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The genus Allochrusa (Caryophyllaceae) comprises nine species, which are native to Central Asia, Turkey, Iran, Afghanistan, and the Caucasus. They have been used in folk medicine and in the preparation of various sweets and detergents, especially in Asian countries. A diversity of secondary metabolites has been reported from the genus Allochrusa, including triterpene glycosides, ecdysteroids, flavonoids, volatile compounds, fatty acids, polysaccharides, pectins, hemicelluloses, and other phytochemicals. In vitro and in vivo pharmacological studies on isolated compound fractions and extracts from Allochrusa species showed anti-inflammatory, adjuvant, hemolytic, cytotoxic, antifungal, analgesic, antioxidant, and other activities. In this review, the chemical compounds and diverse biological activities of the Allochrusa genus are summarized. [ABSTRACT FROM AUTHOR]

An intriguing example of a crystallization‐induced stereochemical switch in the configuration of aza‐Michael reaction products is described. Depending on both the stereochemical purity and stoichiometric ratio of the chiral amine used, the reaction delivers crystalline diastereomers of a different stereochemistry. The optically pure diastereomer smoothly converts to its racemic epimer salt upon the addition of a complementary chiral amine. [ABSTRACT FROM AUTHOR]

Malva species are used for the treatment of cough, digestive problems, asthma, urticaria. Malva nicaeensis is a medicinal food plant like the other Malva species. To the best of our knowledge, no phytochemical studies on Malva nicaeensis have been reported up till now. In the present study, we aimed to assess the antioxidant effect of different extracts of M. nicaeensis, and to isolate the major metabolites of M. nicaeensis. DPPH radical scavenging effect of crude methanol extract, chloroform, ethyl acetate subextracts as well as remaining water extract prepared from the aerial parts of M. nicaeensis were tested. Phytochemical studies on the water and ethyl acetate subextract led to the isolation of a megastigman glycoside; roseoside and indole-3-carboxylic acid. The structures of the isolated compounds were identified on the basis of 1D- and 2D-NMR experiments. Biological activity test results support the ethnobotanical data of the plant. [ABSTRACT FROM AUTHOR]

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]

A novel method of the preparation of (hetero)aryl nitriles based on the fragmentation of the corresponding pentafluorophenylhydrazones is described. The synthesis is metal‐free, proceeds in neutral conditions with no need of protecting group application and provides most nitriles in moderately good yields. The synthesis was performed on ten pentafluorophenylhydrazones with different functional groups within the carbonyl part – the reaction was found to be partially substrate selective. The reaction prefers substrates with aromatic electron donating substituents on the carbonyl part of the hydrazone. The second reaction product, 2,3,5,6‐tetrafluoroaniline, can be easily separated by vacuum distillation. Although the reaction mechanism is yet to be ascertained, all synthetic and spectroscopic data suggest a radical reaction mechanism. [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]

Enantiopure N‐benzyl 6‐oxopipecolic acid, obtained from (S)‐2‐aminoadipic acid, was evaluated under π‐cationic cyclization conditions. If the combination of SOCl2/AlCl3 seems to be superior in terms of the reaction yields, use of PPA, (CF3CO)2O/BF3·Et2O, and Eaton's reagent is also very interesting since in addition to the expected keto‐lactam, reduced‐ and oxidized keto‐lactam, enamides and enamidones containing CF3CO– residue are isolated. Mechanisms leading to these products as well as the ones resulting from their acidic treatment were proposed and discussed with the help, in some cases, of univocal transformations and X‐ray analysis. Enantiopure N‐benzyl 6‐oxopipecolic acid, generated from (S)‐2‐aminoadipic acid, was evaluated under different π‐cationic cyclization conditions. The combination of SOCl2/AlCl3 seems to be superior in terms of the reaction yields. Other activators resulted in a change of the reaction profile and, interestingly, in the diversification of the aza‐heterocyclic systems. [ABSTRACT FROM AUTHOR]

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]

NMR shifts of a series of ten p-substituted diphenyl amine antioxidants in DMSO have been measured as well as evaluated by B3LYP calculations. At 25 °C no correlation between Molar Antioxidant Effectiveness ( AEM ) and NMR chemical shifts of relevant atoms is evident. AEM at 130 °C increases with NMR chemical shifts of nitrogen atoms between aromatic rings and hydrogen atoms bonded to them with very good statistical parameters (except nitro- and nitroso-compounds). This treatment might aid to a very simple estimation of high-temperature AEM values based on NMR shifts (experimental or calculated by quantum-chemical methods) of relevant atoms. Our results confirm that the essential mechanism of the antioxidant action is temperature-dependent. [ABSTRACT FROM AUTHOR]

