Patent ID: 8183273

Claim:
A compound of the formula: or a salt thereof, wherein R 1 is a cyclic 5- to 6-membered ring which may be substituted; X 1 is a bond; rings A and B, together with the variables a, b, E 1 , E 2 , E 3 , and E 4 , form a benzoazocine ring system; X 2 is a bivalent chain group whose straight chain moiety is constituted of 1 to 4 atoms; Z 1 is a bond or a bivalent cyclic group; Z 2 is a bond or a bivalent group; and R 2 is (1) an amino group which may be substituted and whose nitrogen atoms may be converted to quaternary ammonium or oxide, (2) a nitrogen-containing heterocyclic group which may be substituted, may contain a sulfur or oxygen atom as a ring constituent atom, and whose nitrogen atom may be converted to quaternary ammonium or oxide, (3) a group of the formula: wherein k is 0 or 1; when k is 0, the phosphorus atom may form a phosphonium salt; each of R 5 and R 6 is a hydrocarbon group which may be substituted, a hydroxy group or an amino group which may be substituted; and R 5 and R 6 may form a ring with the adjacent phosphorus atom, (4) an amidino group which may be substituted, or (5) a guanidino group which may be substituted; or a salt thereof, provided that a compound of the formula: wherein ring A 1 is a benzene ring which is substituted by R 1 —X 1 —; R 1 is a cyclic 5- to 6-membered ring which may be substituted; X 1 is a bond; Y 1 is a bivalent group so that rings A 1 and B 1 together with Y 1 form a benzoazocine ring system; Q 1 is a group of the formula: wherein X is a bond or a bivalent group; R 1 and R 2 are hydrogen, and Q 2 is hydrogen, is excluded.