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Two new merosesquiterpenes, hippomeroterpenes A and B (1 and 2), and four known compounds langconol B (3), 20-demethoxy-20-methylaminodactyloquinone D (4), smenospongidine (5), and smenospongic acid (6) were isolated from the sponge Hippospongia fistulosa. Their structures were determined by extensive analyses of HR ESI MS and NMR spectral data. At concentration of 100 μM, compounds 1-6 exhibited weak cytotoxic effects on Hep-G2, MCF-7, SK-LU-1, and SK-Mel-2 human cancer cells with percentages of dead cells ranging from 8.3 ± 0.3%–36.3 ± 1.5 %.

Four new dihydrostilbene glycosides, assastilbosides A–D (1-4), along with seven known compounds, 5,4′-dihydroxydihydrostilbene 3-O-β- d -glucopyranoside (5), 3,5-dihydroxydihydrostilbene 4′-O-β- d -glucopyranoside (6), 3,5-dihydroxydihydrostilbene 4′-O-[6′′-O-(4′′′-methoxy)galloyl]-β- d -glucopyranoside (7), 3,5-dimethoxydihydrostilbene 4′-O-α- l -rhamnopyranosyl-(1→6)-β- d -glucopyranoside (8), (­)-epicatechin (9), (­)-epicatechin 3-O-gallate (10), and (-)-epigallocatechin 3-O-gallate (11) were isolated from methanol extract of the leaves of Camellia sinensis var. assamica (J.W.Mast.) Kitam. Their structures were elucidated by HR-ESI-MS, 1D- and 2D-NMR spectra and compared with NMR data in the literature. In addition, all isolated compounds were screened by α-glucosidase assay. Compounds 10 and 11 showed significant inhibitory α-glucosidase with IC50 values of 18.3 ± 1.1 and 21.9 ± 0.8 μM, respectively.

Four new aaptamine alkaloids, named as 9-methoxy-N-demethylaaptanone (1), 3,5-dicarbomethoxy-1,​6-​naphthyridine (2), aaptosvanphongs A and B (3 and 4), and three known aaptamine alkaloids as 2-methoxy-3-oxoaaptamine (5), 8,9,9-trimethoxy-9H-benzo[de][1,6]-naphthyridine (6), and demethyl(oxy)aaptamine (7) were isolated from the sponge Aaptos by various chromatographic methods. Their structures were established by extensive spectroscopic analyses (HR-ESI-MS, 1 D and 2 D NMR) and by comparison of the spectral data with those reported in the literature. Compounds 1-7 significantly showed cytotoxic effects against SK-LU-1, MCF-7, HepG2, and SK-Mel-2 cell lines with IC50 values in range from 7.7 ± 0.8 to 51.4 ± 1.8 µM. Among them, compound 7 exhibited the most cytotoxic activity with corresponding IC50 values of 9.2 ± 1.0, 7.8 ± 0.6, 8.4 ± 0.8, and 7.7 ± 0.8 µM.

Two new sucrose derivatives, named as cannadica A (1) and cannadica B (2), and eight known compounds, 6′-O-acetyl-3-O-(E)-p-coumaroylsucrose (3), heterophylloside C (4), 6′-O-vanilloylarbutin (5), isotachioside (6), 2,6-dimethoxy-p-hydroquinone 1-O-β-D-glucopyranoside (7), 3,5-dimethoxy-p-hydroquinone 1-O-β-D-glucopyranoside (8), benzyl glucoside (9), and 3,4-dihydroxybenzaldehyde (10) were isolated from the roots of Canna indica L. by various chromatographic methods. Their structures were established by extensive spectroscopic analysis (UV, IR, HR-ESI-MS and NMR) and by comparison of the spectral data with those reported in the literature. Compounds 1-10 were evaluated their antioxidant activity by peroxyl radical absorbance capacity assay. Compounds 4 and 5 exhibited the most peroxyl radical absorbance capacity. At concentration of 1 µM, their ORACROO* values were 4.86 ± 0.39 and 3.11 ± 0.26, respectively, fold-up to that of trolox as an internal standard.

