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Phytochemical investigations of the twig and leaf extracts of Uvaria dac Pierre ex Finet & Gagnep. resulted in the isolation and identification of five new highly oxygenated cyclohexenes, uvaridacols M − Q (1 – 3 , 5 , and 6), and six known compounds (4 and 7 – 11). All new structures were elucidated by spectroscopic methods and HRESITOFMS data. The absolute configuration of 1 , 5 , and 6 was confirmed by single X-ray diffraction analysis with Cu Kα radiation. In contrast, other compounds were established by comparing their specific rotation and ECD spectra with those of known compounds. Some of the isolated compounds with sufficient quantity were evaluated for their α-glucosidase inhibitory activity. Of these, (−)-1,6-desoxypipoxide (10) showed α-glucosidase inhibitory activity with an IC 50 value of 28.6 μM. The in silico molecular docking of active compounds was also studied. Phytochemical investigations of the twig and leaf extracts of Uvaria dac Pierre ex Finet & Gagnep. resulted in the isolation and identification of five new highly oxygenated cyclohexenes and six known compounds. Some of the isolated compounds with sufficient quantity were evaluated for their α-glucosidase inhibitory activity. Of these, (−)-1,6-desoxypipoxide (10) showed α-glucosidase inhibitory activities with an IC 50 value of 28.6 μM. [Display omitted] • Five new oxygenated cyclohexenes were isolated from Uvaria dac. • The absolute configuration of uvaridacol M, P, Q were confirmed by single X-ray diffraction analysis with Cu Kα radiation. • Oxygenated cyclohexenes containing a cinnamoyl moiety, such as uvaridacols N and P first reported here. • 1,6-Desoxypipoxide showed α -glucosidase inhibitory activity. • 1,6-Desoxypipoxide was docked into α -glucosidase (PDB ID: 2QMJ) in silico molecular docking. [ABSTRACT FROM AUTHOR]

Four new meroterpenoids, namely nivalones C F (1 – 4), along with a known meroterpenoid, cannabiorcicyclolic acid (5), were isolated from the branches and leaves of Rhododendron nivale. The chemical structures of compounds 1 – 4 were elucidated through comprehensive spectroscopic analyses, including NMR, UV–Vis, IR, ECD spectroscopy, as well as HR-ESI-MS. The isolated compounds were evaluated for their anti-inflammatory and neuroprotective properties. The inhibitory activity of compound 5 against lipopolysaccharide (LPS)-induced nitric oxide (NO) production was initially demonstrated, showcasing an IC 50 value of 21.1 μM. Additionally, both compounds 2 and 5 displayed a notable effect on the viability of H 2 O 2 -damaged SH-SY5Y cells, indicating their significant neuroprotection effects. Four new meroterpenoids 1 – 4 (nivalones C F) and a known meroterpenoid 5 with good anti-inflammatory and neuroprotective effects were isolated from Rhododendron nivale. [Display omitted] [ABSTRACT FROM AUTHOR]

An extensive phytochemical investigation on the rare medicinal plant Semiliquidambar cathayensis (family: Hamamelidaceae) led to the isolation of four new (1 – 4 , named semiliquidacids A–D, respectively) and 25 related known pentacyclic triterpenoids. The new structures with absolute configurations were elucidated by spectroscopic methods, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analysis. Compound 1 represents the first naturally occurring ursane-type triterpenoid featuring an uncommon C-25 formyl group. Compound 4 and oleanolic acid (13) exhibited remarkable inhibitory effects against the ATP-citrate lyase (ACL, an emerging drug target for hyperlipidemia and related metabolic disorders) with IC 50 values of 6.5 and 11.9 μM, respectively. The molecular interaction and binding mode between the bioactive triterpenoids and ACL were elaborated by conducting a molecular docking study. Meanwhile, the chemotaxonomic significance of the isolated triterpenoids has been briefly discussed. [Display omitted] • The rare medicinal plant Semiliquidambar cathayensis was phytochemically investigated. • Four new and twenty-five related known pentacyclic triterpenoids were reported. • Semiliquidacid A is a rare ursane-type triterpenoid featuring a C-25 formyl group. • Semiliquidacid D and oleanolic acid significantly inhibited the ATP-citrate lyase. • A molecular docking study was performed to provide an insight into the binding site. [ABSTRACT FROM AUTHOR]

