Synthesis and reduction reactions of pyridones and 5-acyl-2-methoxypyridines
摘要:
The synthesis of a series of pyridones, from their 2-hydroxypyridine or 2-methoxypyridine precursors, is described, along with studies into their reductions to saturated heterocycles. A number of 5-acylpyridones were prepared and were evaluated as substrates for asymmetric transfer hydrogenation prior to conversion to saturated heterocycles. The enantioselective reduction of 5-acetyl-1-benzylpyrimidine-2,4(1H,3H)-dione is also described. (C) 2014 Elsevier Ltd. All rights reserved.
Synthesis and reduction reactions of pyridones and 5-acyl-2-methoxypyridines
摘要:
The synthesis of a series of pyridones, from their 2-hydroxypyridine or 2-methoxypyridine precursors, is described, along with studies into their reductions to saturated heterocycles. A number of 5-acylpyridones were prepared and were evaluated as substrates for asymmetric transfer hydrogenation prior to conversion to saturated heterocycles. The enantioselective reduction of 5-acetyl-1-benzylpyrimidine-2,4(1H,3H)-dione is also described. (C) 2014 Elsevier Ltd. All rights reserved.
The present invention relates to methods for generating mature insulin-producing β-like cells comprising the steps: (a) isolating, purifying and/or enriching β-cell progenitor cells from a population of cells; (b) differentiation of the β-cell progenitor cells into immature insulin-producing β-like cells; and (c) maturation of the immature insulin-producing β-like cells into mature insulin-producing β-like cells, comprising exposing the immature insulin-producing β-like cells to calcitriol or an analogue thereof. More particularly, the present invention relates to methods for generating mature insulin-producing β-like cells for use in treating diabetes.
We demonstrate a ligand- and glovebox-free regioselective direct C(3)–H imidation of 2-pyridones and also benzylic-type imidation of 2-pyridones bearing a methyl substituent employing Cu(OAc)2·H2O as the catalyst and N-fluorobenzenesulfonimide (NFSI) as an imidating reagent. A broad range of imidated 2-pyridone derivatives is made up to excellent yields. The present strategy operates well on a gram
An annulation method for the synthesis of alkyl-substituted 6-carbomethoxy-2-pyridones
作者:Yu Zhang、Brad M. Loertscher、Steven L. Castle
DOI:10.1016/j.tet.2009.06.006
日期:2009.8
A protocol for the synthesis of 5-alkyl and 3,5-dialkyl-6-carbomethoxy-2-pyridones was devised. Key steps include a Mannich reaction, acylation of a tosylamine, and a PPh3/TiCl4-promoted intramolecular Reformatsky-type reaction with a thioester as the electrophile. The latter process typically afforded a vinylogous thiocarbamate via elimination of water rather than the Dieckmann-type product which would have resulted from elimination of the thiol. However, the Dieckmann-type ketone product was obtained in one instance. Subsequent elimination of the tosyl group and desulfurization completed the pyridone synthesis. (C) 2009 Elsevier Ltd. All rights reserved.
Ligand-Controlled Ni(0)–Al(III) Bimetal-Catalyzed C3–H Alkenylation of 2-Pyridones by Reversing Conventional Selectivity
作者:Ge Yin、Yue Li、Rong-Hua Wang、Jiang-Fei Li、Xue-Tao Xu、Yu-Xin Luan、Mengchun Ye