Design, Synthesis And Activity Evaluation Of Novel Protein Tyrosine Kinase Inhibitors Containing Sulfone And Sulfoxide Structures

Objective:With the antitumor effects of tyrosine kinase inhibitors being recognized, protein tyrosine kinase has became an important target for modern cancer treatment. Studies found that the anti-radiation drug Ex-Rad has certain tyrosine kinase inhibitory activity. In this study, we use Ex-Rad as the lead compound, design and synthesize new compounds containing sulfone and sulfoxide structures. A preliminary evaluation of its inhibitory activities was done to screen new tyrosine kinase inhibitors with PTK inhibitory activities and certain intellectual property.Methods:1. We design compounds by checking literatures, using the bioisosterism of medicinal chemistry and the basic laws of effective active structures, and reasonably changing part fragments. 2. Chloro(bromo) benzyl with different substituents were the starting materials, and conducted nucleophilic substitutions with thioglycolic acid, then oxidated by 30% hydrogen peroxide at different temperatures and durations to give sulfone and sulfoxide respectively. The products of the previous steps were reacted with substituted salicylaldehyde and the 1st class target compounds were given after column chromatography or recrystallization. The starting materials o-hydroxyphenylacetic acid / 5-fluoro-2-hydroxyphenyl acetic acid were respectively condensated with carbazate ethyl ester, and formed a ring under the action of thionyl chloride, then reacted with substituted chloro(bromo) benzyl to form sulfides. The sulfides were oxidated by diferrent amounts of hydrogen peroxide and at different temperatures, the raw products were isolated and purified to give the 2nd class target compounds containing sulfone and sulfoxide structures. 3. To measure the inhibitory activities, we use the methord of enzyme-linked immunosorbent. Experiments were divided into five groups of blank control, negative control, positive control, vehicle control and target drugs. Ex-Rad is the positive drug, andDMSO is the solvent. Kinase reaction was done under 37 oC, and incubated for 30 minutes. The protein concentration of extract is 11.2 mg·m L-1, and diluted to 50 μg·m L-1, and used an amount of 50 μl. The labeled monoclonal antibody is diluted by 2000. At concentrations of 100 μmol·L-1 and 1 mmol·L-1, an initial tyrosine kinase activity screen of the target compounds was conducted and compared with the positive drug. Finnaly the QSAR was analyzed.Results:1. This study designed and synthesized two types of five groups of compounds: WT group(36), N group(30), BR group(29), FN group(22) and TF group(22), a total of 139 target compounds, including two known compounds, 137 new compounds and synthesized a lot of important intermediates, corresponding physical and chemical properties were obtained, and their structures were confirmed by 1H-NMR. 2. The activity evaluation results showed that at the concentrations of 100 μmol·L-1 and 1 mmol·L-1, the majority of the target compounds had inhibitory activities of tyrosine kinase. In compounds of the first class, WT002~WT004, WT007, WT009, WT011, WT014, WT018, WT019, WT021, WT029, WT034, N005, N009~N012, N014~N020, N025~N032, BR01, BR02, BR08~BR10, BR24 had higher inhibitory activities than the positive drug Ex-Rad at both concentrations, showing strong activities. In the second class, a total of 18 compounds had higher inhibitory activities than the positive drug at the concentration of 100 μmol·L-1, while at the concentration of 1 mmol·L-1, only FN06 had an equal inhibition rate with Ex-Rad considerably.Conclusion:This study designed and synthesized 139 target compounds, including 137 new compounds, most of the target compounds had stronger inhibitory activities than the positive drug Ex-Rad, showing good inhibition of tyrosine kinase activity, and acquired the desired purposes. All of these will lay solid foundation for the future related researches and studies on anti-radiation drugs.