Three new pregnane glycosides, drevoluosides O-Q (1-3) along with five known volubiloside C (4), dreageoside A11 (5), 17β-marsdenin (6), stavaroside H (7), and hoyacarnoside G (8) were isolated from the methanol extract of the Dregea volubilis leaves. Their structures were elucidated by chemical and spectroscopic methods. Compounds 6-8 showed significant anti α-glucosidase activity with the inhibitory percentages ranging from 32.6 to 47.1% at the concentration of 200 μM. Compound 3 showed significant inhibitory α-amylase activity with IC50 value of 51.3 ± 2.1 μM.

Three new muurolane type sesquiterpene glycosides, named balanoindicosides A − C (1 − 3), were isolated from the whole plant of Balanophora fungosa subsp. indica using various chromatographic methods. Their structures were determined by extensive analysis of HR-ESI-MS and NMR spectroscopy. The stereochemistry of muurolane sesquiterpene backbone was demonstrated by NOESY analysis. Configuration of C-12 in compounds 2 and 3 could be distinguished by chemical shift value of C-14. Compounds 1-3 exhibited weak cytotoxic activity towards HepG-2, HL-60, LU-1, and MCF-7 cell lines.

Gymnema sylvestre, a medicinal plant, has been used in Indian ayurvedic traditional medicine for the treatment of diabetes. Phytochemical investigation of Gymnema sylvestre led to the isolation of five new pregnane glycosides, gymsylosides A&ndash, E (1&ndash, 5) and four known oleanane saponins, 3&beta, O-&beta, D-glucopyranosyl (1&rarr, 6)-&beta, D-glucopyranosyl oleanolic acid 28-O-&beta, D-glucopyranosyl ester (6), gymnemoside-W1 (7), 3&beta, D-xylopyranosyl-(1&rarr, D- glucopyranosyl-(1&rarr, D-glucopyranosyl ester (8), and alternoside XIX (9). Their structures were identified based on spectroscopic evidence and comparison with those reported in the literature. All compounds were evaluated for their &alpha, glucosidase and &alpha, amylase inhibitory activities. Compounds 2&ndash, 4 showed significant &alpha, amylase inhibitory activity, with IC50 values ranging from 113.0 to 176.2 &micro, M.

Four new pregnane glycosides, gymlatifosides A - D (1 − 4) and one known pregnane glycoside, verticilloside J (5) were isolated from the leaves of Gymnema latifolium Wall. ex Wight. Their chemical structures were elucidated on the basis of extensive spectroscopic methods, including 1D, 2D NMR, HR-ESI-MS, and in comparison with the reported data. All these compounds were tested for α-glucosidase and α-amylase inhibitory activities. Compound 5 exhibited the most anti α-glucosidase activity with inhibitory percentage of 37.8 ± 1.5% at the concentration of 200 μM. Compounds 1–4 showed moderate anti α-glucosidase activity with inhibitory percentage ranging from 7.0 to 30.1%. In addition, all compounds 1–5 showed moderate/weak anti α-amylase activity in the investigated test.

A total of 4 thiazinedione derivatives including 1 new thiazinedione glycoside (1) and 3 known compounds (2-4) were isolated from the fruits of Xanthium strumarium L. Their chemical structures were determined as 7-hydroxymethyl-8,8-dimethyl-4,8-dihydrobenzo[1,4]-thiazine-3,5-dione-11- O-[ β-D-glucopyranosyl-(1→6)- O-β-D-glucopyranoside] (1), 7-hydroxymethyl-8,8-dimethyl-4,8-dihydrobenzo[1,4]-thiazine-3,5-dione-11- O-[ β-D-apiofuranosyl-(1→6)- O- β-D-glucopyranoside] (2), xanthiside (3), and xanthiazone (4) by extensive nuclear magnetic resonance spectroscopic and high-resolution electron spray ionization mass spectrum analysis and by comparison of the spectral data with those reported in the literature. Compounds 3 and 4 exhibited cytotoxic activity against lung carcinoma (SK-LU-1), human breast carcinoma (MCF-7), hepatocellular carcinoma (HepG2), and skin melanoma (SK-Mel-2) cell lines with half-maximal inhibitory concentration (IC50) values ranging from 27.0 ± 1.1 to 43.2 ± 1.8 µM.

