Xanthine derivatives for the treatment of dementia.

摘要

A novel xanthine derivative of the formula (I): <CHEM> wherein one of R<1> and R<2> represents substituted or unsubstituted lower alkyl, lower alkenyl, lower alkynyl, substituted or unsubstituted alicyclic alkyl, substituted or unsubstituted phenyl, or substituted or unsubstituted benzyl; and the other represents -(CH<6>)m-X wherein m is 2 or 3, and X is <CHEM> where a is NH, O or S, and b and d are the same or different and are CH or N or <CHEM> where e, g and h are the same or different and are CH or N; Q represents <CHEM> (wherein R<3> and R4 are the same or different and are substituted or unsubstituted alicyclic alkyl), <CHEM> (wherein Y is a single bond or alkylene, n is 0 or 1), <CHEM> (wherein ---- is a single or double bond. Y is the same as defined above), or <CHEM> (wherein Y is the same as defined above); or a pharmacologically accetable salt thereof is disclosed. This derivative has anti-dementia activity.