Topoisomerase inhibitors are potent DNA damaging agents which are widely used in oncology, and they demonstrate robust synergistic tumor cell killing in combination with DNA repair inhibitors, including poly(ADP)-ribose polymerase (PARP) inhibitors. However, their use has been severely limited by the inability to achieve a favorable therapeutic index due to severe systemic toxicities. Antibody-drug conjugates address this issue via antigen-dependent targeting and delivery of their payloads, but this approach requires specific antigens and yet still suffers from off-target toxicities.
View Article and Find Full Text PDFObjectives: The visibility of the pink ball used in day/night Test cricket has been under scrutiny, with recent research suggesting cricketers find the pink ball less visible at dusk under floodlights. With increasing interest in this match format, this study sought to investigate elite umpires' opinions pertaining to the visibility of the pink cricket ball during day/night matches.
Design: Purposeful sampling of a cross-section of elite umpires with experience adjudicating matches played using a pink cricket ball.
Objectives: Cricket administrators have started scheduling long-form matches which finish at night and are played with a pink as opposed to a red ball. However, there are reports that the pink ball may introduce new dangers and alter performance. The aim of this study was to investigate professional cricketers' opinions about the visibility of the pink ball whilst playing in different lighting conditions (afternoon, dusk and night).
View Article and Find Full Text PDFWe herein report the development of a conformationally defined, electron-rich, C -symmetric, P-chiral bisphosphorus ligand, ArcPhos, by taking advantage of stereoelectronic effects in ligand design. With the Rh-ArcPhos catalyst, excellent enantioselectivities and unprecedentedly high turnovers (TON up to 10 000) were achieved in the asymmetric hydrogenation of aliphatic carbocyclic and heterocyclic tetrasubstituted enamides, to generate a series of chiral cis-2-alkyl-substituted carbocyclic and heterocyclic amine derivatives in excellent enantiomeric ratios. This method also enabled an efficient and practical synthesis of the Janus kinase inhibitor (R)-tofacitinib.
View Article and Find Full Text PDFGlucokinase activators are a class of experimental agents under investigation as a therapy for Type 2 diabetes mellitus. An X-ray crystal structure of a modestly potent agent revealed the potential to substitute the common heterocyclic amide donor-acceptor motif for a pyridone moiety. We have successfully demonstrated that both pyridone and pyrimidone heterocycles can be used as a potent donor-acceptor substituent.
View Article and Find Full Text PDFCompound 4 (PF-04971729) belongs to a new class of potent and selective sodium-dependent glucose cotransporter 2 inhibitors incorporating a unique dioxa-bicyclo[3.2.1]octane (bridged ketal) ring system.
View Article and Find Full Text PDFModifications to the sugar portion of C-aryl glycoside sodium glucose transporter 2 (SGLT2) inhibitors were explored, including systematic deletion and modification of each of the glycoside hydroxyl groups. Based on results showing activity to be quite tolerant of structural change at the C-5 position, a series of novel C-5 spiro analogues was prepared. Some of these analogues exhibit low nanomolar potency versus SGLT2 and promote urinary glucose excretion (UGE) in rats.
View Article and Find Full Text PDFA suitable inhibitor of activated thrombin activatable fibrinolysis inhibitor (TAFIa) has the potential to be a novel treatment for thrombosis. The TAFIa inhibitor UK-396082 (1) was used as a starting point to seek more potent analogues. With knowledge of encouraging human pharmacokinetics and toleration for the clinical candidate (1), the programme continued to seek structure-activity relationships (SAR) that could positively impact on both potency and half-life, and therefore the projected dose of any future nominated clinical agent.
View Article and Find Full Text PDFA series of allyl bromides bearing an ethereal stereogenic substituent at C-2 were synthesized from methyl acrylate. These were coupled with a range of aldehydes under chromium(II) chloride-mediated conditions to afford syn-4-alkoxyalkan-1-ols in good yield and diastereoselectivity. The effect of altering the nature of the ethereal group and alkyl substituent upon the diastereoselectivity of the reaction was also investigated.
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