NMR shifts of N -phenyl- N ′-alkyl-p-phenylenediamines (PPD) in DMSO have been measured as well as evaluated by B3LYP calculations. According to Simon et al. Molar Antioxidant Effectiveness ( AEM ) of PPD antioxidants depends on the bond strength of hydrogens to amine nitrogens between aromatic rings (N A ), to the side aliphatic chain nitrogens (N B ) and to its neighboring tertiary carbon atoms (C T ). AEM increases with NMR shifts of H A , H B , N A and probably also of C T atoms whereas NMR shifts of N B atoms exhibit a reverse trend. This is very surprising because similar reactions at A and B sites are supposed. [ABSTRACT FROM AUTHOR]

In the present study we aimed to identify the α-glucosidase enzyme inhibitory potential of Potentilla inclinata Vill. MeOH and n -BuOH extracts which possessed remarkable α-glucosidase enzyme inhibitory effects with IC 50 values of 1.06 ± 0.02 and 0.93 ± 0.01 μg/ml respectively, compared to that of acarbose (IC 50 31.92 ± 0.17). Thus, BuOH extract was chosen for further phytochemical investigations. A phenolic acid, six flavonol glycosides, and two hydrolysable tannins were isolated from the most active n -BuOH extract of the title plant. Structures of the isolated compounds were elucidated by 1D- and 2D-NMR experiments. All the compounds exhibited remarkable α-glucosidase inhibitory activity compared to the positive control, acarbose. Rutin ( 2 ) showed the highest activity with an IC 50 value of 26.31 ± 0.02 μg/ml. An enzyme kinetics analysis revealed that compounds 5 and 7 were competitive, 4 and 6 noncompetitive, and 3 was uncompetitive inhibitors of α-glucosidase enzyme. Molecular docking studies were performed to get insights into inhibition mechanisms of the isolates considering their inhibition type using various binding sites of the enzyme model we previously reported. [ABSTRACT FROM AUTHOR]

• A number of extracts and isolates of Potentilla speciosa var. speciosa were identified. • The extracts and isolates were tested for α-glucosidase and tyrosinase inhibition. • The butanol extract and Cinnamtannin D1 proved highly potent α-glucosidase inhibitors. • It is the first report of Cinnamtannin D1 occurrence in genus Potentilla. • Molecular docking suggested allosteric binding for Cinnamtannin D1. In order to explore the antidiabetic and anti-pigmentation potential of Potentilla species, which have been used for the treatment of diabetes and some skin problems, α-glucosidase and tyrosinase inhibitory effects of Potentilla speciosa Willd. var. speciosa Willd. were tested. The n -butanol extract showed significant α-glucosidase inhibition (IC 50 = 3.08 ± 0.48 ppm). Phytochemical studies on this extract led to isolation of catechin, miquelianin, tiliroside, and cinnamtannin D1, the occurrence of the latter in the genus Potentilla is reported for the first time in this study. Miquelianin showed the highest inhibitory effect on tyrosinase with an IC 50 value of 86.60 ± 1.90 μM. Cinnamtannin D1 emerged as an excellent α-glucosidase inhibitor with an IC 50 value (0.849 ± 0.014 μM), approximately 53 times higher than the value of the positive control, acarbose. It was found to inhibit α-glucosidase in a noncompetitive manner with a K i value of 0.240 ± 0.010 μM. Molecular modeling studies showed that cinnamtannin D1 most likely bound to an allosteric site of the enzyme. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Extracts and compounds from G. asphodeloides proved potent α -glucosidase inhibitors. • 1 showed the strongest α -glucosidase inhibitory effect among the isolated compounds. • 1 was approximately 61 fold more effective than positive control, acarbose. • 2 , 3 and 4 were competitive; 1 and 6 were uncompetitive inhibitors. • Molecular docking studies gave insights into inhibition mechanisms of the compounds. Abstract Some Geranium species have been used to treat diabetes. To evaluate the scientific basis of this ethnopharmacological use, we aimed to isolate potent α -glucosidase inhibitory metabolites of Geranium asphodeloides Burm. through in vitro bioactivity-guided fractionation. All the tested extracts showed high α -glucosidase inhibitory effect compared to acarbose. Among the tested extracts, the ethyl acetate subextract showed the highest activity with an IC 50 value of 0.85 ± 0.01 µM. A hydrolysable tannin, 1,2,4-tri- O -galloyl- β - d -glucopyranose (1), and five flavonoid glycosides, kaempferol-3- O - α -rhamnopyranoside (2), kaempferol-3- O - α -arabinofuranoside (3), quercetin-3- O - β -glucopyranoside (4), quercetin-3- O - α -rhamnopyranoside (5), and quercetin-3- O - α -rhamnofuranoside (6), were isolated from the ethyl acetate subextract. Their structures were identified by 1D- and 2D-NMR experiments. 1 exhibited the highest α-glucosidase inhibitory effect, approximately 61 times more potent than positive control, acarbose, with an IC 50 value of 0.95 ± 0.07 µM. Also, 2 was more potent than acarbose. An enzyme kinetics analysis revealed that compounds 2 , 3 and 4 were competitive, whereas 1 and 6 uncompetitive inhibitors. Molecular docking studies were performed to get insights into inhibition mechanisms of the isolated compounds in the light of the enzyme kinetic studies using various binding sites of the enzyme model. [ABSTRACT FROM AUTHOR]

