Mosher's Amide-Based Assignment of the Absolute Configuration of Phantasmidine
摘要:
The absolute configuration of phantasmidine was assigned by analysis of the two conformers of the two Mosher amides. The expected shielding of the protons adjacent to the nitrogen and large long range shielding (similar to 1 ppm) of the cyclobutane methylene protons in 16major and the pyridine protons of 16minor by the phenyl group of the Mosher amide allows the assignment of absolute configuration as shown in Schemes 4 and 5.
Phantasmidine: An Epibatidine Congener from the Ecuadorian Poison Frog <i>Epipedobates anthonyi</i>
作者:Richard W. Fitch、Thomas F. Spande、H. Martin Garraffo、Herman J. C. Yeh、John W. Daly
DOI:10.1021/np900727e
日期:2010.3.26
The skin of the Ecuadorian poisonfrog Epipedobates anthonyi contains the potent nicotinic agonists epibatidine (1) and N-methylepibatidine (3). In addition, a condensed tetracyclic epibatidine congener has been identified with activity at nicotinic acetylcholine receptors, but different selectivity than epibatidine. This rigid tetracycle has been named phantasmidine (4). Phantasmidine has a molecular
Reaction of 6-chloro-2-fluoro-3-pyridineacetamide with 1,2-bis(trimethylsilyloxy)cyclobutene in ether saturated with hydrogen chloride afforded the keto amide in 85% yield. In the key step, treatment of the keto amide with aqueous KOH in t-BuOH resulted In a tandem intramolecular aldol reaction-intramolecular nucleophilic aromatic substitution sequence to give the tetracylic lactam In 46% yield. Reduction of the lactam with BH3 In THF gave phantasmidine in 67% yield.
NICOTINIC ACETYLCHOLINE RECEPTOR AGONISTS
申请人:Daly Kathryn
公开号:US20130281482A1
公开(公告)日:2013-10-24
The invention provides novel nicotinic acetylcholine receptor agonists, for example, phantasmidine and derivatives thereof, for example a compound of formula (I). Also disclosed are methods of treating disorders responsive to nicotinic acetylcholine receptor agonists such as Alzheimer's disease, schizophrenia, Myasthenia Gravis, Tourette's syndrome, Parkinson's disease, epilepsy, pain, and cognitive dysfunction by treatment with the nicotinic acetylcholine for agonists.