To provide a new compound that is useful in the treatment of central nervous system disorder.

This compound is represented by formula I (n, m are each 1, 2; p is 1-6; q is 0, 1-3; R1 and R2 are each H or the like; R3 to R5 are each H or the like; R6 is a 1-4C alkyl; dotted line means a double bond; F bonds to the 6 or 7 position), its salt or ester, typically a compound of formula II. This new compound is obtained by reaction of a compound of formula III with an aldehyde equivalent of formula IV (X is a halogen). The aldehyde is prepared by oxidizing a suitable terminal alkene with ozone or the like followed by reductive amination of the aldehyde group with sodium cyanoborohydride or using triacetoxycyanoborohydride and a compound of formula III, preferably in a polar solvent as acetonitrile in the presence of a base as sodium iodide at 50-150°C. The new compound of formula I has an effective action of activating the central nervous system. The daily dose for treating an adult person is 0.5-100 mg.