N-HETEROCYCLIC PROPYLIDENE-1,1-BISPHOSPHONIC ACIDS, THEIR PRODUCTION AND A PHARMACEUTICAL COMPOSITION

摘要

The present invention relates to compounds of formula (I) in which R1-R8 can be the same or different and stand for hydrogen or a straight or branched aliphatic C1-C10 hydrocarbon radical. In addition, R3 when taken together with either R1 or R5 can form a saturated aliphatic 5-, 6- or 7-membered ring, which may be substituted with one or more C1-C4-alkyl radicals. The present compounds are effective e.g. in drugs influencing calcium metabolism.