Comprehensive Characterisation of n‐Alkylresorcinols and Other Lipid Constituents of Mercurialis tomentosa L. from Alicante, Spain

Abstract

Mercurialis tomentosa L. has been used in Spanish ethnomedicine. In the present study the first phytochemical characterisation of a lipid fraction from M. tomentosa was performed. The CHCl extraction of aerial parts from M. tomentosa and GC/MS investigations revealed the occurrence of cuticular lipid and wax constituents, like long chain n-alcohols and n-aldehydes (C - C ), besides several aromatic constituents, i.e., phenylpropanoids and n-alkylresorcinols. The latter were further purified by CC and analysed by LC/MS . In contrast to other Mercurialis species, i.e., M. annua, M. perennis, which exclusively contain 5-n-alkylresorcinols (1a - j, C ), mainly 5-n-alkyl-2-methylresorcinols (2a - j, C *) with side chain lengths of C - C were found in M. tomentosa, in addition to 1a - j. Thus, the latter compounds may be utilised for analytical characterisation and authentication of M. tomentosa based on fingerprinting methods. For structure elucidation a novel facile total synthesis of one representative 5-n-alkyl-2-methylresorcinol homologue (2d, C *) was developed, starting with a Grignard reaction from a substituted benzoic acid chloride (19). The compound obtained by synthesis was identical to the natural product 2d in terms of its chromatographic and spectroscopic features. Futhermore, 2d exhibited satisfactory DPPH free radical scavenging activity (IC = 37.8 μm) when compared to trolox (IC = 21.0 μm), corroborating the antioxidant features of these amphipathic molecules.

Bioactive Phytochemicals from Mercurialis spp. Used in Traditional Spanish Medicine

“…Several studies have been published on the chemical composition of M. annua [15,43,78], M. perennis [5,10,12,14,15,16,79,80], and M. tomentosa [19], confirming the presence of a wide variety of phytochemicals in these species (Table S1). Some of them possess some interesting biological activity, which has already been extensively validated scientifically (Table 2).…”

“…are presented in Figure 2. They are flavonoids, coumarins, alkaloids, phenolic acids, terpenes and steroids, and miscellaneous compounds, such as simple aromatic constituents and phenolic lipids [5,14,15,19,43].…”

“…Several studies characterizing the chemical composition of Mercurialis spp. have already been published [5,10,11,12,13,14,15,16,17,18,19]. Here, we reviewed the chemical composition of the four aforementioned species in order to elucidate which phytochemicals could be the basis of the claimed therapeutic activity of Mercurialis in Spanish folklore.…”

White Birch Trunk Extracts as a Source of Organic Compounds

“…Moreover, an analysis of 3,4‐dihydroxybenzoic acid methyl ester ( b23 ), as the trimethylsilyl derivative by GC/MS is known in the literature, was performed . 2‐(4‐Hydroxyphenyl)propane‐1,3‐diol ( b28 ) is well‐known in the literature as a synthetic product …”

Conversion of Plant Secondary Metabolites upon Fermentation of Mercurialis perennis L. Extracts with two Lactobacteria Strains

“…We have extensively studied the phytochemistry of this plant genus for the last ten years. Meanwhile, numerous constituents of M. perennis and further Mercurialis species have been identified, e.g., the piperidine-dione alkaloid hermidin (1) [24][25][26], cinnamic acid depsides, flavonoids [27] and further low-molecular phenolics, terpenoids [26] and n-alkyl resorcinols [23,28,29]. Recently, we reported a first study on the metabolism of constituents upon spontaneous fermentation of M. perennis extracts, as a result of the action of the wild LAB flora [30].…”