Patent ID: 8889732

Claim:
A compound of formula (I): a tautomer, or a pharmaceutically acceptable salt of the compound, wherein: A is CH; B is a sulfur atom; R 1 is an indanyl group; L 1 and L 2 are single bonds; L 3 is NH; X is OH; R 2 is a hydrogen atom or a C 1-6 alkyl group; and either L 4 is a single bond; Y is an oxygen atom; and R 3 is a thienyl group substituted with a substituent selected from the group consisting of a carboxy group and a C 1-6 alkoxycarbonyl group or R 3 is a phenyl group substituted with a carboxy group or a C 1-6 alkoxycarbonyl group and optionally further substituted with a nitro group; or L 4 is NH; Y is a sulfur atom; and R 3 is a phenyl group substituted with a carboxy group or a C 1-6 alkoxycarbonyl group and optionally further substituted with a halogen group.