Synthesis of a new bis-porphyrinic system coupled with biphenyl-20-crown-6 as an allosteric spacer, 1, is described; the incorporated rotatable biphenyl unit is capable of regulating the porphyrin center-to-center distance by an encapsulated metal ion in the crown-strapped cavity, so that the system displayed a potentially heterotropic allostery at the binding stage with a certain stereogenic α,ω-diamine