The β-carboline alkaloids have been characterized as a class of potential antitumor agents. To further enhance the cytotoxic potency and improve water solubility of β-carboline, a series of new β-carboline amino acid ester, β-carboline amino acid and N2-benzylated quaternary β-carboline amino acid ester conjugates were designed and synthesized, and the cytotoxic activities of these compounds were evaluated using a panel of human tumor ...