The aerial parts of Alchemilla L. species (Rosaceae) are used internally as diuretic, laxative, tonic and externally for wound healing in Turkish folk medicine. Antioxidant effects of the extracts, fractions and isolated compounds from the aerial parts of A. barbatiflora Juz. were investigated with following methods: 1,1-diphenyl-2-picryl-hydrazyl (DPPH), and superoxide radical scavenging (SOD), phosphomolibdenum-reducing antioxidant power (PRAP), ferric-reducing antioxidant power (FRAP) assays. In addition, tyrosinase, α-glucosidase and acetylcholinesterase inhibition activities of samples were analyzed. The methanol extract from the aerial parts of plant was consecutively fractionated into four subextracts; n-hexane, chloroform, and remaining water extracts. Further studies were carried out on the most active water subextract and the fractions obtained from water subextract with column chromatography. Phytochemical studies on active fractions of the water subextract led to the isolation of seven metabolites including catechin (1) and a catechin dimer; procyanidin B3 (2), a flavonol glucuronide; quercetin-3-O-β-D-glucuronic acid (miquelianin) (3) with flavonoid glycosides; quercetin-3-O-β-D-galactoside (hyperoside) (4), quercetin-3-O-β-D-arabinoside (guaiaverin) (5), kaempferol-3-O-β-Dxylopyranoside (6) and kaempferol-3-O-(6"-coumaroyl-β-D-glycoside) (tiliroside) (7). Their structures were elucidated by spectral techniques (1D and 2D NMR). The experimental data verified that procyanidin B3 displayed remarkable enzyme inhibitory activity among the whole isolated compounds. [ABSTRACT FROM AUTHOR]

The synthesized 6-nitroquinolone derivatives were characterized by UV/vis, NMR spectroscopy and the EPR spin trapping technique was applied to monitor the photoinduced generation of non-persistent radical species. The NMR spectra of ethyl 1,4-dihydro-6-nitro-4-oxoquinoline-3-carboxylate ( 1 ) and 1,4-dihydro-6-nitro-4-oxoquinoline-3-carboxylic acid ( 3 ) confirmed the dominance of the oxo-tautomer in dimethylsulfoxide (DMSO) solutions. The electronic absorption spectra of 6-nitroquinolones 1 and 3 with the amino hydrogen at nitrogen of the enaminone system (N–C=C–C=O) revealed the interaction of >NH with the aprotic DMSO solvent, which leads to the formation of the corresponding N -deprotonated species. The photoinduced reactions of 6-nitroquinolones in the aerated DMSO solutions were investigated by monitoring the electronic spectra upon a steady-state irradiation. While the ethyl 1,4-dihydro-1-ethyl-6-nitro-4-oxoquinoline-3-carboxylate ( 2 ) possessing an ethyl group at the nitrogen of the 4-pyridone moiety exhibits a rather low stability upon UVA photoexcitation, the changes in the electronic spectra observed for the derivatives 1 and 3 were attributed to the alterations in the concentration of their N − /NH forms caused by the water absorption in the hygroscopic DMSO, with no evidence of photodecomposition. The photoexcitation (365 nm or 400 nm monochromatic radiation) of 6-nitroquinolones in aerated DMSO solutions containing spin trapping agents revealed the generation of superoxide radical anion spin-adducts, along with further spin-adducts of carbon- and oxygen-centered radicals produced by the interaction of photoexcited nitroquinolone molecules with the solvent. In the scope of various biological activities of quinolone-like compounds, a cytotoxic effect of ethyl 1,4-dihydro-1-ethyl-6-nitro-4-oxoquinoline-3-carboxylate ( 2 ) on cancer human (HeLa) and murine (B16) and non-cancer (NIH-3T3) cell lines was evaluated, demonstrating a rather low cytotoxicity towards studied cell lines. [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.)