Diterpenoids occupy an important slot of the natural products diversity space with wide ranges of bioactivities and complex structures, providing potential applications for the development of therapeutics. In this study, we reported four new abietane-type diterpenoids viroxocin B-E (1–4), a new totarane-type diterpenoid viroxocin F (5), and a new sempervirane-type diterpenoid viroxocin G (6) along with four known compounds (7 – 10), isolated and identified from a widely used Traditional Chinese Medicine, Isodon serra (I. serra). Their structures were established by spectroscopic data analysis, experimental and calculated electronic circular dichroism (ECD) data, as well as X-ray diffraction analysis. Compounds 2 , 5 , 7 , 8 and 10 exhibited promising anti-inflammatory activities in lipopolysaccharide (LPS)-induced RAW 267.4 cells, and their inhibition rates on NO production were more than 60% at 10 μM. Compound 7 showed cytotoxicity against human renal cell carcinoma 769P at 20 μM, the inhibition rate was 52.66%. [Display omitted] [ABSTRACT FROM AUTHOR]

Three Stemona alkaloids named stemotuberines A–C (1 – 3) with unique C 17 N frameworks, presumably formed by elimination of the C-11–C-15 lactone ring of the stichoneurine skeleton, were isolated from the roots of Stemona tuberosa. Their structures were elucidated by spectroscopic analysis, X-ray diffraction, and computational methods. Compounds 2 and 3 showed inhibition (IC 50 values of 37.1 and 23.2 μM, respectively) against LPS-induced nitric oxide production in RAW 264.7 cells. In addition, concern was expressed about the reported plant origin (S. sessilifolia) of the recently described alkaloids tuberostemonols O–R (4–7), which should be S. tuberosa. NMR calculations indicated structural misassignment of these compounds except for 6. Isolation of tuberostemonol P (5) from our material of S. tuberosa allowed for a close examination of the spectroscopic data leading to the revised structure 5a. Tuberostemonol R (7) was found to have identical 1H and 13C NMR data to the well-known alkaloid croomine, and therefore its structure including relative stereochemistry must be revised as 7a. [Display omitted] • Three previously undescribed Stemona alkaloids were isolated from Stemona tuberosa. • Compounds 1 – 3 possess unprecedented C 17 N skeletons. • Nitric oxide inhibitory activities of isolated compounds were evaluated. • Putative structures of tuberostemonols P and R were revised. [ABSTRACT FROM AUTHOR]

