3,8-diaminotetrahydroquinoline derivative

A 3,8-diaminotetrahydroquinoline derivative represented by formula (1a):

• wherein X represents CH2, C═O, CH—OR, CH—SR, or CH—NRR′;
• m is a number of 1 or 2;
• Ar represents a phenyl group, a naphthyl group, a 5-membered or 6-membered aromatic heterocyclic group having one or two elements selected from S, N, and O, or a condensed aromatic heterocyclic group formed between a benzene ring and a 5-membered or 6-membered heterocyclic ring having one or two elements selected from S, N, and O, wherein the phenyl, naphthyl, or aromatic heterocyclic groups may be substituted by 1 to 3 halogen atoms, a C1 to C6 alkyl group, or a C1 to C6 alkoxy group;
• R1 and R2, which may be identical to or different from each other, each represent a hydrogen atom or a methyl group;
• R3 represents a C1 to C6 alkyl group, the alkyl group optionally being substituted by a methylthio or benzyloxy group, a phenyl group, a phenyl-C1-4 alkyl group, or an indolyl-C1-4 alkyl group, the phenyl group or the indolyl group optionally being substituted by a C1 to C6 alkyl group, a halogen atom, a hydroxyl group, or a C1 to C6 alkoxy group;
• n is a number of 0 or 1;
• R4 and R5, which may be identical to or different from each other, each represent a hydrogen atom, or a C1 to C6 linear, branched, or cyclic alkyl group, the alkyl group optionally being substituted by a halogen atom, a hydroxyl group, a C1 to C6 alkoxy group, a phenyl group, a benzyloxy group, or a hydroxyphenyl group, or R4 or R5, and R6 or R7 may be linked to the adjacent nitrogen atom to form a pyrrolidine ring or a piperidine ring, the pyrrolidine ring or the piperidine ring optionally being substituted by a hydroxyl group;
• R6 and R7, which may be identical to or different from each other, each represent a hydrogen atom or a C1 to C6 alkyl group;
• and
• R and R′, which may be identical to or different from each other, each represent a hydrogen atom or a C1 to C6 linear, branched, or cyclic alkyl group, or a salt thereof.