Abstract: [Problem] To provide a compound useful as medicine having PDE4B inhibitory activity, in particular, as an active ingredient of a composition for treating or preventing schizophrenia, Alzheimer's disease, dementia, depression and the like. [Measures for Solution] The present inventors examined compounds having PDE4B inhibitory activity and found that a tricyclic or tetracyclic imidazo[1,2-a]pyridine derivative or salts thereof had a superior PDE4B inhibitory activity, thereby completing the present invention. The imidazo[1,2-a]pyridine derivative can be used as an agent for treating or preventing schizophrenia, Alzheimer's disease, dementia, depression and the like.

Abstract: Anytime obtained is uniform crystal of N-(4-fluorophenyl)-N?-phenyl-N?-(pyrimidin-2-ylmethyl)-1,3,5-triazine-2,4,6-triamine (compound A) and/or N,N?-bis (4-fluorophenyl)-N?-(pyrimidin-2-ylmethyl)-1,3,5-triazine-2,4,6-triamine (compound B) as a medicament or a starting material for the preparation of the medicament, and provided are a fumarate of the compound A and/or the compound B having excellent stability and a novel crystal thereof. A salt of the compound A and/or the compound B with fumaric acid enables uniform crystal to be anytime obtained, and thus, it is a compound that is very useful as a medicament or a starting material for the preparation of the medicament having excellent stability.

Abstract: Provided is a compound that is an NMDA receptor antagonist having a broader safety margin, and is useful as an agent for treating or preventing Alzheimer's disease, cerebrovascular dementia, Parkinson's disease, ischemic apoplexy, or pain. A novel compound or a salt thereof, which is characterized in that it has an amino group and R1 (lower alkyl, cycloalkyl, -lower alkylene-aryl, aryl which may be substituted, and the like) on carbon atoms of indane, cyclopenta[b]thiophene, cyclopenta[b]furan, cyclopenta[b]pyridine, or cyclopenta[c]pyridine ring, or 2,3 -dihydro-1-benzofuran, 2,3-dihydro-1-benzothiophene, indoline ring, or the like, and has R2 and R3 (the same or different, each lower alkyl or aryl) on carbon atoms beside them, and an NMDA receptor antagonist comprising the same as an active component.

Abstract: Anytime obtained is uniform crystal of N-(4-fluorophenyl)-N?-phenyl-N?-(pyrimidin-2-ylmethyl)-1,3,5-triazine-2,4,6-triamine (compound A) and/or N,N?-bis (4-fluorophenyl)-N?-(pyrimidin-2-ylmethyl)-1,3,5-triazine-2,4,6-triamine (compound B) as a medicament or a starting material for the preparation of the medicament, and provided are a fumarate of the compound A and/or the compound B having excellent stability and a novel crystal thereof. A salt of the compound A and/or the compound B with fumaric acid enables uniform crystal to be anytime obtained, and thus, it is a compound that is very useful as a medicament or a starting material for the preparation of the medicament having excellent stability.

Abstract: Provided is a compound that is an NMDA receptor antagonist having a broader safety margin, and is useful as an agent for treating or preventing Alzheimer's disease, cerebrovascular dementia, Parkinson's disease, ischemic apoplexy, or pain. A novel compound or a salt thereof, which is characterized in that it has an amino group and R1 (lower alkyl, cycloalkyl, -lower alkylene-aryl, aryl which may be substituted, and the like) on carbon atoms of indane, cyclopenta[b]thiophene, cyclopenta[b]furan, cyclopenta[b]pyridine, or cyclopenta[c]pyridine ring, or 2,3-dihydrdo-1-benzofuran, 2,3-dihydrdo-1-benzothiophene, indoline ring, or the like, and has R2 and R3 (the same or different, each lower alkyl or aryl) on carbon atoms beside them, and an NMDA receptor antagonist comprising the same as an active component.

Abstract: Provided are compounds which are an NMDA antagonist having a broad safety margin and are useful as a treating agent or a preventing agent for Alzheimer's disease, cerebrovascular dementia, Parkinson's disease, ischemic apoplexy, pain, etc. Concretely provided are an amine derivative or its salt characterized in that the amine-containing structure A therein bonds to a 2- or 3-cyclic condensed ring (e.g., indane, tetralone, 4,5,6,7-tetrahydrobenzothiophene, 4,5,6,7-tetrahydrobenzofuran, 7,8-dihydro-6H-indeno[4,5-b]furan, 2,3-dihydro-1H-cyclopenta[1]naphthalene) via X1 (bond or lower alkylene); and an NMDA antagonist containing it as an active ingredient thereof.

