Search

The genus Curcuma is part of the Zingiberaceae family, and many Curcuma species have been used as traditional medicine and cosmetics in Thailand. To find new cosmeceutical ingredients, the in vitro anti-inflammatory, anti-oxidant, and cytotoxic activities of four Curcuma species as well as the isolation of compounds from the most active crude extract ( C. aromatica ) were investigated. The crude extract of C. aromatica showed 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity with an IC 50 value of 102.3 μg/mL. The cytotoxicity effect of C. aeruginosa, C. comosa, C. aromatica, and C. longa extracts assessed with the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay at 200 μg/mL were 12.1 2.9, 14.4 4.1, 28.6 4.1, and 46.9 8.6, respectively. C. aeruginosa and C. comosa presented apoptosis cells (57.7 3.1% and 32.6 2.2%, respectively) using the CytoTox-ONE™ assay. Different crude extracts or phytochemicals purified from C. aromatica were evaluated for their anti-inflammatory properties. The crude extract of C. aromatica showed the highest potential to inhibit NF-κB activity, followed by C. aeruginosa, C. comosa, and C. longa , respectively. Among the various purified phytochemicals curcumin, germacrone, curdione, zederone, and curcumenol significantly inhibited NF-κB activation in tumor necrosis factor (TNF) stimulated HaCaT keratinocytes. Of all compounds, curcumin was the most potent anti-inflammatory., Competing Interests: The authors declare no conflicts of interest.

The first phytochemical investigation of Polyalthia cinnamomea led to the isolation and identification of two new oxoprotoberberine alkaloids, (-)-(13aS)-polyalthiacinnamines A and B, together with eleven known compounds. The structures of the new compounds were elucidated by extensive spectroscopic methods. The absolute configuration of miliusacunine E and consanguine B was established by X-ray diffraction analysis using Cu Kα radiation and ECD spectra, whereas the absolute configurations of polyalthiacinnamines A and B were established by comparison of their ECD spectra and specific rotations with those of miliusacunine E and consanguine B. Compounds 1-4, 6, and 8 exhibited α-glucosidase inhibitory activities (IC 50 values ranging from 11.3 to 57.9 µM) better than a positive control (acarbose, IC 50 83.5 μM). Compound 2 also exhibited NO production inhibitory activity with an IC 50 value of 24.4 μM (indomethacin, a positive control, IC 50  = 32.2 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 © 2020 Elsevier Ltd. All rights reserved.)

Garcinia cowa Roxb. ex Choisy (Clusiaceae) is a Thai local edible plant, which has been used for the treatment of diabetes. The aim of this study is to discover and identify bioactive compounds related to antidiabetic properties from the leaf extract of G. cowa . α -Glucosidase inhibitory bioassay-guided isolation of the ethyl acetate extract of the leaves of G.cowa resulted in the isolation and identification of 11 compounds. Of these, a decahydro-1 H -xanthene derivative, garciniacowone K ( 1 ), was identified as a novel compound. Their structures were characterized by spectroscopic data and by comparison of their NMR spectroscopic data with those previously reported. All compounds were evaluated for their α -glucosidase inhibitory and glucose consumption activities. Compound 2 showed the highest efficacy in inhibiting α -glucosidase enzyme and promoting glucose consumption activity by 3T3-L1 cells, with IC 50 values of 0.5 μM and 13.1 μM, respectively, without causing toxicity to cells., (© 2020 The Authors.)

The phytochemical investigation of the twig and leaf extracts of Goniothalamus tamirensis led to the isolation and identification of 15 compounds including three rare previously undescribed styryllactones, goniotamirenones A-C, together with 12 known compounds. (Z)-6-Styryl-5,6-dihydro-2-pyranone and 5-(1-hydroxy-3-phenyl-allyl)-dihydro-furan-2-one are reported here for the first time as previously undescribed natural products. Their structures were elucidated by spectroscopic methods. Goniotamirenone A was synthesized via a [2 + 2] cycloaddition reaction of 6-styrrylpyran-2-one in quantitative yield. The absolute configurations of goniotamirenones B and C were identified from experimental and calculated ECD data, while the absolute configurations of (-)-5-acetoxygoniothalamin, (-)-isoaltholactone, parvistone E, and 5-(1-hydroxy-3-phenyl-allyl)-dihydro-furan-2-one were identified by single-crystal X-ray diffraction analysis using Cu Kα radiation. The absolute configurations of the other related compounds were determined from comparisons of their ECD spectra with relevant compounds reported in the literature. (-)-5-Acetoxygoniothalamin exhibited potent cytotoxicity against the colon cancer cell line (HCT116) with an IC 50 value of 8.6 μM which was better than the standard control (doxorubicin, IC 50  = 9.7 μM), while (Z)-6-styryl-5,6-dihydro-2-pyranone was less active with an IC 50 value of 22.1 μM., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The essential oils of the fresh rhizomes; flowers; and leaves of Zingiber kerrii Craib were investigated using different extraction techniques; including solid-phase microextraction (SPME), hydrodistillation (HD), and organic solvent (OS), and characterized by gas chromatography-mass spectrometry (GC-MS). A total of 37 SPME; 19 HD; and 36 OS compounds were identified from the rhizome extract of Z. kerrii; with the major components being α-pinene; β-pinene; and terpinen-4-ol; respectively. From the flower extract; 16 SPME; 2 HD; and 10 OS compounds were identified; ( E )-caryophyllene was found as a major compound by these techniques. The leaf extract exhibited 20 SPME; 13 HD; and 14 OS compounds; with α-pinene; ( E )-caryophyllene; and n -hexadecanoic acid being the major compounds; respectively. The rhizome extract showed tyrosinase inhibitory activity of 71.60% and a total phenolic content of 22.4 mg gallic acid/g. The IC 50 values of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays were 25.2 µg/mL and 153.6 µg/mL; respectively; and the ferric ion reducing antioxidant power (FRAP) assay value was 318.5 µM ascorbic acid equivalent (AAE)/g extract. The rhizome extract showed weak antibacterial activity. This extract showed no adverse toxicity in human keratinocyte (HaCaT) cell lines at concentrations below 200 µg/mL.

