NAPHTHALENE DERIVATIVE

NEW MATERIAL:A compound shown by formula I [R and R are lower alkoxycarbonyl or R and R form group shown by formula II further R is H; R and R are lower alkoxy and one of R and R may be H; ring A is substituted or nonsubstituted benzene ring; with the proviso that when (a) R and R are COOCH3 and ring A is group shown by formula III, (b) R is H R is COOC2H5 and ring A is group shown by formula IV or (c) R and R are group shown by forming II and ring A is group shown by formula III IV, one of R and R is >=2C lower alkoxy or H] or a salt thereof. EXAMPLE:1-( 3,4-Dimethoxyphenyl )-2, 3-bis(methoxycarbonyl)-4-hydroxy-6,7,8-tri methoxynaphthalene. USE:An antilipemic agent which lowers a total cholesterol value in blood but raises HDL-cholesterol value. PREPARATION:A compound shown by formula V (R is R except group shown by formula II; R is lower alkyl) is reacted with a compound shown by formula VI or a lower alkylacetal derivative or a salt thereof to give a compound shown by formula I wherein R and R are not group shown by formula II.