Synthesis and antiviral activities of spacer-linked 1-thioglucuronide analogues of glycyrrhizin

• Christian Stanetty,
• Andrea Wolkerstorfer,
• Hassan Amer,
• Andreas Hofinger,
• Ulrich Jordis,
• Dirk Claßen-Houben and
• Paul Kosma

Beilstein J. Org. Chem. 2012, 8, 705–711, doi:10.3762/bjoc.8.79

• . The deprotected compounds containing these carboxylic acid appendices mimic the glycon part of glycyrrhizin as well as the hemisuccinate derivative of glycyrrhetinic acid, carbenoxolone. Antiviral activities of the compounds were determined in a biological test based on influenza A virus-infected

• cells, wherein the 3-(2-thioethyl)-N-acetylamino- and 3-(2-thioethyl)-thio-linked glucuronide derivatives were effective inhibitors with IC50 values as low as 54 µM. Keywords: antiviral activity; carbenoxolone; glycyrrhizin; influenza A virus; thioglycoside; triterpene; Introduction The triterpene

• acid function present in the glucopyranosiduronic residues of the parent compound glycyrrhizin (GL) and in the hemisuccinate moiety of the glycyrrhetinic acid derivative carbenoxolone (CBX) [15] (Figure 1). For the sake of clarity, the nomenclature and numbering for the triterpene system as used