Seven compounds (1-7) were isolated from the marine sponge Aaptos aaptos living in the Vietnamese sea. Their structures were determined as 2 hours, 5 H,7 H,9 H-9 S-hydroxy-imidazo[1,5- α]pyridine-1,3-dione (1), 3-([9-methylhexadecyl]oxy)propane-1,2-diol 2, 2,3-dihydro-2,3-dioxoaaptamine (3), indol-3-aldehyde (4), methyl indole-3-carboxylate (5) 4-hydroxy-5-(indole-3-yl)−5-oxo-pentan-2-one (6), and thymidine (7) by extensive analysis of HR-ESI-MS, 1D, and 2D NMR spectral data, as well as by comparison of the spectral data with those reported in the literature. In addition, the absolute configuration of 1 was determined from the experimental ECD spectrum and comparison of this with the theoretical ECD calculations using the TDDFT method. Compounds 1 and 2 were isolated from nature for the first time. Compound 3 induced cytotoxic activity against SK-LU-1, MCF-7, HepG2, and SK-Mel-2 cell lines with IC50 values of 41.27 ± 2.63, 40.70 ± 2.65, 34.31 ± 3.43, and 36.63 ± 1.40 µM, respectively.

Two new acylated sucroses, (6- O-axetoxyl)- β-d-fructofuranosyl-(2→1)-(6- O-feruloyl- α- d-glucopyranoside (1) and (6- O-axetoxyl)- β-d-fructofuranosyl-(2→1)-(6- O-( E)- p-coumaroyl- α- d-glucopyranoside (2), and four known compounds, 2-(3′,4′-dihydroxyphenyl)-1-propanol-4′- O-[4′′′-hydroxy-3′′′,5′′′-dimethoxybenzoyl-(→6′′)- β-d-fructofuranoside (3), tryptophol glucoside (4), corchonoside C (5), and 2-hydroxy-5-(2-hydroxyethyl)phenyl β-d-fructofuranoside (6), were isolated from the roots of Canna indica L. (Cannaceae). Their structures were determined by extensive analysis of HR-ESI-MS, 1D, and 2D NMR spectral data, as well as by comparison of these with those reported in the literature. Antioxidant activity of compounds 1-6 were evaluated by peroxyl radical absorbance capacity assay. Compounds 1 and 3 neutralized high amounts of peroxyl radical. At a concentration of 1 µM, their ORACROO* values were 3.07 ± 0.15 and 4.27 ± 0.30, respectively, many times greater than that of trolox, which was used as an internal standard. At 10 µM, the peroxyl radical absorbance capacity of compounds 1 and 3 exhibited equivalents to 15.60 ± 0.22 and 24.91 ± 0.43 times the net protection by 1 µM of trolox.

Two new pregnane glycosides, gyminosides A and B (1 and 2) and three known, tinctoroside B (3), tinctoroside C (4), and gymnepregoside F (5) were isolated from the leaves of Gymnema inodorum (Lour.) Decne. Their structures were elucidated by physical and chemical methods and comparing with those reported in the literature. All these compounds were evaluated for α-glucosidase assay. Compound 5 exhibited the most anti α-glucosidase activity with inhibitory percentage of 63.7 ± 3.9% at the concentration of 200 μM. Compounds 1–4 showed moderate anti α-glucosidase activity with inhibitory percentage ranging from 40.0 to 52.1%.