Five new compounds-two phloroglucinol benzophenones, garciniacowones F ( 1 ) and G ( 2 ), and three xanthones, garciniacowones H ( 3 ), I ( 4 ), and J ( 5 )-together with seven known xanthones ( 6 - 12 ) were isolated from the fresh leaves of Garcinia cowa . Their structures were elucidated by detailed analysis of NMR and MS data. Compounds 1 and 2 are phloroglucinol benzophenones containing a polyprenylated bicyclo[3.3.1]nonane ring system, while compounds 3 - 5 are rare xanthones having farnesyl ( 3 and 5 ) and geranylgeranyl ( 5 ) units at C-8. Compounds 1 , 3 , 4 , 7 , 8 , and 10 exhibited inhibitory effects on NO production in LPS-induced RAW264.7 macrophage cells with IC 50 values ranging from 5.4 to 18.6 μM. Compounds 4 and 8 had α-glucosidase inhibitory activities with IC 50 values of 15.4 and 11.4 μM, respectively, which were more potent than that of the acarbose control.

Five new aristolactam alkaloids ( 1 - 5 ), dasymaschalolactams A-E, and the first isolation of dasymaschalolactone ( 17 ) as a natural product, together with 19 known compounds ( 6 - 16 and 18 - 25 ) were isolated from the twig extract of Dasymaschalon dasymaschalum . Their structures were elucidated by spectroscopic methods as well as comparisons made from the literature. Compounds 20 and 21 showed α-glucosidase inhibitory activities with IC 50 values of 4.5 and 24.7 μM, respectively.

The first phytochemical investigation of Uvaria lurida resulted in the isolation and identification of three new polyoxygenated cyclohexenes, (+)-(1R,2S,3R,6S)-uvarialuridols A-C (1-3), together with 10 known compounds (4-13). All new structures were elucidated by spectroscopic methods and HRESIMS. The absolute configurations of compounds 1 and 5 were confirmed by X-ray diffraction analysis using Cu Kα radiation. The absolute configurations of compounds 2-4 were identified from comparisons of their specific rotations and ECD spectra with those of known compounds. Compound 11 showed α-glucosidase inhibitory activity with an IC 50 value of 30 μM which was better than the standard control, acarbose (74 μM) whereas, compound 10 exhibited nitric oxide (NO) production inhibitory activity with an IC 50 value of 37 μM., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A phytochemical investigation of the fruit and root extracts of Micromelum integerrimum resulted in the isolation and identification of a new compound, integerravone ( 1 ), together with 23 known compounds ( 2 - 24 ). Their structures were characterized by spectroscopic methods as well as comparisons made from the literature. Compounds 2 , 3 - 15 , 17 - 18 and 20 - 23 were evaluated for their cytotoxicities against the colon cancer cell line, HCT116. All of them were inactive at 50  µ M. Most of the phenolic compounds were evaluated for their antioxidant activity using the DPPH assay. Compounds 14 and 22 - 24 showed antioxidant activity with IC 50 values ranging from 24.83-135.05  µ M.

The chromatographic separation of the components of the acetone extract of Mallotus philippensis fruits yielded five new phenolic compounds including two chalcones, 1 and 3 , a functionalized phloroglucinol, 2 , two flavanones, 4 and 5 , and six known compounds. The structures of 1 - 5 were confirmed by NMR and mass analyses. Racemic compounds 1 and 2 were separated by chiral-phase HPLC, and the absolute configuration of (+)- 1 was confirmed by X-ray diffraction studies and ECD spectroscopic data. The configurations of the enantiomers of 2 were defined by comparison of its ECD data with those of (+)- 1 . Compounds 6 and 7 exhibited significant antibacterial activities, with MIC values ranging from 3.8 to 15.5 μM.

