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Abstract Five limonoids isolated from the seeds of Chisocheton siamensis were tested for their antimalarial activity against Plasmodium falciparum, antimycobacterial activity against Mycobacterium tuberculosis and cytotoxic activity against NCI-H187 (human [...]

Phytochemical investigations of the twig and leaf extracts of Goniothalamus tortilipetalus resulted in the isolation and identification of two new alkaloids, goniotortiline ( 1 ) and goniotortilactam ( 2 ), three new styryl lactone derivatives, goniotortilactone ( 3 ) and goniotortilols A ( 4 ) and B ( 5 ), and 25 known compounds. Their structures were elucidated by spectroscopic methods and HRESITOFMS data. Compounds 5 , 13 , 15 , 16 , 22 , and 30 inhibited nitric oxide (NO) production with IC 50 values ranging from 8.7 ± 0.1 to 17 ± 1 μM, revealing stronger effects than the standard drug, dexamethasone (IC 50 16.9 ± 2.2 μM), and compound 30 possessed the most potent NO production inhibition. Compounds 12 and 29 demonstrated notable efficacy in enhancing glucose consumption with IC 50 values of 77 ± 4 and 66 ± 4 μM, respectively, while their glucose uptakes were 1.7- and 2-fold, respectively.

Mathurameha is a traditional Thai herbal formula with a clinically proven effect of blood sugar reduction in patients with diabetes mellitus, but its anti-diabetic complication potential is largely unknown. This study aimed to elucidate the effects of Mathurameha and its underlying mechanisms against high glucose-induced endothelial dysfunction in human endothelial EA.hy926 cells. After confirming no cytotoxic effects, the cells were treated with normal glucose (NG), high glucose (HG), or high glucose plus Mathurameha (HG + M) for 24 h. A quantitative label-free proteomic analysis using the sequential window acquisition of all theoretical mass spectra (SWATH-MS) approach identified 24 differentially altered proteins among the three groups: 7 between HG and NG, 9 between HG + M and NG, and 13 between HG + M and HG. Bioinformatic analyses suggested a potential anti-diabetic action through the epidermal growth factor (EGF) pathway. Subsequent functional validations demonstrated that Mathurameha reduced the EGF secretion and the intracellular reactive oxygen species (ROS) level in high glucose-treated cells. Mathurameha also exhibited a stimulatory effect on nitric oxide (NO) production while significantly reducing the secretion of endothelin-1 (ET-1) and interleukin-1β (IL-1β) in high glucose-treated cells. In conclusion, our findings demonstrated that Mathurameha attenuated high glucose-induced endothelial dysfunction through the EGF/NO/IL-1β regulatory axis. SIGNIFICANCE: This study reveals the potential of Mathurameha, a traditional Thai herbal formula, in mitigating high glucose-induced endothelial dysfunction, a common complication in diabetes mellitus. Using proteomics and bioinformatic analyses followed by functional validations, the present study highlights the protective effects of Mathurameha through the EGF/NO/IL-1β regulatory axis. These findings support its potential use as a therapeutic intervention for diabetic vascular complications and provide valuable information for developing more effective anti-diabetic drugs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Exposure to cadmium (Cd) results in bioaccumulation and irreversible damage; this encourages an investigation of alternatives to address Cd toxicity, using natural compounds. Lysiphyllum strychnifolium , a well-known Thai medicinal plant, was investigated for its phytochemical compounds and corresponding bioactivities, including antioxidant and anti-cytogenotoxic effects against Cd toxicity in HEK293 renal and HDF dermal cell models. The crude extract of L. strychnifolium (LsCrude) was partitioned into four fractions, using sequential polarity solvents (hexane, dichloromethane, ethyl acetate, and water, denoted as LsH, LsD, LsE, and LsW, respectively). The extraction yields were 1.79 %, 5.08 %, 8.53 %, and 70.25 % (w/w), respectively. Phytochemical screening revealed the presence of tannins, alkaloids, and flavonoids in LsCrude and its fractions, except for LsH. LsE exhibited the highest concentrations of phenolics (286.83 ± 6.83 mg GAE/g extract) and flavonoids (86.36 ± 1.29 mg QE/g extract). Subsequent 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging and ferric-reducing ability of plasma (FRAP) reducing powder assays demonstrated the high antioxidant capacity of LsCrude and its fractions. The lowest IC 50 value (9.11 ± 0.43 μg/mL) in the DPPH assay corresponded to LsW, whereas the highest total FRAP value (6.06 ± 0.70 mg QE Eq./g dry mass) corresponded to LsE. MTT and alkaline comet assays revealed the lack of toxicity of the extracts, which were considered safe. Upon exposure to Cd at the CC 50 level, HEK293 cells treated with LsE suppressed Cd-induced damage. HDF cells treated with LsCrude, LsD, or LsE attenuated Cd-induced damage. In the pre-treatment, LsD protected the HDF cells against Cd-mediated cytogenotoxicity. These anti-cytogenotoxic potentials are likely due to the antioxidant properties of the phytochemicals. Our findings highlight the cyto-geno-protective properties of L. strychnifolium stem extracts against Cd toxicity in HEK293 and HDF cells, and provide a novel approach for combating oxidative stress and DNA damage caused by environmental pollutants., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors gratefully acknowledge the financial support from the Faculty of Pharmaceutical Sciences, Prince of Songkla University, and National Science, Research and Innovation Fund (NSRF) and Prince of Songkla University (Grant No PHA6601315S). The authors also would like to thank the Faculty of Pharmaceutical Sciences, and Phytomedicine and the Pharmaceutical Biotechnology Excellence Center (PPBEC) for providing laboratory facilities. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

