New Indole Synthesis And Properties Of The Calcium Fluorescent Indicator

As an essential elemental composition in humans, calcium constitutes bones and maintains biological forms. Moreover, Ca2+ plays a critical role in regulation of neural activity, solidification of blood, shrink and relaxation of muscle and vessel, transfer of biological signal. Calcium is an inevitable element in humans, and it means a lot in living bodies.Since 1980s, Tsien and his colleagues have developed a series of fluorescence Ca2+ indicators based on EGTA and chelator BAPTA, called the first generation of fluorescence Ca2+ indicators, which is of tremendous applications to measure the concentration of Ca2+ Under the hard work of scientists, the third generation of Ca2+ indicators has been developed, most of them are based on the structure of BAPTA. This kind of indicators has quick response and high affinity to Ca2+, which can accurately and timely indicate the distribution and change of [Ca2+] in living cells. As a result, on the one hand, fluorescence Ca2+ indicators are predominantly used in the fields such as biology and clinical medicine, on the other hand, the design and synthesis are the hot issues in organic chemistry. Widely-uesd Ca2+ indicators can be divided into two groups:one can be stimulated by visible light, represented by fluo-3; the other one can be stimulated by UV light, represented by Indo-1. Indo-1 has several advantages, such as:(1) a ratiometric indicator; (2) greater selectivity for Ca+ over other divalent metal ion such as Mg2+, Mn2+, and Zn2+; and (3) increased fluorescence quantum efficiency. However, as an indicator stimulated by UV light, there are still a few shortcomings.In order to change the excitation wavelength of indo-Ca+ indicators and transfer it closer to the region of visible light. We provide a solution based on the comparative study on the structures of BAPTA and Indo-fluorescence Ca2+ indicators. In this thesis, the investigations about design and synthesis of fluorescence Ca2+ indicators include the following several aspects:1. Under the analysis on BAPTA structure, two novel indicators were designed and synthesized, with their structures clarified. 2. Two unreported, novel Indo- fluorescence Ca2+ indicators' methyl esters were designed and synthesized, with the methyl ester structures clarified. Meanwhile, the synthetic methods were discussed and the experimental conditions were improved.3. The spectra of the one novel Indo- fluorescence Ca2+ indicator was studied and compared with Indo- fluorescence Ca2+ indicators used now, the results indicate a red shift in excitation wavelength.