Eleven new highly oxygenated eremophilane-type sesquiterpenoids were isolated from the whole plant of Synotis solidaginea , including two pairs of C-8 S / R epimers. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis and the absolute configurations of 1 and 9 were confirmed by single-crystal X-ray crystallography using Cu K α radiation. All the isolates were tested for the inhibition of LPS-stimulated NO production in macrophage-like mouse monocytic leukemia RAW264.7 cells. Compound 1 exhibited weak inhibitory effects with an IC 50 of 71.2 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Six previously undescribed diterpenoid glucosides, along with four known compounds, were isolated from the aerial parts of Sigesbeckia glabrescens. The structures and absolute configurations of undescribed compounds were elucidated using extensive spectroscopic techniques, ECD calculations and chemical methods. Compounds 1 and 8 exhibited anti-inflammatory activity against LPS-induced NO production in RAW 264.7 macrophages, with compound 8 demonstrating significant inhibitory activity compared to positive control minocycline, boasting an IC 50 value at 14.20 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Three new xanthone derivatives irpexols A-C (1 – 3) and five known xanthones including three dimeric ones were successfully isolated from Irpex laceratus A878, an endophytic fungus of the family Irpicaceae from the medicinal plant Pogostemon cablin (Blanco) Bentham (Lamiaceae). The structures of these compounds were elucidated by extensive spectroscopic analyses including ultraviolet-visible spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS), and nuclear magnetic resonance (NMR). All of the three new compounds (1 – 3) share a de-aromatic and highly‑oxygenated xanthone skeleton. In addition, the cytotoxic activity of compounds 1 – 8 were evaluated against SF-268, MCF-7, HepG2, and A549 tumor cell lines. The results revealed that compound 6 showed moderate cytotoxic activity with the IC 50 values ranging from 24.83 to 45.46 μM, while the IC 50 values of the positive control adriamycin was ranging from 1.11 to 1.44 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Four previously undescribed isoprenoid flavonoids (2 – 5) were isolated from Sophora davidii , along with five known analogues. The structures of the compounds were established through comprehensive analysis of spectroscopic data, including HRESIMS, 1D and 2D NMR, and absolute configurations determined by theoretical calculations, including ECD and NMR calculation. The cytotoxic effects of the isolated compounds on human HT29 colon cancer cells were evaluated using the MTT assay, compound 1 exhibited cytotoxicity against human HT29 colon cancer cells with an IC 50 value of 8.39 ± 0.09 μM. Studies conducted with compound 1 in HT29 cells demonstrated that it may induce apoptosis and autophagy in HT29 by promoting the phosphorylation of P38 MAPK and inhibiting the phosphorylation of Erk MAPK. Four previously undescribed isoprenoid flavonoids were isolated from Sophora davidii. Compound 1 showed significant inhibitory activity against human HT29 colon cancer cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Five new B- seco -limonoids, namely toonanoronoids A-E (1 – 5), in conjunction with three previously reported compounds, were isolated from the EtOAc extract of the twigs and leaves of Toona ciliata var. yunnanensis. Their structures were elucidated through comprehensive spectroscopic and X-ray crystallographic analysis. The cytotoxic activities of new compounds against five human tumor cell lines (HL-60, SMMC-7721, A549, MCF-7, and SW480) were screened, Compounds 4 and 5 exerted inhibition toward two tumor cell lines (HL-60, SW-480) with IC 50 values between 1.7 and 5.9 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Three new indole alkaloid derivatives, fissindoalkas A-C (1 – 3) together with one known biogenetically related polysubstituted indole alkaloid (4) were isolated from the roots of Fissistigma oldhamii (Hemsl.) Merr. The structures of compounds 1 – 4 were elucidated using comprehensive spectroscopic methods. The inhibitory activities of compounds 1 – 4 against nitric oxide (NO) production induced by lipopolysaccharide (LPS) were evaluated in vitro using mouse macrophage RAW264.7 cells. Compounds 2 and 3 showed potent inhibitory activities on NO production with IC 50 values of 2.52 ± 0.18 and 2.33 ± 0.16 μM. These results indicate that the discovery of indole alkaloid derivatives, from the roots of F. oldhamii , which show significant anti-inflammatory properties, could be of great importance to the research and for the development of novel natural anti-inflammatory agents. [Display omitted] [ABSTRACT FROM AUTHOR]

Michelia champaca L. (Magnoliaceae) was cultivated in large scale for flowers as cosmetic raw materials, whereas the value of its leaves remains to be discovered. Our chemical study on the leaves yielded four new flavonol diglycosides, champaflavosides A–D (1 – 4), together with twenty-three known flavonoid glycosides (5 – 27). Their structures were determined by spectroscopic and chemical methods. Compounds 5 – 21 and 23 – 27 were not previously reported from the genus Michelia , and kaempferol 3- O -rutinoside (22) was obtained from this species for the first time. All the compounds were evaluated for antioxidant activity by four in vitro assays. Compounds 3 – 12 and 20 showed more potent 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than l -ascorbic acid (l -AA). Compounds 2 – 23 , 25 , and 27 exhibited 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical cation scavenging activity superior to l -AA. The ferric reducing antioxidant powers (FRAP) of compounds 2 – 13 , 17 , and 19 were higher than l -AA. Further, eighteen compounds demonstrated cellular reactive oxygen species (ROS) scavenging activity, of which champaflavoside D (4), rhamnetin 3- O -neohesperidoside (8), quercetin 3- O -(6- O - E - p -coumaroyl)-neohesperidoside (9), and liquiritin (27) were more potent than curcumin. The results revealed that the renewable leaves of M. champaca are a rich source of flavonoids and antioxidants. [Display omitted] • Michelia champaca has been widely cultivated for flowers as cosmetic raw materials. • The chemical constituents other than volatile oil in the leaves remain unknown. • Four new and 23 known flavonoid glycosides were isolated from the leaves. • Our research results revealed that the leaves are a rich source of antioxidants. [ABSTRACT FROM AUTHOR]