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., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The first phytochemical investigation of the twig extract of Uvaria leptopoda resulted in the isolation and identification of three new tetrahydroxanthene-1,3(2 H )-diones, uvarialeptones A-C, two new oxidized hexadiene derivatives, uvarialeptols A and B, together with ten known compounds. Their structures were elucidated by spectroscopic techniques and mass spectrometry. Uvarialeptones A and B were unprecedented tetrahydroxanthene-1,3(2 H )-dione dimers which exhibited a cyclobutane ring via [2 + 2] cycloaddition from uvarialeptone C and 9a- O -methyloxymitrone, respectively. The structure of uvarialeptone A was confirmed by X-ray diffraction analysis using Mo Kα radiation. Compound 3 inhibited NO production at an IC 50 value of 6.7 ± 0.1 μM.

Three previously undescribed aporphine alkaloids, phaeanthuslucidines E-G, one previously undescribed naphthoquinone derivative, phaeanthusnaphthoquinone, and three known compounds were isolated from an EtOAc extract of the leaves of Phaeanthus lucidus Oliv. The structures of all previously undescribed compounds were established through extensive spectroscopic investigations and high-resolution mass spectroscopy. The 6aR configuration of phaeanthuslucidines E-G was assigned by comparing their ECD spectra and specific rotation values with the reported known compounds. Some isolated compounds were evaluated for their α-glucosidase inhibitory activity. Among these compounds, phaeanthuslucidine E showed the highest α-glucosidase inhibitory activity with an IC 50 value of 17.9 ± 0.4 μM. The molecular docking of phaeanthuslucidine E was further studied., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Surat Laphookhieo reports financial support was provided by National Research Council of Thailand. Surat Laphookhieo reports a relationship with National Research Council of Thailand that includes: funding grants and travel reimbursement. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Medicinal plants have long been a source of lead compounds for drug discovery. Among these, the Annonaceae family has gained recognition for its potential to yield novel compounds, particularly those that can be used in the development of drugs targeting chronic diseases like diabetes mellitus (DM). We employed various chromatographic methods to isolate bioactive compounds from the roots, leaves, and twigs of Uvaria dulcis Dunal. We used spectroscopic methods to determine the chemical structures of these compounds. We successfully identified twelve known compounds from various parts of U. dulcis : patchoulenon, polygochalcone, 2'3'-dihydroxy-4',6'-dimethoxydihydrochalcone, 2',3'-dihydroxy-4',6'-dimethoxychalcone, chrysin, techochrysin, 8-hydroxy-5,7-dimethoxyflavanone, pinocembrin, 3-farnesylindole, onysilin, cinchonain la, and cinchonain lb. Interestingly, cinchonain la and cinchonain lb exhibited more potent anti-α-glucosidase activity than acarbose (standard drug), with IC 50 values of 11.88 ± 1.41 μg/mL and 15.18 ± 1.19 μg/mL, respectively. Cinchonain la inhibited the DPP-IV enzyme, with IC 50 value lower than the standard compound (diprotin A) at 81.78 ± 1.42 μg/mL. While 2',3'-dihydroxy-4',6'-dimethoxychalcone show more potent inhibitory effect than standard drug with IC 50 value of 8.62 ± 1.19 μg/mL. Additionally, at a concentration of 10 μg/mL, cinchonain lb and 2',3'-dihydroxy-4',6'-dimethoxychalcone promoted glucose uptake in L6 myotubes cells to the same extent as 100 nM insulin. These findings suggest that cinchonain la, cinchonain lb, and 2',3'-dihydroxy-4',6'-dimethoxychalcone are the U. dulcis -derived bioactive compounds that hold promise as potential structures to use in the development of anti-diabetic drugs., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Two new styryl lactone derivatives, goniothapic acids A ( 1 ) and B ( 2 ), and 18 known compounds, were isolated from the twig and leaf extracts of Goniothalamus tapis Miq. The structures of new compounds were characterised by spectroscopic methods and HRESITOFMS. Their absolute configuration was established by comparing the experimental and calculated ECD spectra. Eleven compounds were evaluated for their α-glucosidase inhibitory activity. Of these, (-)-goniothalamin ( 5 ) and oldhamactam ( 16 ) showed the best α-glucosidase inhibitory activity with IC 50 values of 54.8 and 57.9 µM, respectively.

