An ameliorating agent for cancer chemotherapy is disclosed, which
comprises a chromanol glycoside represented by the following general
formula (1) ##STR00001## (wherein R.sup.1, R.sup.2, R.sup.3, and
R.sup.4, which are identical or different from each other, stand for a
hydrogen atom or a lower alkyl group, R.sup.5 stands for a hydrogen atom,
a lower alkyl group, or a lower acyl group, X stands for a monosaccharide
residue or an oligosaccharide residue optionally having the hydrogen atom
of the hydroxyl group in the saccharide residue substituted with a lower
alkyl group or a lower acyl group, n is an integer in the range of 0-6,
and m is an integer in the range of 1-6).According to this invention, a
novel ameliorating agent for cancer chemotherapy is provided which acts
safely and effectively in a small dosage to enhance the carcinostatic
action of an anti-cancer agent in cancer chemotherapy and repressing side
effects by cancer chemotherapy as well.