A chemical investigation of leaf and root extracts of Millettia extensa led to the isolation and structural elucidation of four new prenylated isoflavones, millexatins G-J ( 1 - 4 ), and three new coumaronochromones, millexatins K-M ( 5 - 7 ), along with 16 known compounds. The structures of the new compounds were determined on the basis of NMR and MS data. Compound 4 is a rare isoflavone having a 2-hydroxyethyl moiety at C-8, whereas the structures of compounds 5 - 7 formally arise from a ring closure through HO-2' and C-2. The absolute configurations at the C-2 and C-3 positions of 5 and 6 were determined from their ECD spectra through comparison with those of previously reported compounds. Most of compounds were evaluated for their inhibitory effects against nitric oxide (NO) production on RAW264.7 macrophages and their antibacterial activities. Compounds 18 and 19 inhibited NO production with IC 50 values of 8.5 and 14.3 μM, respectively. Compounds 13 and 14 showed antibacterial activity against various Gram-positive bacteria with MIC values ranging from 2 to 8 μg/mL.

Four new compounds (1-4) together with six known compounds (5-10) were isolated from the leaf extract of Garcinia nigrolineata. Compound 4 is a rare tocotrienol quinone dimer. The structures were elucidated based on NMR and MS data. All isolated compounds were evaluated for their antibacterial activities., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Four new flavonoids (1-4), a new benzyl benzoate derivative (5), five new oxepinones (6-10), and 14 known compounds (11-24) were isolated from the leaf and twig extracts of Desmos cochinchinensis. Their structures were established by spectroscopic methods. The structure of 1 was also confirmed by X-ray diffraction data. The absolute configurations of 3, 4, and 6-10 were determined from comparisons of their ECD spectra with those of relevant reported compounds. Compounds 1, 2, 6, 8, 10, 12-15, and 17 showed α-glucosidase inhibitory activities with IC 50 values ranging from 0.2 to 4.9 μM.

The phytochemical investigation of an alkaloidal extract of Holarrhena pubescens roots led to the isolation and identification of a new pregnene-type alkaloid, mokluangin D (1), together with nine known steroidal alkaloids (2-10). The structure of the new metabolite was determined on the basis of spectroscopic analyses including 1D- and 2D-NMR spectroscopy and mass spectrometry. Compounds 3 and 4 showed potent antimalarial activity against Plasmodium falciparum K1 stain with IC 50 values of 1.2 and 2.0 μM, respectively, and showed weak cytotoxic activity against the NCI-H187 cell line with IC 50 values of 27.7 and 30.6 μM, respectively. The substituent groups at C-3 and the carbonyl group at C-18 are important for the activity against the P. falciparum K1 stain.

Four new chalcones (1, 10, 13, and 14), a new flavanone, (9), a new amide (8), and 19 known compounds were acquired from Melodorum siamensis. The structures were established by NMR and MS data analyses. Compounds 1 (er 1.4:1) and 2 (er 1.1:1) were scalemic and were resolved to yield (-)-1 and (+)-1 and (-)-2 and (+)-2, respectively. The absolute configurations of these compounds were determined from experimental and calculated ECD data. The structures and configurations of (-)-2 and (+)-8 were identified by single-crystal X-ray diffraction analysis. Compound 11 showed nuclear factor-κB inhibitory effects (IC 50 = 9 μM) in a pancreatic β cell line (MIN-6 cells).

The chemical study of leaf extracts from Uvaria cherrevensis resulted in the identification of 11 new polyoxygenated cyclohexenes, cherrevenols A-K (1-11), and a new seco-cyclohexene derivative, cherrevenol L (12). Nine known compounds (13-21) were also isolated. Three of the isolated compounds are chlorinated polyoxygenated cyclohexenes. The structures of these compounds were determined using spectroscopic methods and, in some cases (compounds 2, 6, 8, and 10), single-crystal X-ray crystallographic structural analysis or chemical correlation (compounds 6 and 7). Compounds 6 and 7 were both isolated as scalemic mixtures (ee 23-24%).

