Pharmaceutical applications for methanediphosphonate derivative

A method of treating diseases selected from the group consisting of rheumatism and bone metabolic disease, and for inhibiting patient physiological conditions selected from the group consisting of inflammation, interleukin-1 production, interleukin-1-induced cellular response, active oxygen production in neutrophils and bone resorption, comprising administering an effective amount of a methanediphosphonate derivative represented by formula (I):

• ##STR44## where, X represents H, a straight chain or branched chain alkyl group having 1 to 8 carbon atoms that is either unsubstituted or substituted, an aryl group, or an acyl group,
• Y represents a halogen atom, nitrile group, nitro group, alkyl group, alkoxy group, trifluoromethyl group, hydroxyl group, acyloxy group, acylamino group, acyl group, alkenyl group, aryl group, cycloalkyl group, COOH group, COO-alkyl group, ##STR45## (wherein Z.sup.1 and Z.sup.2 represent, independently of each other, hydrogen atoms or alkyl groups, or Z.sup.1 and Z.sup.2 may form a ring composed of carbon atoms or a ring composed of carbon atoms containing hetero atoms) or ##STR46## (wherein Z.sup.1 and Z.sup.2 represent the same groups as indicated above, and Z.sup.3 represents oxygen or sulfur),
• m represents an integer of 1 to 5, n represents an integer of 0 to 4 (provided that m+n is 5 or less), the m number of XS and the n number of Y may be either identical or different, respectively,
• . . represents a double bond or a single bond,
• A is --(CH.sub.2)a-(D)b-(CH.sub.2)c- (D is sulfur, oxygen, NH, alkyl-substituted N or CH.sub.2, a and c are integers of 0 to 10, and b is 0 or 1), or --(CH.dbd.CH)d-CH.dbd. (d is an integer of 0 to 2, and B does not exist in the case when A represents --(CH.dbd.CH) d-CH.dbd.,
• B represents a hydrogen atom, an alkyl group, amino group, monoalkylamino group, dialkylamino group, acylamino group, hydroxyl group, an alkoxy group, trialkylsiloxy group or acyloxy group, and
• R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are identical or different, and are hydrogen atoms, straight or branched chain alkyl groups having 1 to 7 carbon atoms or pharmaceutically acceptable cations.