Ring-closing metathesis for the synthesis of benzo-fused bicyclic compounds
作者:Willem A.L. van Otterlo、E.Lindani Ngidi、E.Mabel Coyanis、Charles B. de Koning
DOI:10.1016/s0040-4039(02)02522-4
日期:2003.1
Ring-closing metathesis (RCM) was used to synthesise five 4H-chromenes, a naphthol and an indenol. These are the first examples of RCM applied to the synthesis of such benzo-fusedbicyclic compounds.
general, and functional group tolerant intramolecular hydroalkoxylation and hydroacyloxylation of unactivated olefins using a Co(salen) complex, an N-fluoropyridinium salt, and a disiloxane reagent is described. This reaction was carried out at room temperature and afforded five- and six-membered oxygen heterocyclic compounds, such as cyclic ethers and lactones. The Co complex was optimized for previously
描述了使用 Co(salen) 配合物、N-氟吡啶鎓盐和二硅氧烷试剂对未活化烯烃进行温和、通用和官能团耐受的分子内加氢烷氧基化和加氢酰氧基化。该反应在室温下进行,得到五元和六元氧杂环化合物,如环醚和内酯。通过未活化烯烃的加氢官能化,Co 配合物针对先前稀有介质环的形成进行了优化。强大的 Co 催化剂体系还可以使 O-保护的链烯醇脱保护加氢烷氧基化和链烯基酯加氢酰氧基化,直接得到环醚和内酯。研究了脱保护的底物范围和机理证明。
Towards an asymmetric synthesis of the bacterial peptide deformylase (PDF) inhibitor fumimycin
作者:Caroline E. Hartmann、Patrick J. Gross、Martin Nieger、Stefan Bräse
DOI:10.1039/b916372g
日期:——
Studies towards the synthesis of the bacterial peptide deformylase (PDF) inhibitor fumimycin are reported. The synthetic approach features an organocatalytic access to the α,α-disubstituted amino acid unit and results in the synthesis of an advanced intermediate which already contains all functionalities of fumimycin.
The human CYP2A6 enzyme metabolizes several xenobiotics including nicotine, the addictive component in tobacco. Reduced activity of CYP2A6, either for genetic reasons or by administering inhibitors of CYP2A6, reduces tobacco smoking. The reported compound methoxalen had a potent inhibitory effect on activity of CYP2A6 with an IC50 value of 1.27 mu M. We selected methoxalen as a lead compound and prepared various dimethoxybenzofuran derivatives that have inhibitory effects on activity of human cytochrome P450 (CYP) 2A6. Synthetic benzofuran derivatives (3,6-dimethoxybenzofuran: IC50=1.92 mu M and 3,7-dimethoxybenzofuran: IC50=2.00 mu M) also exhibited comparable activities against CYP2A6 and were selective inhibitors of CYP2A6. These compounds can be used as lead compounds in the development of drugs for smoking reduction therapy.
Ring-closing metathesis for the synthesis of 2H- and 4H-chromenes
作者:Willem A.L. van Otterlo、E. Lindani Ngidi、Samuel Kuzvidza、Garreth L. Morgans、Simon S. Moleele、Charles B. de Koning
DOI:10.1016/j.tet.2005.08.020
日期:2005.10
Six 4H-chromenes were synthesized from substituted phenols using vinylstannylation and ring-closing metathesis (RCM) as key steps. In addition, a different approach involving amongst other steps, an aryl allyl isomerization and RCM afforded a set of seven 2H-chromenes from phenolic precursors. (c) 2005 Elsevier Ltd. All rights reserved.