The invention relates to a compound comprising at least two —(NH—C═O)— groups and at least two —(C═O)—C≡C—R1 groups, wherein R1 represents hydrogen or a group having from 1 to 12 carbon atoms; a curable composition comprising a first unit comprising at least two —(NH—C═O)— groups, a second unit comprising at least two —(C═O)—C≡C—R1 groups, and a catalyst; and the use of the composition as an adhesive, coating, casting composition or as sealant.