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A facile synthesis of novel 1,2,6,7-tetrahydro-3H-pyrazolo[4,3-c]pyridine-3,4(5H)-diones has been achieved. The operationally simple procedure, using readily available intermediates, allows for rapid derivatisation of the pharmacophore with alkyl, aryl and heteroaryl substituents. 相似文献
944.
You-Lin Xue Qiaoshi Zhang Yuna Sun Xiaohong Zhou Ian P. Hurley Gary W. Jones Youtao Song 《Journal of computer-aided molecular design》2018,32(11):1217-1227
Genetics experiments have identified six mutations located in the subdomain IA (A17V, R23H, G32D, G32S, R34K, V372I) of Ssa1 that influence propagation of the yeast [PSI+] prion. However, the underlining molecular mechanisms of these mutations are still unclear. The six mutation sites are present in the IA subdomain of the nucleotide-binding domain (NBD). The ATPase subdomain IA is a critical mediator of inter-domain allostery in Hsp70 molecular chaperones, so the mutation and changes in this subdomain may influence the function of the substrate-binding domain. In addition, ADP release is a rate-limiting step of the ATPase cycle and dysregulation of the ATPase cycle influences the propagation of the yeast [PSI+] prion. In this work, steered molecular dynamics (SMD) simulations were performed to explore the interaction between ADP and NBD. Results suggest that during the SMD simulations, hydrophobic interactions are predominant and variations in the binding state of ADP within the mutants is a potential reason for in vivo effects on yeast [PSI+] prion propagation. Additionally, we identify the primary residues in the ATPase domain that directly constitute the main hydrophobic interaction network and directly influence the ADP interaction state with the NBD of Ssa1. Furthermore, this in silico analysis reaffirms the importance of previously experimentally-determined residues in the Hsp70 ATPase domain involved in ADP binding and also identifies new residues potentially involved in this process. 相似文献
945.
Shorouk O. Badir Audrey Dumoulin Jennifer K. Matsui Prof. Gary A. Molander 《Angewandte Chemie (International ed. in English)》2018,57(22):6610-6613
The incorporation of C‐glycosides in drug design has become a routine practice for medicinal chemists. These naturally occurring building blocks exhibit attractive pharmaceutical profiles, and have become an important target of synthetic efforts in recent decades. 1 Described herein is a practical, scalable, and versatile route for the synthesis of non‐anomeric and unexploited C‐acyl glycosides through a Ni/photoredox dual catalytic system. By utilizing an organic photocatalyst, a range of glycosyl‐based radicals are generated and efficiently coupled with highly functionalized carboxylic acids at room temperature. Distinctive features of this transformation include its mild conditions, impressive compatibility with a wide array of functional groups, and most significantly, preservation of the anomeric carbon: a handle for further, late‐stage derivatization. 相似文献
946.
Sy D. Friedman W. Hugh Woodin 《Proceedings of the American Mathematical Society》1996,124(7):2211-2213
We show that the supremum of the lengths of prewellorderings of the reals can be , with inaccessible to reals, assuming only the consistency of an inaccessible.
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Gallas E Abolins M Brock R Cobau WG Hatcher RW Owen DP Perkins GJ Tartaglia M Weerts H Bogert D Fuess S Koizumi G Stutte L Friedman JI Kendall HW Kistiakowsky V Lyons T Osborne LS Pitt R Rosenson L Schneekloth U Strongin B Taylor FE Walker JK White A Womersley WJ 《Physical review D: Particles and fields》1995,52(1):6-14