Furfural was oxidized to furoic acid by molecular oxygen under catalysis by 150 nm-sized Ag2O/CuO (92%) or simply CuO (86.6%). When 30 nm-size catalyst was used, the main product was a furfural Diels-Alder adduct. Detailed reaction conditions and regeneration of catalysts were investigated. Under optimal conditions, a series of aromatic and aliphatic aldehydes were oxidized to the corresponding acids in good yields.

A series of 5-dialkyl(aryl)aminomethyl-8-hydroxyquinoline dansylates were synthesized and their fluoroionophoric properties toward representative alkali ions, alkaline earth ions and transition metal ions were investigated. Among the selected ions, Fe 3+ caused considerable quenching of the fluorescence, while Cr 3+ caused quenching to some extent. The absence of any significant fluorescence quenching effects of the other ions examined, especially Fe 2+ , renders these compounds highly useful Fe 3+ -selective fluorescent sensors.

A new “turn-on” fluorescent probe, composed of a protected phenol group with a p-nitrobenzyl moiety that functions as a latent donor and conjugated with two benzo[f]indolinium acceptors, was developed and applied for imaging nitroreductase (NTR) in hypoxic tumor cells.

A series of dendritic 8-hydroxyquinoline (8-HQ) and 5-dialkyl(aryl)amino-methyl -8-HQ derivatives were synthesized and their fluoroionophoric properties toward representative alkali, alkaline earth, group IIIA and transition metal ions were investigated. Among the selected ions, Zn(II) enhanced the fluorescence of N-di- (methoxycarbonylethyl)aminoethyl-3-[4-(8-hydroxyquinolin-5-ylmethyl)piperazin-1-yl]-propanoic amide] (7) by 31-fold, while Al(III) caused enhancement to some extent. The absence of any significant fluorescence enhancement by the other ions examined renders 7 a highly useful Zn(II)-selective fluorescent sensor.