Synthesis of Alkenylboronates from <i>N</i>-Tosylhydrazones through Palladium-Catalyzed Carbene Migratory Insertion
作者:Yifan Ping、Rui Wang、Qianyue Wang、Taiwei Chang、Jingfeng Huo、Ming Lei、Jianbo Wang
DOI:10.1021/jacs.1c02331
日期:2021.7.7
The palladium-catalyzed oxidative borylation reaction of N-tosylhydrazones has been developed. The reaction features mild conditions, broad substratescope, and good functional group tolerance. It thus represents a highly efficient and practical method for the synthesis of di-, tri-, and tetrasubstituted alkenylboronates from readily available N-tosylhydrazones. One-pot Suzuki coupling and other transformations
Description anti-mitotic agents which inhibit tubulin polymerization
申请人:Baylor University
公开号:US06350777B2
公开(公告)日:2002-02-26
Methoxy and ethoxy substituted 3-aroyl-2-arylbenzo[b]thiophenes and benzo[b]thiophene analogues are described for use in inhibiting tubulin polymerization. The compounds' use for treating tumor cells is also described.
Additional aspects described here are certain diaryl ether benzo[b]thiophene derivatives. Also described are particular analogs derived from dihydronaphthalene which have proven particularly effective. Certain new benzofuran analogs are described, as well as certain sulfur oxide benzo[b]thiophene analogs.
Important compounds described herein include the first nitrogen-containing derivatives of combretastatin. These include nitro, amino and azide combrdtastatin derivatives.
NNNifty targets: In a straightforward copper‐mediated synthesis of 1,4‐disubstituted and 1,4,5‐trisubstituted 1,2,3‐triazoles, readily available aniline and N‐tosylhydrazone substrates underwent cyclization through CN and NN bond formation (see scheme; Piv=pivaloyl, Ts=p‐toluenesulfonyl). This method enables the preparation of 1,2,3‐triazoles with high efficiency under mild conditions without the
bromides. The reaction proceeds efficiently when a combination of a highly substituted bromoalkene and a hydrazone derived from a ketone are employed, pointing to the convenience of a stericallyencumbered environment. This unprecedented process allows for the stereocontrolled preparation of highly substituted dienes and polyenes.
Regioselective One-Step Synthesis of Pyrazoles from Alkynes and N-Tosylhydrazones: [3+2] Dipolar Cycloaddition/[1,5] Sigmatropic Rearrangement Cascade
作者:M. Carmen Pérez-Aguilar、Carlos Valdés
DOI:10.1002/anie.201301284
日期:2013.7.8
Rearrangement under control: A wide variety of 3,4,5‐ and 1,3,5‐trisubstituted pyrazoles can be prepared from tosylhydrazones of ketones and terminal alkynes through the title reaction sequence (see scheme; Ts=4‐toluenesulfonyl). The rearrangement, and therefore, the regioselectivity of the reaction is controlled by the nature of the substituents of the tosylhydrazone.