The synthesis of two long-chain N-hydroxy amino coumarin compounds and their applications in the analysis of aldehydes

Abstract

Herein, two N-substituted coumaryl hydroxylamines (compounds 1a and 1b) with long aliphatic chains were prepared in 8 steps with a novel synthetic protocol. They served as derivatization agents for aldehydes by the formation of nitrones under mild conditions, which can be readily analysed by LC-MS with good chromatographic performance, excellent fluorescent response, and high ionization strength. We successfully used compounds 1a and 1b in the analysis of furfuraldehydes in raisins, based on the derivatization reactions of standard furfural (F), 5-methylfurfural (5-MF) and 5-(hydroxymethyl)furfural (5-HMF) samples. It proved that they are excellent agents for the analysis of aldehydes in foodstuffs. The derivatization reaction between compound 1a and hexanal suggested that the applications of our designed derivatization agents can be further extended to the analysis of aliphatic aldehydes. This study demonstrated that the designed N-substituted coumaryl hydroxylamines are excellent probes for the analysis of various aldehydes which are important in multiple research areas.

Chemical Transformations of Biomass-Derived C6-Furanic Platform Chemicals for Sustainable Energy Research, Materials Science, and Synthetic Building Blocks

“…Various N -nucleophiles can be subjected to reaction with HMF leading to imines, oximes, and hydrazones . Long-chain N -hydroxyaminocoumarins were used as LC-MS labels for analysis of HMF …”

“…153 Longchain N-hydroxyaminocoumarins were used as LC-MS labels for analysis of HMF. 154 HMF can be used as electrophile in the aldol reaction (Scheme 3). The obtained adducts usually act as substrates for hydrogenolysis in the synthesis of biobased fuels.…”

Progress and Challenges in Quantifying Carbonyl-Metabolomic Phenomes with LC-MS/MS

“…Although the chromatographically separated E-/Zisomers formed by the reaction of asymmetric carbonyl metabolites with O-substituted hydroxylamines have been considered useful for structure identification in some cases, it brings huge challenges to MS sensitivity. Guan et al [101] firstly designed and synthesized two novel N-substituted coumaroyl hydroxylamines (4-hydroxylaminopropyl-7-methoxylcoumarin (HAMC) and 7-hydroxy-4-(4-(hydroxyamino)butyl)-2H-chromen-2-one (HAHC)) with long aliphatic chain, which enhanced the ionization efficiency of derivatives. Compared with other O-substituted hydroxylamines, HAMC and HAHC provided a mild and efficient labeling in less than 30 min at room temperature, and also overcame the shortcomings of forming E-/Zisomers.…”