Abstract: A heteroaromatic amide derivative or salt thereof showing high efficacy for diseases associated with Nav1.7 is represented by general formula (I) [wherein, X1-X2 is N—C or C—N, Y1, Y2, Y3 and Y4 are —CH2—, —CR4aH— or —O— and so on, Z1 is —O— and so on, ring A is a 3- to 7-membered monocyclic aromatic ring and so on, R1a and R1b are a hydrogen atom or a halogen atom and so on, R2 is a hydrogen atom and so on, R3a, R3b and R3c are a hydrogen atom or an optionally substituted C1-C6 haloalkyl group and so on, R4a, R4b and R4c are, an optionally substituted C1-C6 haloalkyl group or C1-C6 haloalkoxy group and so on, R5a is a hydrogen atom and so on, R5a and R5b together form —CH2O— and so on, R6a and R6b are a hydrogen atom and so on, n is 1 or 2.].

Abstract: A method for producing (R)-5-(3,4-difluorophenyl)-5-[(3-methyl-2-oxopyridin-1(2H)-yl)methyl]imidazolidine-2,4-dione, the method comprising, (a) a step for isolating an isomer represented by formula (2) from a mixture of isomers represented by formula (1), and (b) a step for obtaining (R)-5-(3,4-difluorophenyl)-5-[(3-methyl-2-oxopyridin-1(2H)-yl)methyl]imidazolidine-2,4-dione by removing the menthyloxycarbonyl group from the compound represented by formula (2), which was isolated in step (a).

Abstract: A method for producing (R)-5-(3,4-difluorophenyl)-5-[(3-methyl-2-oxopyridin-1(2H)-yl)methyl]imidazolidine-2,4-dione, the method comprising, (a) a step for isolating an isomer represented by formula (2) from a mixture of isomers represented by formula (1), and (b) a step for obtaining (R)-5-(3,4-difluorophenyl)-5-[(3-methyl-2-oxopyridin-1(2H)-yl)methyl]imidazolidine-2,4-dione by removing the menthyloxycarbonyl group from the compound represented by formula (2), which was isolated in step (a).

Abstract: General formula (I): The present invention pertains to: a pyridone derivate or a salt thereof represented by general formula (I); or a medicine containing the pyridone derivative or salt thereof as an active ingredient. [In the formula, ring A, R1, R2, R3 and R4 are specific groups.

Abstract: Provided is (+)-5-(3,4-difluorophenyl)-5-[(3-methyl-2-oxopyridin-1(2H)-yl)methyl]imidazolidine-2,4-dione or a salt thereof. Also provided is a drug containing as the active ingredient (+)-5-(3,4-difluorophenyl)-5-[(3-methyl-2-oxopyridin-1(2H)-yl)methyl]imidazolidine-2,4-dione or a salt thereof.

Abstract: General formula (I): The present invention pertains to: a pyridone derivate or a salt thereof represented by general formula (I); or a medicine containing the pyridone derivative or salt thereof as an active ingredient. [In the formula, ring A, R1, R2, R3 and R4 are specific groups.

Abstract: General formula (I): The present invention pertains to: a pyridone derivate or a salt thereof represented by general formula (I); or a medicine containing the pyridone derivative or salt thereof as an active ingredient. [In the formula, ring A, R1, R2, R3 and R4 are specific groups.

Abstract: Provided is (+)-5-(3,4-difluorophenyl)-5-[(3-methyl-2-oxopyridin-1(2H)-yl)methyl]imidazolidine-2,4-dione or a salt thereof. Also provided is a drug containing as the active ingredient (+)-5-(3,4-difluorophenyl)-5-[(3-methyl-2-oxopyridin-1(2H)-yl)methyl]imidazolidine-2,4-dione or a salt thereof.

Abstract: General formula (I): The present invention pertains to: a pyridone derivate or a salt thereof represented by general formula (I); or a medicine containing the pyridone derivative or salt thereof as an active ingredient. [In the formula, ring A, R1, R2, R3 and R4 are specific groups.