Synthesis and Cytotoxic Activity of Pentacyclic Triterpenoid Sulfamates

Methyl triterpenoates derived from oleanolic, ursolic, betulinic, glycyrrhetinic, platanic, or maslinic acid were converted into their corresponding sulfamates and carbamoylsulfamates. The sulfamates were screened in photometric sulforhodamine assays for cytotoxic activity employing several human tumor cell lines. Many of the compounds showed EC 50 values in one‐digit μM concentration. Of special interest seems methyl (3β) 3‐(aminosulfonyloxy)‐11‐oxo‐oleanoate ( 18 ) showing good cytotoxicity for the human adenocarcinomic alveolar basal epithelial cell line A549 while being less toxic for non‐malignant NIH 3T3 mouse fibroblasts.