60682-83-9Relevant academic research and scientific papers
Substituent-controlled annuloselectivity and stereoselectivity in the sulfa-Staudinger cycloadditions
Yang, Zhanhui,Chen, Ning,Xu, Jiaxi
, p. 3611 - 3620 (2015/04/22)
In the sulfa-Staudinger cycloadditions of imines and sulfonyl chlorides, the annuloselectivity is mainly controlled by the electronic effect of the α-substituents of sulfonyl chlorides and the nucleophilicity of imines. Sulfonyl chlorides with weakly elec
Synthesis and Antineoplastic Activity of Bisoxy>methyl>-Substituted 3-Pyrrolines as Prodrugs of Tumor Inhibitory Pyrrole Bis(carbamates)
Anderson, Wayne K.,Milowsky, Arnold S.
, p. 2241 - 2249 (2007/10/02)
A series of bispyrrolines 2-4 were synthesized from either the appropriate α-silylated iminium salt, or an aziridine, or a 2H-azirine in a sequence involving 1,3-dipolar cycloaddition reactions.The antineoplastic activities of the pyrrolines were compared to the corresponding pyrroles.The C-2 gem-dimethyl-substituted pyrroline, 4, which cannot be converted to the pyrrole in vivo, was inactive.The activity of the 2-phenyl-substituted pyrrolines 3 was markedly dependent on the nature of the phenyl substituent, although the correspondingphenylpyrroles all showed comparable activity.The differences in the activities of the pyrrolines 3 may be due to the rate of metabolic conversion of the pyrroline to the pyrrole.Electron-withdrawing substituents on the phenyl ring appear to retard this process.
Relative Conjugative Abilities of Three-Membered Ring Heterocycles with Benzene Based on 13C and 15N NMR
Crist, DeLanson R.,Jordan, Guy J.,Moore, Donald W.,Hashmall, Joseph A.,Borsetti, Arnold P.,Turujman, Saleh A.
, p. 4136 - 4142 (2007/10/02)
The conjugative ability of various three-membered rings with benzene was investigated by observing the sensitivity of β-carbon 13C chemical shifts to para substituents.These Hammett ρ values were 2.0, 1.5, 1.0, and 0.9 ppm for arylcyclopropanes, N-methyl-2-arylaziridines, phenyloxiranes, and N,N-dimethyl-2-arylaziridinium fluorosulfonates, respectively.These values were intermediate to ones for para-substituted styrenes (6.5 ppm) and ethylbenzenes (-0.9 ppm), model compounds which were taken to represent extremes of conjugative ability.Similar results were found for 15N chemical shifts of trans-3-aryl-oxaziridines, which had a slope of 2.1 ppm, intermediate to those for benzylimines (20.2 ppm) and benzylamines (-1.3 ppm).The order of conjugative ability, which decreases with increasing electronegativity of the hetero group, could not be explained by hybridization changes based on comparing open chain analoques with the above compounds or by conformational factors.The trend can, however, be interpreted qualitatively by perturbation theory which shows that more electronegative hetero groups decrease the extent of interaction between aryl-? and cyclopropane orbitals as well as cross ring conjugation.