Five unusual seco-nortriterpenoids, 3 β -hydroxy-20,21-seco-30-nortaraxastan-20,21-dioic acid (1), 3 β -hydroxy-20,21-seco-30-nortaraxastan-20-oic-21-oate (2), 3 β -hydroxy-20-oxo-21,22-seco-30-nortaraxastan-22-oic acid (3), 3 β -hydroxy-19-oxo-20,21-seco-29,30-nortaraxastan-21-oic acid (4) and 3 β -hydroxy-19-oxo-20,21-seco-19-norlupan-21-oic acid (5) were isolated and elucidated from the anti-inflammatory activity fraction of the ethanol extract of Cirsium setosum. The structures of these compounds were established through spectroscopic methods. Preliminary biological assays showed that compounds 1 – 5 had significant inhibitory effect on NO production on lipopolysaccharide-stimulated RAW 264.7 cells, and compound 1 showed the strongest anti-inflammatory activity. This type of ring-opening compound is the first seco-triterpenoid structure discovered from the genus of Cirsium. [Display omitted] [ABSTRACT FROM AUTHOR]

Melodinus axillaris W.T.Wang has been widely used as an important medicine in China. In the folk of China, its whole plant has been used for fractures, rheumatic heart disease, testitis, hernia, abdominal pain, and dyspepsia, etc. Despite its extensive use, there is a shortage of literature investigating the specific bioactive compounds and underlying mechanisms responsible for their anti-inflammatory effects. This knowledge gap serves as the primary impetus for conducting this study, which aims to shed light on the previously unexplored therapeutic potential of M. axillaris. This study aims to investigate the material basis and potential mechanism of anti-inflammatory activity of M. axillaris. Compounds were isolated from the 95% ethanol extract of M. axillaris using a systematic phytochemical method. The structures were established by extensive spectroscopic analysis, including 1D and 2D NMR, HR-ESI-MS, ECD calculation, and DP4+ analysis. The anti-inflammatory activities of ethanol extract and compounds from M. axillaris were tested by an inflammation model of LPS-stimulated RAW264.7 cells in vitro. Western blot analysis was employed to evaluate the expressions of COX-2, iNOS, and NF-κB signaling pathways, aiming to elucidate the underlying mechanisms. Eleven undescribed monoterpenoid indole alkaloids (MIAs), axillines A−K (1 – 11), along with thirteen known analogs were isolated from M. axillaris. Compound 1 was the first representative of vincadine alkaloid with unprecedented 6/5/9/6/6 skeletons. Compounds 1 – 11 and ethanol extract showed significant anti-inflammatory effects in vitro. Among them, compound 2 had the best activity of inhibiting NO release (IC 50 = 3.7 ± 0.9 μM). Additionally, subsequent Western blot analysis revealed that 2 could significantly inhibit the up-regulation of NF-κB signaling pathways, iNOS, and COX-2 in LPS-stimulated RAW264.7 cells, thereby demonstrating its anti-inflammatory activity. This study provides support for the traditional use of M. axillaris in terms of its anti-inflammatory properties and highlights the potential of MIAs as promising candidates for further development as anti-inflammatory drugs. [Display omitted] • Eleven undescribed monoterpenoid indole alkaloids (MIAs) were isolated from M. axillaris. • Compound 1 was the first representative of vincadine alkaloid with 6/5/9/6/6 skeletons. • These MIAs were isolated exhibited significant anti-inflammation activity. • Compound 2 inhibited inflammation by NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Five new sesquiterpenoids, dictamtrinorguaianols E and F (1–2), and dictameudesmnosides F, G, and H (3–5), along with seven known sesquiterpenoids (6–12) were isolated from Dictamnus dasycarpus Turcz. The structures of all new compounds were characterized by spectroscopic methods, including UV, IR, HR-ESI-MS, and 1D and 2D NMR. The In-vitro anti-proliferative activities of all the compounds against two human cancer cell lines (SW982 and A549) were evaluated by CCK-8 assay. Compounds 1 and 4 showed medium anti-proliferative activity against SW982 cells, with IC 50 values of 3.49 ± 0.10 and 6.42 ± 1.23 μM, respectively. Additionally, compounds 2 , 7 , and 8 exhibited medium anti-proliferative activity against A549 cells, with IC50 values ranging from 0.80 ± 0.05 to 6.60 ± 0.46 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Phytochemical study on the roots of a medicinal plant Ferula communis L. (Apiaceae) resulted in the isolation of 20 sesquiterpenes including 12 previously undescribed compounds, dauferulins A–L (1 − 12). The detailed spectroscopic analysis revealed 1 – 12 to be daucane-type sesquiterpenes with a p -methoxybenzoyloxy group at C-6. The absolute configurations of 1 – 12 were deduced by analysis of the ECD spectra. Dauferulins A–L (1 – 12), known sesquiterpenes (13 − 20), and analogues (14a – 14l) derived from 6- O - p -methoxybenzoyl-10α-angeloyloxy-jeaschkeanadiol (14) were evaluated for their effects on AMPK phosphorylation in human hepatoma HepG2 cells as well as inhibitory activities against erastin-induced ferroptosis on human hepatoma Hep3B cells and IL-1β production from LPS-treated murine microglial cells. [Display omitted] • The roots of Ferula communis L. were investigated to isolate 20 sesquiterpenes. • Among them, dauferulins A–L were assigned as new daucane-type sesquiterpenes. • Their structures were elucidated by spectroscopic analysis. • Daucane-type sesquiterpenes and their analogues were evaluated for effects on AMPK phosphorylation. • Their anti-ferroptosis anti-neuroinflammatory activities were also assessed. [ABSTRACT FROM AUTHOR]