Using various chromatographic methods, two new alkaloids, antidesoic acids A (1) and B (2) along with fourteen known compounds (3-16) were isolated from the leaves of Antidesma ghaesembilla Gaertn. Their chemical structures were elucidated by physical and chemical methods. All the isolated compounds were evaluated for their inhibitory activity on LPS-stimulated nitric oxide (NO) production in BV2 cells and RAW 264.7 macrophages. Bisflavone 8 significantly inhibited LPS-stimulated NO production in BV2 cells and RAW 264.7 macrophages with IC50 values of 5.4 and 8.0 μM, respectively. Compounds 1–3, 7, 10, 12, 14, and 16 showed moderate inhibitory activities with IC50 values ranging from 11.7 to 77.4 μM.

Phytochemical investigation of the methanol extract of Vitex limonifolia leaves led to the isolation of three new labdane-type diterpenoids, vitexlimolides A–C (1–3) and eight known compounds, 5,4′-dihydroxy-3,7-dimethoxyflavone (4), vitecetin (5), 5,4′-dihydroxy-7,3′-dimethoxyflavone (6), verrucosin (7), 2α, 3α-dihydroxy-urs-12-en-28-oic acid (8), euscaphlic acid (9), 18,19-seco, 2α, 3α-dihydroxy-19-oxo-urs-11,13(18)-dien-28-oic acid (10), and maslinic acid (11). Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for antiviral activities against CVB3, HRV1B, and EV71 viruses. As a result, compounds 4 and 6 showed potent antiviral activity against CVB3 infection with IC50 values of 0.12 ± 0.06 and 1.86 ± 0.18 (µM), respectively.

Inhibitory effects of NO production in RAW 264.7 macrophages guided the isolation of nine prenylated isoflavones, including a new cudraisoflavone L (1) and eight known metabolites furowanin B (2), erysubin A (3), wighteone (4), lupalbigenin (5), laburnetin (6), isolupalbigenin (7), 6,8-diprenylorobol (8), millewanin H (9) from the leaves of Cudrania tricuspidata. At the concentration of 10 μM, compounds 1, 2, and 4 significantly inhibited NO production with the inhibitory values of 72.5 ± 2.4, 66.9 ± 1.8, and 55.4 ± 2.7%, respectively. In addition, all of isolated compounds 1–9 showed promising cytotoxic effects toward HL-60 cells (IC50 4.3 ± 0.7 to 18.0 ± 1.7 μM).

Two new steroidal alkaloid saponins, solanigrosides Q and R (1 and 2), together with four known compounds khasianine (3), solamargine (4), solasonine (5), and soladulcoside A (6) were isolated from the whole plants of Solanum nigrum. The structures of new compounds (1 and 2) were determined by interpretation of HR-ESI-MS, 1D and 2D NMR spectra, and chemical transformation. Compound 4 exhibited potent cytotoxic activity against MDA-MB-231, A549, Hep3B, PC3 human cancer cell lines with IC50 values of 1.86 ± 0.45, 2.24 ± 0.15, 0.78 ± 0.11, 5.13 ± 1.34 μM, respectively.

Using various chromatographic methods, one new lanostane triterpene, 3 α-hydroxylanosta-8,24 E-dien-26-oic acid (1), one new lignan, matairesinol 4'- O-β-D-glucopyranoside (2) along with five known compounds, ecdysone (3), 20-hydroxyecdysone (4), 20-hydroxyecdysone 2,3-monoacetonide (5), turkesterone (6), and polypodine B (7) were isolated from the leaves of Vitex trifolia L. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis, HR-ESI-MS, CD, and by comparing with the NMR data reported in the literature.

One new tirucallane- type triterpene glycoside, antidesoside (1), along with two biflavones, podocarpusflavone A (2) and amentoflavone (3) and two megastigmane glycosides, byzantionoside B (4), and (6 S,9 R)-roseoside (5) were isolated from the methanol extract of Antidesma bunius leaves. Their structures were determined by spectroscopic methods and in comparison with the published data. Compounds 1 - 3 were found to show strong inhibitory effect of NO production in BV2 cells and RAW264.7 macrophages LPS-stimulated, with IC50 values ranging from 8.5 to 26.9 μM.