The first phytochemical investigation of the twigs of Phaeanthus lucidus Oliv. resulted in the isolation and identification of four undescribed alkaloids, including two aporphine dimers, phaeanthuslucidines A and B, a hybrid of aristolactam-aporphine, phaeanthuslucidine C, and a C-N linked aporphine dimer, phaeanthuslucidine D, together with two known compounds. Their structures were determined by extensive analysis of spectroscopic data, and by comparison of their spectroscopic and physical data with previous reports. Phaeanthuslucidines A-C and bidebiline E were analysed and resolved by chiral HPLC to yield the (R a ) and (S a ) atropisomers, whose absolute configurations were respectively determined by ECD calculations. Phaeanthuslucidines A and B, bidebiline E, and lanuginosine showed α-glucosidase inhibitory activities with IC 50 values in the range of 6.7-29.2 μM. Moreover, molecular docking simulations of α-glucosidase inhibition of active compounds were studied., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Surat Laphookhieo reports financial support was provided by Mae Fah Luang University. Surat Laphookhieo reports financial support was provided by National Research Council of Thailand., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Two new cassane diterpenoids, 14β-hydroxycassa-11(12),13(15)-dien-12,16-olide ( 1 ) and 6'-acetoxypterolobirin B ( 3 ), together with a known analogue, identified as 12α,14β-dihydroxycassa-13(15)-en-12,16-olide ( 2 ), were isolated from the fruits of Pterolobium macropterum . Compound 1 is a cassane diterpenoid with a Δ 11(12) double bond conjugated with an α,β-butenolide-type, whereas compound 3 is a dimeric caged cassane diterpenoid with unique 6/6/6/6/6/5/6/6/6 nonacyclic ring system. The structures of 1 and 3 were characterized by extensive spectroscopic analysis combined with computational ECD analyses. The α-glucosidase inhibitory activity of isolated compounds was evaluated, and compounds 1 and 3 showed significant α-glucosidase inhibitory activity with IC 50 values of 66 and 44 μM., (Copyright © 2023, Cheenpracha et al.)

A phytochemical investigation of the twig extract of Trivalvaria costata (Hook.f. & Thomson) I.M.Turner has identified ten undescribed dimeric aporphine alkaloids, trivalcostatines A-J, one undescribed isoquinoline alkaloid, trivalcostaisoquinoline, and four known aporphine alkaloids. Their structures were elucidated by detailed analysis of NMR and HRESITOFMS data. Three of the dimeric aporphine structures were confirmed by single crystal X-ray diffraction analysis. All of the dimeric aporphine alkaloids were isolated as mixtures of atropisomers. Several of them were resolved by chiral-phase HPLC and the absolute configurations of the pure atropisomers were assigned by calculated and experimental ECD analysis. Bidebilines A and B, heteropsine, and urabaine showed α-glucosidase inhibitory activities with IC 50 values in the range of 4.1-11 μM., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

A new geranylated xanthone, nigrolineaxanthone AA ( 1 ) together with 18 known compounds ( 2 - 19 ) were isolated from latex and twig extracts of Garcinia nigrolineata Planch. ex T. Anderson. Some of the isolated compounds were assessed for their antidiabetic activities and cytotoxicity against three cancer cell lines. Of these, compounds 12 (IC 50 value of 25.8 ± 0.2 µM), 16 (IC 50 value of 124.8 ± 0.7 µM), and 17 (IC 50 value of 44.4 ± 1.1 µM) exhibited the highest α -glucosidase inhibitory, α -amylase inhibitory, and glycation inhibition activities, respectively. Compound 11 showed glucose consumption and glucose uptake with IC 50 values of 14.2 ± 0.8 µM and 3.1-fold. Compound 10 displayed cytotoxic activity against colon cancer (SW480) with an IC 50 value of 4.3 ± 0.1 µM), while compound 2 showed cytotoxicity against leukemic cancer (K562) with IC 50 value of 4.4 ± 0.3 µM.

