Syntheses of new reactive fluorescent dyes 5-carboxy- sulforhodamines under microwave irradiation

ORGN 623

Zhi Qiang Wang, Zhenjun Diwu, George G. Yi, and Jennie Francisco. Molecular Devices Corporation, 1311 Orleans Drive, Sunnyvale, CA 94089
The application of regioisomerically pure fluorescent probes has been widely explored in biology such as labeling a biological molecule, locating proteins in living cells, detecting a specific functional fragment of proteins and measuring an intracellular ion concentration. In this presentation, a series of new reactive 5-carboxy-sulforhodamines have been synthesized with a relatively new tool of the microwave-accelerated synthesis. When 4-carboxy-2-sulfobenzaldehyde reacts with various N-substituted 3-aminophenols under microwave irradiation in DMF and TFA (10%), the condensation reaction generated a desired product with the cleaner products compared with the thermal reaction condition. The average yield is moderate in a range of 30-40%. These new reactive fluorescent dyes 5-carboxy-sulforhodamines emit different color such as green, orange and red (shown below). The conjugates of these reactive dyes with streptavidin have much higher brightness than relevant conjugates of existing dyes.