To obtain the subject compound useful as a medicine acting in the stage of a dopaminergic system in Parkinson's disease, disorder of memory and mental disease.

This amino compound is shown by formula I ((n) is 0 or 1: Y is H, etc.) in a racemic state or in an optical isomer state, such as (7R,S)-7-(N, N-dipropyl amino)-6,7,8,9-tetrahydrocyclopenta[a]naphthalen-1-one. The compound is obtained by reacting a tertiary amine of formula II (X is Br or I) with butyllithium and dimethylformamide in tetrahydrofuran to give an aldehyde of formula III, treating the aldehyde malonic acid in the presence of piperidine in pyridine to give a compound of formula IV, hydrogenating the compound to give an acid of formula V, subjecting the acid to ring formation using hot polyphosphate to form a compound of formula VI and treating the compound with a specific halogenated compound. The dose of the compound is in the range of 0.5-25 mg of the active ingredient for once to three times daily.