3-epi Ursolic acid is a pentacyclic triterpenoid that has been found in M. lingua and has diverse biological activities.1,2,3,4 It inhibits glycogen phosphorylase and cathepsin L but not cathepsin B (IC50s = 19, 6.5, and >250 ?M, respectively).1,2 3-epi Ursolic acid (20-50 ?M) inhibits entry of bovine parainfluenza virus 3 into MDBK cells.3 It also inhibits the proliferation of MCF-7 breast cancer cells (IC50 = 18.6 ?g/ml).4
1.Wen, X., Sun, H., Liu, J., et al.Naturally occurring pentacyclic triterpenes as inhibitors of glycogen phosphorylase: Synthesis, structure-activity relationships, and X-ray crystallographic studiesJ. Med. Chem.51(12)3540-3554(2008) 2.Ramalho, S.D., De Sousa, L.R.F., Nebo, L., et al.Triterpenoids as novel natural inhibitors of human cathepsin LChem. Biodivers.11(9)1354-1363(2014) 3.Pan, W., Hui, N., Wang, H., et al.Entry of bovine parainfluenza virus type 3 into MDBK cells occurs via clathrin-mediated endocytosis and macropinocytosis in a acid-dependent mannerVet. Microbiol.259109148(2021) 4.Qamar, K.A., Dar, A., Siddiqui, B.S., et al.Antiproliferative effects of Ocimum basilicum methanolic extract and fractions, aleanolic acid and 3-epi-ursolic acidCurr. Tradit. Med.6(2)134-146(2020)