Calix[4]API‑s: fully functionalized calix[4]arene‑based facial active pharmaceutical ingredients

This mini-review covers 25 fully functionalized facial calix[4]arene-based symmetrical and conical cyclic tetramers with
significant (comparable to established therapeutic agents) anticancer and anti-infective activities. The main role of the
calixarene scaffold in these calix[4]arene-based active pharmaceutical ingredients (calix[4]API-s) is to replicate embedded
phenolic units in the cyclic tetramers. So, probably owing to the multivalency, facial, conical structures of calix[4]API-s and
synergistic effect of their four replicated units, they can be considered as effective bioactive agents.