Eight previously undescribed compounds, including four alkaloids and five styryllactones together with 36 known compounds were isolated from the twig and leaf extracts of Goniothalamus cheliensis. Their structures were elucidated by extensive analysis of their spectroscopic data. The absolute configuration of (-)-(4S,5S,6R,7S,8S)-goniochelienlactone and (-)-(4S,5S,6R,7S,8S)-7-acetylgoniochelienlactone were established from single crystal X-ray analysis using Cu Kα radiation. The absolute configurations of the other related compounds were identified by comparisons of their ECD spectra with those of related known compounds. Most of the isolated compounds were evaluated for their cytotoxicities against human colorectal cancer cells (HCT-116). Griffithazanone A was the most potent with an IC 50 value of 2.39 μM., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Biotransformation of β-mangostin (1) by the endophytic fungus Xylaria feejeensis GM06 afforded hexacyclic ring-fused xanthenes with an unprecedented hexacyclic heterocylic skeleton. β-Mangostin (1) was transformed to two diastereomeric pairs of enantiomers, mangostafeejin A [(-)-2a/(+)-2b)] and mangostafeejin B [(-)-3a/(+)-3b)]. The chemical structures of the transformation products were elucidated by analysis of NMR and MS data, and the structure of mangostafeejin A [(-)-2a/(+)-2b)] was confirmed by single-crystal X-ray diffraction analysis. The absolute configurations of 3a and 3b were established on the basis of calculated and measured ECD data using the ECD spectra of 2a and 2b as models. The fungal biotransformation described herein provides an effective method to convert an abundant achiral plant natural product scaffold into new chiral heterocyclic scaffolds representing expanded chemical diversity for biological activity screening.

The phytochemical investigation of the fruit extracts of Uvaria cherrevensis led to the isolation and characterization of four new C-benzyl flavonoids; cherrevenones A-D (1-4) together with 11 known compounds. The isolated compounds were characterized using spectroscopic techniques. Compounds 1, 3, 5 and 11 showed moderate inhibitory activities against the P. falciparum strains TM4/8.2 and K1CB1 with IC 50 values ranging from 21.0 ± 3.10 - 33.7 ± 7.69 and 21.0 ± 5.44 - 43.5 ± 11.9 μM, respectively. Compounds 1, 2, 5, 10 and 11 exhibited strong cytotoxic activities against KB cells with IC 50 values ranging from 0.60 ± 0.17 - 4.91 ± 2.69 μM which were similar to their cytotoxic activities found against Vero cells, except for compound 5, which was non-toxic to Vero cells., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Two new compounds, odoratisol E (1) and decurrenal A (2), together with 12 known compounds were isolated from the twig and leaf extracts of Mitrephora wangii HU (Annonaceae). All structures were elucidated by spectroscopic methods. The structure of compound (+)-6 was also confirmed by X-ray diffraction analysis. The absolute configurations of odoratisol E and decurrenal A were determined by comparison of their electronic circular dichroism (ECD) spectra with those of related known compounds. Most of the isolated compounds were evaluated for their antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. Compounds 4 and (+)-6 displayed potent ABTS radical scavenging activity with IC 50 values of 11.9 ± 1.8 and 10.8 ± 1.7 μM, respectively, which is better than that of standard compound, ascorbic acid, (IC 50  = 19.3 ± 0.1 μM). Compound 9 showed moderate DPPH radical scavenging activity with an IC 50 value of 38.7 ± 0.8 μM., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The first phytochemical investigation of the stem extract of Millettia extensa resulted in the isolation and identification of six new isoflavones, millexatins A-F (1-6), together with 16 known compounds. The structures of these new compounds were determined on the basis of their spectroscopic data. Millexatin A (1) is a rare isoflavone containing three isoprenyl units on a modified A ring. Compounds 1, 6, 10, 11, and 14 displayed promising antibacterial activity with MIC values of 2-8 μg/mL.

Colorectal cancer, which is the third most common type of cancer diagnosed in both men and women, is the leading cause of cancer-related deaths worldwide. Cowanin is a pure compound extracted from Garcinia cowa Roxb., a tree species present in Thailand, Malaysia and Myanmar. The crude extract has been demonstrated to have antitumor activity, inflammation induction, antibacterial activity, anti-inflammatory activity and antimalarial activity. In the present study, the effects of cowanin on apoptosis induction and on the apoptosis-related and mitogen-activated protein kinase (MAPK) pathways were investigated in the LoVo human colorectal cancer cell line. The cytotoxicity of cowanin in LoVo cells was determined by MTT assay. Hoechst 33342 and JC‑1 staining were used to determine nuclear morphological changes and mitochondrial membrane potential, respectively. The expression levels of BCL2 apoptosis regulator (Bcl‑2) family, MAPK and AKT serine/threonine kinase 1 (Akt) pathway proteins following cowanin treatment were determined by western blot analysis. The results demonstrated that cowanin inhibited cell proliferation and induced cell death via the apoptosis pathway. Cowanin treatment increased BCL2 associated X (Bax) and decreased Bcl‑2 expression. In addition, cowanin activated caspase‑9, -7 and poly-ADP-ribose-polymerase expression. Furthermore, cowanin decreased the levels of phosphorylated extracellular signal-regulated kinase (p‑ERK), p‑Akt, p‑3‑phosphoinositide‑dependent protein kinase‑1, while it increased p‑p38 expression, thus resulting in the induction of apoptosis. In conclusion, cowanin inhibited cell proliferation and induced apoptosis of LoVo cells via the MAPK and Akt signaling pathways. Notably, inhibition of p38 by using a p38 inhibitor (SB203580) prevented the cowanin-induced apoptosis in LoVo cells. These results suggested that cowanin may be a potential candidate for the treatment of colorectal cancer and provided important information on the molecular mechanisms underlying its antitumor activity.

