Transdithioacetalization of acetals, ketals, oximes, enamines and tosylhydrazones catalysed by natural kaolinitic clay
作者:G. K. Jnaneshwara、N. B. Barhate、A. Sudalai、V. H. Deshpande、R. D. Wakharkar、A. S. Gajare、M. S. Shingare、R. Sukumar
DOI:10.1039/a706475f
日期:——
Natural kaolinitic clay efficiently catalyses the transdithioacetalization of acetals, ketals, oximes, enamines and tosylhydrazones with ethane-1,2-dithiol and propane-1,3-dithiol to produce the corresponding dithiolanes in high yields.
Origin of High Diastereoselectivity in Reactions of Seven‐Membered‐Ring Enolates
作者:Olga Lavinda、Collin H. Witt、K. A. Woerpel
DOI:10.1002/anie.202114183
日期:2022.3.28
The diastereoselectivereactions of chiral seven-membered-ring enolates have been systematically investigated. Diastereoselectivity was found to be general for ϵ-lactams, ϵ-lactones, and cycloheptanones with various substituent patterns. Computational investigations provided insight into the origin of the diastereoselectivity. A model for predicting the stereochemistry of seven-membered-ring enolate
Mousseron et al., Bulletin de la Societe Chimique de France, 1953, p. 974,979
作者:Mousseron et al.
DOI:——
日期:——
Oximes: Metabolic Activation and Structure−Allergenic Activity Relationships
作者:Moa Andresen Bergström、Sofia I Andersson、Kerstin Broo、Kristina Luthman、Ann-Therese Karlberg
DOI:10.1021/jm701092n
日期:2008.4.1
Metabolic activation of chemicals (prohaptens) in the skin can cause allergic contact dermatitis. We have explored structure -allergenic activity relationships for seven potential oxime prohaptens using the local lymph node assay and a GSH trapping screen with liver microsomes. The general structure -allergenic activity relationships found were that an (alpha,beta-unsaturation is necessary for an oxime to be a prohapten and that increased steric hindrance around this double bond leads to reduction in sensitizing capacity. We also found that sensitizing oximes can be distinguished in vitro from nonsensitizers by monitoring of monooxidized (+16 Da) GSH conjugates in the GSH trapping screen. However, care should be taken when interpreting data from GSH trapping screens, as nonsensitizers may also form GSH conjugates via alternative mechanisms. This investigation emphasizes the importance of considering cutaneous bioactivation in toxicity assessment of chemicals used in contact with the skin.
A New, Convenient Method for Semmler-Wolff Aromatization
作者:Yasumitsu Tamura、Yoshihiko Yoshimoto、Kiyoshi Sakai、Yasuyuki Kita