Birnbaumin A and B: Two Unusual 1‐Hydroxyindole Pigments from the “Flower Pot Parasol” <i>Leucocoprinus birnbaumii</i>

Abstract

It can come as a surprise to plant lovers to find the fruit bodies of Leucocoprinus birnbaumii (see picture) in their flower pots. This fragile fungus, which is harmless to plants, owes its yellow color to the unusual alkaloids birnbaumin A and B, in which a 1-hydroxyindole-3-glyoxylic acid amide is attached through a tetramethylene unit to N-hydroxyoxamidine. N-Hydroxyoxamidines have not been described previously. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2005/z500082_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.