Novel compounds of the formula I (I), in which R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, R.sup.12, R.sup.13, R, Q, W, X and Z have the meanings indicated in Patent Claim 1, are suitable as antidiabetics.