To provide a new benzofuran derivative useful as a bone resorption suppressing agent and a bone metastasis suppressing agent for the prevention and treatment of bone diseases characterized by bone dysbolism such as osteoporosis.
The objective compound is expressed by the formula I (R1 is formyl, a carbomyl-lower alkyl, a thiomorpholinocarbonyl-lower alkyl-S-oxide, a pyridylaminocarbonyl-lower alkyl, etc.; R2 is a lower alkyl, a protected carboxy, etc.; R3 is a halogen or a lower alkyl; R4 is H, nitro, etc.; R5 is a halogen, a lower alkyl, etc.) or its salt, e.g. 7-(2,6-dichlorobenzoylamino)-2- ethoxycarbonyl-3-methylbenzo[b]furan. The compound of the formula I can be produced by reacting a compound of the formula II, its reactive derivative at the carboxyl group or their salts with a compound of the formula III or its reactive derivative at the amino group.
SATO SHIGEKI
YAMAZAKI HITOSHI
KAYAKIRI NATSUKO
YOSHIHARA KOSEI
OKU TERUO
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