Design,Synthesis,and Anti-Tumor Activity Study Of Pyridino[2,3-d]Pyrimidine Compounds And Lapatinib Derivatives

In the past half-century, so much progress has been made in the studies on cancer treatment. With the deepening study on cancer genomics and biology, several key intracellular cancer-related signaling pathways have been discovered. Tumor cells depend on these pathways to achieve intracellular transduction of extracellular signal, regulating their continued proliferation, invasion and metastasis and anti-apoptotic activity to maintain their malignant phenotypes and on the other hand to cause resistance to the treatment through regulating certain genes and protein products. One of the main pathways is the PI3K/AKT/ mTOR pathway that has become the preferred target for anti-cancer drug development.In order to obtain more effective m-TOR/PI3K inhibitor, we made further structure-activity studies on the series of molecules which possess a pyridino[2,3-d] pyrimidine scaffold, referring to the existing data of the structure-activity relationship. We focused on the optimization of C2 substituents on the right side of the scaffold, and studied the structure-activity relationships of these molecules by using multiple series of substituents including tetrahydropyrane amino substituents, tetrahydropyrane ring substituents, piperidine-4-amino substituents, N-methyl-piperidine-4-amino substituents, seven amide ring substituents, five-membered ring substituents and small group substituents. Meanwhile, C4 substituent on the top of the scaffold was replaced with 3 (S)-methyl morpholine, morpholine and 8-oxa-3-azabicyclo [3.2.1] octane-3-yl, respectively. Furthermore, according to the literature, C7 position of the benzene ring on the left side of the scaffold was replaced with multiple substituents such as 3-hydroxymethyl-4-methoxy,3-hydroxymethyl-4-difluoro methoxy,3-hydroxymethyl-4-fluoride,4-hydroxyl tetrahydropyrano ring and 3-carbamoyl, with aim to find molecules which have excellent activity both in vitro and in vivo. Through numerous experiments, on the molecule level, there are 34 designed compounds whose IC50 values toward mTOR are less than 100 nM. Among them,9 of these compounds have their IC50 values less than 5 nM, compound 49 has the strongest activity (ICso=0.4 nM). In addition, 13 compounds toward p110-a subunit in PI3K possess IC50 values less than 1 μM, and 7 of these compounds have IC50 data less than 300 nM. Among these compounds, compound 8 has the most potent activity (IC50=13 nM). On the cell level, there are 40 compounds for which the IC50 values toward CMF-7 cell are less than 1 uM. Among them, the IC50 data for 9 of these compounds are less than 50 nM, and compound 4 has the lowest value with ICso=2.1 nM. It is noted that there are 31 compounds for which the IC50 toward PC-3 cell is less than luM, and 4 of these compounds have IC50 values less than 100 nm, compound 31 is found to have the best activity (IC50=26 nM).Breast cancer is the most common malignant tumor in humans and is also one of the main malignant tumors in female. The incidence of breast cancer accounts for 7-10% of all the human malignant tumors. According to the World Health Organization, about 1.2 million women were diagnosed with breast cancer worldwide every year, and the incidence is rising at a rate of 5%-20% a year. The morbidity is always associated with heredity. The incidence is relatively high in postmenopausal and premenopausal women and in those aged 40 to 60. Only about 1-2% of the breast cancer patients are male. Breast cancer usually occurs in breast glandular tissue and is one of the most common malignant tumors which can seriously impact on women’s physical and mental health and can even be life-threatening.Lapatinib (GW-2016) is a reversible tyrosine kinase inhibitor. It possesses a unique advantage that it inhibits both EGFR and HER2, thus it is a dual-target growth factor receptor tyrosine kinase inhibitor. To obtain an active and good candidate compound for the subsequent pre-clinical research, we firstly designed and developed, in this thesis, a set of new compounds focused on the modification of Lapatinib’s cationic Center (PI)-moving the chain amino outside the chain, which ensured the identical efficacy to that of Lapatinib. Through the in vitro activity evaluation, HER-003 was obtained as a lead compound. We further improved the structure of HER-003 by introducing one methyl group to the free amino group (HER-014), two methyl groups to the free amino group (HER-020) and other common groups to the free amino group. HER-020 was found to have obvious advantages in stability and pharmaceutical properties. Since the chain amino group was moved outside the chain, there were two chiral isomers. Further research showed that the laevo isomer and its dextro isomer have almost the same bioactivity. With the consideration of the availability of the chiral reagent (R)-N-tert-butanesulfinyl imines, the laevo isomer of HER-020, HER-036, was chosen as the drug candidate molecule in the further development and was named as xipatinib tosilate.Through the subsequent bioactivity test, xipatinib is a superior dual-target tyrosine kinase inhibitor, whose activity is equal to or even better than lapatinib both in vivo and in vitro tests. It also showed good pharmacokinetic properties in pharmacokinetic studies.