A 2,4,6-substituted phenol having the formula
wherein X is S or CH₂; R¹ and R² are the same or different from each other and each is a lower alkyl group; R³ is a group of the formula:
in which R⁴ is hydrogen atom or a lower alkyl group; R⁵ and R⁶ are the same or different from each other and each is hydrogen atom, a lower alkyl group, or a phenyl group which may be substituted,
or a pharmaceutically acceptable salt thereof; a pharmaceutical composition comprising a therapeutically effective amount of a compound having the formula (I), as an effective ingredient, in association with a pharmaceutically acceptable substantially nontoxic carrier or excipient and a pharmaceutical composition for use in the treatment of lipemia of mammals comprising a therapeutically effective amount of at least one compound having the formula (I). According to the present invention there can be provided useful antiatherosclerotic agents and antilipenic agents.