Phenolic Glycosides from Exostema mexicanum Leaves

Abstract

Carbohydrates U 0500 Phenolic Glycosides from Exostema mexicanum Leaves -[isolation, structure determination and in vitro cytotoxicity of glycosides (I) and related, novel acylated flavonol glycosides]. -(FROELICH, S.; SIEMS*, K.; HERNANDEZ, M. A.; IBARRA, R. A.; BERENDSOHN, W. G.; JENETT-SIEMS, K.; Pharmazie 61 (2006) 7, 641-644; Inst.

Acylated flavonol tri- and tetraglycosides in the flavonoid metabolome of Cladrastis kentukea (Leguminosae)

“…The location of the additional Rha residue and the sites of acylation for the latter were confirmed using chemical shift and HMBC data, as described for 39 and 40, and the absolute configurations of the constituent monosaccharides were established as D-Gal and L-Rha (Section 3.5). The chemical shift assignments for the 1 H and 13 C resonances of the glycosyl moieties of 37 and 38 were found to be in good agreement with those for the corresponding quercetin analogues obtained by Itoh et al (2002) Although Froelich et al (2006) obtained 37 from dichloromethane extracts of the leaves of Exostema mexicanum (Rubiaceae), only a partial set of 1 H NMR assignments was given (which are in accordance with the data in Table 4), and no 13 C NMR assignments were presented. From LC-UV analysis of the pure preparations of the 4E and 4Z isomers (21 & 22) of the kaempferol 3-O-coumaroyltriglycosides, the elution order of 4E, 4Z was established and differences were noted in the UV spectra, with the shoulder at c. 350 nm on band I (k max = 316 nm) being more intense in the spectrum of the 4Z isomer than the 4E isomer, making band I appear broader in the former (Supplementary Information).…”

“…6)]-(4-Op-coumaroyl-b-D-galactopyranoside)-7-O-a-L-rhamnopyranoside, isolated from Exostema mexicanum A. Gray (Rubiaceae)(Froelich et al, 2006) Itoh et al (2002). reported two quercetin and four isorhamnetin glycosides containing the 3-O-rhamnosyl(1 ?2)[rhamnosyl(1 ?…”

Latin American databases of natural products: biodiversity and drug discovery against SARS-CoV-2

“…LAIPNUDELSAV_029 and LAIPNUDELSAV_031 corresponding a 4-phenylcoumarins with O-glycosidic bonds in C-7 and the hydroxyl in C-1′ of sugar residues, 54 while UPMA-2V_0266 a derivative of caffeic acid. 55 …”

“…LAIPNUDELSAV_029 and LAIPNUDELSAV_031 corresponding a 4-phenylcoumarins with O-glycosidic bonds in C-7 and the hydroxyl in C-1 0 of sugar residues, 54 while UPMA-2V_0266 a derivative of caffeic acid. 55 These three compounds share with the cocrystallized ligand (CMU) the hydrogen bridge interaction with Ser294A and Lys345A residues, while we observed additional interactions with Val292, Leu346 and His 250 residues with these natural products.…”

Plants of the Rubiaceae Family with Effect on Metabolic Syndrome: Constituents, Pharmacology, and Molecular Targets

“…Exosterma caribaeum and E. mexicanum are traditionally used for treating malaria, fever, and high blood glucose [31,32]. These plants are rich in coumarins and phenylcoumarins, with identified compounds such as 5-O-B-D-galactosyl-7-methoxy-3',4'-dihydroxy-4-phenylcoumarin; 7,4',5'-trihydroxy-4-pheny1-5,2'-oxidocoumarin and 7,4'-dimethoxy-5'-hydroxy-4-phenyl-5,2'-oxido-coumarin; and monoterpenoid indole alkaloids such as phenyl styrene, chloroquine, quinine, and chlorogenic acid [33,34]. Notably, chlorogenic acid has been found to exert hypocholesterolemic and antihyperglycemic effects [35].…”