title: C5'-Alkyl Substitution Effects on Digitoxigenin α-l-Glycoside Cancer Cytotoxicity.
abstract: A highly regio- and stereo-selective asymmetric synthesis of various C5'-alkyl side chains of rhamnosyl- and amicetosyl-digitoxigenin analogs has been established via palladium-catalyzed glycosylation with post-glycosylated dihydroxylation or diimide reduction. The C5'-methyl group in both α-l-rhamnose and α-l-amicetose digitoxin analogs displayed a steric directed apoptosis induction and tumor growth inhibition against non-small cell human lung cancer cells (NCI-H460). The anti-tumor activity is significantly reduced when the steric hindrance is increased at C5'-stereocenter.
authors.affiliation: Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, United States.
authors.forename: Hua-Yu Leo
authors.initials: HY
authors.lastname: Wang
authors.forename: Zhang
authors.initials: Z
authors.lastname: Qi
authors.forename: Bulan
authors.initials: B
authors.lastname: Wu
authors.forename: Sang-Woo
authors.initials: SW
authors.lastname: Kang
authors.forename: Yon
authors.initials: Y
authors.lastname: Rojanasakul
authors.forename: George A
authors.initials: GA
authors.lastname: O'Doherty