5,17-diamino(2-pyridyl) methylphosphono-11,23-di-tret-butyl-26,28-dihydroxy-25,27-dipropoxycalix(4)arene
5,17-diamino(2-pyridyl) methylphosphono-11,23-di-tret-butyl-26,28-dihydroxy-25,27-dipropoxycalix(4)arene