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Upstream product

• 100-39-0 benzyl bromide 
• 51146-16-8 2-phenyl[1-¹⁴C]acetic acid 
• 4701-32-0 benzyl [cyano-¹⁴C] cyanide 

Relevant academic research and scientific papers

Buscopan labeled with carbon-14 and deuterium

Hyosine butyl bromide, the active ingredient in Buscopan, is an anticholinergic and antimuscarinic drug used to treat pain and discomfort caused by abdominal cramps. A straightforward synthesis of carbon-14– and deuterium-labeled Buscopan was developed using scopolamine, n-butyl-1-14C bromide, and n-butyl-2H9 bromide, respectively. In a second carbon-14 synthesis, the radioactive carbon was incorporated in the tropic acid moiety to follow its metabolism. Herein, we describe the detailed preparations of carbon-14– and deuterium-labeled Buscopan.

Stereochemistry of the 1,2-migration of the carboxyl group that occurs during the biosynthesis of tropic acid from phenylalanine

(2S,3R)- and (2S,3S)-phenylalanine were fed in separate experiments to Datura innoxia plants.The distribution of isotopes in the resultant labeled hyoscyamine and scopolamine indicates that the biosynthesis of the acid moiety of these ester alkaloids, namely (S)-tropic acid, involves the migration of the carboxyl group of phenylalanine to its prochiral C-3 position with retention of configuration.