NEW MATERIAL:A compound expressed by formula I {ring A represents sulfur- containing or oxygen-containing heteromonocyclic group optionally oxygen- containing heteromonocyclic group optionally having substituent group; ring B represents formula II or III [R4 represents (substituted) lower alkyl]; R1 to R3 represent H, halogen, lower alkoxy, etc.; Y represents methylene or carbonyl}.
EXAMPLE: 2-Formyl-4-oxo-γ-5-hydroxymethyl-t-7-(3,4-dimethoxyphen-yl)-4,5,6,7-te- trahydrobenzo[b]furan-c-6-carboxylic lactone.
USE: A therapeutic and prophylactic agent for liver disorder.
PREPARATION: A tetrahydrobiphenyl compound (salt) expressed by formula IV is treated with a fluorine ion donor and a salt thereof, as desired, is formed to afford the compound expressed by formula I wherein the ring B represents a group expressed by formula II.
SUGIURA MASAKI
MATSUOKA YUZO
MATSUMOTO MAMORU
KITAMURA KAZUYUKI
