A novel xanthine compound having bronchodilating and brain function improving activity represented by the following formula (I) and (II):

wherein R¹ represents a hydrogen atom, 4-methoxybenzyl group, a straight- or branched-chain alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 6 carbon atoms; R² represents a hydrogen atom, a straight- or branched-chain alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 6 carbon atoms; n represents an integer of from 1 to 4; and A represents -COCH₃ or - C(OR³)(OR⁴)CH₃ in which R³ and R⁴ independently represents an alkyl group having 1 to 3 carbon atoms or R³ together with R⁴ represents a polymethylene group having 2 to 4 carbon atoms is disclosed. Also disclosed are a pharmacologically acceptable salt of the same, method for preparing the same, and a pharmaceutical composition for the treatment of respiratory tract disease or brain disfunction comprising the effective amount of same.