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In this study, the ligands 23,24-dihydroxy-3,6,9,12-tetraazatricyclo[17.3.1.1(14,18)]eicosatetra-1(23),14,16,18(24),19,21-hexaene, <b>L1</b>, and 26,27-dihidroxy-3,6,9,12,15-pentaazatricyclo[20.3.1.1(17,21)]eicosaepta-1(26),17,19,21(27),22,24-hexaene, <b>L2</b>, were synthesized: they represent a new class of molecules containing a biphenol unit inserted into a macrocyclic polyamine fragment. The previously synthesized <b>L2</b> is obtained herein with a more advantageous procedure. The acid-base and Zn(II)-binding properties of <b>L1</b> and <b>L2</b> were investigated through potentiometric, UV-Vis, and fluorescence studies, revealing their possible use as chemosensors of H⁺ and Zn(II). The new peculiar design of <b>L1</b> and <b>L2</b> afforded the formation in an aqueous solution of stable Zn(II) mono (LogK 12.14 and 12.98 for <b>L1</b> and <b>L2</b>, respectively) and dinuclear (LogK 10.16 for <b>L2</b>) complexes, which can be in turn exploited as metallo-receptors for the binding of external guests, such as the popular herbicide glyphosate (<i>N</i>-(phosphonomethyl)glycine, PMG) and its primary metabolite, the aminomethylphosphonic acid (AMPA). Potentiometric studies revealed that PMG forms more stable complexes than AMPA with both <b>L1</b>- and <b>L2</b>-Zn(II) complexes, moreover PMG showed higher affinity for <b>L2</b> than for <b>L1</b>. Fluorescence studies showed instead that the <b>L1</b>-Zn(II) complex could signal the presence of AMPA through a partial quenching of the fluorescence emission. These studies unveiled therefore the utility of polyamino-phenolic ligands in the design of promising metallo-receptors for elusive environmental targets.