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The widely expressed G-protein coupled receptors (GPCRs) are versatile signal transducer proteins that are attractive drug targets but structurally challenging to study. GPCRs undergo a number of conformational rearrangements when transitioning from the inactive to the active state but have so far been believed to adopt a fairly conserved inactive conformation. Using 19 F NMR spectroscopy and advanced molecular dynamics simulations we describe a novel inactive state of the adenosine 2A receptor which is stabilised by the aminotriazole antagonist Cmpd-1. We demonstrate that the ligand stabilises a unique conformation of helix V and present data on the putative binding mode of the compound involving contacts to the transmembrane bundle as well as the extracellular loop 2., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Silica-supported AgNO 3 (AgNO 3 -SiO 2 ) catalyzes the dearomatizing spirocyclization of alkyne-tethered aromatics far more effectively than the analogous unsupported reagent; in many cases, reactions which fail using unsupported AgNO 3 proceed effectively with AgNO 3 -SiO 2 . Mechanistic studies indicate that this is a consequence of silver nanoparticle formation on the silica surface combined with a synergistic effect caused by the silica support itself. The remarkable ease with which the reagent can be prepared and used is likely to be of much synthetic importance, in particular, by making nanoparticle catalysis more accessible to non-specialists., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Indolyl α-diazocarbonyls can be selectively cyclized to give six distinct products through the careful choice of catalyst and reaction conditions. A range of catalysts were used, including complexes of Rh(II) , Pd(II) , and Cu(II) , as well as SiO2 , to promote diazo decomposition and subsequent cyclization/rearrangement through a range of mechanistic pathways., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A high-yielding silver(I)- or copper(II)-catalyzed dearomatizing spirocyclization strategy allows the conversion of simple aromatic compounds that contain ynone substituents, including indole, anisole, pyrrole, and benzofuran derivatives, into functionalized spirocyclic scaffolds. A high-yielding asymmetric variant furnishes spirocyclic indolenines in up to 89:11 e.r., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Collision cross-sections (CCS) of immunoglobulins G1 and G4 have been determined using linear drift-tube ion-mobility mass spectrometry. Intact antibodies and Fc-hinge fragments present with a larger range of CCS than proteins of comparable size. This is rationalized with MD simulations, which indicate significant in vacuo dynamics between linked folded domains. The IgG4 subclass presents over a wider CCS range than the IgG1 subclass., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The amount of research activity concerning alpha-methylene-gamma-butyrolactones and alpha-alkylidene-gamma-butyrolactones has increased dramatically in recent years. This Review summarizes the structural types, biological activities, and biosynthesis of these compounds, concentrating on publications from the past 10 years. Traditional approaches to alpha-methylene-gamma-butyrolactones and alpha-alkylidene-gamma-butyrolactones are then reviewed together with novel approaches, including those from our own research group, reported more recently.

Polysubstituted cyclopentanes from readily available starting materials? A versatile anionic [3+2] approach is offered by the reaction of difunctional organolithium reagents 1 with alkenes 2 in a tandem intermolecular - intramolecular carbolithiation (see scheme). This convergent sequence is especially attractive as, not only are the precursors readily available, but the products provide valuable synthetic building blocks.

Readily available S-glycoside dioxides were utilized in a Ramberg-Bäcklund rearrangement for the construction of C-linked disaccharides. This approach is ideally suited to analogue synthesis simply by variation of the alkylating agent, and is illustrated here by the synthesis of beta,beta-C-trehalose (see reaction scheme), a higher homologue of C-trehalose, and methyl C-gentiobioside. Bn=benzyl.