A Neglected Challenge in the Analysis of Active Pharmaceutical Substances with Aldehyde Functional Group in Aqueous Matrices

Abstract

: Aldehydes are compounds that are widely used and popular in organic synthesis due to their high reactivity. This advantage is a disadvantage in medicinal chemistry. Due to the ability of aldehydes to participate in nucleophilic reactions (especially in aqueous biological media) and access to nucleophiles such as amino acids and nucleic acids, drugs with aldehyde functional groups are always used with caution and carefully quantified in biological fluids. Our experience in working on biologically active aldehydes indicates the transformation of these groups of compounds in aqueous or alcoholic solution and thus the failure of analytical methods for their accurate monitoring in such media. Both mass spectrometry and Proton nuclear magnetic resonance spectroscopic findings indicate the reaction of spiramycin with water molecules in an aqueous solution, resulting in the conversion of spiramycin to a new molecule with 18 mass unit difference and thus, the residue amount which is measured and reported based on a mass spectrometries method does not show the correct amount of spiramycin in these samples.

Can a gem-Diol Moiety Be Isolated? A Reaction Study by NMR and X-ray Spectroscopies

“…In this sense, instructors presented the case of spiramycin, whose structure contains an aldehyde that hinders the accurate quantification of biologically active compounds in aqueous and ethanolic solutions. In general, if the presence of the gem -diol moiety is not considered, the aldehyde residue that is measured and reported does not reflect the correct amount of active spiramycin in the samples …”

“…In general, if the presence of the gemdiol moiety is not considered, the aldehyde residue that is measured and reported does not reflect the correct amount of active spiramycin in the samples. 23…”