Abstract: The invention concerns biotin derivatives of general formula (I), wherein: R1 represents a specific compound; X1 represents a carbonaceous chain, preferably of 1 to 10 carbon atoms, substituted or not, optionally comprising one or several carbonyl or oxycarbonyl groups, and/or a —NH— group, in particular a chain of formula —HN(CH2)n—O—CO wherein n is an integer between 1 and 5 and optionally comprising one or several ether, amide and/or amino functions; Y represents a hydrocarbon chain of 1 to 5 carbon atoms, substituted or not; R2 represents a hydrogen atom, or a protecting group, in particular R2 represents an alkyl group of 1 to 5 carbon atoms. The invention is useful as vectors, in particular for implementing methods for detecting interactions between biological compounds, and in pharmaceutical compositions.