Sensitive fluorescent sensors for malate based on calix[4]arene bearing anthracene

Two chiral fluorescence receptors 3a and 3b based on calix[4]arenes were synthesized, and their chiral recognition properties for enantiomeric malate were studied by fluorescence and 1H NMR spectra in CHCl3. The addition of either l- or d-malate caused obvious fluorescence quenching of the host solution. Different fluorescent responses demonstrate that the two receptors have good enantioselective recognition abilities towards malate.

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5,11,17,23-Tetra-4-tert-butyl-25,27-bis((S)-2-acetamido-N-(3-aminopropyl)propanamide)-26,28-dihydroxycalix[4]areneC60H86N6O8[α]D20=+5.2 (c 0.015, CHCl3)Source of chirality: chiral poolAbsolute configuration: (S,S)

5,11,17,23-Tetra-4-tert-butyl-25,27-bis((S)-2-acetamido-N-(3-aminopropyl)-3-phenylpropanamide)-26,28-dihydroxycalix[4]areneC72H94N6O8[α]D20=-11.3 (c 0.015, CHCl3)Source of chirality: chiral poolAbsolute configuration: (S,S)

5,11,17,23-Tetra-4-tert-butyl-25,27-bis((S)-2-acetamido-N-(3-(anthracen-10-ylmethylamino)propyl)propanamide)-26,28-dihydroxycalix[4]areneC90H106N6O8[α]D20=-12.5 (c 0.015, CHCl3)Source of chirality: chiral poolAbsolute configuration: (S,S)

5,11,17,23-Tetra-4-tert-butyl-25,27-bis((S)-2-acetamido-N-(3-(anthracen-10-ylmethylamino)propyl)-3-phenylpropanamide)-26,28-dihydroxycalix[4]areneC102H114N6O8[α]D20=-36.2 (c 0.015, CHCl3)Source of chirality: chiral poolAbsolute configuration: (S,S)