Gonioridleylactam ( 1 ), a new compound, is a unique dimeric aristolactam isolated from the EtOAc extract of the twigs of Goniothalamus ridleyi King. The structure of gonioridleylactam ( 1 ) consists of two different aristolactams linked together with two methylenedioxy bridges at C-3/C-3' and C-4/C-4', generating a ten-membered ring of [1,3,6,8]tetraoxecine. A new natural product, gonioridleyindole (3-hydroxymethyl-1-methyl-1 H -benz[ f ]indole-4,9-dione, 2 ), together with eight known compounds ( 3-10 ) were also isolated from this plant. Their structures were extensively characterized by spectroscopic methods and comparisons were made with the literature. Compounds 1-4 , 7 , and 9 were evaluated for their α -glucosidase inhibitory activity. Of these, 3,5-demethoxypiperolide ( 7 ) displayed the highest α -glucosidase inhibitory activity, with an IC 50 value of 1.25 µM.

The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a global public health crisis. The reduced efficacy of therapeutic monoclonal antibodies against emerging SARS-CoV-2 variants of concern (VOCs), such as omicron BA.5 subvariants, has underlined the need to explore a novel spectrum of antivirals that are effective against existing and evolving SARS-CoV-2 VOCs. To address the need for novel therapeutic options, we applied cell-based high-content screening to a library of natural products (NPs) obtained from plants, fungi, bacteria, and marine sponges, which represent a considerable diversity of chemical scaffolds. The antiviral effect of 373 NPs was evaluated using the mNeonGreen (mNG) reporter SARS-CoV-2 virus in a lung epithelial cell line (Calu-3). The screening identified 26 NPs with half-maximal effective concentrations (EC 50 ) below 50 μM against mNG-SARS-CoV-2; 16 of these had EC 50 values below 10 μM and three NPs (holyrine A, alotaketal C, and bafilomycin D) had EC 50 values in the nanomolar range. We demonstrated the pan-SARS-CoV-2 activity of these three lead antivirals against SARS-CoV-2 highly transmissible Omicron subvariants (BA.5, BA.2 and BA.1) and highly pathogenic Delta VOCs in human Calu-3 lung cells. Notably, holyrine A, alotaketal C, and bafilomycin D, are potent nanomolar inhibitors of SARS-CoV-2 Omicron subvariants BA.5 and BA.2. The pan-SARS-CoV-2 activity of alotaketal C [protein kinase C (PKC) activator] and bafilomycin D (V-ATPase inhibitor) suggest that these two NPs are acting as host-directed antivirals (HDAs). Future research should explore whether PKC regulation impacts human susceptibility to and the severity of SARS-CoV-2 infection, and it should confirm the important role of human V-ATPase in the VOC lifecycle. Interestingly, we observed a synergistic action of bafilomycin D and N-0385 (a highly potent inhibitor of human TMPRSS2 protease) against Omicron subvariant BA.2 in human Calu-3 lung cells, which suggests that these two highly potent HDAs are targeting two different mechanisms of SARS-CoV-2 entry. Overall, our study provides insight into the potential of NPs with highly diverse chemical structures as valuable inspirational starting points for developing pan-SARS-CoV-2 therapeutics and for unravelling potential host factors and pathways regulating SARS-CoV-2 VOC infection including emerging omicron BA.5 subvariants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Farnesoid X receptor (FXR), a member of the nuclear receptor superfamily, plays an important role in maintaining or reversing metabolic homeostasis during the development of liver diseases. However, developing FXR modulators to intervene in FXR-related diseases is still an unmet clinical need. Therefore, it is significant to develop novel small-molecule agonists for drug discovery targeting FXR. Through a high-throughput chemical screen and follow-up biological validations, we first identified the natural product Fargesone A (FA) as a potent and selective FXR agonist. The limited, variable supply of FA from natural product isolation, however, has impeded its biological exploration and potential drug development. Accordingly, we have developed a biomimetic and scalable total synthesis of FA in nine steps that provides a solution to the supply of FA. Enabled by chemical synthesis, the in vivo efficacy of FA has been further investigated. The results showed that FA alleviates hepatocyte lipid accumulation and cell death in an FXR-dependent manner. Moreover, treatment of bile duct ligation (BDL)-induced liver disorder with FA ameliorates pathological features in mice. Therefore, our work lays the foundation to develop new small-molecule FXR agonists as a potential therapy for liver diseases., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Three new furanoxanthones, macochinxanthones A-C ( 1 - 3 ) and sixteen known xanthones ( 4 - 19 ) were isolated from the roots of Maclura cochinchinensis. Their structures were elucidated by spectroscopic analysis including NMR, UV and IR, as well as mass spectrometry. Chiral-phase HPLC analysis of 1 - 3 revealed that they were scalemic mixtures with an enantiomeric excess (ee) of 0.05%, 36.8% and 8%, respectively. Most of the isolated xanthones exhibited potent cytotoxicity against four cancer cell lines (KB, HelaS3, A549 and HepG2) with IC 50 values in the range of 1.29-90.15  µ M. In addition, many of them displayed antibacterial activity against Gram-positive bacteria and Methicillin resistant Stephylococus aureus (MRSA) with MIC values in the range of 4-128  µ g/mL.

