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Updated: Mar 21, 2026

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Synthesis of Chiral Bicyclic Guanidinium Salts using Di(imidazole-1-yl)methanimine
Aleksej Turočkin1, Roman Honeker1, William Raven1
1Institute of Organic Chemistry and ‡Institute of Inorganic Chemistry, RWTH Aachen University , Landoltweg 1, 52074 Aachen, Germany.
Abstract:
A detailed account of the synthesis of chiral bicyclic guanidinium salts is presented. This work represents the first systematic investigation of an approach toward the challenging target molecules via a key guanylation step employing di(imidazole-1-yl)methanimine (6) followed by a two-fold cyclization, which resulted in guanidinium salts 8 and 10. Factors governing the regioselectivity of the final cyclization step are discussed based on further data obtained in the course of the attempted syntheses of two additional bicyclic guanidinium salts.
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