The present invention relates to new CGRP-antagonists of general formula I wherein U, V, X, Y, R1, R2, R3 and R4 are defined as mentioned in the description, the tautomers thereof, the isomers thereof, the diastereomers thereof, the enantiomers thereof, the hydrates thereof, the mixtures thereof and the salts thereof as well as the hydrates of the salts, particularly the physiologically acceptable salts thereof with inorganic or organic acids or bases, medicaments containing these compounds, the use thereof and processes for the preparation thereof.