A new C -benzylated flavone, uvariaruflavone ( 1 ), along with 13 known compounds ( 2 - 14 ) were isolated from the twig and leaf extracts of Uvaria rufa Blume. Their structures were established by extensive spectroscopic methods. Flavones ( 5 - 8 ) and cyclohexene ( 10 ) were isolated from U. rufa for the first time. Most of the isolated compounds were evaluated for their α -glucosidase and α -amylase inhibitory activities. Of these, uvariaruflavone ( 1 ) showed the highest α -glucosidase inhibitory activity with an IC 50 value of 44.3 µM, while ferrudiol ( 12 ) displayed the highest α -amylase inhibitory activity with an IC 50 value of 73.5 µM.

Phytochemical investigations of the leaf and pod extracts of Millettia brandisiana Kurz led to the isolation and identification of four previously undescribed rotenoids, (-)-(6aS,12aS)-millettiabrandisins A-C and (-)-(6aS,12aS)-6-deoxyclitoriacetal, two previously undescribed isoflavones, millettiabrandisins D and E, and 20 known compounds. The structures of previously undescribed compounds were determined on the basis of NMR and MS data. The absolute configurations of (-)-(6aS,12aS)-millettiabrandisins A-C were determined from the comparison of their experimental and calculated ECD spectra. (-)-(6aR,12aR)-12a-Hydroxy-α-toxicarol was also confirmed by X-ray crystallographic data. Some isolated compounds were evaluated for their cytotoxicity against three cancer cell lines, including lung cancer (A549), colorectal cancer (SW480), and leukemic cells (K562). Of these, α-toxicarol displayed the best cytotoxicity against lung cancer (A549) and leukemic cells (K562) with the IC 50 values of 104.4 and 67.5 μM, respectively. 6″,6″-Dimethylchromene-[2″,3″:7,8]-flavone showed the highest cytotoxicity against colorectal cancer (SW480) with an IC 50 value of 97.2 μM., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Three new isoflavonoids, millexatins N-P (1-3), along with seven known compounds (6-10), were isolated from the acetone extract of the young twigs of Millettia extensa . The structures were characterized by NMR spectroscopic and mass spectrometric analyses. Millexatin N (1) is an unusual geminal diisoprenylated isoflavone with a modified ring A. Millexatin P (3) is an unusual isoflavone with a cyclohexyl substituent on ring B, which is extremely rare in nature. The isolated metabolites (1, 2, and 6-10) were evaluated for cytotoxicities against MDA-MB231, Huh-7, KKU-100 and normal human dermal fibroblast (NHDF) cell lines. Only compounds 1, 6 and 8 showed cytotoxicities against all cell lines with IC 50 values ranging from 13.9 to 30.9 μM., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Kaempferia parviflora (Black ginger) is used widely in medical fields as an anti-microorganism and anti-inflammation. In this study, the aim was to evaluate the in vitro and in vivo anti-acne efficacy of black ginger extract. The results indicate that the methanol and ethanol extracts showed the highest total phenolic contents, without a significant difference, whereas the n -hexane extract showed the highest total flavonoid content. Nine flavones were detected using UPLC-QTOF-MS, and the ethyl acetate extract showed the highest amount of 5,7-dimethoxyflavone (DMF) according to HPLC. Antibacterial activity against Staphylococcus aureus , S. epidermidis , and Cutibacterium acnes was observed. All the extracts showed antimicrobial activity against C. acnes, revealing MICs in the range of 0.015 to 0.030 mg/mL, whereas the ethyl acetate extract inhibited the growth of S. epidermidis with a MIC of 3.84 mg/mL. In addition, the ethyl acetate extract showed the highest activity regarding nitric oxide inhibition (IC50 = 12.59 ± 0.35 µg/mL). The ethyl acetate extract was shown to be safe regarding cell viability at 0.1 mg/mL. The anti-acne efficacy was evaluated on volunteers. The volunteers were treated in two groups: one administered a 0.02% ethyl acetate extract gel-cream (n = 9) and one administered a placebo (n = 9) for 6 weeks. The group treated with the gel-cream containing the extract showed 36.52 and 52.20% decreases in acne severity index (ASI) after 4 and 6 weeks, respectively, and 18.19 and 18.54% decreases in erythema, respectively. The results suggest that K. parviflora could be a potent active ingredient in anti-inflammatory and anti-acne products.

