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The upper-rim 1,3-alternate tetraoxacalix[2]arene[2]triazine azacrowns were constructed effectively bymacrocyclic condensation reaction of diamines with dichlorinated tetraoxacalix[2]arene[2]triazineintermediates that were synthesized from the stepwise fragment coupling reactions of 3,5-dihydroxybenzoicacid esters with cyanuric chlorides. Because of the formation of conjugation of amino groups with triazinerings, tetraoxacalix[2]arene[2]triazine azacrowns existed in a mixture of syn
- and anti
-isomeric forms.Both fluorescence titration and
1H NMR spectroscopic study showed that tetraoxacalix[2]arene[2]triazineazacrowns interacted with fluoride anion, leading to cavity changes of the host molecules.