Angiotensin I-converting enzyme (ACE) inhibition is currently a common method for the treatment and control of hypertension. In this study, four new (1–4) and one known (5) cycloartane triterpenoids were isolated from the leaves of Swietenia macrophylla by chromatographic techniques and identified by their spectroscopic data and a comprehensive comparison of published data. The triterpenoids were evaluated for their ACE inhibitory potential using in vitro inhibition assays and in silico methods. The inhibition assay and enzyme kinetics results showed that the most active triterpenoid, compound 4 , inhibited ACE in a mixed-type manner with an IC 50 value of 57.7 ± 6.07 μM. Computer simulations revealed that compound 4 reduces the catalytic efficiency of ACE by competitive insertion into the active pocket blocking the substrate, and the binding activity occurs mainly through hydrogen bonds and hydrophobic interactions. The study showed that S. macrophylla can be a source of bioactive material and the ACE inhibitory triterpenoid could be a potential antihypertensive agent. [Display omitted] • Four new cycloartane triterpenoids were isolated from Swietenia macrophylla. • 3β,16β-dihydroxy-29-norcycloartan-24-one (4) inhibited ACE in a mixed-type manner. • Hydrogenation at C-16 and substitution by the carbonyl group at C-24 enhanced the ACE inhibitory activity of the triterpenoids. • Computational simulation analyses showed that hydrogen bonds were the major binding forces. [ABSTRACT FROM AUTHOR]

In this research, five new indolequinazoline alkaloids (1 – 5), along with six known indolequinazoline alkaloids (6 – 11) were obtained from the fruits of Tetradium ruticarpum. Their structures were elucidated through comprehensive spectroscopic data of 1D and 2D NMR, HRESIMS and ECD spectra. Additionally, all isolates were assayed for their SIRT1 inhibitory activities in vitro and compounds 2 , 7 , 10 and 11 exhibited activities with IC 50 values ranged from 43.16 to 118.35 μM. Eleven indolequinazoline alkaloids, including five undescribed compounds, were isolated from the fruits of Tetradium ruticarpum and their SIRT1 inhibitory activities were assessed. [Display omitted] [ABSTRACT FROM AUTHOR]

