilator dependent. Both the previously described Joubert patient with prenatally recognized tachypnea, and our patient are atypical for Joubert syndrome since they have polydactyly (which occurs in only 8% of Joubert patients) and hamartomas of the tongue (which occur in 2%). Despite the tongue hamartomas, these patients are not entirely typical for OFD VI, since their polydactyly is postaxial. The observation of prenatal tachypnea in these two patients, but not in typical Joubert patients, suggests they have either a variant of OFD VI or a new Joubert or OFD‐like syndrome. © 2006 Wiley‐Liss, Inc.
DHCR7 mutation carrier rates and prevalence of the RSH/Smith‐Lemli‐Opitz syndrome: Where are the patients?
Authors: Nowaczyk Małgorzata J.M. , Waye John S. , Douketis James D. 
Published: August 2006

AbstractRSH/Smith‐Lemli‐Opitz (SLOS) is an inborn error of metabolism with protean manifestations. Its exact incidence and prevalence are not known; however, the carrier rate for the most frequently occurring mutation, the null mutation IVS8‐1G > C, is approximately 1 in 100 for the Caucasian population in North America (1%) and possibly as high as 1 in 50 to 1 in 30 in Central European populations (2–3.3%). Based on the allele frequencies and the proportion of this mutation observed in various patient populations, the expected incidence of RSH/SLOS in those populations was calculated and reported to be between 1 in 1,590 and 1 in 17,000. However, around the world the observed prevalence and incidence are much lower than those calculated from the individual mutation carrier rates observed in any given population. The discrepancy between the expected incidence and prevalence can be explained only in part by the neonatal and infancy deaths of the most severely affected children with RSH/SLOS and the under ascertainment of mild and atypical cases at the mild end of the spectrum. RSH/SLOS may be responsible for a high number of miscarriages. Recent observations estimate the prevalence of SLOS at 16 weeks of gestation as similar to that observed at birth (approximately 1 in 60,000) suggesting that either reduced fertility of carrier couples or losses of affected embryos or fetuses in the first trimester play a significant role in reducing the second trimester prevalence of RSH/SLOS. It is possible that the estimates of carrier rates based on population screening for the most commonly occurring mutations may not reflect the true carrier rates in the population. In order to reconcile the above‐mentioned paradoxes, we propose a model based on a higher than observed carrier frequency of the most common mutation and on very high fetal loss of homozygotes for that mutation. © 2006 Wiley‐Liss, Inc.
Clinical experience with array CGH: Case presentations from nine months of practice
Authors: Poss Alexis F. , Goldenberg Paula C. , Rehder Catherine W. , Kearney Hutton M. , Melvin Elizabeth C. , Koeberl Dwight D. , McDonald Marie T. 
Published: August 2006

AbstractA total of 124 individuals were tested in the initial 9 months that array CGH technology was offered to clinical genetics patients. In 11 of these patients array CGH identified a previously unsuspected diagnosis. A suspected diagnosis was confirmed in three patients. A single case in this series proved to be a polymorphic copy number variant. This paper describes five of the patients with previously unsuspected diagnoses in detail. We suggest that array CGH is an improved tool ready for routine use in clinical genetics. © 2006 Wiley‐Liss, Inc.
Prevalence of Angelman syndrome and Prader–Willi syndrome in Estonian children: Sister syndromes not equally represented
Authors: Õiglane‐Shlik Eve , Talvik Tiina , Žordania Riina , Põder Haide , Kahre Tiina , Raukas Elve , Ilus Tiiu , Tasa Gunnar , Bartsch Oliver , Väisänen Marja‐Leena , Õunap Katrin 
Published: August 2006