A phytochemical investigation of the root and leaf extracts of Millettia pachycarpa Benth resulted in the isolation and identification of 16 compounds, including six rotenoids ( 1 - 6 ) and 10 prenylated isoflavonoids ( 7 - 16 ). Compound 4 was isolated as a scalemic mixture, which was resolved by chiral HPLC to afford (-)-(6a S ,12a S )-12a-hydroxy-α-toxicarol ( 4 ) and (+)-(6a R ,12a R )-12a-hydroxy-α-toxicarol ( 4 ). (+)-(6a R ,12a R )-Millettiapachycarpin ( 3 ) and (-)-(6a S ,12a S )-12a-hydroxy-α-toxicarol ( 4 ) were isolated as new compounds. The absolute configuration of (-)-(6 R )-pachycarotenoid ( 2 ), (+)-(6a R ,12a R )-millettiapachycarpin ( 3 ), (-)-(6a S ,12a S )- 4 and (+)-(6a R ,12a R )-12a-hydroxy-α-toxicarol ( 4 ), (+)-(6a S ,12a S )-( 5 ), and (-)-(6a S ,12a S ,2″ R )-sumatrol ( 6 ) were identified by electronic circular dichroism (ECD) data. (-)-(6a S ,12a S ,2″ R )-Sumatrol ( 6 ) was also confirmed by X-ray diffraction analysis using Cu-Kα radiation. Antidiabetic activities, including α-glucosidase and α-amylase inhibitory activities, and cytotoxicities against lung cancer A549, colorectal cancer SW480, and leukemic K562 cells of some isolated compounds were evaluated. Of these, isolupalbigenin ( 11 ) exhibited the highest α-glucosidase inhibitory activity, with an IC 50 value of 11.3 ± 0.2 μM, whereas the scalemic mixture of 12a-hydroxy-α-toxicarol ( 4 ) displayed the best α-amylase inhibitory activity, with an IC 50 value of 106.9 ± 0.2 μM. Euchrenone b10 ( 15 ) exhibited the highest cytotoxicity against lung cancer A549, colorectal cancer SW480, and leukemic K562 cells, with IC 50 values of 40.3, 39.1, and 15.1 μM, respectively. In addition, molecular docking simulations of α-glucosidase inhibition of the active compounds were studied., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Three previously undescribed isoflavones, derrisrobustones A-C, and a previously undescribed natural isoflavone, derrisrobustone D, along with eight known isoflavones, were isolated from the twig extract of Derris robusta (DC.) Benth. All structures were identified by extensive spectroscopic analysis. Derrisrobustones A-C were obtained as scalemic mixtures and were resolved by chiral HPLC. The (1″R, 2″R) absolute configuration of (+)-derrisrobustone B was established by single-crystal X-ray crystallography using Cu Kα radiation. The absolute configurations of derrisrobustones A and C were determined by analysis of experimental and calculated ECD data. All compounds were evaluated for their α-glucosidase inhibitory activity. Of these, derrubone displayed the best α-glucosidase inhibitory activity with an IC 50 value of 64.2 μM., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

A new clerodane diterpene, 2 β -methoxyhardwickiic acid ( 1 ), and four known compounds ( 2-5 ) were isolated from the twigs of Monoon membranifolium. The structure of the new compound was determined by extensive spectroscopic methods and ESITOFMS data. The absolute configuration of 1 was established by a comparison of its ECD spectrum and specific rotation with those of related previously reported compounds. All compounds were evaluated for their nitric oxide (NO) production inhibitory activities in RAW264.7 macrophage cells. Compounds 3 and 5 inhibited NO production with IC 50 values of 16.1 and 28.9 μM, respectively, which were better than that of standard compound, indomethacin (IC 50 = 32.2 μM).

The first investigation of Phyllanthus mirabilis Müll.Arg. led to the isolation of six undescribed compounds including two tyramine derivatives: phyllatyramines A and B; three butenolide analogues, phyllantenolide, phyllantenocoside-O-gallate and epi-phyllantenocoside-O-gallate; and a flavanonol gallate, (-)-taxifolin-3-O-gallate; as well as two first isolated natural products, phyllatyramine C and phyllantenocoside; together with twenty-three known compounds. Their structures were elucidated by spectroscopic means. ECD spectra of all isolated butenolides were compared and assigned the configurations. Phyllatyramine A displayed weak cytotoxicity against the KB cell line, while phyllatyramines B and C showed weak cytotoxicity against KB and HeLa cell lines. In addition, phyllatyramine B and (-)-taxifolin-3-O-gallate showed more potent α-glucosidase inhibitory activity than the standard acarbose 3.4 and 5.8 fold, respectively., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Chromatographic separation of crude extracts from the leaves and stems of Croton poomae Esser led to the isolation of two new clerodane diterpenes crotonolide K ( 1 ) and furocrotinsulolide A acetate ( 2 ) and six known clerodane diterpenes ( 3-8 ), together with twelve known compounds ( 9 - 20 ). Their structures were established from spectroscopic analysis. The clerodane diterpenoids 1 - 8 were evaluated for inhibition of nitric oxide (NO) production in LPS-activated RAW 264.7 macrophages. Compounds 1 , 2 , 5 , 7 and 8 showed potent inhibitory effects, with IC 50 values ranging from 32.19 to 48.85 μM, which is better than both the standard drugs indomethacin (154.5 μM) and dexamethasone (56.28 μM).

