Abstract: The present invention provides a compound of the formula: wherein ring A is an optionally substituted 5 to 10-membered aromatic ring; R1 and R2 are the same or different and each is an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group; X is a bond and the like; and L is a divalent hydrocarbon group, and a salt thereof, except 3-(aminomethyl)-2,6,7-trimethyl-4-phenyl-1(2H)-isoquinolinone, 3-(aminomethyl)-2-methyl-4-phenyl-1(2H)-isoquinolinone, 3-(aminomethyl)-6-chloro-2-methyl-4-phenyl-1(2H)-isoquinolinone and 3-(aminomethyl)-2-isopropyl-4-phenyl-1(2H)-isoquinolinone. The compound shows a superior peptidase-inhibitory activity and is useful as an agent for the prophylaxis or treatment of diabetes and the like.

Abstract: The present invention provides a compound of the formula: wherein ring A is an optionally substituted 5 to 10-membered aromatic ring; R1 and R2 are the same or different and each is an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group; X is a bond and the like; and L is a divalent hydrocarbon group, and a salt thereof, except 3-(aminomethyl)-2,6,7-trimethyl-4-phenyl-1(2H)-isoquinolinone, 3-(aminomethyl)-2-methyl-4-phenyl-1(2H)-isoquinolinone, 3-(aminomethyl)-6-chloro-2-methyl-4-phenyl-1(2H)-isoquinolinone and 3-(aminomethyl)-2-isopropyl-4-phenyl-1(2H)-isoquinolinone. The compound shows a superior peptidase-inhibitory activity and is useful as an agent for the prophylaxis or treatment of diabetes and the like.

Abstract: The present invention provides, as an industrially advantageous production method, a method of producing a compound represented by the formula (III)

Abstract: A compound of the formula (I): wherein R is hydrogen or C2-6 alkanoyl; X is halogen; and ring A is benzene ring which is optionally substituted by 1 to 4 substituents selected from {circle around (1)} halogen, {circle around (2)} hydroxy, {circle around (3)} C1-6 alkoxy optionally substituted by halogen or phenyl, {circle around (4)} C1-6 alkylthio optionally substituted by halogen or phenyl, {circle around (5)} C1-6 alkyl optionally substituted by halogen, {circle around (6)} C2-6 alkanoylamino or {circle around (7)} carboxy optionally esterified by C1-6 alkyl, or a salt thereof; which can be used for preventing or treating inflammatory disease, arthritis, chronic rheumatoid arthritis, autoimmune diseases, or rejection after organ transplantation.