四氢吡喃基(THP)醚与三乙基甲硅烷基三氟甲磺酸盐(TESOTf)–2,4,6-可力丁的反应通过胶体盐中间体进行,以高收率得到了醇和4-三乙基甲硅烷氧基丁醛。中间体的结构由1确定1 H NMR和FAB-MS研究并通过用EtOH捕获。该反应用于THP醚的温和,高效和高度化学选择性的脱保护方法。该反应的特征是反应条件是弱碱性的。然后,可以在不影响酸不稳定的保护基的情况下进行反应。此外,将烯醇-THP醚的中间体与其他烯醇截留,得到无环的混合缩醛,然后以四氢吡喃基单元为系绳,进行有效的闭环复分解。
General Strategy for the Synthesis of B<sub>1</sub> Phytoprostanes, Dinor Isoprostanes, and Analogs
作者:Annika Schmidt、Wilhelm Boland
DOI:10.1021/jo062359x
日期:2007.3.1
The synthesis of the phytoprostane B1 types I and II is achieved in high overall yield (35−53%) by only two principal transformations starting from 1,3-cyclopentanedione. The first side chain is attached via O-acylation of the 1,3-dione followed by rearrangement and reduction to give the 2-alkyl-1,3-diones 4a−c. After conversion into the corresponding vinylic iodides 5a−c, the second side chain is
Synthesis of 2-(1-Phosphorylalkyl)- and 2-(1-Alkenyl)furans through Nitrile Oxide Cycloaddition Route
作者:Otohiko Tsuge、Shuji Kanemasa、Hiroyuki Suga
DOI:10.1246/bcsj.61.2133
日期:1988.6
A new synthetic method of 2-(1-phosphorylalkyl)furans with a variety of substituents on the ring is presented. Cycloaddition of (diethoxyphosphoryl)acetonitrile oxide to O-protected allyl alcohols is followed by a simple sequential procedure including Raney Ni reduction and acid treatment to give 2-(1-phosphorylmethyl)furans. The phosphorus-stabilized carbanions derived from the phosphorus-functionalized furans are applied to alkylation, oxidation with oxygen, or olefination to provide 2-(1-phosphorylalkyl)furans, 2-acylfurans, or 2-(1-alkenyl)furans, respectively. Some other synthetic applications are also described.
Ketosynthase (KS) domains of modular typeIpolyketidesynthases (PKSs) typically catalyze the Claisen condensation of acyl and malonyl units to form linear chains. In stark contrast, the KS of the rhizoxin PKS branching module mediates a Michael addition, which sets the basis for a pharmacophoric δ‐lactone moiety. The precise role of the KS was evaluated by site‐directed mutagenesis, chemical probes
Neue fluorhaltige Prostaglandinderivate, Verfahren zu ihrer Herstellung und ihre Verwendung als Arzneimittel
申请人:HOECHST AKTIENGESELLSCHAFT
公开号:EP0001255B1
公开(公告)日:1981-09-30
Reaction of Tetrahydropyranyl Ethers with Triethylsilyl Trifluoromethanesulfonate–2,4,6-Collidine Combination: Speculation on the Intermediate, Efficient Deprotection, and Application to Efficient Ring-Closing Metathesis as a Tether
作者:Hiromichi Fujioka、Takashi Okitsu、Takuya Ohnaka、Yoshinari Sawama、Ozora Kubo、Kazuhisa Okamoto、Yasuyuki Kita
DOI:10.1002/adsc.200600572
日期:2007.3.5
chemoselective deprotection method of THP ethers. The characteristic feature of the reaction is that the reaction conditions are weakly basic. Then, the reaction can proceed without affecting acid-labile protecting groups. Furthermore, the intermediates from alkenol–THP ether were trapped with other alkenols to give acyclic mixed acetals, which were subjected to efficient ring-closing metathesis by using the
四氢吡喃基(THP)醚与三乙基甲硅烷基三氟甲磺酸盐(TESOTf)–2,4,6-可力丁的反应通过胶体盐中间体进行,以高收率得到了醇和4-三乙基甲硅烷氧基丁醛。中间体的结构由1确定1 H NMR和FAB-MS研究并通过用EtOH捕获。该反应用于THP醚的温和,高效和高度化学选择性的脱保护方法。该反应的特征是反应条件是弱碱性的。然后,可以在不影响酸不稳定的保护基的情况下进行反应。此外,将烯醇-THP醚的中间体与其他烯醇截留,得到无环的混合缩醛,然后以四氢吡喃基单元为系绳,进行有效的闭环复分解。