The phytochemical investigation of the fruit and leaf extracts of Maclura cochinchinensis (Lour.) Corner (Moraceae) resulted in the isolation and identification of four undescribed isoflavones (macluracochinones A-D) and one undescribed flavone (macluracochinone E), together with 24 known compounds. The structures of the undescribed compounds were elucidated using nuclear magnetic resonance (NMR) and high-resolution electrospray ionization time-of-flight mass spectrometry (HRESITOFMS) experiments. Gancaonin M, lupiwighteone, lupalbigenin, warangalone, auriculatin, and millexatin F displayed good antibacterial activities against Gram-positive bacteria with MIC values in the range of 1-8 μg/mL. Lupalbigenin showed strong activities against methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus with the same MIC value of 1 μg/mL., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Chemical investigation of the mycelia of the pathogenic fungus Curvularia sp. which was isolated from a leaf of Dactyloctenium aegyptium (crowfoot grass), resulted in the isolation of a new compound, curvulariahawadride (5), along with five known compounds (1-4, and 6). Their structures were determined on the basis of spectroscopic data, including 1D and 2D NMR and HRESIMS. The absolute configuration of 5 was established from experimental and calculated electronic circular dichroism (ECD). Compounds 1, 3, and 5 showed nitric oxide (NO) production inhibitory activity with IC 50 values of 53.7, 32.8, and 12.8 µM, respectively. Compounds 2 and 4 showed significant cytotoxicity against lung cancer A549, colorectal cancer SW480, and leukemic K562 cells with an IC 50 ranging value of 11.73 to 17.59 µM.

Daldiniaeschsone A ( 1 ), a rare tricyclic polyketide having a chromone unit fused to a δ -lactone and its symmetrical 6,6'-biphenyl dimer, daldiniaeschsone B ( 2 ), together with three known compounds ( 3 - 5 ), were isolated from a plant-derived endophytic fungus, Daldinia eschscholtzii SDBR-CMUNKC745. Their structures were elucidated by extensive 1D and 2D NMR spectroscopic data and HRESIMS. All compounds showed α -glucosidase inhibitory activity with IC 50 values ranging from 0.16-0.85 mM and compound 1 was the best α -glucosidase inhibitory activity (IC 50 = 0.16 mM).

The phytochemical investigation of the twig and root extracts of Erythrina subumbrans (Hassk.) Merr. (Fabaceae) resulted in the isolation and identification of a new pterocarpan, erythrinocarpan ( 1 ), along with 27 known compounds ( 2 - 28 ). All isolated compounds were evaluated for their antidiabetic, antimicrobial, and anti-inflammatory properties. Compounds 3 , 8 , 9 , and 22 had α-glucosidase inhibitory activity with IC 50 values of 13.4 ± 0.05, 24.5 ± 0.13, 29.0 ± 0.05, and 12.8 ± 0.14 μM, respectively, while compound 2 inhibited α-amylase activity with an IC 50 value of 67.6 ± 1.12 μM. Compounds 22 and 24 inhibited glycation activity with the IC 50 values of 36.9 ± 0.62 and 40.5 ± 0.37 μM, respectively. From cell-based assays, compound 27 showed the highest ability to induce glucose consumption (IC 50 29.1 ± 0.86 μM) and glucose uptake (2.8-fold), and to inhibit nitric oxide (NO) production (IC 50 52.5 ± 0.56 μM) without cell toxicity. Furthermore, compound 9 showed antimicrobial activities against Gram-positive bacteria and fungi with MIC values ranging from 2-4 μg/mL., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

Four new compounds, (+)-(2 S )-desmosdumosone ( 1 ), (+)-(2 R )-7,8-dimethoxy-5-hydroxyflavanone ( 7 ), (+)-(2 R )-7-methoxychamanetin ( 9 ), and (+)-(1' R ,2' R )-phebalosin ( 18 ), and 25 known compounds were isolated from the twig and leaf extracts of Desmos dumosus . Compounds (±)- 7 and (±)- 9 were isolated as racemates and their enantiomers were separated by chiral HPLC. Their structures were elucidated by spectroscopic methods as well as comparisons made from the literature. The absolute configuration of (+)-(1' R ,2' R )- 18 was established by X-ray diffraction analysis using Cu K α radiation and electronic circular dichroism (ECD) spectoscopy. In contrast, the absolute configuration of compounds (+)-(2 S )- 1 , (+)-(2 R )- 7 , and (+)-(2 R )- 9 were identified by comparing their ECD spectra and specific rotations with those of reported known compounds. Compounds 9 , 11 , 13 , 14 , 22 , 25 , and 28 showed α -glucosidase inhibitory activities with IC 50 values ranging from 5.3-52.7 μM, much better than that of standard control (acarbose, IC 50 value 83.5 μM). Compound 13 was the most active with an IC 50 value of 5.3 μM., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

