The quaternary alkaloids of Aspidsoperma peroba F. Allem. ex Sal

Qaisuddin, Muhammad (1964) The quaternary alkaloids of Aspidsoperma peroba F. Allem. ex Sal. PhD thesis, University of Glasgow.

Abstract

Recently, much interest has been shown in the tertiary alkaloids obtained from many species, of Aspidosperma (Apocynaceae) but comaratively few reports have appeared on the quaternary alkaloids of this genus, a neglect possibly due to the greater difficulty of isolating water-soluble bases from natural mixtures. The present work gives a review of known Aspidosperma alkaloids and reports on the partial separation of quaternary alkaloids from an extract of the stem bark of Aspidosperma peroba F. Allen ex Sald. (=A. polyneuron M. Arg.) The miixture was shown by paper chromatography and thin-layer chromatoraphy to contain it least five alkaloids. The alkaloid limousine B, previously reported in Struchnos toxifera (Loganiaceae) was isolatled as the thlooyanate and converted to the known Corresponding tertiary alkaloid normacusine 13. Both compounds were (ihitractorised by physical data, infrared and ultraviolet spectra, and preparation of derivatives. From the mixed thiocyanate which had yielded rmcusine Bs a methanolsolublo fraction gave a second quaternary compound which was isolated as the iodide for which m.p., ultraviolet and- infrared spectra, and optical rotation are quoted. Attcrapts were matte to separate the reaaining alkaloids, precipitated as reinockates and converted to chlorides, by adsorption 2, chromatograpity on alumina followed by counter-current distribution oi by partition chromatography using a range of conditions and many solvent systems. In particular, certain fractions from the amina columns were subjected to distribution on a ateacli.atate machine (by courtesy of Messrs, Quickfit and Quartz Ltd.) and preparative separations were also attempted Using. paper chromatography on large paper rolls in a Ohromax pressure mantis, No satisfactory separation of the quaternary chlorides was o achieved; therefore a miztnre containing three of the compounds was treated with ethanolerine to convert them to tertiary bass. From the reaction mixture one crystoilline compound was isolated but this proved to be an ethanolamide. This compound was treated with methanolie hydrochloric acid to give the corresponding methyl ester and then this tertiary base converted to its methochloride using methyl chloride. Information is given on the ethanolonide and the tertiary base which are sham to be typical 23 disubstituted indoles. Nacusine B nitrate has been shown to exhibit very feeble neuromuscular blocking activity as measured on the isolated frog rectus abdominie preparation.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: F Fish
• Keywords: Organic chemistry, Pharmacology
• Date of Award: 1964
• Depositing User: Enlighten Team
• Unique ID: glathesis:1964-74168
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 23 Sep 2019 15:33
• Last Modified: 23 Sep 2019 15:33
• URI: https://theses.gla.ac.uk/id/eprint/74168