Amino alcohol derivatives

A compound of formula (I) or a pharmacologically acceptable salt, ester or other derivative thereof:

• wherein:
• R1 and R2 are the same or different and each represents a hydrogen atom or an amino protecting group;
• R3 represents a hydrogen atom or a hydroxy protecting group;
• R4 represents a lower alkyl group;
• n represents an integer from 1 to 6;
• X represents an ethylene group, a vinylene group, an ethynylene group, a group of formula —D—CH2— (wherein D represents a carbonyl group, a group of formula —CH(OH)—, an oxygen atom, a sulfur atom, or a nitrogen atom), an aryl group, or an aryl group substituted with 1 to 3 substituents selected from substituent group a;
• Y represent a single bond, a C1-C10 alkylene group, a C1-C10 alkylene group substituted with 1 to 3 substituents selected from substituent groups a and b, a C1-C10 alkylene group which has an oxygen atom or a sulfur atom in said carbon chain or at the end of said carbon chain, or a C1-C10 alkylene group which is substituted with 1 to 3 substituents selected from substituent groups a and b and has an oxygen atom or a sulfur atom in said carbon chain or at the end of said carbon chain;
• R5 represents a hydrogen atom, a cycloalkyl group, an aryl group, a heterocyclic group, a cycloalkyl group substituted with 1 to 3 substituents selected from substituent groups a and b, an aryl group substituted with 1 to 3 substituents selected from substituent groups a and b, or a heterocyclic group substituted with 1 to 3 substituents selected from substituent groups a and b;
• R6 and R7 are the same or different and each represent a hydrogen atom or a group selected from substituent group a;
• with the proviso that when R5 is a hydrogen atom, Y is not a single bond or a straight chain C1-C10 alkylene group;
• substituent group a consists of a halogen atom, a lower alkyl group, a halogenated lower alkyl group, a lower alkoxy group, a lower alkylthio group, a carboxyl group, a lower alkoxycarbonyl group, a hydroxyl group, a lower aliphatic acyl group, an amino group, a mono lower alkylamino group, a di lower alkylamino group, a lower aliphatic acylamino group, a cyano group, and a nitro group;
• substituent group b consists of a cycloalkyl group, an aryl group, a heterocyclic group, a cycloalkyl group substituted with 1 to 3 substituents selected from substituent group a, an aryl group substituted with 1 to 3 substituents selected from substituent group a, and a heterocyclic group substituted with 1 to 3 substituents selected from substituent group a.