Design,Synthesis And Anti-tumor Activity Of Perillyl Alcohol Derivatives

Perillyl alcohol, a plant-derived volatile oil structurally belonging to terpenes, is one of the few agents both having preventive and therapeutic effects against a variety of tumors. This agent has a good anti-tumor effect with low toxicity and little drug resistance. However, perillyl alcohol is prone to be rapidly metabolized in vivo. Combined with the low bioavailability for oral administration, its clinical application is limited. Based on the previous study about limonene analogues in our laboratory, increasing the polarity of this compound is beneficial to improve the anti-tumor activity. In this thesis, some nitrogen-containing groups would be introduced to the structure of perillyl alcohol, aiming at yielding novel agents with excellent anti-tumor activities and little side effects.In this study, perilla aldehyde was chosen as the starting material and four skeletons were firstly synthesized, that is perillyl alcohol,7-methyl perillyl alcohol,7-ethyl perillyl alcohol and methyl perillate. Then, we designed five series of their analogues containing amino groups maintaining its molecular skeleton. Finally, sixty-one compounds were synthesized including59novel compounds. Among these derivatives,14compounds contain perillyl alcohol skeleton (A1-A14),11compounds containing7-ethyl perillyl alcohol skeleton (B1-B11),10compounds containing7-methyl perillyl alcohol skeleton (C1-C10) and18compounds containing methyl perillate skeleton (D1-D18). Besides these,8compounds were perillyl amine derivatives (E1-E8). The structures of all compounds were confirmed by MS and’H-NMR spectra.To assess the anti-proliferation effect of the61target compounds, experiments with’MTT assay’were performed in HeLa, MCF-7, HepG2, HCT116, A549, A375-S2, HT-1080, U937, HL-60and K562cancer cells,5-fluorouracil as positive control drug. The results demonstrated that the ICsos (50%inhibitive concentrations) of major compounds were lower than perillyl alcohol. This result verified that introduction of amino group to the structure of perillyl alcohol is beneficial to improve the antitumor activity.Compared with the structures and activities, preliminary structure-activity relationships (SAR) were summarized:Between perilla alcohol,7-methyl perillyl alcohol and7-ethyl perillyl alcohol derivatives (A, B, and C series), the introduction of primary amine group into the objective compound with stronger anti-tumor activity than secondary amine group; But there was no significant differences in perillic acid methyl ester derivatives (D series) with different nitrogen. Replaced Perilla alcohol structure hydroxyl group by amine (E series), the introduction of amantadine (compound E5) had stronger antitumor activity than the other compound.Investigating the potential mechanism with compound E5, the result showed that compound E5exhibited dose-dependent and time-dependent inhibition of human lung cell A549proliferation. After Measurement with phase contrast microscope, fluorescent staining and flow cytometry, the result demonstrated that compound E5could induce apoptosis of A549cell. Western blot analysis not only verified this effect but also demonstrated E5could inhibit the Raf/MEK/ERK signaling pathway of Ras downstream. Therefore, we can conclude that E5induced apoptosis of A549cell through the inhibition of farnesyl transferase resulting the inhibition of Raf/MEK/ERK signaling pathway.