Mutsuo Tanaka, Kenji Kamada, Hisanori Ando, Takashi Kitagaki, Yasuhiko Shibutani, Setsuko Yajima, Hidefumi Sakamoto and Keiichi Kimura
A spirobenzothiapyran derivative bearing a monoaza-12-crown-4 moiety affords significant thermal stability enhancement in the UV light induced colored merocyanine form of its photochromic moiety by metal-ion complexation of its crown ether moiety, although the complexation hardly induces the isomerization without photoirradiation.