Several Golgi targeting fluorescence markers based on 1,8-naphthalimide derivatives with amide and long carbon chain

As an important organelle, the main function of the Golgi apparatus is to further modify and deliver proteins synthesized by the endoplasmic reticulum (ER). Dyshomeostasis of the Golgi appartus can cause many serious diseases. Therefore, monitoring the normal functioning of the Golgi appartus is particularly important. However, only a few commercially Golgi markers are available till now. In this work, three 1,8-naphthalimide related Golgi markers ( 4a - c ) with the combination of amide and long carbon chain were designed and synthesized, their maximum emission wavelengths could reach 500–575 nm with high fluorescence quantum yields . Moreover, they possessed low cytotoxicity (cell viabilities >82%). Cell experiments exhibited that dyes 4a - c could rapidly and accurately mark the Golgi apparatus. To discuss the origin of their targeting ability, compounds 5–7 with independent amide or long carbon chain were additionally prepared. With the separation of amide and long carbon chain in compound 5 – 7 , the targeting ability was lost. The experiments showed that the targeting ability of 4a - c resulted from the combination of amide and long carbon chain structure. Also, the results may provide a new idea for designing organelle markers.