A new scalemic 8,8a-dihydro caged xanthone (1) was isolated from the leaf extract of Garcinia propinqua. Five other known natural products, the three caged xanthones (2, 5 and 6) and the two neocaged xanthones, (3 and 4) were also isolated as scalemic mixtures. Their structures were characterized by spectroscopic methods. The enantiomeric ratios (er) of compounds 1-6 ranged from 1:0.7 to 1:0.9. These compounds were also resolved by semipreparative chiral HPLC. The absolute configurations of (+)-2 and (+)-3 were determined by single-crystal X-ray diffraction analysis using Cu Kα radiation while the absolute configurations of the other compounds were determined by comparisons of their ECD spectra. Compounds (-)-4, (+)-4, (-)-5, (+)-5, and (-)-6 showed potent cytotoxicities against a colon cancer cell line HCT116 with IC 50 values of 2.60, 7.02, 1.47, 3.37, and 4.14μM, respectively, which were better than the standard control doxorubicin (IC 50 9.74μM)., (Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.)

Two new polycyclic prenylated xanthones (1 and 2) and a new phenylpropanoid glycoside (3), along with seven known compounds (4-10) were isolated from the fruits of Garcinia xanthochymus. The structures were elucidated by 1D- and 2D-NMR, and HRMS experiments. The isolates were evaluated for their inhibitory effects against the viability of U251MG glioblastoma and MDA-MB-231 breast cancer cells that harbor an aberrantly active signal transducer and exhibit activation of transcription 3 (STAT3), and compared to normal NIH3T3 mouse fibroblasts. Among the isolates, compounds 1, 2, 5, and 6-9 inhibited the viability of glioma cancer cells with IC 50 values in the range of 1.6-6.5μM. Furthermore, treatment of U251MG with 6 and 7 inhibited intracellular STAT3 tyrosine phosphorylation and glioma cell migration in vitro, respectively., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Seven new caged xanthones, doitunggarcinones E-K (1-7), all as scalemic mixtures and 10 known compounds (8-17), were isolated from the stem bark extract of Garcinia propinqua. The structures were elucidated on the basis of spectroscopic methods. The separation of the enantiomers of 1-6 was achieved by semipreparative chiral HPLC. The absolute configuration of compound (+)-1 was determined by single-crystal X-ray crystallographic analysis using Cu Kα radiation. The absolute configurations of the other related compounds were determined from comparisons of their ECD spectra with that of compound (+)-1. Compounds (-)-6 and 7 showed cytotoxicity against a colon cancer cell line with IC 50 values of 14.23 and 23.95 μM, respectively.

Two new benzophenones (1 and 2) and four new xanthones (4-6 and 17) together with 24 known compounds (3, 7-16, and 18-30) were isolated from the roots and twigs of Cratoxylum sumatranum ssp. neriifolium. Their structures were elucidated by spectroscopic methods. Compounds 5 and 26 showed antibacterial activity against Micrococcus luteus, Bacillus cereus, and Staphylococcus epidermis with minimum inhibitory concentrations ranging from 4 to 8 μg/mL, whereas compounds 7, 20, and 26 displayed selective antibacterial activities against Staphylococcus aureus (8 μg/mL), Salmonella typhimurium (4 μg/mL), and Pseudomonas aeruginosa (4 μg/mL), respectively. The radical scavenging effects of some isolated compounds were investigated. Compounds 11 and 21 exhibited potent activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) with IC 50 values of 7.0 ± 1.0 and 6.0 ± 0.2 μM, respectively.

Bioassay-guided fractionation of the dichloromethane extract from the apical bud of Gardenia sootepenesis Hutch. (Rubiaceae) led to the isolation of four new cycloartane triterpenes, sootepins F-I (1-4), along with four known derivatives (5-8). The structures of the new compounds were determined by 1D and 2D NMR experiments and by comparison of the physicochemical data with published values. The isolates were evaluated for cancer chemopreventive potential based on their ability to inhibit nitric oxide (NO) production and tumor necrosis factor-alpha (TNF-α)-induced nuclear factor kappa (NF-κB) activity. Compounds 6-8 inhibited TNF-α-induced NF-κB activity with half maximal inhibitory concentration (IC 50 ) values of 8.3, 5.6, and 6.0μM, respectively; compounds 7 and 8 showed significant NO-inhibitory activity with IC 50 values of 3.2 and 2.0μM, respectively., (Copyright © 2016. Published by Elsevier B.V.)