Aspercitrininone A (1), a novel polyketide featuring an unprecedented tetracyclic 6/6/6/5 spiral skeleton, was obtained from the rice fermentation cultures of the fungus Aspergillus cristatus together with five known compounds (2 – 6). Their structures were determined by HRESIMS data, 1D and 2D NMR spectroscopic analysis, and electronic circular dichroism (ECD) calculations. Aspercitrininone A was revealed as a new type of C/D cycle spiral structure and an unusual addition product of o-quinoid form citrinin with 2-methylterrefuranone. Compounds 1 , 4 , and 5 exhibited potent antibacterial activities with minimal inhibitory concentration (MIC) values from 13.2 to 67.3 μg/mL against four strains of human pathogenic bacteria in vitro. [Display omitted] • A novel polyketide aspercitrininone A was isolated from rice cultures of Aspergillus cristatus. • Aspercitrininone A possessed an unprecedented tetracyclic 6/6/6/5 spiral skeleton. • It could be formed by o-quinoid form citrinin with 2-methylterrefuranone through Michael addition reaction. • Aspercitrininone A exhibited antibacterial activities. [ABSTRACT FROM AUTHOR]

Four new steroidal glycosides (1–4), including two steroidal saponins named lililancifoloside B and C (1 – 2), one pregnane glycoside named lililancifoloside D (3), and one C22-steroidal lactone glycoside named lililancifoloside E (4), together with five known ones (5–9), were isolated from the bulbs of Lilium lancifolium Thunb. By using spectroscopic analysis, including 1D, 2D NMR, and HR-ESI-MS, the structures of 1–4 were elucidated. All isolates were tested for their cytotoxic potential against the MCF-7, MDA-MB-231, HepG2, and A549 cell lines. Compound 6 distinguished out among them, IC 50 values of 3.31, 5.23, 1.78, and 1.49 μM against the four cell lines, respectively. Other compounds such as compound 3 , 5 , and 9 have also shown specific cytotoxic activity. Next, studies showed that compound 6 might cause HepG2 cells to undergo a cell cycle arrest during the G2/M phase and apoptosis. [Display omitted] • Four new steroidal glycosides were isolated from the bulbs of Lilium lancifolium Thunb.. • The cytotoxicity of all isolates against MCF-7, MDA-MB-231, HepG2, and A549 cell lines were investigated. • Compound 6 displayed significant cytotoxic activitity against all tested cell lines. • Studies revealed that compound 6 could induce cell cycle arrest at G2/M phase and apoptosis in HepG2 cells. [ABSTRACT FROM AUTHOR]

Eight undescribed alkaloids named corydalisine D-K (1 – 7), including one isoquinoline benzopyranone alkaloid (1), one benzocyclopentanone alkaloid (2), four benzofuranone alkaloids (3 , 4 , and 5a / 5b) and two protoberberine alkaloids (6 and 7), along with fourteen known ones, were isolated from the Corydalis saxicola. Their structures, including absolute configurations, were unambiguously identified using spectroscopic techniques, single-crystal X-ray diffraction and electron circular dichroism calculation. Compounds 2 , 14 and 21 exhibit antiproliferative activity against five cancer cell lines. The aporphine alkaloid demethylsonodione (compound 14), which exhibited the best activity (IC 50 = 3.68 ± 0.25 μM), was subjected to further investigation to determine its mechanism of action against the T24 cell line. The molecular mechanism was related to the arrest of cell cycle S-phase, inhibition of CDK2 expression, accumulation of reactive oxygen species (ROS), induction of cell apoptosis, inhibition of cell migration, and activation of p38 MAPK signaling pathway. The results indicated that 14 could be used as a potential candidate agent for further development of anti-bladder transitional cell carcinoma. [Display omitted] • Eight new alkaloids were characterized from the DCM extract of Corydalis saxicola Bunting. • Compound 14 as a CDK2 inhibitor further accelerated apoptotic rate of T24 cells and induced apoptosis by activating the p38 MAPK signaling pathway dependent on the ROS levels. [ABSTRACT FROM AUTHOR]

