Synthesis of Six Phenylalanine Derivatives and their Cell Toxicity Effect on Human Colon Cancer Cell Line HT-29

Some phenylalanine (Phe) derivatives had important roles in pharmacology and may be used as pharmaceutical materials and pharmaceutical intermediates. In order to understand the cell toxicity of phenylalanine derivatives, we synthesized L-4-bromo-phenylalanine (Brp), L-4-iodophenylalanine (Ip), L-4-nitro-phenylalanine (Np), L-4-sulfonic-phenylalanine (Sp), L-4-phosphophenylalanine (Pp) and L-4-amino-phenylalanine (Np). We used mass spectrometry (MS), Infrared Spectroscopy (IR) or hydrogen-1 nuclear magnetic resonance spectrum (1H-NMR), and high performance liquid chromatography (HPLC) to test the correction of these products, MTT assay and Hoechst33258 staining to detect their cell toxic effect on human colon cancer cell HT-29 (HT-29 cells). The results showed that these products were correct and the cytotoxicity of PpIpSp and NpBrp, Ap almost had no effect on HT-29 cells. In addition, Pp, Ip and Sp induced cell apoptosis, the other three kinds of phenylalanine derivatives induced neither apoptosis nor necrosis. Keywords: Phenylalanine, L-4-phenylalanine derivatives, human colon cancer cell line HT-29 (HT-29 cells), median lethal dose (LD50), cell toxicity, cell apoptosis.