Fluorescent anion sensor derived from cholic acid: the use of flexible side chain.
[structure: see text] The fluorescent photoinduced electron transfer (PET) chemosensors 1-3 were synthesized from cholic acid. 1 and 2 containing amidothiourea groups as anion receptive sites demonstrated much higher affinity toward anions than 3 containing traditional thiourea H-bond donating group. Comparative studies on their binding affinity toward carboxylates, dihydrogen phosphate, and halides revealed that the amidothiourea moiety on the C17 side chain could work cooperatively with H-bond donating groups on C7 and C12 to bind spherical halogen anions. An unexpected specific fluorescence enhancement of 1 by coordinating bromide ion was observed.
Fang
Lei
L
Department of Chemistry and Central Laboratory of the Institute of Molecular Technology for Drug Discovery and Synthesis, Hong Kong Baptist University, Hong Kong SAR, PR China.
Chan
Wing-Hong
WH
He
Yong-Bing
YB
Kwong
Daniel W J
DW
Lee
Albert W M
AW
D000838:Anions / Q000032:analysis*; D015374:Biosensing Techniques / Q000379:methods*; D002793:Cholic Acids / Q000138:chemical synthesis*; D005453:Fluorescence; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy
D000838:Anions; D002793:Cholic Acids