Patent ID: 6960586

Claim:
A compound represented by the formula: wherein R is (i) a hydrogen atom, (ii) a formyl group or (iii) a C 1-6 alkylcarbonyl group, a phenylcarbonyl group, a C 1-6 alkyl-oxycarbonyl group, a C 2-6 alkenyl-oxycarbonyl group, a phenyloxycarbonyl group, a C 7-10 aralkyloxy-carbonyl group, a trityl group, a phthaloyl group, or an N,N-dimethylaminomethylene group, each of which optionally has 1 to 3 substituents selected from the group consisting of a halogen atom, a formyl, a C 1-6 alkyl-carbonyl and a nitro, R 1 is a lower alkyl group or a cyclic alkyl group, and ring A and ring B are each a 5-membered or 6-membered ring having an amide bond in the ring, optionally having a substituent selected from the group consisting of (1) a C 1-10 linear or branched chain hydrocarbon group optionally having 1 to 5 substituents selected from the group consisting of (a) a halogen atom, (b) a hydroxyl, (c) a C 1-10 alkoxy, (d) an acyloxy, (e) a C 1-10 alkylthio, (f) an acylamino, (g) a carboxyl, (h) a C 1-10 alkoxycarbonyl, (i) an oxo, (j) a C 1-10 alkylcarbonyl, (k) a C 3-10 cycloalkyl, (l) a C 6-14 aryl, and (m) a 5 to 10-membered mono- to tri-cyclic aromatic heterocyclic group containing, besides the carbon atom, 1 or 2 kinds of hetero atoms selected from the group consisting of nitrogen, oxygen and sulfur, (2) a C 3-18 cyclic hydrocarbon group optionally having 1 to 5 substituents selected from the group consisting of (a) a halogen atom, (b) a hydroxyl, (c) a C 1-10 alkoxy, (d) an acyloxy, (e) a C 1-10 alkylthio, (f) a C 1-10 alkylsulfonyl, (g) a mono- or di-C 1-4 alkylamino, (h) an acylamino, (i) a carboxyl, (j) a C 1-10 alkoxycarbonyl, (k) a C 3-10 alkynylcarbonyl, (l) a C 1-10 alkyl, (m) a C 3-10 cycloalkyl, (n) a C 6-14 aryl, and (o) a 5 to 10-membered mono- to tri-cyclic aromatic heterocyclic group containing, besides the carbon atom, 1 or 2 kinds of hetero atoms selected from the group consisting of nitrogen, oxygen and sulfur, (3) an amino group, (4) a C 1-4 alkylamino group, (5) a di-C 1-4 alkylamino group, and (6) a C 1-4 alkanoylamino group, or a salt thereof.