Synthesis of Conjugates of Lupane-Type Pentacyclic Triterpenoids with 2-Aminoethane- and N -Methyl-2-Aminoethanesulfonic Acids. Assessment of in vitro Toxicity

Conjugates of betulin and betulinic and betulonic acids with 2-aminoethane- and N-methyl-2-aminoethanesulfonic acids were synthesized for the first time and were interesting as potential biologically active compounds. Experiments in vitro in MDCK cell culture using the MTT assay found that betulin and betulinic-acid derivatives with aminoethanesulfonic acid bound to triterpene C-3 or C-28 through an ester linker were less toxic than the native compounds.