Indole derivatives for the treatment of osteoporosis

Abstract

A compound of formula (I):or a salt thereof, or a solvate thereof, wherein Ra represents a group Rwhich is hydrogen, alkyl or optionally substituted aryl and Rb represents a moiety of formula (a):wherein X represents a hydroxy or an alkoxy group wherein the alkyl group may be substitued or unsubstituted or X represents a group NRRwherein Rand Reach independently represent hydrogen, alkyl, substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted arylalkyl, an optionally substituted heterocyclic group or an optionally substituted heterocyclylalkyl group, or Rand Rtogether with the nitrogen to which they are attached form a heterocyclic group; Rrepresents an alkyl or a substituted or unsubstituted aryl group; and R, Rand Reach independently represent hydrogen, alkyl, aryl or substituted aryl; Rand Reach independently represent hydrogen, hydroxy, amino, alkoxy, optionally substituted aryloxy, optionally substituted benzyloxy, alkylamino, dialkylamino, halo, trifluoromethyl, trifluoromethoxy, nitro, alkyl, carboxy, carbalkoxy, carbamoyl, alkylcarbamoyl, or Rand Rtogether represent methylenedioxy, carbonyldioxy or carbonyldiamino; and Rrepresents hydrogen, hydroxy, alkynoyl, alkyl, aminoalkyl, hydroxyalkyl, carboxyalky, carbalkoxyalkyl, carbamoyl or aminosulphonyl; a process for preparing such a compound, a pharmaceutical composition containing such a compound and the use of such a compound in medicine.