Benzimidazole derivative, hair growth promoter and external composition for skin using the same

A benzimidazole compound or a salt thereof expressed by the following Formula (I):

• wherein m=0;
• A is —(CH2)n—NR2R3, and B is an alkyl group having at least 10 carbon atoms;
• n is an integer of 0-5;
• R2 and R3 individually represent a hydrogen atom, a lower alkyl group, a phenyl group or a benzyl group, or —NR2R3 may be a heterocycle having 3-7 members;
• and R4 is selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, a trifluoromethyl group, a lower alkyl group, a lower acyl group, a carboxyl group, a lower alkoxycarbonyl group, a carbamoyl group, a lower alkylcarbamoyl group, an amino group, a lower alkylamino group, a lower acylamino group, a hydroxy group, a lower alkoxy group and a lower acyloxy group.

A benzimidazole compound or a salt thereof expressed by the following Formula (I):

• wherein A is R1 and B is —(CH2)n—NR2R3;
• R1 is a hydrocarbon group of having 10 to 30 carbon atoms;
• R2 and R3 individually represent a hydrogen atom, a lower alkyl group, a phenyl group or a benzyl group, or —NR2R3 may be a heterocycle having 3-7 members;
• R4 is selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, a trifluoromethyl group, a lower alkyl group, a lower acyl group, a carboxyl group, a lower alkoxycarbonyl group, a carbamoyl group, a lower alkylcarbamoyl group, an amino group, a lower alkylamino group, a lower acylamino group, a hydroxy group, a lower alkoxy group and a lower acyloxy group;
• R5 is a hydrogen atom, a lower alkyl group, a lower acyl group or a lower alkylcarbamoyl group;
• m is 1;
• n is an integer of 0-5;
• and
• wherein —(CONR5)m—B may be expressed by the following Group (W):
• wherein R2 is a hydrogen atom, a lower alkyl group, a phenyl group or a benzyl group and ring E is a heterocycle of 6 or 7 members.

A method for promoting hair growth, which comprises applying an effective amount of the benzimidazole compound or the pharmacologically acceptable salt thereof expressed by the following Formula (I):

• wherein each of A and B is R1 or —(CH2)n—NR2R3, wherein when A is R1, B is —(CH2)n—NR2R3 and when A is —(CH2)n—NR2R3, B is R1;
• R1 is a hydrocarbon group having 10 to 30 carbon atoms;
• R2 and R3 individually represent a hydrogen atom, a lower alkyl group, a phenyl croup or a benzyl group, or —NR2R3 may be a heterocycle having 3-7 members;
• wherein when B is —(CH2)n—NR2R3 and m=1, —(CONR5)m—B may be the following Group (W):
• wherein R2 is a hydrogen atom, a lower alkyl group, a phenyl group or a benzyl group and ring E is a heterocycle of 6 or 7 members;
• R4 is selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, a trifluoromethyl group, a lower alkyl group, a lower acyl group, a carboxyl group, a lower alkoxycarbonyl group, a carbamoyl group, a lower alkylcarbamoyl ground an amino group, a lower alkylamino group, a lower acylamino group, a hydroxy group, a lower alkoxy group and a lower acyloxy group;
• R5 is a hydrogen atom, a lower alkyl group, a lower acyl group or a lower alkylcarbamoyl group;
• wherein when B is —(CH2)n—NR2R3 and m=1, —(CONR5)m—B may be Group (W);
• m is 0 or 1;
• n is an integer of 0-5;
• and
• wherein when m is 0 then A is —(CH2)n—NR2R3 and B is an alkyl group having at least 10 carbon atoms in admixture with one or more of cosmetically or pharmaceutically acceptable additives, carriers, excipients or diluents therefor on the skin of a mammalian subject in need of such treatment.