Conformational analogs of antihypertensive agents related to guanethidine
摘要:
In an effort to clarify the conformational requirements, if any, of agents producing adrenergic neuronal blockade through mechanisms similar to guanethidine, the synthesis and pharmacological evaluation of 15 analogues of cinnamylguanidine are described. These analogues represent derivatives in which the distance between the center of the ring system and the guanidinium nitrogen atom varies from 3.9 to 6.2 A. While conformational relationships could not be defined in this study, three analogues (3, 4, and 5) were apparently more potent than guanethidine in the in vitro assay employed.
The propargyltitanium reagents derived from 1-alkylpropyne condensed with aldehydes to give α-allenyl alcohol regioselectively, while the allenyltitanium reagents generated from 1-alky1-1-butyne derivatives gave threo-β-acetylenic alcohols with high regio- and stereoselectivities. The course of the reaction was determined by the substitution pattern of starting alkynes. The similar reactions of metallated
The photomediated reaction of alkynes with cycloalkanes
作者:Roísín A. Doohan、John J. Hannan、Niall W. A. Geraghty
DOI:10.1039/b517631j
日期:——
of a photomediator such as benzophenone, alkynes with electron-withdrawing groups react with cycloalkanes to give vinyl cycloalkanes. The reaction involves the regiospecific addition of a photochemically generated cycloalkyl radical to the beta-carbon of the alkyne. The stereochemical outcome of the reaction depends on the nature of the photomediator and alkyne used.
[EN] PROCESS FOR HYDROCYANATION OF TERMINAL ALKYNES<br/>[FR] PROCÉDÉ D'HYDROCYANATION D'ALCYNES TERMINAUX
申请人:STUDIENGESELLSCHAFT KOHLE MBH
公开号:WO2018210631A1
公开(公告)日:2018-11-22
The present invention refers to a process for a Rh-catalyzed Anti-Markovnikov hydrocyanation of terminal alkynes which process discloses, for the first time, the highly stereo- and regio-selective hydrocyanation of terminal alkynes to furnish E- configured alkenyl nitriles and the catalyst used in the present process.
Part I: The Development of the Catalytic Wittig Reaction
作者:Christopher J. O'Brien、Zachary S. Nixon、Andrew J. Holohan、Stephen R. Kunkel、Jennifer L. Tellez、Bryan J. Doonan、Emma E. Coyle、Florie Lavigne、Lauren J. Kang、Katherine C. Przeworski
DOI:10.1002/chem.201301444
日期:2013.11.4
developed the first catalytic (in phosphane) Wittigreaction (CWR). The utilization of an organosilane was pivotal for success as it allowed for the chemoselective reduction of a phosphane oxide. Protocol optimization evaluated the phosphane oxide precatalyst structure, loading, organosilane, temperature, solvent, and base. These studies demonstrated that to maintain viable catalytic performance it was
Rh-Catalyzed Anti-Markovnikov Hydrocyanation of Terminal Alkynes
作者:Fei Ye、Junting Chen、Tobias Ritter
DOI:10.1021/jacs.7b03749
日期:2017.5.31
We report the first highly stereo- and regioselective hydrocyanation of terminal alkynes to furnish E-configured alkenyl nitriles. Acrylonitriles can be accessed on gram scale with broad substrate scope and functional group tolerance. The hydrocyanation reaction employs acetone cyanohydrin as a practical alternative to HCN gas.
我们报告了第一个高度立体和区域选择性的末端炔烃氢氰化反应,以提供 E 构型的烯基腈。丙烯腈可以在克级获得,具有广泛的底物范围和官能团耐受性。氢氰化反应使用丙酮氰醇作为 HCN 气体的实用替代品。