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.
Iwema Bakker, W. I., Haas, M., den Hertog Jr., H. J., Verboom, W., de Zeeuw, D., Bruins, A. P., & Reinhoudt, D. N. (1994). Functionalized calixspherands: synthesis and peptide coupling. Journal of organic chemistry, 59(5), 972-976. https://doi.org/10.1021/jo00084a011