Penam derivative or salt thereof, pharmaceutical composition, and applications thereof

A compound represented by General Formula [1] or a salt thereof,

• in the formula,
• R1 represents a hydrogen atom or a carboxyl protecting group;
• R2 represents an aryl group which may be substituted or a heterocyclic group which may be substituted;
• R3 represents a hydrogen atom or a carboxyl protecting group;
• X1 represents a C1-6 alkylene group which may be substituted, a C2-6 alkenylene group which may be substituted, a C2-6 alkynylene group which may be substituted, a divalent cyclic hydrocarbon group which may be substituted, or a divalent monocyclic saturated heterocyclic group which may be substituted;
• A represents a heterocyclic group which may be substituted;
• Q represents a divalent cyclic amino group which may be substituted or a divalent heterocyclic group which may be substituted;
• Y1 represents a C1-6 alkylene group which may be substituted, a C2-6 alkenylene group which may be substituted, a C2-6 alkynylene group which may be substituted, a group represented by Formula —N═CH—CH═N—, a group represented by Formula —N═CH—CH═N—O—, a group represented by Formula —N═CH—CH2—, a group represented by Formula —N═CHC(═O)—, a group represented by Formula —NHC(═O)—, a group represented by Formula —NHC(═O)CH2—, a group represented by Formula —NHC(═O)NH—, a group represented by Formula —NHC(═O)NH—O—, a group represented by Formula —NHC(═O)C(═O)NH—, a group represented by Formula —NHC(═O)C(═O)N(OH)—, a group represented by Formula —NHCH2C(═O)—, a group represented by Formula —NHS(═O)2NHC(═O)—, a group represented by Formula —NHC(═O)NHS(═O)2—, or a bond;
• X2 represents a group represented by General Formula —NR4— (where R4 represents a hydrogen atom, a carbamoyl group, a C1-6 alkyl group which may be substituted, or a hydroxyl group which may be protected), a group represented by General Formula —N+R5R6— (where R5 and R6 are the same as or different from each other and each represent a C1-6 alkyl group which may be substituted, or in combination represent a C2-6 alkylene group which may be substituted or a C2-6 alkenylene group which may be substituted), a group represented by General Formula —NR7—C(═O)—NR8— (where R7 and R8 are the same as or different from each other and each represent a hydrogen atom, a C1-6 alkyl group which may be substituted, or a hydroxyl group which may be protected), a divalent cyclic amino group which may be substituted, a divalent heterocyclic group which may be substituted, or a bond;
• Y2 represents a C1-6 alkylene group which may be substituted, a C2-6 alkenylene group which may be substituted, a C2-6 alkynylene group which may be substituted, or a bond;
• X3 represents a group represented by General Formula —NR9— (where R9 represents a hydrogen atom, a C1-6 alkyl group which may be substituted, or a hydroxyl group which may be protected) or a bond;
• and
• Y3 represents a group represented by Formula —C(═O)—, a group represented by Formula —C(═O)—C(═O)—, a group represented by General Formula —C(═O)—C(═NR10a)— (where R10a represents a C1-6 alkoxy group which may be substituted, a hydroxyl group which may be protected, or a ureido group), or a group represented by Formula —N═CR11a— (where R11arepresents a carbamoyl group which may be substituted or a carboxyl group which may be protected).