Synthesis and cytotoxicity of pentacyclic triterpenes‐aniline nitrogen mustard derivatives

To discover novel nitrogen mustards, the reported mustard pharmacophore was combined with natural pentacyclic triterpenes, which are characterized with pharmacological and structural diversity. Thus, six conjugates were synthesized with 1,2,3-triazole linking N,N-bis (2-chloroethyl)-1,4-phenylenediamine and oleanolic acid, ursolic acid, or glycyrrhetinic acid, and their biological activity was evaluated against tumor cell lines HeLa, BGC-823, BEL-7404, and NCI-H460 using the MTT assay. As a result, these conjugates showed some selective cytotoxicity to NCI-H460, though all their activity potency was moderate or weak in the four cell lines.