Functionalized Calixspherands: Synthesis and Peptide Coupling

Calixspherands, like 1, form kinetically stable complexes with alkali metal cations. For practical in vivo applications coupling of these complexes with carrier molecules is mandatory, Therefore, a general method for the synthesis of functionalized calixspherand 17 was developed starting from functionalized m-terphenyl 10 and p-tert-butylcalix[4]arene (14). The functionalized m-terphenyl was synthesized by a Suzuki-cross-coupling reaction. Functionalized calixspherand 17 has been coupled to a low molecular weight protein.