Synthesis of polycarpine, a cytotoxic sulfur-containing alkaloid from the ascidian Polycarpa Aurata, and related compounds

Article abstract of DOI:10.1016/S0040-4039(97)00668-0

Polycarpine 1, a highly cytotoxic marine natural product, has been synthesized in three steps from p-methoxyphenacyl bromide 4 in 57% overall yield. The key reaction for construction of the symmetrically substituted disulfide linkage of polycarpine is the treatment of 2-amino-4-(4-methoxyphenyl)-1-methylimidazole 17 with S₂Cl₂ in acetic acid. In a similar way ten related compounds, including three thiazole analogues, have been prepared. Most of them exhibit high cytotoxic activities against an array of human cancer cell lines.