Phenol substituted gem-diphosphonate derivative, its preparation and pharmaceutical composition containing the same

NEW MATERIAL: A compd. represented by formula I {wherein Z 1 -Z 4 are OR (wherein R is H or 1-8C alkyl, OM [wherein M is alkali (±) metal ion], X 1 and X 2 are H, halogen, 1-8C alkyl or alkoxy, X 3 is H 1-8C alkyl R 1 or acyl C(o)R 1 , A is -CH=CH-CH 2 - or -(CH 2 ) n -(n; 1-7), B is H or 1-4C alkyl and t is 0 or 1}. EXAMPLE: Tetraetyl 2-(3,5-di-sec-butyl-4-hydroxyphenyl)-ethylidene-1,1- diphosphonate. USE: A treatment agent of hyperlipidemia and a treatment agent of cardiovascular diseases accompanied by hyperlipidemia. PROCESS: A compd. represented by formula II (wherein Y is Cl, Br or a group represented by formula III) is reacted with a disphosphonate compd. represented by formula IV in the presence of a base. COPYRIGHT: (C)1990,JPO