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The infusions prepared from some Quercus L. species are used in folk medicine for medicinal purposes and consumed as tea. Quercus pontica K. Koch was selected in this study, for which no phytochemical isolation studies have been performed so far. Quercetin 3-O- β-D-glucopyranoside, kaempferol 3-O-(6”“-O-galloyl)-β-D-glucopyranoside, kaempferol 3-O-β-D-glucopyranoside, kaempferol 3-O-(6”’-coumaroyl-β-D-glucopyranoside, phlorizin, rosmarinic acid, and catechin were isolated from the titled plant for the first time. Some polyphenolic compounds have been shown to inhibit histone deacetylase (HDAC) enzymes. However, there is no study on the any activities of Quercus species in the literature. In this study, we demonstrated that the extract has in vitro pan-HDAC inhibition activity. Through a virtual screening study, the compounds were found to inhibit HDAC7 more strongly than the other HDAC isoforms; therefore, the HDAC7 inhibition activities were studied in vitro. Kaempferol 3-O-β-D-glucopyranoside and kaempferol 3-O-(6’”-coumaroyl-β-D-glucopyranoside) showed the best anti-HDAC7 activity with 37% and 41% inhibition at 500 μM. [ABSTRACT FROM AUTHOR]

The complete structural characterization of synthesized compounds was achieved by the combined use of 1D and 2D NMR techniques, such as SP 1 sp H, SP 13 sp C-HSQC, SP 1 sp H, SP 13 sp C-HMBC, and SP 1 sp H, SP 15 sp N-HMBC. GLO:O90/01feb20:mrc4974-fig-0002.jpg PHOTO (COLOR): 2 1H,13C-HMBC spectrum showing correlations to quaternary carbons C-8'a,9'a, C-4'a,10'a, C-8"a,9"a and C-4"a,10"a in the derivative 5a gl FIGURE S531H,15N-HMBC spectrum (600/61 MHz, DMSO-d6) of the derivative 5c.FIGURE S541H NMR spectrum (600 MHz, DMSO-d6) of the derivative 5d.FIGURE S5513C NMR spectrum (151 MHz, DMSO-d6) of the derivative 5d.FIGURE S5613C NMR spectrum (151 MHz, DMSO-d6) of the derivative 5d showing JC,F couplings. FIGURE S651H,15N-HMBC spectrum (600/61 MHz, DMSO-d6) of the derivative 5f.FIGURE S661H NMR spectrum (600 MHz, DMSO-d6) of the derivative 5g.FIGURE S6713C NMR spectrum (151 MHz, DMSO-d6) of the derivative 5g.FIGURE S681H,15N-HMBC spectrum (600/61 MHz, DMSO-d6) of the derivative 5g.FIGURE S691H NMR spectrum (600 MHz, DMSO-d6) of the derivative 5h.FIGURE S7013C NMR spectrum (151 MHz, DMSO-d6) of the derivative 5h.FIGURE S711H,15N-HMBC spectrum (600/61 MHz, DMSO-d6) of the derivative 5h.FIGURE S721H NMR spectrum (600 MHz, DMSO-d6) of the derivative 5i.FIGURE S7313C NMR spectrum (151 MHz, DMSO-d6) of the derivative 5i.FIGURE S741H,15N-HMBC spectrum (600/61 MHz, DMSO-d6) of the derivative 5i. [Extracted from the article]

Activated enol ethers derived from methyl or ethyl acetoacetate/cyanoacetates or nitriles and pentane-2,4- dione react with pentafluorophenylhydrazine through the primary amino-group to afford pyrazoles bearing a preferred 5-amino- over 5-methyl- or 5-hydroxy-substituent in the resulting 4-substituted pyrazoles. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate and compare the antioxidant capacity and enzyme inhibitory activity of extracts, sub-extracts, and fractions prepared from the aerial parts and roots of A. pseudocartalinica. The phytochemical content of the active extracts was also analyzed. According to the results, ellagic acid (38.42 mg/g) was the major compound in the aerial part methanol extract and catechin (185.30 mg/g) in the root methanol extract. The DPPH inhibition activity of all fractions was monitored, with the most active one (Fr B) reaching an IC 50 value of (4.92±0.59 μg/mL). All the fractions prepared from the aerial parts' water sub-extract showed higher a-glucosidase inhibitory activity than the positive control acarbose. In the tyrosinase assay, Fr B (58.81±7.50 μg/mL) exhibited the highest inhibitory actions among all fractions. The structure of the major substances of the most active fraction were elucidated as quercetin 7-O-β-glucopyranosyl-3-O-β-glucuronopyranoside- (1), and α-[(2-formyl-5-hydroxymethyl)pyrrol-1-yl]aspartic acid (2)., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)