A conference. Chelate complexes of amidinium cations with benzylic bisphosphonates represent a new highly efficient binding motif for this substance class. Since benzylic bisphosphonates are readily accessible by std. methods with inexpensive reagents, this moiety can easily be incorporated in new materials for the affinity chromatog. used for drug purifn. or isolation of precious natural products. Another potential application lies in the area of mol. imprinting: we suggest that polymerizable bisphosphonates constitute a new prototype of binding monomers with promising features for the selective recognition of amidinium substrates in the cavities of macroporous highly crosslinked imprinted copolymers.