Hydrocarbons having two or more rings connected in the manner of links of a chain, without a covalent bond. More generally, the class catena compounds embraces functional derivatives and hetero analogues, e.g:, Süsivesinikud, mille molekul koosneb kahest või enamast tsüklilisest ahelast, mis on põimunud omavahel kovalentseid sidemeid moodustamata