Studies on Heteroaromaticity. XXI. 1,3-Dipolar Cycloaddition of<i>N</i>-Phenyl-<i>C</i>-(6-uracilyl)nitrone
作者:Tadashi Sasaki、Moriyasu Ando
DOI:10.1246/bcsj.41.2960
日期:1968.12
N-Phenyl-C-(6-uracilyl)nitrone (II) was prepared in 80% yield from orotaldehyde (I) and phenylhydroxylamine. II underwent 1,3-dipolar cycloaddition reactions with several ethylenic and acetylenic compounds to afford the corresponding isoxazolidines (IIIa—f) and isoxazolines (IVg—i). Similar reactions of II with phenyl isocyanate, carbon disulfide and with enamine were carried out successfully. The structural elucidation of these products was done on the basis of their NMR spectra.
Synthesis and biological activity of a new class of cytotoxic agents: N-(3-oxoprop-1-enyl)-substituted pyrimidines and purines
作者:Francis Johnson、K. M. R. Pillai、Arthur P. Grollman、Lucy Tseng、Masaru Takeshita
DOI:10.1021/jm00374a004
日期:1984.8
thymine and adenine compounds are highly cytotoxic to a variety of tumor cell lines and inhibit macromolecular synthesis in cultured HeLa cells. Structure-activity studies, based primarily on the pyrimidine derivatives, reveal that the most potent inhibition occurs when the propenal group is located on the 3-nitrogen of a 2'-deoxyribonucleoside. The 3-(3-oxoprop-1-enyl) derivatives of thymidine, 2'-deoxyuridine
A simple and efficient synthesis of cyclopentadienones via palladium-catalyzed cyclocarbonylation of alkynes under atmosphericpressure of carbonmonoxide has been developed. The transformation was carried out under mild and ligand-free conditions, a wide range of substrates and exceptional functional group tolerance.
Synthesis and antimalarial activities of base-catalyzed adducts of 11-azaartemisinin
作者:Belew Mekonnen、Everett Weiss、Esther Katz、Jingyuan Ma、Herman Ziffer、Dennis E Kyle
DOI:10.1016/s0968-0896(00)00049-3
日期:2000.5
to an amide nitrogen of olefins and terminal acetylenesconjugated with electron withdrawing groups (EWGs). When the terminal acetylene was conjugated with carbomethoxy, N,N-dimethyl amide or carbonyl groups, the E-adducts resulted. A mixture of E- and Z-adducts were obtained when the EWG was a nitrile. In vitro antimalarial activities of each compound were determined against two drug-resistant strains
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.