Compounds of the formula (I): in which R, R.sup.1 and R.sup.2 are as defined in the description, the use thereof for the treatment of dyslipidaemia, atherosclerosis and diabetes, pharmaceutical compositions comprising them, and . processes for the preparation of these compounds. Compounds of formula (I) are activators of PPAR.alpha. and PPAR.alpha. isoforms. ##STR00001##