• Proceedings of the PSK Conference
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• 2002.10a
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• pp.348.3-349
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• 2002

(－)-${\alpha}$-narcotine( 1 R.9S) is one of the major bases in Papaver somniferum L.. the sourse plant for opium. while (－)-${\beta}$-narcotine(1R.9R) is a synthetic phthalideisoquinoline alkaloid. Although some advanced methods for the preparation of $\alpha$-narcotine have been developed using modified Bischler-Napieralski cyclization. the facile synthesis of $\beta$-narcotine has not further been attempted. supposingly because of its no clinical efficacy contrary to $\alpha$-narcotine having an antitussive effect. (omitted)

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.147-151
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• 2005

A$(-)-\alpha$-narcotine from Papaver sommiferum was refluxed with ethyl chloroformate to give the diastereomeric chloro-carbamate mixture and the Z/E-enol lactones as Z:E=1:1.1 ratio in HPLC analysis. After photoisomerization with UV (254 nm), the Z/E ratio was drastically changed to Z:E=7:1, which may indicate that the E-isomer was easily converted to the Z-isomer due to photoisomerization. The photoisomerization of the Z/E-enol lactones and the different stereochemistry of the degradation product of $\beta-narcotine$, deuterated $\beta-narcotine$ and $\beta-narcotine$ with ethyl chloroformate will also be discussed.

• Bulletin of the Korean Chemical Society
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• v.23 no.11
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• pp.1548-1552
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• 2002

$(-)-\beta-Narcotine$ (6), a phthalideisoquinoline alkaloid, was synthesized conveniently by the direct condensation of cotarnine (1) and iodomeconine (2) prepared by aromatic iodination using thallium trifluoroacetate/KI and by the successive reduction of resulting $iodo-{\beta}-narcotine$ (5) with aluminum amalgam. Its structure including a stereochemistry was confirmed by instrumental analyses. This synthetic alkaloid was degraded with ethyl chloroformate at room temperature to afford the chloro-carbamate 6b as a crystalline intermediate, which was unexpectedly converted into the carbinol 8 by exchange of Cl with OH of water contained in the solvents and the ethoxy-carbamate 9, probably because of ethanol added to chloroform as a solvent stabilizer during the purification by column chromatography.