Study On Synthesis Optical Properties Of Nitro Or Chloricsubstitutional Blebbistatin Compounds

In the fields of fine chemicals, such as pesticide, medicine, dyestuff, heterocyclic compound containing nitrogen play an important role, and have been the focus of the research for many years. Small organic molecules that target specific proteins and act as either agonists or antagonists of particular cellular processes have played a major role in cell biological research. High-throughput screening of small molecules is extensively used to find the molecules that can effectively interact with target proteins. But only a small percentage of the small molecules identified in these screens have been studied in sufficient detail to explain the molecular basis of their effect.Blebbistatin (1-phenyl-1,2,3,4-tetrahydro-4-hydroxypyrrolo[2,3-b]-7-methylquinolin-4 -one) was recently identified as a selective, cell-permeant inhibitor of myosin II. The levo-rotatory form of blebbistatin is identified as an inhibitor which can inhibit the ATPase activity of skeletal muscle myosin II and non-muscle myosin IIA and IIB from platelets at micromolar levels, but can not inhibit that of myosin I, V or X. It can also inhibit the ability of skeletal-muscle and non-muscle myosin II to move actin filaments in an in vitro motility assay. Furthermore, because blebbistatin readily crosses cell membranes, it can inhibit myosin II-dependent processes in situ, and has been shown to inhibit cytokinesis of HeLa cells, matrix contraction by dermal fibroblasts, and migration of pancreatic adenocarcinoma cells. Its selectivity and cell permeability make blebbistatin a valuable tool for studying the elusive function of myosin II in non-muscle cells, particularly the role of myosin II in the molecular mechanics of cell movement. Blebbistatin acts as an uncompetitive inhibitor by binding to the ADP-Pi complex at the myosin head and inhibiting Pi release.However, in the presence of blebbistatin, myosin II activity is acutely sensitive to 488 nm light. Illumination of blebbistatin-treated cells at 450–490 nm cause dose-dependent cell death, change its absorption and emission spectra, but the resultant compounds are not toxic. However, a blebbistatin analogue containing a nitro functionality resulted in improved optical properties.In this paper, we use 2-amino-5-nitro benzoic acid or 4-chloric benzoic acid and 1-phenyl-2-pyrrolidinone as initial material, two new blebbistatin compounds, 3a-hydroxy-6-nitro-1-phenyl-1, 2, 3, 3a-tetrahydro-pyrrolo[2, 3-b]quinolin-4-one and 3a-hydroxy-7-chloric-1-phenyl-1,2,3,3a-tetrahydro-pyrrolo[2,3-b]quinolin-4-one,were synthesized through four steps, including esterification, imine synthesis, cyclization and asymmetric synthesis.Their structures were confirmed by IR, ~1H NMR techniques and elemental analysis. The single crystals of some important intermediates were determined. The experimental methods were discussed in detail, parts of the experiment were improved, post-processing operations were simplified, the yield of the target compounds was improved, synthetic conditions, spectral properties of the target compounds were analyzed and discussed systemly. Their optical properties were preliminarily studied, and we discovered that under the same concentration, the UV-vis absorption and fluorescence emission intensities of the new compounds were higher than the compounds of reported previously.