Abstract: The present invention provides a diamine derivative or the like represented by the general formula (I): {wherein Q represents an oxygen atom or the like, RG represents a hydrogen atom or the like, RI represents (wherein p and r may be the same or different, and each represents 0 or the like, RA represents a hydrogen atom or the like, and RB and RC may be the same or different, and each represents a hydrogen atom or the like), RH represents a hydrogen atom or the like, and RJ represents: (wherein q and s may be the same or different, and each represents 0 or the like, RD represents a hydrogen atom or the like, and RE and RF may be the same or different, and each represents a hydrogen atom or the like) or the like}, etc.

Abstract: For example, a piperidine derivative represented by following formula (I) (wherein, —C(?O)-Z- represents —C(?O)—CH2—, —C(?O)—C(CH3)2—, —C(?O)—NH—, —C(?O)—O—, —C(?O)—S—, —C(?O)—CH2CH2—, —C(?O)—CH?CH—, —C(?O)—CH2O—, —C(?O)—CH2S—, —C(?O)—CH2CH2CH2— or —C(?O)—NR8CH2—; R1 represents a hydrogen atom, substituted or unsubstituted lower alkyl, or the like; R2 represents a hydrogen atom or hydroxy; R3 represents a hydrogen atom, substituted or unsubstituted lower alkyl, or the like; R5 represents a hydrogen atom, hydroxy, or the like; R6 represents a hydrogen atom, hydroxy, substituted or unsubstituted lower alkyl, or the like, etc.

Abstract: (wherein R1, R2 and R3 are the same or different, and represent a hydrogen atom, lower alkyl, lower alkenyl or lower alkynyl; R4 represents cycloalkyl, —(CH2)n—R5 or a group represented by the above formula (II); and X1 and X2 are the same or different, and represent an oxygen atom or a sulfur atom) The present invention provides, for example, agents for preventing and/or treating higher brain dysfunction comprising, as an active ingredient, a xanthine derivative represented by the above formula (I) or a pharmaceutically acceptable salt thereof.

Abstract: [wherein n represents an integer of from 1 to 4, R1 represents substituted or unsubstituted lower alkyl, —C(?Y)R9 or the like, R2 represents a hydrogen atom, substituted or unsubstituted lower alkyl or the like, R3 represents substituted or unsubstituted lower alkyl, substituted or unsubstituted aryl, a substituted or unsubstituted heterocyclic group or the like, and R4 represents halogen or the like.]A phosphodiesterase 10A inhibitor which comprises a quinoline derivative represented by the above formula (I) or a pharmaceutically acceptable salt thereof as an active ingredient is provided.

Abstract: The present invention provides an &agr;2c-adrenoceptor antagonist comprising, as an active ingredient, a condensed-ring-pyrimidine derivative represented by general formula (I) below or a pharmaceutically acceptable salt thereof useful for treating and/or preventing various diseases induced by hyperactivity of &agr;2c-adrenoceptor (for example, Parkinson's disease, L-DOPA-induced dyskinesia, tardive dyskinesia and depression) and the like.

Abstract: A compound of formula (I): ##STR1## wherein R.sub.1 represents hydrogen, hydroxy or acetoxy and R.sub.2 represents hydroxy or acetoxy.The compounds are capable of protecting the nerve cells and also antagonistic activity against N-methyl-D-aspartic acid receptors.They may be prepared by fermentation of a microorganism of the genus Verticillium or a mutant thereof.