The structure of the natural product lawinal [systematic name: (-)-(2 S )-5,7-dihy-droxy-6-methyl-4-oxo-2-phenyl-chromane-8-carbaldehyde, C 17 H 14 O 5 ] at 150 K is reported. The compound crystallizes with monoclinic ( I 2) symmetry and with Z ' = 2. The absolute configuration could not be determined reliably from X-ray analysis only. However, our analysis returns the S -configuration at the C-2 position, consistent with previous stereochemical assignment from specific rotation. The independent mol-ecules form into alternating hydrogen-bonded chains with C-H⋯O=CH inter-molecular linkages that run parallel to the crystallographic a axis and are extended into the ac plane by π-π inter-actions between their phenyl substituents., (© Suthiphasilp et al. 2021.)

Phytochemical investigations from the flower and leaf extracts of D. cochinchinensis resulted in the isolation and structural elucidation of five new polyoxygenated seco -cyclohexene derivatives, desmoscochinchinenes A-E ( 1 - 5 ), together with 11 known compounds ( 6 - 16 ). The structures on the new compounds were elucidated from their spectroscopic data, including UV, IR, NMR, and HRESITOFMS. Some of the isolated compounds were evaluated for their α -glucosidase inhibitory activities. Chrysin ( 9 ), pinocembrin 7- O -benzoate ( 12 ), and (-)-(5 R )-desmoscochinoxepinone B ( 16 ) inhibited α -glucosidase better than the standard control (acarbose, IC 50 = 83.5 μM) with IC 50 values of 5.7, 33.8, 53.3 μM, respectively., Competing Interests: The authors declare no conflict of interest., (© 2020 The Author(s).)

Two rare flavones having a hybrid benzyl benzoate ester-flavone structural framework, desmoschinensisflavones A and B (1 and 2), together with 12 known compounds (3-14) were isolated from the fruit, leaf, and twig extracts of Desmos chinensis (red flower). The new structures were characterized by UV, IR, NMR, and HRESITOFMS data. Desmoschinensisflavones A and B have a distinctive skeleton of benzoate ester-flavones with a C-4'' and C-6 and C-8 connection via a methylene group, respectively. Plausible biosynthesis pathways to compounds 1 and 2 are proposed based on an intermolecular nucleophilic 1,4-addition to ortho -quinone intermediates. Compounds 6-8 and 12 showed weakly antioxidant inhibition with IC 50 values in the range of 65.4-74.6 μM., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The structure of the racemic version of the natural product Goniotamirenone C [racemic anti -6-(2-chloro-1-hy-droxy-2-phenyl-eth-yl)-2 H -pyran-2-one, C 13 H 11 ClO 3 ] at 150 K is reported. The compound crystallizes with monoclinic ( P 2 1 / n ) symmetry and with Z ' = 2. One independent mol-ecule is ordered while the other independent mol-ecule exhibits an inter-esting whole-mol-ecule enanti-omeric disorder with occupancies of 0.846 (4) and 0.154 (4). The independent mol-ecules are hydrogen bonded with -OH⋯O=C linkages into chains that run parallel to the a axis. This structural analysis corrects our previous assignment as the syn isomer [Meesakul et al. (2020 ▸). Phytochemistry , 171 , 112248-112255]., (© Meesakul et al. 2020.)

The phytochemical investigation of the leaf extracts of Uvaria hamiltonii (Annonaceae) led to the isolation and identification of ten compounds including a new seco -cyclohexene ( 1 ) together with nine known compounds ( 2 - 10 ). Their structures were elucidated by intensive analysis by spectroscopic methods and comparisons of their spectroscopic data with those of compounds reported in the literature. Compounds 2 , 8 , and 9 showed potent α -glucosidase inhibitory activity with the IC 50 values ranging from 2.6-7.1  µ M.

Three undescribed spirosteroids, asparacemosones A-C, an undescribed spiro-21-norsteroid, asparacemosone D, along with seven known compounds were isolated from Thai herbal plant Asparagus racemosus Willd. roots. Their structures were elucidated by spectroscopic analysis including NMR, UV, IR and mass spectrometry. The absolute configurations of asparacemosones A, B, and D were determined by single crystal X-ray diffraction using CuKα radiation. Among the isolated compounds, the norlignan nyasol and three acetylenic norlignans demonstrated potent α-glucosidase inhibition, with IC 50 values ranging from 0.003 to 0.004 μM which is 5 × 10 4 fold more potent than the standard acarbose., (Copyright © 2020 Elsevier Ltd. All rights reserved.)