Chiral selectors for separating enantiomers of a compound

A chiral selector for separating the enantiomers of a compound, comprising:

• a) at least one compound of formula (I):
• in which:
• W represents a bond, CR4R5, NR4, O or S;
• X represents CR6R7, NR6, O or S;
• Y represents CR8R9, NR8, O or S;
• Z represents CR10R11, NR10, O or S;
• R1 represents OH or SH;
• and
• R2, R3, R4, R5, R6, R7, R8, R9, R10, and R11, which are identical or different, represent:
• H;
• OH, SH;
• an amine group;
• an alkyl, haloalkyl or heteroalkyl group containing between 1 and 30 carbon atoms in a linear or branched chain;
• an alkenyl or alkynyl group containing between 2 to 30 carbon atoms in a linear or branched chain;
• one or more cycloalkyl, cycloalkenyl or cycloalkynyl groups containing between 3 to 30 carbon atoms in a linear or branched chain;
• one or more aryl or heteroaryl groups containing between 3 to 10 carbon atoms per ring;
• an alkaryl or aralkyl group containing between 1 and 30 carbon atoms, the terms aryl and alkyl having the definitions above;
• an alkoxy, thioalkyl, sulfonylalkyl or aminoalkyl group containing between 1 and 30 carbon atoms in a linear or branched chain;
• an alkoxyalkyl, alkylthioalkyl, alkylsulfonylalkyl or alkylaminoalkyl group containing between 1 and 30 carbon atoms in a linear or branched chain;
• one or more heterocyclic groups containing between 5 and 10 carbon atoms per ring;
• said groups all being optionally substituted by R2, by one or more nitro, cyano, hydroxyl, carboxyl, carbonyl or amino groups, by one or more halogens or by one or more nitrile, cyanohydrin or aldehyde functions;
• the compound of formula (I) being other than chitosan, neomycin, neomycin B, kanamycin A, kanamycin B, neamine, and amikacin;
• and
• b) at least one metal ion.