ISSN:
0075-4617
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Components of the Green Deathcap Toadstool Amanita phalloides, LV. Peptide Syntheses, LXII. Isolation, Characterization and Total Synthesis of Prophalloin (Pro4-phalloin), a Non-toxic Probable Precursor of the PhallotoxinsThis report describes the isolation, characterization, and total synthesis of a new member of the phalloidin family, which occurs in minimal amounts in the methanolic extract of Amanita phalloides: prophalloin (1d) a non-toxic component contains proline instead of allo-hydroxyproline in position 4 of phalloin (1a). Coupling of the S-chloride of Boc-alanyl-D-threonyl-cysteinyl-proline (5) with alanyl-tryptophyl-γ-hydroxyleucine-lactone yields the thioether 6, which on cyclization yields Boc-secoprophalloin-lactone 7. Removal of the Boc-group, opening of the lactone ring, and a second cyclization leads to prophalloin (1d) which is identical with the natural product according to its biological and spectroscopic properties.
Notes:
Es wird über Isolierung, Charakterisierung und Totalsynthese eines in geringer Menge im Methanolextrakt von Amanita phalloides enthaltenen Vertreters der Phalloidinfamilie berichtet: Prophalloin (1d), eine ungiftige Komponente, enthält anstelle des allo-Hydroxyprolins von Phalloin (1a) in 4-Stellung Prolin. Die Kopplung des S-Chlorids von Boc-Alanyl-D-threonyl-cysteinylprolin (5) mit Alanyl-tryptophyl-γ-hydroxyleucinlacton liefert den Thioether 6, dessen Cyclisierung Boc-geschütztes Secoprophalloinlacton 7 ergibt. Boc-Abspaltung, Öffnung des Lactonrings und zweite Cyclisierung führten zu Prophalloin (1d), das in seinen biologischen und spektroskopischen Eigenschaften mit dem Naturstoff identisch ist.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.197819780511
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