Compounds of the formula I R.sup.1--O--CO--C(.dbd.CHR)--Y--O-Q(AH).sub.n (I) whereA stands for a --CO.sub.2-- or --SO.sub.3-- group which together with H.sup.+ yields AH,Q represents C.sub.1-12alkylene, C.sub.4-12alkylene interrupted by --O--, >N--, or --S--, or, in given cases, C.sub.6-15arylene substituted with C.sub.1-4alkyl, C.sub.1-4alkoxy or halogen, where in the case of arylene the aryl groups can carry additional acid groups A,Y stands for C.sub.1-12alkylene or C.sub.4-12alkylene interrupted by --O--, >N--, or --S--,R represents methyl or H,R.sup.1 is C.sub.1-6alkyl, andn assumes the values 1, 2, or 3are particularly suitable for the production of self-etching dental adhesives.