Four new triterpenoid glycosides were isolated from the root bark of Mussaenda macrophylla. Their structures were determined as 3-O-β-D-glucopyranosyl-28-O-α-L-rhamnopyranosyl-16α-hydroxy-23-deoxyprotobassic acid (1), 28-O-β-D-glucopyranosyl-16α-hydroxy-23-deoxyprotobassic acid (2), 3-O-β-D-glucopyranosyl-28-O-α-L-rhamnopyranosyl-16α-hydroxyprotobassic acid (3), and 3-O-{[β-D-glucopyranosyl(1→6)-O-α-L-rhamnopyranosyl(1→2)-O-β-D-glucopyranosyl-(1→2)}-O-β-D-glucopyranosyl-(1→3)-O-β-D-glucopyranosyl-cycloarta-22,24-dien-27-oic acid (mussaendoside W, 4). Four known triterpenoids [3-O-acetyloleanolic acid (5), 3-O-acetyldaturadiol (6), rotundic acid (7), and 16α-hydroxyprotobassic acid (8)] were also isolated. The structures of 1-4 were determined by several spectroscopic techniques including 2D NMR methods. Compounds 1-6 showed inhibitory activity against a periodontopathic bacterium, Porphyromonas gingivalis, but were inactive against the cariogenic organism, Streptococcus mutans.
antimicrobial activity, triterpenoid glycoside, Mussaenda macrophylla
NCBI PubMed ID: 10543897Publication DOI: 10.1021/np9901579Journal NLM ID: 7906882Publisher: American Society of Pharmacognosy
Correspondence: Kinghorn AD
Institutions: Program for Collaborative Research in the Pharmaceutical Sciences and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, USA, Mycotoxin Research, National Center for Agricultural Utilization Research, USDA, ARS, Peoria, Illinois 61604, USA, Department of Periodontics, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois 60612, USA
Methods: 13C NMR, 1H NMR, IR, FAB-MS, TLC, ESI-MS, GC, HPLC, UV, ROESY, TOCSY, HMBC, antimicrobial assay, HCl hydrolysis, trimethylsilylation, oprical rotation measurement
Found