Design, Synthesis And Biological Evaluation Of Aminopyrimidine Derivatives As CDK4/6 Inhibitors

CDK(cycle dependence protein kinase)is an important factor in regulating the cell cycle and belong to the family of serine/threonine protein kinase.CDK and cyclin cycle protein are to form dimers,including catalytic subunit of CDK and the important factors of cycle cyclin protein the cycles.Depending on the function of CDK,it can be divided into two categories:type of CDK involved in cell cycle regulation,including CDK1,CDK2,CDK4 and CDK6,etc;The other categories of CDK involved in transcriptional regulation,including CDK7,CDK8,CDK9 and CDK10,CDK11,etc.In recent years,with Pfizer's palbociclib,novartis's ribocilib and lilly's abemaciclib successively launching,research interest for CDK was rekindled,CDK inhibitors has been more and more attention.In order to look for high activity and low toxicity of new lead compounds,this paper has listed for reference of palbociclib and ribocilib(both of CDK4/6 inhibitors)structure characteristics.In our previous research,we found two amino pyrimidine compounds A and B,using the active substructure splicing and electronic line principle method.In this paper,we designed and synthesized 72 compounds of two amino pyrimidine that did not reported in literature(series ?,? and ?),the synthesized methods of target compounds,structure characterization,preliminary study on the biological activity and structure-activity relationship are summed up.The concrete research content is summarized as follows:1.Background:the structure of CDK6,the function of CDK,the current research status of CDK inhibitors and CDK4/6 inhibitors.2.Design and synthesis of amino pyrimidine compounds:using CDK4/6 as targets.In our previous research,we determine amino pyrimidine compound A with highil antitumor activity by active substructure splicing method.Intruducing indole ring in the position of pyrimidine,we designed and sythesised series ? including total of 23 amino pyrimidine compounds containing indole rings.Using compound B as a lead,we designed and synthesised the series ? of 28 compounds by introducing palbociclib side chain.Futher optimization for series ? to form the conjugate coplanar pteridine mother nucleus of ketone structure,design and synthesis of the 21 target compounds ?.All compounds were confirmed through the nuclear magnetic resonance hydrogen spectrum(1H NMR),the nuclear magnetic resonance carbon spectroscopy(13C NMR),high resolution mass spectrometry(HRMS).3.Test of biological activity:by MTT method,we test the antiproliferative activity of target compounds in vitro in the cervical cancer cell lines(Hela),human prostate cancer cells(PC-3)and human breast cancer cell lines(MDA-MB-231),human colon cancer cell line(HT-29,HCT-116).Some highly active antitumor compounds were tested toxicity to normal human embryonic kidney(HEK293A,HEK293)cells.The results show that the activity of Series ? is not ideal,and most of the compounds for series ? and ? have a stronger inhibitory effect to the selected several kinds of tumor cells,for example:?1,?2,?11,?12,?15,?19,?23,?24,?a,?d,?e,?s,?u,especially,?11 is the same as the positive drug palbociclib about antiproliferative activity and ?s better than positive drug palbociclib,the best active compounds were futher studied by the experimental flow cytometry.The results show that ?11 and ?s significantly block Hela in G2/M phase.Tumor inhibitory activity in vitro and CDK4/6 activity of enzyme inhibition are tested,on the basis of selected active good representative compounds using palbociclib as positive control.The results show that the IC50 of CDK4/6 are 34 nM and 65nM with the same level of positive drug palbociclib,that has further research value.