Autor: Kvasnica, M.; Sarek, J.; Vlk, M.; Budesinsky, M.; Stepanek, O.; Kubelka, T.; Plutnarova, I.;
Název práce v češtině: Studium stereoselectivity redukce 18-oxo des-E triterpenoidů borohydridem sodným v přítomnosti chloridu ceritého
Název práce v angličtině: Study of stereoselectivity of reduction of 18-oxo des-E triterpenoids by sodium borohydride in the presence of cerium chloride
Studentská publikace: ne

Klíčová slova v angličtině: reduction, stereoselectivity, ketone

Abstrakt anglicky: Herein, we studied the stereoselectivity of the reduction of the 18-oxo group in cytotoxically active des-Elupane derivatives with respect to a dependence on the substituent type at the 17-position by means ofsodium borohydride and also in the presence of cerium chloride. It was found that the stereoselectivity ofthe reduction of the 18-keto group both depended on the type and length of the substituent chain at the17-position. In most cases, 18a-hydroxyderivatives were obtained by the assumed attack from the upperside. However, in the case of 18-oxo-17a, 17b-disubstituted derivatives and a 17-methylene derivative, amixture of both epimeric 18a and 18b alcohols was obtained by the reduction with borohydride itself.However, if the reduction of the 18-oxo-17a, 17b-disubstituted derivatives was carried out in the presenceof cerium chloride, the corresponding 18a-hydroxyalcohols were obtained exclusively; conversely,if the 17-methylene derivative was reduced, the 18b-epimer prevails.““
Jazyk v originále: angličtina
Název časopisu: Tetrahedron Asymmetry
Rok: 2011
Svazek (ročník): 22
Číslo časopisu v rámci uvedeného svazku: 9
Strana od-do: 1011-1020

Q1: ne

Způsob financování: GACR 305/09/1216, KAN 200200651, MSM 6198959216