Abstract: Imidazole-substituted quinoxalinedione derivatives represented by the following general formula (I) or pharmaceutically acceptable salts thereof and pharmaceutical compositions useful as glutamate receptor antagonists and the like, which comprise said compounds or salts thereof and pharmaceutically acceptable carriers. ##STR1## (Each symbol in the formula has the following meaning: A: a group represented by a formula (CH.sub.2).sub.m or a group represented by a formula Ph--(CH.sub.2).sub.p (Ph: a phenyl group),X: an oxygen atom or a group represented by a formula NR.sup.4,R.sup.1 : a hydrogen atom, a hydroxyl group or a triazolyl group, with the proviso that X may be a bond when R.sup.1 is a triazolyl group,R.sup.2 : a hydrogen atom, a nitro group, a halogeno-lower alkyl group, a cyano group, an amino group, a mono- or di-lower alkylamino group or a halogen atom,R.sup.3 and R.sup.

Abstract: Thiophene derivatives represented by the following general formula (I) or pharmaceutically acceptable salts thereof. Said compounds act as an anti-PCP agonist and therefore are useful as psychotropic or antischizophrenic agents and so on. ##STR1## (In the above formula, R.sub.1 is a formula --A.sub.1 --X.sub.1 --R.sub.3 ; R.sub.2 is a formula --A.sub.2 --X.sub.2 --R.sub.4 or does not exist; B ring is a 7- to 10-membered nitrogen-containing cycloalkyl ring; Ar ring is an aryl or heteroaryl ring; A.sub.1, A.sub.2 and A.sub.3 may be the same or different from one another and each represents a bond or a lower alkylene group; X.sub.1 and X.sub.2 may be the same or different from each other and each represents a bond or a formula --O--, --S--or the like; R.sub.3 and R.sub.

Abstract: N-(3-Pyrrodinyl)benzamide derivatives represented by the following general formula (I) which have potent and selective antagonism against dopamine D.sub.3 and/or D.sub.4 receptor and are useful as a psychotropic, a schizophrenia-treating agent and the like, or a pharmaceutically acceptable salt thereof or a pharmaceutical preparation thereof.

Abstract: A process is provided for preparing a tetrahydrobenzimidazole derivative represented by Formula (Ib): ##STR1## wherein Het representa s heterocyclic group which may be substituted with 1 to 3 substituents selected from the group consisting of a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a cycloalkyl-lower alkyl group, an aralkyl group, a lower alkoxycarbonyl group, and a halogen atom; and X.sup.2 represents a single bond connected to the carbon atom of the heterocyclic ring as represented by Het. The process comprises reacting a heterocyclic compound represented by Formula (IIIa):Het--X.sup.2 --H (IIIa)wherein Het and X.sup.2 are as defined above, with a carboxylic acid represented by Formula (II): ##STR2## or a reactive derivative thereof.

Abstract: A tetrahydrobenzimidazole derivative represented by formula (I): ##STR1## wherein Het represents a heterocyclic group which may be substituted with 1 to 3 substituents selected from the group consisting of a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a cycloalkyl-lower alkyl group, an aralkyl group, a lower alkoxy group, a nitro group, a hydroxyl group, a lower alkoxycarbonyl group, and a halogen atom; and X represents a single bond or --NH-- which is bonded to the carbon atom or nitrogen atom of the heterocyclic ring, or a pharmaceutically acceptable salt thereof.The compound of formula (I) and a salt thereof exhibits antagonism against 5-HT.sub.3 receptor.

Abstract: The present invention is a pyrazine derivative which has glutamate receptor antagonizing activity, represented by formula: ##STR1## wherein Z represents C or N, provided that two Zs are not N atoms at the same time; R.sup.1 represents: ##STR2## wherein ##STR3## represents ##STR4## R.sup.6 represents H or alkyl, and R.sup.7 and R.sup.8 represent each H, alkyl, nitro or phenyl, or alternatively R.sup.7 and R.sup.8 are combined together to represent butadienylene or 1,4-butylene; R.sup.2 and R.sup.3 represent each H, F, cyano, acyl, nitro, alkyl, morpholino or one of said species of R.sup.1 ; R.sup.4 and R.sup.5 represent each H, hydroxyl, alkyl, cycloalkyl, heterocycle, phenyl, or Y-substituted alkyl; Y represents hydroxyl, acyloxy, F-substituted methyl, cycloalkyl, tetrahydrofuryl, carboxyl, alkoxycarbonyl or ##STR5## R.sup.9 and R.sup.10 represent each H or alkyl, or alternatively R.sup.9 and R.sup.10 are combined together to represent a 5- or 6-membered cyclic group which may contain oxygen atom(s).