The chemosenssor that consists of [$Zn_2$(1,3-bis[bis(2-pyridylmethyl)aminomethyl]benzene)]$^{4+}$ (receptor) and pyrecatechol violet (signaling unit) detects with naked eyes di- and tri-phosphates conjugated to nucleosides or in free forms. The blue color of the aqueous solution (pH 7.0) of the sensor turns to yellow upon exposing to the analytes.