The sugar structures of triterpenoid saponins, such as $alpha$-hederin, are intimately associated with their antitumor activities and other biological activities. The $alpha$-L-rhamnopyranosyl-($1{ ightarrow}2$)-$alpha$-L-arabinopyranoside group of $alpha$-hederin alters the cytotoxicity of its aglycon, hederagenin. This study explored the role of this saccharide unit in the cytotoxic effect of $alpha$-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-$alpha$-L-rhamnopyranosyl-($1{ ightarrow}2$)-3,4-O-dibenzoyl-$eta$-L-arabinopyranoside (2) from 4-methoxybenzoyl-$eta$-Larabinopyranoside was accomplished using four steps with an overall yield of 63%. The use of $BF_3-OEt_2$ 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-$alpha$-L-rhamnopyranosyl-($1{ ightarrow}2$)-$alpha$-L-arabinopyranoside (7), was selectively transformed to 4-methoxybenzoyl-2,3,4-tri-O-benzoyl-$alpha$-L-rhamnopyranosyl-($1{ ightarrow}2$)-4-O-acetyl-$alpha$-L-arabinopyranoside (9) and 4-methoxybenzoyl-2,3,4-tri-Obenzoyl-$alpha$-L-rhamnopyranosyl-($1{ ightarrow}2$)-3-O-benzoyl-$eta$-L-arabinopyranoside (10). These derivatives did not show any cytotoxicity against human cancer cell lines. Thus the 3-O-$alpha$-L-rhamnopyranosyl-($1{ ightarrow}2$)-$alpha$-L-arabinopyranoside could be used as a nontoxic carrier moiety to enhance the activity of anticancer drugs.