Resolution-Enhanced Kendrick Mass Defect Analysis of Polycyclic Aromatic Hydrocarbons and Fullerenes in the Diffusion Flame from a Butane Torch

A modified Kendrick Mass Defect (KMD) analysis was applied to the analysis of polycyclic aromatic hydrocarbons (PAHs) and fullerenes in the diffusion flame from a handheld butane torch.

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A ‘click chemistry’ approach to the efficient synthesis of modified nucleosides and oligonucleotides for PET imaging

Different thymidine derivatives bearing either an iodoaryl moiety at the 5′ position or a dialkylsilyl group at the 3′ position have been efficiently synthesized as precursors for carbon-11 or fluorine-18 labeling, respectively. Furthermore, iodoarylated thymidine derivatives have been incorporated into oligonucleotides giving an original way to label them with carbon-11.     

NMR of human saliva protein/wine tannin complexes. Towards deciphering astringency with physico-chemical tools

In the present work, we used NMR (chemical shift variations and diffusion measurement) to determine the affinity and the number of sites of four different 4-8 procyanidin dimers for a model PRP peptide. A number of three binding sites has been identified for every tannin, but significant affinity differences are highlighted from one to another dimer (a factor 10 approximately) that could be related to their specific 3D-structure.     

On (Kq,k) vertex stable graphs with minimum size

A graph $G$ is a $(K_q,k)$ vertex stable graph if it contains a $K_q$ after deleting any subset of $k$ vertices. We give a characterization of $(K_q,k)$ vertex stable graphs with minimum size for $q=3,4,5$.     

Synthesis of indanones by sequential Heck-reduction–cyclization–alkylation (HRCA) reactions

A simple and efficient synthesis of indanones, bearing a quaternary carbon centre, has been developed. The method features, in a one-pot process, the use of a multi-task palladium catalyst for the sequential Heck-reduction reactions, followed by a base-mediated cyclization–alkylation sequence. This methodology, called Heck-reduction–cyclization–alkylation (HRCA), is carried out under mild and simple experimental conditions with the use of inexpensive reagents. The mild conditions have been made possible by the use of diazonium salts that allow Heck couplings at moderate temperature (40 °C) under ligand-free conditions.     

Low energy spin dynamics in the spin ice Ho2Sn2O7

The magnetic properties of Ho(2)Sn(2)O(7) have been investigated and compared to other spin ice compounds. Although the lattice has expanded by 3% relative to the better studied Ho(2)Ti(2)O(7) spin ice, no significant changes were observed in the high temperature properties, T is more or approximately equal to 20 K. As the temperature is lowered and correlations develop, Ho(2)Sn(2)O(7) enters its quantum phase at a slightly higher temperature than Ho(2)Ti(2)O(7) and is more antiferromagnetic in character. Below 80 K a weak inelastic mode associated with the holmium nuclear spin system has been measured. The hyperfine field at the holmium nucleus was found to be ≈700 T.     

Stille cross-coupling of activated alkyltin reagents under "ligandless" conditions

Monoalkyltins activated by a fluoride source are shown to be as reactive as their vinyl or aryl homologues in the Stille coupling reaction, thus providing an easy entry into the pallado-catalyzed formation of Csp3-Csp2 bonds. In addition to this uncommon reactivity, this methodology holds several advantages such as (i) a quantitative preparation of stable and easy to handle alkyltin reagents 2, (ii) a simplified coupling procedure without any phosphine added ligand under neutral conditions, and (iii) a facile purification step of the organic products from the inorganic nontoxic tin byproducts.