The invention is concerned with novel heteroarylacetamides of formula (I) R.sup.d--C(O)--N(R.sup.e)--R.sup.c--CH.sub.2--C(O)--N(R.sup.a)(R.sup.b) (I) wherein R.sup.a to R.sup.e are as defined in the description and in the claims, as well as physiologically acceptable salts thereof. These compounds inhibit the coagulation factor Xa and can be used as medicaments.