Five new oxoprotoberberine alkaloids, miliusacunines A-E (1-5), along with nine known compounds, 6-14, were isolated from an acetone extract of the leaves and twigs of Miliusa cuneata. Their structures were elucidated by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicities against the KB and Vero cell lines and for antimalarial activities against the Plasmodium falciparum strains TM4 and K1 (a sensitive and a multi-drug-resistant strain, respectively). Compound 1 showed in vitro antimalarial activity against the TM4 strain, with an IC50 value of 19.3 ± 3.4 μM, and compound 2 demonstrated significant activity against the K1 strain, with an IC50 value of 10.8 ± 4.1 μM. Both compounds showed no discernible cytotoxicity to the Vero cell line at the concentration levels evaluated.

An alkaloidal extract of the bark of Holarrhena pubescens showed several inhibition zones of acetylcholinesterase (AChE) inhibitor, using a bioautographic assay. Activity-guided fractionation afforded three new steroidal alkaloids, mokluangins A-C (1-3), together with three known compounds, antidysentericine (4), holaphyllamine (5), methylholaphyllamine (6). All structures were elucidated by analysis of NMR and MS spectroscopic data. Compound 2 showed moderate antibacterial activity against Bacillus subtilis and Escherichia coli with the MIC value of 16 μg/mL, while compound 3 exhibited moderate selective activity against E. coli with the MIC value of 16 μg/mL. In addition, compounds 1-4 also showed strong AChE inhibiting activity with IC50 values ranging from 1.44 to 23.22 μM. Molecular docking calculations were also performed and the results demonstrated that all compounds can bind at the aromatic gorge of AChE with estimated binding free energies correlated well with the in vitro inhibitory profiles. Hydrophobic and hydrogen bonding interactions contribute mainly to the binding of the alkaloids where the substituents at C-3 serving as key functional groups for the AChE inhibition. Our results will allow the development of new AChE-inhibitors based on steroidal alkaloid skeleton bearing the cyclic amide moiety., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The first phytochemical investigation of Casearia graveolens twigs led to the isolation and identification of a new clerodane diterpene, caseariagraveolin (1), together with six known compounds (2-7). Their structures were elucidated by intensive analysis of their spectroscopic data. Compound 1 showed strong cytotoxicity against oral cavity and breast cancer cell lines with IC₅₀ values of 2.48 and 6.63 µM, respectively.

Phytochemical investigation of Garcinia propinqua roots led to the isolation and identification of a new xanthone, doitunggarcinone D (1), together with 15 known compounds (2-16). Their structures were elucidated by intensive analysis of spectroscopic data. Compounds 3, 6, 7, 14, 15 and 16 exhibited strong antibacterial activity against Bacillus subtilis TISTR 088 with MIC values in the range of 1-4 µg/mL. Compounds 3, 7, 10 and 14 also showed good antibacterial activity against B. cereus TISTR 688 with MIC values ranging from 4-8 µg/mL.

One new p-quinonoid aporphine alkaloid, obtusipetadione (1), and eleven known compounds (2-12) were isolated from the acetone extract of the twigs of Dasymaschalon obtusipetalum. Their structures were elucidated by spectroscopic methods. The cytotoxic and antimalarial activities of the isolated compounds were evaluated. Compound 1 showed significant in vitro antiplasmodial activity against the P. falciparum strains TM4 and K1 (multidrug resistant strain) with IC50 values of 2.46 ± 0.12 and 1.38 ± 0.99 μg/mL, respectively with no cytotoxicity. Compound 9 had more modest antiplasmodial activity, but significant cytotoxicity.

Five new xanthones, garciniacowones A-E (1-5), together with 14 known xanthones, 6-19, were isolated from the young fruits and fresh flowers of Garcinia cowa. The structures of 1-5 were elucidated by analysis of their 1D and 2D NMR spectra and mass spectrometric data. The compounds 1-19 were tested in vitro for their antimicrobial activity and for their ability to inhibit α-glucosidase. Compounds 16 and 17 showed the most potent α-glucosidase inhibitory activity, with IC50 values of 7.8 ± 0.5 and 8.7 ± 0.3 μM, respectively. Compounds 8, 9, and 19 showed antibacterial activity against Bacillus subtilis TISTR 088 with identical MIC values of 2 μg/mL, while 8, 10, and 19 exhibited antibacterial activity against Bacillus cereus TISTR 688 with identical MIC values of 4 μg/mL.

The first phytochemical investigation of Glycosmis puberula twigs led to the isolation and identification of a new quinolone alkaloid, glycosmispuberulone (1), along with ten known compounds (2-11). The structures were elucidated by spectroscopic analyses and comparison with previously reported data. Their antibacterial activities against Gram-positive and Gram-negative bacteria were also evaluated.

Phytochemical investigation of the roots of Cratoxylum formosum spp. pruniflolnnm led to the isolation and identification of a new xanthone, namely cratopruniforone (1), together with 13 known compounds (2-14). Some of these more abundant compounds were evaluated for their antibacterial activities.

