Jakobsen P, Horobin R W
Department of Chemistry, Panum Institute, University of Copenhagen, Denmark.
Stain Technol. 1989 Nov;64(6):301-13. doi: 10.3109/10520298909107022.
4-Acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS) and other 4,4'-stilbene-2,2'-disulfonate derivatives used as reagents in histochemistry and physiology have been prepared in their E isomeric form, and rearranged to the Z isomers by irradiation with visible light. Infrared, and 1H and 13C nuclear magnetic resonance spectra were recorded for these compounds, and used to establish the chemical structures. In particular, it was shown that the E-isomer of SITS decomposed in aqueous solution by hydrolysis of both the acetamido and isocyano groups yielding a diamine; disodium 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS) also decomposed in solution, while disodium 4,4'-dinitrostilbene-2,2'-sulfonate (DNDS) rearranged from the E-isomer to the Z-isomer when solutions were kept unprotected from light. These results indicate that benchworkers should not be surprised when commercial samples of such stilbenes contain large amounts of various types of impurities.
4-乙酰氨基-4'-异硫氰基芪-2,2'-二磺酸（SITS）以及其他用作组织化学和生理学试剂的4,4'-芪-2,2'-二磺酸盐衍生物是以其E异构体形式制备的，并通过可见光照射重排为Z异构体。记录了这些化合物的红外光谱、1H和13C核磁共振谱，并用于确定化学结构。特别值得注意的是，SITS的E异构体在水溶液中通过乙酰氨基和异氰基的水解分解生成二胺；4,4'-二异硫氰基芪-2,2'-二磺酸钠（DIDS）在溶液中也会分解，而4,4'-二硝基芪-2,2'-二磺酸钠（DNDS）在溶液未避光保存时会从E异构体重排为Z异构体。这些结果表明，当此类芪类化合物的商业样品含有大量各种类型的杂质时，实验室工作人员不应感到惊讶。
