Abstract: The following compound is provided as an agent for treating a disease induced by production, secretion and/or deposition of amyloid ? protein, for example, a compound represented by the formula (I): wherein ring A in an optionally substituted carbocyclic group or an optionally substituted heterocyclic group, R1 is optionally substituted lower alkyl or the like, R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or the like, R3a and R3c are each independently hydrogen, halogen, hydroxy, optionally substituted lower alkyl or the like, or a pharmaceutical acceptable salt thereof, or a solvate thereof.

Abstract: The following compound is provided as an agent for treating a disease induced by production, secretion and/or deposition of amyloid ? protein, for example., a compound represented by the formula (I): wherein ring A in an optionally substituted carbocyclic group or an optionally substituted heterocyclic group. R1 is optionally substituted lower alkyl or the like, R2a and R2b each independently hydrogen, optionally substituted lower alkyl or the like, R3a and R3c are each independently hydrogen, halogen, hydroxy, optionally substituted lower alkyl or the like, or a pharmaceutical acceptable salt thereof, or a solvate thereof.

Abstract: The following compound is provided as an agent for treating a disease induced by production, secretion and/or deposition of amyloid ? protein, for example, a compound represented by the formula (I): wherein ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group, R1 is optionally substituted lower alkyl or the like, R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or the like, R3a and R3c are each independently hydrogen, halogen, hydroxy, optionally substituted lower alkyl or the like, or a pharmaceutically acceptable salt thereof, or a solvate thereof.

Abstract: The following compound is provided as an agent for treating a disease induced by production, secretion and/or deposition of amyloid ? protein, for example, a compound represented by the formula: wherein Ry is halogeno lower alkyl; ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group, R1 is optionally substituted lower alkyl or the like, R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or the like, R3a, R3b, R3c and R3d are each independently hydrogen, halogen, hydroxy, optionally substituted lower alkyl or the like, or a pharmaceutically acceptable salt thereof, or a solvate thereof.

Abstract: The following compound is provided as an agent for treating a disease induced by production, secretion and/or deposition of amyloid ? protein, for example, a compound represented by the formula (I): wherein ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group, R1 is optionally substituted lower alkyl or the like, R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or the like, R3a and R3c are each independently hydrogen, halogen, hydroxy, optionally substituted lower alkyl or the like, or a pharmaceutically acceptable salt thereof, or a solvate thereof.

Abstract: This invention provides a compound of the formula (I): wherein the ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group; R1 is optionally substituted lower alkyl, optionally substituted lower alkenyl, optionally substituted lower alkynyl; R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or optionally substituted acyl; R3a, R3b, R3c and R3d are each independently hydrogen, halogen, hydroxy or optionally substituted lower alkyl etc.; a pharmaceutically acceptable salt or solvate thereof, which is useful for treating diseases induced by production, secretion and/or deposition of amyloid ? protein.

Abstract: This invention provides a compound of the formula (I): wherein the ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group; R1 is optionally substituted lower alkyl, optionally substituted lower alkenyl, optionally substituted lower alkynyl; R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or optionally substituted acyl; R3a, R3b, R3c and R3d are each independently hydrogen, halogen, hydroxy or optionally substituted lower alkyl etc.; a pharmaceutically acceptable salt or solvate thereof, which is useful for treating diseases induced by production, secretion and/or deposition of amyloid ? protein.

Abstract: This invention provides a compound of the formula (I): wherein the ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group; R1 is optionally substituted lower alkyl, optionally substituted lower alkenyl, optionally substituted lower alkynyl; R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or optionally substituted acyl; R3a, R3b, R3c and R3d are each independently hydrogen, halogen, hydroxy or optionally substituted lower alkyl etc.; a pharmaceutically acceptable salt or solvate thereof, which is useful for treating diseases induced by production, secretion and/or deposition of amyloid ? protein.

Abstract: This invention provides a compound of the formula (I): wherein the ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group; R1 is optionally substituted lower alkyl, optionally substituted lower alkenyl, optionally substituted lower alkynyl; R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or optionally substituted acyl; R3a, R3b, R3c and R3d are each independently hydrogen, halogen, hydroxy or optionally substituted lower alkyl etc.; a pharmaceutically acceptable salt or solvate thereof, which is useful for treating diseases induced by production, secretion and/or deposition of amyloid ? protein.

Abstract: This invention provides a compound of the formula (I): wherein the ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group; R1 is optionally substituted lower alkyl, optionally substituted lower alkenyl, optionally substituted lower alkynyl; R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or optionally substituted acyl; R3a, R3b, R3c and R3d are each independently hydrogen, halogen, hydroxy or optionally substituted lower alkyl etc.; a pharmaceutically acceptable salt or solvate thereof, which is useful for treating diseases induced by production, secretion and/or deposition of amyloid ? protein.

Abstract: This invention provides a compound of the formula (I): wherein the ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group; R1 is optionally substituted lower alkyl, optionally substituted lower alkenyl, optionally substituted lower alkynyl; R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or optionally substituted acyl; R3a, R3b, R3c and R3d are each independently hydrogen, halogen, hydroxy or optionally substituted lower alkyl etc.; a pharmaceutically acceptable salt or solvate thereof, which is useful for treating diseases induced by production, secretion and/or deposition of amyloid ? protein.

Abstract: The present invention provides, for example, a compound of the following formula (I): wherein R1 is substituted amino and the like, R2 is halogen and the like, R3 is substituted or unsubstituted lower alkyl and the like, RA and RB are each independently hydrogen, substituted or unsubstituted lower alkyl and the like, RC and RD are each independently hydrogen, substituted or unsubstituted lower alkyl, or RC and RD together with the carbon atom to which they are attached may form a substituted or unsubstituted carbocycle, and ring A is a carbocycle or a heterocycle, its pharmaceutically acceptable salt, or a solvate thereof as a therapeutic agent for diseases induced by production, secretion and/or deposition of amyloid-?proteins.

Abstract: The following compound is provided as an agent for treating a disease induced by production, secretion and/or deposition of amyloid ? protein, for example, a compound represented by the formula (I): wherein ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group, R1 is optionally substituted lower alkyl or the like, R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or the like, R3a and R3c are each independently hydrogen, halogen, hydroxy, optionally substituted lower alkyl or the like, or a pharmaceutically acceptable salt thereof, or a solvate thereof.

Abstract: This invention provides a compound of the formula (I): wherein the ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group; R1 is optionally substituted lower alkyl, optionally substituted lower alkenyl, optionally substituted lower alkynyl; R2a and R2b are each independently hydrogen, optionally substituted lower alkyl or optionally substituted acyl; R3 a, R3 b, R3 c and R3 d are each independently hydrogen, halogen, hydroxy or optionally substituted lower alkyl etc.; a pharmaceutically acceptable salt or solvate thereof, which is useful for treating diseases induced by production, secretion and/or deposition of amyloid ? protein.