Design, Synthesis And Structure-Activity Relationships Of Coptisine Derivatives As Anti-ulcerative Colitis Agents Targeting XBP1

Ulcerative colitis (UC), a type of inflammatory bowel disease (IBD), is a recurrent and progressive inflammatory intestinal disorder, characterized by superficial mucosal lesions that extends through the rectum and progresses upstream. There is a growing body of evidence suggesting that the occurrence of UC is increasing. Depending on the degree of severity, different therapies are developed against UC, but none of them are directed at curing the disease. Instead, they focus on attenuating its symptoms. As a consequence, these treatments lead to limited remission, often with major side effects and refractory patients arising. Thus, there is an urgent need to develop effective anti-UC drugs. Recent scientific data from studies in animal models showed that the variation of the coding region and the expressive abnormalities of X-box binding protein-1 (XBP1) gene are often characteristic of UC patients. Thus, it is speculated that XBP1 may be the potential new drugs targets of treating UC. Nevertheless, there has been no claim thus far regarding the development of anti-UC drugs targeting XBP1 except for the work from our laboratory.The bioactivities of quaternary coptisine have been reported to include antidiabetic, antimicrobial, antiviral, anticancer effects and a cardioprotective function. The anti-UC activity of coptisine derivatives has also been confirmed. In order to improve the chemical stability and liposolubility of coptisine and to obtain more bioactive compounds, a series of coptisine derivatives was recently designed and synthesized in this thesis based on not only investigating references and summarise the experiences of the former work in our laboratory but also investigating systematically the chemical reactivities of the starting material coptisine.119 coptisine derivatives in ten series of different kinds of structure was design and synthesis in this paper including 8-alkylene dihydrocoptisine derivatives, N-dihydrocoptisine-8-imine derivatives,8-N,N-bis-substituted amino quaternary coptisine derivatives, 8-N, N-bis-substituted amino-13-substituted quaternary coptisine derivatives,8,8-bis-substituted dihydrocoptisine derivatives,8,8-bis-substituted tetrahydrocoptisine-7,13a-imine salt derivatives, 5,6-nordihydro-8,8-bis-substituted-13-carbonyl tetrahydrocoptisine-7,13a-imine salt derivatives, dihydrocoptisine alkyl quaternary ammonium salt derivatives,13-acyloxy-substituted coptisine quaternary ammonium salt derivatives, [1,4]dioxane[2’,3’:7,8]isoquinoline[3,2-a][1,4]dioxane[2,3-g]isoquinoline coptisine derivatives.117 coptisine derivatives of them are new structures and 2 had been published. All of the derivatives were identified by 1H NMR、13C-NMR、ESIMS, and some of them were further confirmed by NOE、IR、HRESIMS.All of the 119 compounds synthesized were evaluated bioactivities of anti-UC in vitro and some were evaluated the bioactivities in vivo. As a result, a series of compounds such as compouns 5e-1 and 10d which were new structure、targeting new site and had potential of anti-UC were discovered and then analysised of the structure-activity relationship (SAR) of them.(1) Survival rate of IEC-6 cells shows that:Except for N-dihydrocoptisine-8-ylidene aliphaticamine derivatives (the number of alkyl chain carbon atom is more than 6), 8-N, N-bis-substituted amino coptisine quaternary ammonium salt derivatives,8-N,N-bis-substituted amino-13-substituted coptisine quaternary ammonium salt derivatives and 5,6-nordihydro-8,8-bis-substituted-13-carbonyl tetrahydrocoptisine-7,13a-imine salt derivatives, the survival rate of other series of compounds is more than 70%, which made good foundation for further bioactivity evaluating.(2) The compounds did not show obvious cytotoxic on IEC-6 cells were made further XBP1 activation activity evaluation, the data of the result indicated that:some of the compounds of N-dihydrocoptisine-8-ylidene aromatic amines derivatives、N-dihydrocoptisine-8-ylidene aliphaticamides、dihydrocoptisine alkyl quaternary ammonium salt derivatives and [1,4]dioxane[2’,3’:7,8]isoquinoline[3,2-a][1,4]dioxane [2,3-g]isoquinoline dihydrocoptisine derivatives showed significant XBP1 gene transcriptional activation effect in vitro. The relative activation ratios of some compounds were from 2.11 to 3.75 times.(3) The compounds had higher XBP1 activation activity were made dose-effect relationships experiments. Some of the compounds showed good anti-UC in vitro, such as compounds 5e-1、10d、5r-2 and 21, with the EC50 values were 13.2 nM,32.5 nM, 11.4 nM and 36.3 nM, respectively.(4) Primary results of anti-UC experiments in vivo indicate that:compounds 5e-1、10d、10j、18a and 21 exhibited significant anti-UC activity. Taking body weight changes, colon contracture rates, DAI and CMDI scores, and pathological changes in the colon tissue of experimental UC animals into consideration, the compound 5e-1 exhibited better activity for UC animals than the positive control, the anti-UC drug SASP. Compounds 10d、10j、18a and 21 exhibited same anti-UC activity as SASP but less potent than compound 5e-1.Besides, the derivatives of coptisine quaternary ammonium salt were synthesized to test their cytotoxicities against several cancer cell-lines. The results shows that most of them had lower inhibited rate against HCT116、HT29、MCF7 and MDAMB231 cell lines than the positive control, the anticancer drug Paclitaxel. Few compounds can catch up with or exceed Paclitaxel. Afterwards, the dose-effect relationships were tested among the compounds of inhibited rate more than 50% and its EC50 value were calculated while evaluated their survival rate on IEC-6 cells line.As a consequence, some compounds not only showed good inhibited rate against tumor cell lines but also showed good survival rate on IEC-6 cell lines. For examples, the IC50 value of compounds 8j and 9b-1 exhibited inhibition activity on cancer cells HCT116 and HT29 were 8.89×10-6 mol/L、3.15×10-6 mol/L and 0.81 × 10-6 mol/L、 6.65 × 10-6 mol/L, respectively, while the survival percentages on IEC-6 cells were 81.3% and 92%. The study results of the thesis provide scientific basis for the innovative drug research of coptisine derivatives.