AbstractIn 2000–2004, we performed a focused search for individuals with Angelman syndrome (AS) and Prader–Willi syndrome (PWS) aiming to establish the prevalence data for the individuals born between 1984 and 2004 in Estonia. All persons with probable AS or PWS (n = 184) were studied using the DNA methylation test. Individuals with abnormal methylation were all further tested by chromosomal and FISH analysis, and if necessary for uniparental disomy and UBE3A gene mutation. Nineteen cases with abnormal methylation test result were identified. Seven of them had AS, including six (85.7%) due to 15q11‐13 deletion and one paternal UPD15. Twelve subjects had PWS: 4 (33%) 15q11‐13 deletions, 6 (50%) maternal UPD15, 1 unbalanced chromosome 14;15 translocation resulting in a chromosome 15pter‐q13 deletion, and 1 Robertsonian 15q;15q translocation. The minimum livebirth prevalence in 1984–2004 for AS was 1:52,181 (95% CI 1:25,326–1:1,29,785) and for PWS 1:30,439 (95% CI 1:17,425–1:58,908). The livebirth prevalence of AS and PWS increased within this period, but the change was statistically significant only for PWS (P = 0.032), from expected 1:88,495 (95% CI 1:24,390–1:3,22,580) to expected 1:12,547 (95% CI 1:540–1:29,154). Six individuals with AS and 11 with PWS were alive on the prevalence day (January 1, 2005), indicating the point prevalence proportion of 1:56,112 (95% CI 1:25,780–1:1,52,899) and 1:30,606 (95% CI 1:17,105–1:61,311), respectively. Our results showing the birth prevalence of AS 1.7 times less than PWS challenge the opinion that both syndromes are equally represented, and are in line with the view that mutations in sperm and oocytes occur at different frequencies. © 2006 Wiley‐Liss, Inc.
Atrioventricular block and wiry hair in Teebi hypertelorism syndrome
Authors: Han Xiao‐Dong , Cox Vicki , Slavotinek Anne 
Published: August 2006

AbstractWe report on a 4½‐year‐old girl with clinical features of Teebi hypertelorism syndrome (THS), including a prominent forehead with a widow's peak, heavy and broad eyebrows, hypertelorism, long palpebral fissures, ptosis, a thin upper lip, a grooved chin, and a left preauricular cyst. She required a pacemaker for third degree atrioventricular (AV) block, a finding that has not been previously reported in 36 other patients with THS and for which we were unable to identify other causes. We have reviewed the previous reports of THS and note a characteristic facial appearance with hypertelorism, heavy, broad, and arched eyebrows, a thin upper lip with a long and deep philtrum, and a prominent forehead. Structural cardiac defects were present in five patients, implying that cardiac investigations are warranted in patients with a cardiac murmur and a clinical diagnosis of THS. © 2006 Wiley‐Liss, Inc.
Catalytic polymerization of phenylacetylene with dimeric [Rh(OMe)(cod)]2 complex in ionic liquids
Authors: Gil Wojciech , Trzeciak Anna M. , Ziółkowski Józef J. 
Published: August 2006

AbstractDimeric rhodium(I) complex [Rh(OMe)(cod)]2 was found to be an active catalyst of phenylacetylene polymerization to poly(phenylacetylene) (PPA) in ionic liquids containing imidazolium or pyridinium cations. The highest yield of PPA (92%) was obtained in 1‐butyl‐4‐methylpyridinium tetrafluoroborate as reaction medium. The yield of PPA in imidazolium ionic liquids containing BF4− or PF6− anions increased to 83–99% when Et3N or cycloocta‐1,5‐diene were added as co‐catalysts. In 1‐methyl‐3‐octylimidazolium chloride (MOI · Cl) polymerization rate was much lower than in other ionic liquids, although the highest Mw (72 400) was obtained. Spectroscopic studies confirmed that [Rh(OMe)(cod)]2 reacted with MOI · Cl forming new carbene Rh(I) complex, which can participate in the polymerization process. Copyright © 2006 John Wiley & Sons, Ltd.
Antibiotic Resistance: Mono‐ and Dinuclear Zinc Complexes as Metallo‐β‐Lactamase Mimics
Authors: Tamilselvi A. , Nethaji Munirathinam , Mugesh G. 
Published: August 2006

