Patent ID: 7476754

Claim:
A compound of formula I, which has a 2,2′-disubstituted biphenyl structure, wherein: the group X is oxygen (O) or sulphur (S), indifferently, the groups R 1 and R 2 are the same or different and are independently selected from among the groups H, alkyl of between 1 and 10 carbon atoms, aryl, and arylalkyl, when applicable (that is, when R 1 or R 2 ≠ H), the asterisk (*) represents a stereogenic center, of configuration (R) or (S), indifferently, the groups R 3 and R 4 are the same or different and are independently selected from among the groups H, alkyl of between 1 and 6 carbon atoms, aryl, arylalkyl, NH 2 , NHR 5 in which R 5 represents an alkyl or aryl group, NR 6 R 7 in which R 6 and R 7 represent two alkyl or aryl groups, identical or different, or forming a cyclic system, OH, OR 8 in which R 8 represents an alkyl or aryl group; and any of the conformational isomers (atropisomers) of said compound of formula I.