As our ongoing searching for the bioactive natural terpenoids, nine ent -kauranoids (1 – 9), including three previously undescribed ones (1 , 2 , and 9), were isolated from the aerial parts of Isodon amethystoides. Their structures were elucidated on the basis of spectroscopic data analysis, including NMR, MS, and ECD. Compounds 1 and 2 were a pair of tautomeric compounds, which was confirmed by the HPLC analysis and low temperature NMR testing. The underlying mechanism of the tautomer was proposed as an intramolecular S N 2 reaction, which was explained by quantum chemical calculation. The HOMO-LUMO gap and the free energy revealed the spontaneous of the tautomeric of the 1 and 2. Additionally, the similar phenomena were also found in the two groups of known compounds 3 and 4 and 6 and 7 , respectively. Apart from the tautomer, compounds 3 and 4 can be hydrolyzed into 5 through ester hydrolysis in CDCl 3 , while compounds 6 , 7 can be hydrolyzed into 8 through ester hydrolysis. These phenomena were also confirmed through HPLC analysis and low temperature nuclear magnetic resonance tests and the mechanism was studied using quantum chemical calculation. [Display omitted] [ABSTRACT FROM AUTHOR]

Drynaria quercifolia is an epiphytic fern distributed all over Bangladesh with traditional use in treating neurological disorders and other ailments. Although several pharmacological activities of D. quercifolia have been investigated, the neuroprotective potential of this plant is still unexplored. In this study, we evaluated the in vitro anticholinesterase and antioxidant activities of D. quercifolia and the neuroprotective effect in scopolamine-induced memory-impaired mouse model. The crude methanol extract (DCM) of the plant was fractionated to prepare n-hexane (DHF), chloroform (DCF), ethyl acetate (DEF), and aqueous (DAF) factions. All the fractions were evaluated for anticholinesterase activity by modified Ellman's method and the antioxidant activity by several in vitro assays such as DPPH and hydroxyl free radicals scavenging, reducing power, and inhibition of brain lipid peroxidation. The effect of the most active fractions (both DCF and DEF) on learning and memory was assessed in scopolamine-induced mouse model of memory-impairment by Morris water maze tasks. Biochemical assays were performed in brain tissue. The active compound was isolated and characterized by chromatographic, spectroscopic, and molecular docking methods. Phytochemical analysis demonstrated a high content of phenolic and flavonoid in DEF. In vitro studies revealed a strong antioxidant power of DEF and anticholinesterase activity of DCF. Both the DCF and DEF significantly (P˂0.05) reduced the escape latency time in the Morris's water maze tasks, and increased the time spent in the northeast quadrant in the probe trial. Biochemical data demonstrated that treatment with DCF and DEF at different doses significantly (P˂0.0001) inhibited acetylcholinesterase activity, restored GSH levels, and reduced MDA levels in the brain of scopolamine-induced memory-impaired mice, indicating the protective effect of D. quercifolia , possibly by acetylcholinesterase inhibition and oxidative stress prevention. Chromatographic methods of separation led to he isolation of catechin and protocatechuric acid from DEF and 3,4-dihydroxy benzoic acid from DCF. The structure of the compounds was determined by studies of their 1H-NMR spectra. Molecular docking as well as in vitro study suggests the anticholinesterase and antioxidant activity of the isolated compounds. Our study suggested that the extracts of D. quercifolia , due to anticholinesterase and antioxidant activity, ameliorate the scopolamine-induced memory impairment in mice and thus may represent therapeutics in the treatment of Alzheimer's disease. [Display omitted] • The chloroform and ethyl acetate fraction of Drynaria quercifolia rhizome exhibited considerable anticholinesterase and antioxidant activity in vitro. • Both the fractions significantly improved learning and memory in scopolamine-induced memory-impaired mice via cholinesterase & lipid peroxidation inhibition activity, and non-enzymes augmentation. • The predominant compounds were found to be 3, 4-dihydroxybenzoic acid in the chloroform fraction, and catechin & 2, 3, 4-trihydroxybenzoic acid in the ethylacetate fraction, which were responsible for both anticholinesterase and antioxidant activities as evidenced from in vitro and molecular docking studies. • These results support the traditional use of D. quercifolia in the neurological disorder and suggest that both the chloroform and ethyl acetate fraction of the plant may represent therapeutics in the prevention or treatment of AD. [ABSTRACT FROM AUTHOR]

