title: Squarrosine A and Pyrrolhuperzine A, New Lycopodium Alkaloids from Thai and Philippine Huperzia squarrosa.
abstract: Two new Lycopodium alkaloids, squarrosine A (1) and pyrrolhuperzine A (2), were isolated from the Thai and Philippine plant Huperzia squarrosa. (R)-2-Piperidineacetic acid (5) was a known alkaloid, but has now been isolated for the first time from a natural source. Their structures were elucidated using extensive spectroscopic analyses and, for pyrrolhuperzine A (2), confirmation by chemical transformation. The new compounds exhibited moderate acetylcholinesterase inhibitory activities.
authors.affiliation: Applied Biological Sciences Program, Chulabhorn Graduate Institute, Bangkok, Thailand.
authors.forename: Thanasan
authors.initials: T
authors.lastname: Nilsu
authors.affiliation: Laboratory of Medicinal Chemistry, Chulabhorn Research Institute, Bangkok, Thailand.
authors.forename: Sakornrat
authors.initials: S
authors.lastname: Thorroad
authors.affiliation: Laboratory of Medicinal Chemistry, Chulabhorn Research Institute, Bangkok, Thailand.
authors.forename: Somsak
authors.initials: S
authors.lastname: Ruchirawat
authors.affiliation: Laboratory of Medicinal Chemistry, Chulabhorn Research Institute, Bangkok, Thailand.
authors.forename: Nopporn
authors.initials: N
authors.lastname: Thasana
mesh_terms: D000110:Acetylcholinesterase; D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002800:Cholinesterase Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006575:Heterocyclic Compounds, 3-Ring / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006576:Heterocyclic Compounds, 4 or More Rings / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D032501:Huperzia / Q000737:chemistry*; D015394:Molecular Structure; D010679:Philippines; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013785:Thailand
chemical_list: D000470:Alkaloids; D002800:Cholinesterase Inhibitors; D006575:Heterocyclic Compounds, 3-Ring; D006576:Heterocyclic Compounds, 4 or More Rings; D010936:Plant Extracts; C000614936:pyrrolhuperzine A; C000614935:squarrosine A; D000110:Acetylcholinesterase