Heterocyclic compound

A compound represented by the formula:

• wherein
• R1 is an optionally substituted C1-6 alkylsulfonyl group, an optionally substituted mono- or di-C1-6 alkylaminosulfonyl group, an optionally substituted 3- to 6-membered cyclylsulfonyl group, a formylcarbonyl group, a carboxycarbonyl group, a carbamoylcarbonyl group, an optionally substituted C1-6 alkyl-carbonyl group, an optionally substituted C1-6 alkoxy-carbonyl group, an optionally substituted mono- or di-C1-6 alkyl-carbamoyl group, an optionally substituted C1-6 alkyl-carbonyl-carbonyl group, an optionally substituted C1-6 alkoxy-carbonyl-carbonyl group, an optionally substituted mono- or di-C1-6 alkyl-carbamoyl-carbonyl group or an optionally substituted 3- to 6-membered cyclylcarbonyl group;
• R2 and R3 are each independently a hydrogen atom, an optionally substituted C1-6 alkyl group or a halogen atom;
• X is an optionally substituted methylene group or an oxygen atom;
• Y and Z are each independently a carbon atom or a nitrogen atom;
• Ring A is an optionally substituted 5- or 6-membered nitrogen-containing aromatic heterocycle;
• L is an optionally substituted methylene group, an oxygen atom, —O-L1-, -L1-O— or -L1-L2-;
• L1 and L2 are each independently an optionally substituted methylene group;
• and
• Ring B is an optionally further substituted 4- to 7-membered ring,
• or a salt thereof.