Phytochemical studies on Stemona aphylla: isolation of a new stemofoline alkaloid and six new stemofurans.
A new stemofoline alkaloid, (2'S)-hydroxy-(11S,12R)-dihydrostemofoline (3), new stemofurans M-R (8-13), and known compounds stemofoline (1), (2'S)-hydroxystemofoline (2), stemofuran E (4), stemofuran F (5), stemofuran J (6), and stilbostemin F (7) have been isolated from the root extracts of Stemona aphylla. The structures and relative configurations of these new compounds have been determined by spectroscopic data interpretation and from semisynthetic studies. These natural and semisynthetic alkaloids were tested for acetylcholinesterase inhibitory activities and were found to be 10-20 times less active than 1',2'-didehydrostemofoline itself. Stemofurans 4, 6, 8, 11, and 13 were tested for their antibacterial and antifungal activities. Three of these showed antibacterial activities against MRSA with MIC values of 15.6 μg/mL.
School of Chemistry, University of Wollongong, Wollongong, New South Wales, 2522, Australia. thanapat@uow.edu.au
Thanapat
T
Sastraruji
Sukanda
S
Chaiyong
Araya
A
Jatisatienr
Stephen G
SG
Pyne
Alison T
AT
Ung
Wilford
W
Lie
D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects; D003455:Cryptococcus neoformans / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D006576:Heterocyclic Compounds, 4 or More Rings / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D007711:Klebsiella pneumoniae / Q000187:drug effects; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D018517:Plant Roots / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects; D041901:Stemonaceae / Q000737:chemistry*; D013297:Streptococcus pyogenes / Q000187:drug effects; D013785:Thailand
D000470:Alkaloids; D000890:Anti-Infective Agents; D006576:Heterocyclic Compounds, 4 or More Rings; C481859:didehydrostemofoline; C430220:stemofoline