Eleutherine bulbosa (Mill.) Urb. is a medicinal and edible plant with various benefits for humans and animals. In this work, four new phenolic constituents (1 – 4), along with six known phenolic compounds (5 – 10) were obtained from the red bulbs of E. bulbosa. Their structures with absolute configurations were characterized by extensive spectroscopic analysis, combined with HR-ESI-MS and quantum mechanical electronic circular dichroism (ECD). Compounds 1 and 2 are novel homologous and heterodimers, respectively, featuring an unusual spiro ring system. All isolated phenolic constituents were tested for their antibacterial effects. The results revealed four phenolic compounds 1–3 and 7 showed moderate antibacterial activity against Bacillus subtilis, Staphylococcus aureus a nd Escherichia coli with minimum inhibitory concentration (MIC) values ranging from 15.6 to 250.0 μg/mL. [Display omitted] • Ten phenolic constituents were isolated from the red bulbs of Eleutherine bulbosa. • Compounds 1 and 2 are novel homologous and heterodimers, respectively, featuring an unusual spiro ring system. • Four phenolic compounds 1–3 and 7 showed moderate antibacterial activity with MIC values ranging from 15.6 to 250.0 μg/mL. [ABSTRACT FROM AUTHOR]

Six new compounds, including two depsidones garciculendepsidones A and B (1 and 2), one prenylated xanthone garciculenxanthone (3) and three dimeric xanthones bigarciculenxanthones A–C (4 – 6), were isolated from the twigs and leaves of Garcinia esculenta Y. H. Li. Their structures were elucidated based on comprehensive analyses of spectral data, including HRESIMS, 1D and 2D NMR, and ECD calculation. All the isolates were tested for their cytotoxicity against five human cancer cell lines (myeloid leukemia HL-60, lung cancer A-549 cells, hepatocellular carcinoma SMMC-7721, breast cancer MDA-MB-231 and colon cancer SW480), among them, compounds 3 – 5 displayed cytotoxic potential, especially garciculenxanthone (3) had the lowest IC 50 value of 8.2 μm for lung cancer A-549 cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Three new phenolic glycosides (1 – 3) and a new lignan glycoside (4), together with five known compounds (5 – 9) were isolated from the ethanol extract of the aerial part of Gaultheria leucocarpa var. yunnanensis (Franch.) T.Z.Hsu & R.C.Fang. Their structures were determined on the basis of spectroscopic techniques, experimental and calculated ECD spectra, acid hydrolysis, and enzymatic hydrolysis experiments. All the isolates were evaluated for their anti-inflammatory and antioxidant activities. Compounds 7 and 8 exhibited inhibitory effects against the LPS-induced production of NO with IC 50 of 63.71 and 10.66 μM, respectively, compared to L-NMMA having an IC 50 of 6.95 μM. Besides, compound 7 also represented significant DPPH radical scavenging activity with EC 50 of 18.75 μM, comparable with vitamin C (EC 50 = 15.77 μM). [Display omitted] • Four new (1 – 4) and five known (5 – 9) compounds were isolated from Gaultheria leucocarpa var. yunnanensis. • Compounds 7 and 8 exhibited moderate inhibition against LPS-induced NO production. • Compound 7 showed a comparable DPPH radical scavenging effect to vitamin C. [ABSTRACT FROM AUTHOR]

Three undescribed compounds (1 – 3), including two butenolides and one indol alkaloids. Together with twenty-one known compounds (4 – 24) were isolated and identified from Lepidium obtusum Basin. Their structures were elucidated by spectroscopic analysis and ECD calculations. The isolated compounds were tested for their antimicrobial, antioxidant, and anti-inflammatory activities. Among them, compounds 11 , 12 , 14 , 21 and 23 showed moderated antimicrobial activities against (Candida albicans , E. coli , Staphylococcus aureus). Compounds 11 , 12 , 14 , 15 , 17 and 18 exhibited potent antioxidant activities against ABTS and DPPH. Compound 1 exhibited moderated anti-inflammatory activities. Compounds 4 – 24 were isolated from this plant for the first time. [Display omitted] [ABSTRACT FROM AUTHOR]