Seong-Cheol Bang, Hyun-Hee Seo, Hye-Rim Shin
May 15, 2008
Citations
1
Influential Citations
8
Citations
Quality indicators
Journal
Archives of Pharmacal Research
Abstract
The sugar structures of triterpenoid saponins, such as α-hederin, are intimately associated with their antitumor activities and other biological activities. The α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside group of α-hederin alters the cytotoxicity of its aglycon, hederagenin. This study explored the role of this saccharide unit in the cytotoxic effect of α-hederin and the possibility of its use as a carrier moiety in prodrugs of anticancer agents. A new convenient and practical procedure for the preparation of 4-methoxybenzoyl-2,3,4-tri-O-benzoyl-α-l-rhamnopyranosyl-(1→2)-3,4-O-dibenzoyl-β-l-arabinopyranoside (2) from 4-methoxybenzoyl-β-l-arabinopyranoside was accomplished using four steps with an overall yield of 63%. The use of BF3-OEt2 as a catalyst in the glycosylation step in this procedure had a large advantage over the TMSOTf catalyst used in the usual method. Moreover, the key intermediate obtained in this procedure, 4-methoxybenzoyl-2,3,4-tri-O-benzoyl-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside (7), was selectively transformed to 4-methoxybenzoyl-2,3,4-tri-O-benzoyl-α-l-rhamnopyranosyl-(1→2)-4-O-acetyl-α-l-arabinopyranoside (9) and 4-methoxybenzoyl-2,3,4-tri-O-benzoyl-α-l-rhamnopyranosyl-(1→2)-3-O-benzoyl-β-l-arabinopyranoside (10). These derivatives did not show any cytotoxicity against human cancer cell lines. Thus the 3-O-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside could be used as a nontoxic carrier moiety to enhance the activity of anticancer drugs.