Compounds of formula pharmaceutically acceptable salts, solvates, solvates of such salts and prodrugs thereof and their use as cholesterol absorption inhibitors for the treatment of hyperlipidaemia are described. The rubber composition contains a polybutadiene having 60 wt % or more of cis-1,4-bonds and 40 or more of a Mooney viscosity ), unsaturated carboxylic acid andor a metal salt thereof, an organic peroxide, and a monophenol based antioxidant. This allows more efficient gas discharges in e.