Patent ID: 7384974

Claim:
A 4,5-dihydronaphtho[1,2-b]thiophene derivative expressed by the formula: (wherein R 1 is a C 1 to C 10 1-hydroxyalkyl group or a C 1 to C 10 acyl group, and R 2 and R 3 separately substitute in the 6-, 7-, 8-, or 9-positions, and are each independently a hydrogen atom, a halogen atom, a C 1 to C 10 alkyl group, a hydroxy group, a C 1 to C 10 alkoxy group, a C 1 to C 5 alkenyloxy group, a C 1 to C 5 alkynyloxy group, a benzyloxy group, a nitro group, an acetyl group, or a group expressed by the formula —NR 4 R 5 (wherein R 4 and R 5 are each independently a hydrogen atom, an acetyl group, a trifluoroacetyl group, a C 1 to C 10 alkyl group, or a benzyl group), or R 2 and R 3 are bonded together to form an ethylenedioxy group, provided that when R 1 is an acyl group and R 2 is a hydrogen atom, then R 3 is neither a hydrogen atom nor an acetyl.