Two successful synthetic routes to trichostatin A (1) are described; one (Scheme 2) uses the γ-alkylation of a silyl dienol ether, the other (Scheme 4) uses a silyl-protected cyanohydrin anion. The two routes bear an upolung relation to each other. The Lewis acid-catalysed acylation of silyl enol ethers is a simple and effective way to prepare β-diketones and β-keto esters (Scheme 1); this reaction
Regio- and Stereoselective Monoepoxidation of Dienes using Methyltrioxorhenium: Synthesis of Allylic Epoxides
作者:Saroj Ranjan De、Ganesh Kumar、Jawahar L. Jat、Saritha Birudaraju、Biao Lu、Rajkumar Manne、Narender Puli、Adeniyi Michael Adebesin、John R. Falck
DOI:10.1021/jo501958d
日期:2014.11.7
Methyltrioxorhenium (MTO) complexed with pyridine was shown to be a highly effective catalyst for the regioselective monoepoxidation of conjugateddi- and trienes using 30% H2O2 at or below room temperature. The resultant allylic epoxides, and the triols derived from them, are versatile synthetic intermediates as well as substructures present in many bioactive natural products. The site of epoxidation
与吡啶络合的甲基三氧铼 (MTO) 被证明是在室温或低于室温下使用 30% H 2 O 2对共轭二烯和三烯进行区域选择性单环氧化的高效催化剂。由此产生的烯丙基环氧化物和由它们衍生的三醇是通用的合成中间体以及存在于许多生物活性天然产物中的亚结构。环氧化位点取决于烯烃取代、烯烃几何形状(Z与E),以及相邻碳原子上存在吸电子取代基。对于 1-酰基(甲硅烷基)氧基五-2,4-二烯,与 Sharpless、过酸和羟基化二烯的其他定向环氧化的相邻区域选择性特征相比,通常有利于远端烯烃的环氧化。
Thrombin receptor antagonists
申请人:——
公开号:US20040152736A1
公开(公告)日:2004-08-05
A series of compounds represented by the structural formulas
1
2
and pharmaceutically acceptable isomers, salts, solvates and polymorphs thereof are disclosed. Also disclosed are pharmaceutical compositions containing said compounds and their use as thrombin receptor antagonists and binders to cannabinoid receptors.
Derivatives of hexahydrobenzofuranone useful for the treatment of (inter alia) auto-immune or inflammatory disorders
申请人:Merck Sharp & Dohme Corp.
公开号:EP2301930B1
公开(公告)日:2016-01-06
Highly Regio- and Enantioselective Monoepoxidation of Conjugated Dienes
作者:Michael Frohn、Molly Dalkiewicz、Yong Tu、Zhi-Xian Wang、Yian Shi
DOI:10.1021/jo9721195
日期:1998.5.1
This paper describes a highly effective and mild asymmetric monoepoxidation method for conjugated dienes using a fructose-derived chiral ketone 1 as catalyst and Oxone as oxidant. The regioselectivies and enantioslectivies are very high in most cases. For unsymmetrical dienes, the regioselectivity can be regulated by using steric and electronic control. The olefin substrates include trans-disubstituted and trisubstituted olefins that can bear a wide range of functional groups such as hydroxyl groups, TBS ethers, or esters. The enantiomeric excesses for the major monoepoxides range from 89% to 97%. The epoxidation is believed to proceed via a spiro mode.