The phytochemistry of Kopsia arborea Blume has received considerable attention, which has resulted in the isolation of a number of new unusual indole alkaloids with intriguing structures. In this study, a new eburnane-type alkaloid, phutdonginin (1), together with eight known alkaloids: 19-OH-(-)- eburnamonine (2), melodinine E (3), kopsinine (4), kopsilongine (5), kopsamine (6), (-)-methylenedioxy-1 1,12-kopsinaline (7), decarbomethoxykopsiline (8), and vincadifformine (9), were isolated from the twigs of K. arborea. Their structures were characterized extensively by 1D and 2D NMR spectroscopy and HR-ESI-MS. All compounds were submitted to TLC screening for acetylcholinesterase inhibitory activities. Only kopsamine and decarbomethoxykopsiline showed AChE inhibition with MIR values of 12.5 and 6.25 μg, respectively, compared with galanthamine (positive control, 0.004 μg). In addition, compounds 1 and 2 inhibited moderate antibacterial activity against E. coli TISTR 780 with the MIC value of 32 .g/mL.

Two new tetracyclo[7.3.3.3(3,11).0(3,7)]tetradecane-2,12,14-trione derivatives, cowabenzophenones A (1) and B (2), were isolated from ripe fruits of Garcinia cowa Roxb. Their structures were determined by spectroscopic methods. The tetracyclo[7.3.3.3(3,11).0(3,7)]tetradecane-2,12,14-trione skeleton from the Garcinia genus is reported for the first time., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Chemical investigation of an alkaloidal extract of Alstonia macrophylla bark led to the isolation and identification of two new nitrogenous derivatives, alstoniaphyllines A (1) and B (2), a new indole alkaloid, alstoniaphylline C (4), and eight known alkaloids (3, 5-11). Alstonisine (9) exhibited antiplasmodial activity against Plasmodium falciparum, with an IC50 of 7.6 μM.

Five carbazole alkaloids, clausenawallines G-K (1-5), along with 12 known alkaloids (6-17) were isolated from the twigs of Clausena wallichii. Their structures were established using spectroscopic methods and the antibacterial activity of compounds 1-5 was evaluated., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Two new compounds, garciniacowol (1) and garciniacowone (2) along with 15 knowncompounds were isolated from the stem barks of Garcinia cowa. Their structures weredetermined by intensive spectroscopic methods. The structure of 1 was a symmetrical dimericdihydrobenzopyran derivative, whereas the framework of 2 was a triprenyl caged-xanthoneprecursor. The antibacterial activities against Escherichia coli TISTR 780, Salmonellatyphimurium TISTR 292, Staphylococcus aureus TISTR 1466, and methicillin-resistant S. aureus(MRSA) SK1 of the isolated compounds were also evaluated. Compounds 2 and 9 exhibitedgood antibacterial activity against MRSA SK1 with the same minimum inhibitory concentration(MIC) value of 2 μg/mL. Moreover, compound 2 also showed good antibacterial activityagainst S. aureus with an MIC value of 2 μg/mL.

In the title compound, C17H16O7, which was isolated from the leaves of Micromelum integerrimum, the furan ring adopts an envelope conformation with the O atom as the flap. An intra-molecular C-H⋯O hydrogen bond occurs. The carbonyl O atom is disordered in a 0.57 (8):0.43 (8) ratio. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds into a C(10) chain along [010].

The first phytochemical investigation of Garcinia propinqua has led to the isolation and identification of three new compounds, including two rearranged benzophenones, doitunggarcinones A (1) and B (2), and a xanthone, doitunggarcinone C (3), together with seven known compounds (4-10). The structures of 1-3 were elucidated on the basis of spectroscopic methods, including UV, IR, NMR, and MS. The antibacterial activity of the 10 isolates was evaluated against Escherichia coli TISTR 780, Salmonella typhimurium TISTR 292, Staphylococcus aureus TISTR 1466, and methicillin-resistant Staphylococcus aureus (MRSA) SK1.

Three new carbazole alkaloids, harmandianamines A-C (1-3), together with fifteen known compounds (4-18) were isolated from the twigs of Clausena harmandiana. The structures were elucidated by spectroscopic methods, including UV, IR, NMR, and MS. The antibacterial activity against Escherichia coli TISTR 780, Salmonella typhimurium TISTR 292, Staphylococcus aureus TISTR 1466 and methicillin-resistant S. aureus (MRSA) SK1 of some isolated compounds was also evaluated. Compound 6 exhibited significant antibacterial activity against MRSA SK1 with an MIC value of 0.25 μg/mL which higher than that of standard drug, vancomycin (MIC value=1 μg/mL) whereas compounds 14 and 5 showed strong activity with MIC values of 4 and 8 μg/mL, respectively. Only compound 14 showed strong antibacterial activity against S. aureus TISTR 1466 with an MIC value of 4 μg/mL., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A new amide, zanthorhetsamide (1), along with nine known compounds (2-10) was isolated from the roots and stem barks of Zanthoxylum rhetsa. The structure was characterized by spectroscopic methods. In addition, the antibacterial activity of the isolates was evaluated. Dihydrochelerythrine (4) exhibited strong activity against methicillin-resistant Staphylococcus aureus SK1 and moderate activity against Escherichia coli TISTR 780 with MIC values of 8 and 16 μg/mL, respectively.

