Isoxazole derivatives

A compound represented by the formula (II)

• wherein one of R1a and R2a is a hydrogen atom and the other is an optionally substituted cyclic group;
• Wa ia a divalent aliphatic hydrocarbon group selected from C1-8 alkylene or C2-6 alkenylene;
• Y is a group of the formula:
• —OR3,
• wherein R3 is a hydrogen atom, an optionally substituted aliphatic hydrocarbon group, an optionally substituted alicyclic hydrocarbon group, an optionally substituted aromatic hydrocarbon group, an optionally substituted aromatic aliphatic hydrocarbon group or an optionally substituted acyl group, or Y is an optionally esterified or amidated carboxyl group,
• wherein R1a, R2a, R3 and Y independently do not comprise heterocylce or heteroaryl,
• provided that when Wa is C1-3 alkylene and Y is a group of the formula:
• —OR3, wherein R3 is as defined above, or an optionally methylesterified carboxyl group, R1a should be a hydrogen atom and R2a should be an optionally substituted cyclic group, except 5-phenyl-4-isoxazolylmethanol and 5-phenyl-4-isoxazolylacetic acid, or a salt thereof.

A method for the treatment of diabetic complication in a mammal, which comprises administering to said mammal an effective amount of a compound represented by the formula (I)

• wherein one of R1 and R2 is a hydrogen atom, halogen atom or an alkyl group and the other is an optionally substituted cyclic group;
• W is a bond or a divalent aliphatic hydrocarbon group selected from C1-8 alkylene or C2-8 alkenylene;
• Y is a group of the formula:
• —OR3,
• wherein R3 is a hydrogen atom, an optionally substituted aliphatic hydrocarbon group, an optionally substituted alicyclic hydrocarbon group, an optionally substituted aromatic hydrocarbon group, an optionally substituted aromatic aliphatic hydrocarbon group or an optionally substituted acyl group, or Y is an optionally esterified or amidated carboxyl group,
• wherein R1, R2, R3 and Y independently do not comprise heterocylce or heteroaryl,
• or a salt thereof or a prodrug thereof.

A method for making a phermaceutical composition for treating diabetic complications, said method comprising combining a compound represented by the formula (I)

• wherein one of R1 and R2 is a hydrogen atom, halogen atom or an alkly group and the other is an optionally substituted cyclic group;
• W is a bond or a divalent aliphatic hydrocarbon group selected from C1-8 alkylene or C2-8 alkenylene)
• Y is a group of the formula:
• —OR3,
• wherein R3 is a hydrogen atom, an optionally substituted aliphatic hydrocarbon group, an optionally substituted alicyclic hydrocarbon group, an optionally substituted aromatic hydrocarbon group, an optionally substituted aromatic aliphatic hydrocarbon group or an optionally substituted acyl group, or Y is an optionally esterified or amidated carboxyl group,
• wherein R1, R2, R3 and Y independently do not comprise heterocylce or heteroaryl,
• or a salt thereof or a prodrug thereof with a pharmaceutically acceptable carriers, excipient or diluent.