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The room-temperature photochemical reaction of the tricarbollide anion [nido-7,8,9-C3B8H11]^- (1a) with [CpFe(C6H6)]⁺ proceeds without cluster rearrangement to form the 12-vertex closo-ferratricarbollide 1-Cp-1,2,3,4-FeC3B8H11 (2a, the metal atom is assigned number 1). 2a rearranges to the isomeric complex 1-Cp-1,2,3,5-FeC3B8H11 (2b) at 110 °C and further to 1-Cp-1,2,4,10-FeC3B8H11 (2c) at 165 °C. The reaction of 1a with [Cp*RuCl]4 is accompanied by polyhedral rearrangement giving 1-Cp*-1,2,3,5-RuC3B8H11 (3b). Its further isomerization occurs slowly at room temperature and rapidly at 65 °C to give complex 1-Cp*-1,2,4,10-RuC3B8H11 (3c). Similar reactions of [nido-7,8,10-C3B8H11]^- (1b) with [CpFe(C6H6)]⁺ and [Cp*RuCl]4 afford 2b and 3b, respectively. A diamond-square-diamond mechanism for the 2a → 2b → 2c rearrangement sequence is proposed. The relative stability of isomers 2a−c was estimated by DFT calculations. The constitution of the compounds prepared was determined by multinuclear NMR spectroscopy and mass spectrometry. The structures of 2a, 2b, and 3c were established by X-ray diffraction.

We describe an efficient protocol to effect multisite conjugation reactions to oligomers on solid-phase support. Sequence-specific N-substituted glycine “oligopeptoids” were utilized as substrates for azide−alkyne cycloaddition reactions. Diverse groups, including nucleobases and fluorophores, were conjugated at up to six positions on peptoid side chains with yields ranging from 88 to 96%. This strategy will be broadly applicable for generating polyvalent displays on peptides and other scaffolds, allowing precise control of spacing between the displayed groups.

Background & Aims: Endoscopy is commonly performed to evaluate symptoms of dyspepsia. The aim of this study was to characterize patients who receive endoscopy for dyspepsia and measure predictors of primary endoscopic outcomes, utilizing a large national endoscopic database. Methods: The Clinical Outcomes Research Initiative (CORI) receives endoscopy reports from a network of 74 sites in the United States. Sixty-one percent of reports come from private practice settings. Patients with reflux dyspepsia and nonreflux dyspepsia were identified from January 2000 to June 2002. Patients with dysphagia and known Barrett's esophagus were excluded. Primary endoscopic outcomes included esophageal inflammation and stricture, gastric ulcer, duodenal ulcer, suspected Barrett's esophagus (>=2cm), and suspected esophageal and gastric malignancy. The presence or absence of alarm symptoms (vomiting, weight loss, and evidence of GI blood loss) was determined. Adjusted relative risk (RR) for predicting serious outcomes was calculated in a multivariate model. Results: We received 117,497 endoscopic reports, representing 99,558 unique patients. Dyspepsia, with and without reflux symptoms, accounted for 43% of upper endoscopies. Among dyspeptic patients, 36.5% were younger than 50 years of age without alarm symptoms. Esophageal or gastric malignancy in patients with dyspepsia was associated with increasing age, male sex, Asian race, Native American race, and symptoms of weight loss and vomiting. Suspected Barrett's esophagus (>=2cm) was associated with reflux symptoms, male sex, age, and white race. Ulcers were associated with evidence of bleeding, vomiting, male sex, black race, and Hispanic ethnicity. Conclusions These practice-based data reveal important practice behaviors and outcomes.

The purpose of this paper is to give a number of characterizations of reflexive Banach spaces having Schauder bases. We show that a Banach space $ X$ is contained in either $ X$ $ {X^{\ast}}$. It follows that a Banach space with an unconditional basis is reflexive if and only if no basis is of type . It is also shown that a Banach space with a basis is reflexive if and only if every basis converges weakly to zero.

Let X and Y denote Banach spaces with bases $ ({x_i})$, respectively, and let $ X{ \otimes _\varepsilon }Y$ $ X{ \otimes _\pi }Y$ $ \varepsilon $ crossnorms of the algebraic tensor product $ X \otimes Y$ The purpose of this paper is to study the structure of the tensor product spaces $ X{ \otimes _\varepsilon }Y$ $ X{ \otimes _\pi }Y$ $ ({x_i} \otimes {y_j})$ of such bases.