Design and Synthesis of A Caged Zn2+ Probe, 8-Benzenesulfonyloxy-5-N,N-dimethylaminosulfonylquinolin-2-ylmethyl-pendant 1,4,7,10-Tetraazacyclododecane, and Its Hydrolytic Uncaging upon Complexation with Zn2

• Published in: Inorganic chemistry Vol. 47; no. 7; pp. 2747 - 2754
• Main Authors: Aoki, Shin, Sakurama, Kazusa, Ohshima, Ryosuke, Matsuo, Nanako, Yamada, Yasuyuki, Takasawa, Ryoko, Tanuma, Sei-ichi, Takeda, Kei, Kimura, Eiichi
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 07.04.2008
• Subjects: Cadmium - chemistry; Cations, Divalent - chemistry; Fluorescent Dyes - chemistry; Heterocyclic Compounds, 1-Ring - chemical synthesis; Heterocyclic Compounds, 1-Ring - chemistry; Hydrogen - chemistry; Hydrogen-Ion Concentration; Hydrolysis; Magnetic Resonance Spectroscopy; Molecular Structure; Spectrophotometry; Sulfur Compounds - chemistry; Zinc - chemistry
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/ic702002m

8-Benzenesulfonyloxy-5-N,N-dimethylaminosulfonylquinolin-2-ylmethyl-pendant cyclen (BS-caged-L4, BS = benzenesulfonyl) was designed and synthesized as a “caged” derivative of a previously described Zn2+ fluorophore, 8-hydroxy-5-N,N-dimethylaminosulfonylquinolin-2-ylmethyl-pendant cyclen (L4) (cyclen = 1,4,7,10-tetraazacyclododecane). In the absence of metal ions and in the dark, BS-caged-L4 (10 µM) showed negligible fluorescence emission at pH 7.4 (10 mM HEPES with I = 0.1 (NaNO3)) and 25 °C (excitation at 328 nm). Addition of Zn2+ induced an increase in the UV/vis absorption of BS-caged-L4 (10 µM) at 258 nm and a significant increase in fluorescence emission at 512 nm. These responses are results from the formation of Zn(H−1L4) by the hydrolysis of the sulfonyl ester at the 8-position of the quinoline unit promoted by the Zn2+-bound HO−. Improvement of cell membrane permeation in comparison with L4 is also described.