NEW CALIXARENE HOSTS SYNTHESIZED WITH NATURAL CHEMICALS OF VANILLIN AND SYRINGALDEHYDE FOR FLUORESCENT CHEMO-PROBES TO HEAVY METAL ION

摘要

Recently, host-guest is well known as selective separator for chemicals. Especially, calixarenes are famous representative molecules synthesized from resorcinol and formyl chemical by compensated reaction as molecule host. In the present work, vanillin and syringaldehyde (S), which are chemical sources from lignin, are used to synthesize new calixarene hosts. For example, vanillin and S can be obtained from vanilla seed and pine tree as natural chemicals, respectively. These effective uses are meaningful in the point of view of sustainable chemistry. The new V-host and S-host and also reference hosts synthesized from p-hydroxybenzaldehyde (PH) and 3, 5-dimethoxybenzaldehyde (DM) were similarly prepared by dissolving resorcinol and vanillin S, PH and DM in ethanol for V-, S-, PH- and DM-host, respectively. The yields of the new hosts of V, S, PH and DM were 32%, 28%, 37% and 55%, respectively. These hosts were characterized by ~1H-NMR and FT-IR. From these results, it could be confirmed that these hosts were successively obtained. Change in UV-VIS spectra and fluorescence one of their hosts was indicated that the hosting of heavy metal ions such as Pb~(2+), Ni~(2+), Cd~(2+) and Cu~(2+) was confirmed to their inclusion ions. UV species at the phenyl ring groups in the spectra of the calixarene were increased when increase in the addition of each heavy metal ion. Especially, Pb~(2+) enhanced the absorbance intensity at 220 nm in the UV spectra. In addition, calixarenes showed enhanced fluorescence, when Pb~(2+) was added, except for S-host. These results reacts are evidenced that these new calixarene hosts are candidated to be fluorescent chemo-probe for lead ion diagnosis.