AbstractBiomimetic systems containing one or two zinc(II) ions supported by phenolate ligands were developed as functional mimics of metallo‐β‐lactamase. These complexes were shown to catalytically hydrolyze β‐lactam substrates, such as oxacillin and penicillin G. The dinuclear zinc complex 1, which has a coordinated water molecule, exhibits high β‐lactamase activity, whereas the dinuclear zinc complex 2, which has no water molecules, but labile chloride ligands, shows a much lower activity. The high β‐lactamase activity of complex 1 can be ascribed to the presence of a zinc‐bound water molecule that is activated by being hydrogen bonded to acetate substituents. The kinetics of the hydrolysis of oxacillin by complex 1 and the effect of pH on the reaction rates are reported in detail. In addition, the kinetic parameters obtained for the synthetic analogues are compared with those of the natural metallo‐β‐lactamase from Bacillus cereus (BcII). To understand the role of the second metal ion in hydrolysis, the syntheses and catalytic activities of two mononuclear complexes (3 and 4) that include coordinated water molecules are described. Interestingly, the mononuclear zinc complexes 3 and 4 also exhibit high activity, supporting the assumption that the second zinc ion is not crucial for the β‐lactamase activity.
Dirubidium Fluorotrioxophosphate, Rb2PO3F, at 290 and 130 K, and Dicaesium Fluorotrioxophosphate, Cs2PO3F, at 240 and 100 K.
Authors: Fabry Jan , Dusek Michal , Fejfarova Karla , Krupkova Radmila , Vanek Premysl , Cisarova Ivana 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Microalga Chlorella sorokiniana: A New Sulfoxidation Biocatalyst.
Authors: Daligault Franck , Nugier‐Chauvin Caroline , Patin Henri 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Diols Using the Hypervalent Iodine(III) Reagent, Phenyliodine(III) Bis(trifluoroacetate).
Authors: Celik Murat , Alp Cemalettin , Coskun Betuel , Gueltekin M Serdar , Balci Metin 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Facile and Chemoselective Conjugate Reduction Using Polymethylhydrosiloxane (PMHS) and Catalytic B(C6F5)3.
Authors: Chandrasekhar Srivari , Chandrashekar Gudise , Reddy Marepally Srinivasa , Srihari Pabbaraja 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A New Class of Versatile Chiral‐Bridged Atropisomeric Diphosphine Ligands: Remarkably Efficient Ligand Syntheses and Their Applications in Highly Enantioselective Hydrogenation Reactions.
Authors: Qiu Liqin , Kwong Fuk Yee , Wu Jing , Lam Wai Har , Chan Shusun , Yu Wing‐Yiu , Li Yue‐Ming , Guo Rongwei , Zhou Zhongyuan , Chan Albert S. C. 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Facile N‐Arylation of Amines and Sulfonamides and O‐Arylation of Phenols and Arenecarboxylic Acids
Authors: Liu Zhijian , Larock Richard C. 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Facile N‐Arylation of Amines and Sulfonamides and O‐Arylation of Phenols and Arenecarboxylic Acids.
Authors: Liu Zhijian , Larock Richard C. 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Stereoselective Functionalization of β‐Iodo‐α,β‐Unsaturated Ketones via an Iodine—Copper Exchange Reaction.
Authors: Yang Xiaoyin , Knochel Paul 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Rapid and Efficient Method for Acetylation of Alcohols and Phenols with Acetic Anhydride Catalyzed by Silica Sulfate.
Authors: Jin Tong‐Shou , Zhao Ying , Liu Li‐Bin , Chen Zhuo , Li Tong‐Shuang 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Dimroth Rearrangement in Synthesis of a Heteroditopic Receptor.
Authors: Geide I. V. , Glukhareva T. V. , Matern A. I. , Morzherin Yu. Yu. 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Preparation of Cyclic N‐tert‐Butylsulfonyl Enamines by Rh(II)‐Mediated Ring Expansion of α‐Diazoesters.
Authors: Chen Shufeng , Zhao Yonghua , Wang Jianbo 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Enantioselective Aldol Reactions of Trichlorosilyl Enol Ethers Catalyzed by the Chiral Phosphine Oxide BINAPO.
Authors: Kotani Shunsuke , Hashimoto Shunichi , Nakajima Makoto 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Studies on Novel Synthetic Methodologies. Part 67. (Bromodimethyl)sulfonium Bromide Catalyzed One‐Pot Synthesis of α‐Aminonitriles.
Authors: Das Biswanath , Ramu R. , Ravikanth B. , Reddy K. Ravinder 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Expedient Synthesis of 1‐Vinylpyrrole‐2‐carbaldehydes.
Authors: Mikhaleva Al'bina I. , Zaitsev Alexey B. , Ivanov Andrey V. , Schmidt Elena Yu. , Vasil'tsov Alexander M. , Trofimov Boris A. 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
One‐Pot Synthesis of 1,2,4‐Oxadiazoles from Carboxylic Acid Esters and Amidoximes Using Potassium Carbonate.
Authors: Amarasinghe Kande K. D. , Maier Matthew B. , Srivastava Anil , Gray Jeffrey L. 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.