C
C 2 -C 5 -Alkyl-substituted [(imidazol-1-yl)-1-hydroxy-1-phosphono-ethyl]-phosphonic acids, as well as methods or processes for their manufacture, their use in the manufacture of pharmaceutical formulations, their use in the treatment of diseases, methods of using them in the treatment of diseases, pharmaceutical formulations encompassing them and/or the compounds for use in the treatment of diseases, are described. The compounds are able to inhibit excessive or inappropriate bone resorption and for the treatment of other diseases which are caused by excessive prenylation of target proteins, such as Hutchinson-Gilford progeria syndrome. The compounds are of the formula I, wherein one of R 1 and R 2 is hydrogen and the other is C 2 -C 5 -alkyl that is branched or unbranched, and can be in free form, in the form of an ester, and/or of a salt.
1. A compound of the formula I,
wherein one of R 1 and R 2 is hydrogen and the other is ethyl, or an ester, and/or a salt thereof.
2. A compound of the formula I according to claim 1 wherein
R 1 is hydrogen and
R 2 is ethyl,
or an ester thereof, and/or a salt thereof.
3. A compound of the formula I according to claim 1 , wherein
R 1 is ethyl and
R 2 is hydrogen,
or an ester thereof, and/or a salt thereof.
4. A pharmaceutical composition, comprising a compound of the formula I, an ester and/or a pharmaceutically acceptable salt thereof, according to claim 1 and at least one pharmaceutically acceptable carrier.
5. A method of treatment of osteopenia, osteomyelitis, osteoarthritis, rheumatoid arthritis, bone marrow edema, bone pain, reflex sympathetic dystrophy, ankylosing spondylitis, Paget's disease, or hypercalcemia of malignancy in an animal, the method, comprising the step of administering to the animal an amount of a compound of the formula I, an ester and/or a pharmaceutically acceptable salt thereof, according to claim 1 .