A new strapped calix[4]pyrrole containing a fluorophore as part of the strap has been synthesized and characterized. Association constants with various anions have been determined using both fluorescence titration and isothermal titrations calorimetry (ITC). The two sets of association constants were found to be in good agreement with one another. The fluorescence emission properties of this new receptor could be controlled by addition of Na+ (or H2O) and anions. However, the fluorescence quenching by anions is only observed in the presence of Na+ (or H2O). All the experimental evidence is consistent with the notion that independent PET processes are modulated by separate cation and anion recognition events. As such, this system operates as an elementary logic gate wherein anion and cation concentrations serve as the input and fluorescence intensity changes provide the output.

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1H and 13 C NMR spectra of series of (E)-1-aryl-(2-and 3-thienyl)-2-propenones, that are aldol condensation products between 2-and 3-thiophenecarbaldehydes and m-and p-substituted acetophenones, were examined to make complete assignments of the chemical shifts. Long range couplings, 4 J and 5 J, are observed in the 1 H-1 H COSY of both 2-and 3-thienyl compounds, which makes the elucidation of the conformation in solution possible. In contrast, the 2-furyl analogue shows the long range coupling phenomena, but the 3-furyl and phenyl analogues do not show similar phenomena.

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