Xanthinderivater, mellemprodukter og anvendelse til behandling af osteoporose

摘要

The invention concerns xanthine derivatives of formula (I) and their salts wherein: R1 represents a monocyclic or polycyclic system containing 0, 1, 2, 3 or 4 substituted or unsubstituted heteroatoms; R2 = H, R4, -(CH2)n-R4 or (CH2)m-O-R4, with R4 = R1 or substituted or unsubstituted alkyl; R3 = H; n and m = 1, 2 or 3. The invention also concerns the method for preparing said derivatives and intermediates of said method, their use as medicine and pharmaceutical compositions containing them.