NEW CROWN SPIROBENZOPYRANS AS LIGHT-RESPONSIVE AND ION-RESPONSIVE DUAL-MODE SIGNAL TRANSDUCERS

A new class of crown spirobenzopyrans were designed and synthesized. T he crown spirobenzopyrans showed thermally irreversible photochromism only in the presence of alkali-metal cations accompanying cation-selec tive coloring efficiency. Thus, the new crown spirobenzopyrans could t ransmit information of two different simultaneous stimuli (ion and pho ton) to changes in their optical properties. The dual-mode signal tran sducer molecules developed here can be considered to perform ''AND'' g ate type signal transduction based on photochromism of artificial rece ptors. Molecular recognition abilities and photochromic properties of the new crown spirobenzopyrans were characterized by use of NMR and FA B mass spectroscopies.