The title compound, C(33)H(42)O(5), known as xerophenone A {systematic name: (1R,3R,4R,6S,8E,10R)-10-hy-droxy-8-[hy-droxy(phen-yl)methyl-ene]-4-methyl-1,6-bis-(3-methyl-but-2-en-1-yl)-3-(3-methyl-but-3-en-1-yl)-11-oxatricyclo-[4.3.1.1(4,10)]undecane-7,9-dione} is a naturally occurring rearranged benzophenone compound which was isolated from the twigs of Garcinia propinqua. The absolute configuration was determined by refining the Flack parameter to 0.18 (16). The absolute configurations at positions 1, 3, 4, 6 and 10 of the xerophenone A are R, R, R, S and R. In the mol-ecule, the cyclo-hexane-1,3-dione, tetra-hydro-2H-pyran and tetra-hydro-furan rings adopt twisted boat, standard chair and envelope conformations, respectively. The 3-methyl-but-3-en-1-yl substituent is disordered over two sets of sites in a 0.771 (11):0.229 (11) ratio. An intra-molecular O-H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked by O-H⋯O and weak C-H⋯O inter-actions into a chain along the a axis. A very weak C-H⋯π inter-action and C⋯O short contact [2.989 (2) Å] are also present.

Four new carbazole alkaloids, clausenawallines C-F (1-4), along with 18 known compounds (5-22) were isolated from the roots of Clausena wallichii. Compounds 3, 9, and 22 exhibited significant antibacterial activity against methicillin-resistant Staphylococcus aureus SK1 (MRSA SK1) and Staph. aureus TISTR 1466 with MIC values in the range 4-16 μg/mL, whereas compound 4 showed the highest cytotoxicity against oral cavity cancer (KB) and small-cell lung cancer (NCI-H187) with IC(50) values of 10.2 and 4.5 μM, respectively., (© 2012 American Chemical Society and American Society of Pharmacognosy)

THE TITLE COMPOUND KNOWN AS GLYCOZOLIDAL (SYSTEMATIC NAME: 2,7-dimeth-oxy-9H-carbazole-3-carbaldehyde), C(15)H(13)NO(3), is a naturally occurring carbazole, which was isolated from the roots of Clausena lansium. The carbazole ring system is essentially planar, with an r.m.s. deviation of 0.0093 (1) Å. In the crystal, inter-molecular N-H⋯O hydrogen bonds connect the mol-ecules into a chain along the c axis. C-H⋯O, C-H⋯π and π-π inter-actions, with centroid-centroid distances of 3.5924 (6), 3.6576 (6) and 3.8613 (6) Å, are also observed.

The title compound {systematic name: 7-meth-oxy-6-[(1R,2R,5R)-5-methyl-4-oxo-3,6-dioxabicyclo-[3.1.0]hexan-2-yl]-2H-chromen-2-one}, C(15)H(12)O(6), is a coumarin, which was isolated from the roots of Micromelum glanduliferum. There are two mol-ecules in the asymmetric unit with slight differences in bond angles. In both mol-ecules, the furan ring adopts a flattened envelope conformation. In the crystal, mol-ecules are linked by weak C-H⋯O inter-actions into chains along the a axis. Aromatic π-π stacking inter-actions with centroid-centroid distances in the range 3.6995 (11)-3.8069 (11) Å and C⋯O short contacts [3.030 (2)-3.171 (3) Å] also occur.

A new furanocoumarin named lucidafuranocoumarin A (7) together with 13 known coumarins (1-6, 8-14) and four known alkaloids (15-18) was isolated from the roots of Feroniella lucida. Their structures were elucidated on the basis of spectroscopic analysis. Some of the isolates were evaluated for their biological activities, and compound 18 showed strong cytotoxicity against KB (IC(50) = 0.637 μg/ml) and NCI-H187 (IC(50) = 0.094 μg/ml) human cancer cell lines, antimalarial activity against Plasmodium falciparum (IC(50) = 0.336 μg/ml), and antituberculosis activity against Mycobacterium tuberculosis (MIC = 6.25 μg/ml).

In the title compound, C(19)H(20)O(5), the pyran ring is in an envelope conformation, whereas the benzene and dihydro-pyran ring system is planar with an r.m.s. deviation of 0.0190 (1) Å. The hy-droxy group is coplanar with the attached benzene ring [r.m.s. deviation = 0.0106 (1) Å]. An intra-molecular O-H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked into chains along the b axis by weak C-H⋯O inter-actions. These chains are stacked along the a axis. C-H⋯π and weak π-π inter-actions [centroid-centroid distance = 3.7698 (7) Å] are also observed.