Preliminary Synthetic Research Of Novel NIR-Ⅱ Azobenzene-containing Photochromic Fluorescent Small Molecules And Design Of F16 Derivatives

Molecular imaging is a highly interdisciplinary comprehensive subject,and the biological imaging technology is widely used in clinical medicine and new drug discovery.Compared to other medical imaging,NIR-Imaging tech has a lower cost,a shorter application period,a higher biocompatibility,a better resolution and easier for real-time controlling,and thus become a hot issue in the file of medical imaging.One of the key tech of NIR-Imaging is the materials used for imaging.Organic small molecules are the best candidate materials for near infrared imaging because of their characteristics of easily modified,easily metabolized and controllable optical properties.On the basis of a large number of previous studies,we have designed a series of D-A-D type Piazthiole-based azobenzene-containing conjugated fluorescent compounds.In the attempt toward these compounds,we’ve found and synthesized the ZW series and the DA series compounds which exhibit an ideal NIR optical properties.Both of the fluorescent spectra of these compounds lie in the NIR-I biological window of 700-850 nm.Considering their simple synthetic route and required for cheaper materials,we thought they have the potential of commercial production.We have designed a series of derivatives of the anti-tumor small molecule—F16,and the feasibility of the synthetic route was confirmed by our preliminary investigation on their synthesis.Two of the F16 derivatives,F16-Dland F16-D18,exhibit overwhelming fluorescent imaging properties and tumor-cell-targeting abilities.In summary,the ZW series compounds we synthesized have relatively new structure frame,which provides an effective reference for further development of small molecule NIR fluorescent probes.DA series compounds exhibit excellent optical properties in the NIR-I window,and we believed they can be used for NIR-I fluorescence imaging with proper modification.A preliminary inquiry into the synthesis of the F16 derivatives confirms the feasibility of our synthetic design,and two of them showed excellent fluorescence labeling ability on tumor cells.With a further optimization,these derivatives may could be used in fluorescence-image-guided tumor ejection surgery.