The invention relates to a preparation method of an organic 
hybrid trinuclear 
platinum complex possessing a Y type structure synthesized by supermolecules self-
assembly as well as treatment for 
gastric adenocarcinoma cells. The MTT experiment data shows that the compound can cross a 
drug resistance mechanism of 
cisplatin, and can specifically target to the 
gastric adenocarcinoma cells. A 
platinum ligand Pt(NH3)2Cl(NO3)] in which the 
chloride ion is replaced by 
nitrate and a bridge ligand (2,4,6-tri(pyridin-4-yl)-1,3,5-
triazine) are subjected to self-
assembly, thereby the novel and latent 
medicine for treating 
gastric adenocarcinoma with excellent anticancer activity and 
tumor targeting is obtained. Because the complex enables specific recognition of the gastric 
adenocarcinoma cells, and can induce the G-rich sequence of the 
oncogene to form a G-quadruplex structure, the activity of 
telomerase can be inhibited, thereby the complex possesses high gastric 
adenocarcinoma resistance activity. The preparation method has the advantages of simple process and low cost, can be completed in a general 
chemical laboratory, and the production process is environmentally-friendly. The trinuclear 
platinum complex possessing Y type structure can be taken as the novel and latent gastric 
adenocarcinoma resistance 
medicine.