Two new flavonol glycosides from the leaves of Cleome chelidonii L.f.

From the leaves of Cleome chelidonii L.f., two new flavonol glycosides, named cleomesides A (1) and B (2), and four known compounds, quercetin 3-O-β-glucopyranosyl(1 → 2)-α-rhamnoside-7-O-α-rhamnoside (3), ethyl α-galactopyranoside (4), adenine (5) and glycerol monostearate (6), were isolated. The structures of all isolated compounds (1–6) were determined by NMR spectroscopy and mass spectrometry. The data of known compounds (3–6) were further compared with the reported data for these compounds.     

Uncinataflavone,a new flavonoid with a methyl benzoate substituent from Selaginella uncinata

Uncinataflavone (1), a new flavonoid, together with four known compounds (2–5), was isolated from Selaginella uncinata (Desv.) Spring. Compounds 2 and 3 were isolated from the genus selaginella for the first time. The structure of the new compound was determined as methyl 3-(5,7-dihydroxy-2-(4-hydroxyphenyl)-4-oxo-4H-chromen-6-yl)-4-methoxybenzoate by means of spectroscopic evidence, including UV, IR, 1D and 2D NMR analyses as well as HR-ESI-MS. These compounds (1–5) were evaluated for the antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl assay system.     

Trichodermatides E and F from fungus Trichoderma applanatum

Two new polyketide derivatives, trichodermatides E (1) and F (2), are unprecedented examples of a polyketide with 6/6/6/6 tetracyclic skeleton, together with five known analogs koninginin B (3), koninginin D (4), 7-O-methylkoninginin D (5), koninginins E and F (6–7), were isolated from the plant endophytic fungus Trichoderma applanatum. The structures of these two compounds were determined by NMR data and HR-ESI-MS analysis. The putative biosynthesis of compounds 1–7 was presented.     

Three new compounds from Cinnamomum cassia

Three new compounds, including two new diterpenoids, named epianhydrocinnzeylanol (1) and cinnacasiol H (2), and one hydroxylasiodiplodin, (3R,4S,6R)-4,6-dihydroxy-de-O-methyllasiodiplodin (3), together with five known diterpenoids (4–8) and two known phenolic glycosides (9–10) were isolated from the barks of Cinnamomum cassia. Their structures were elucidated by extensive spectroscopic analysis and comparison of the chemical shift values with those of related known compounds. The anti-inflammatory activities of the isolates were evaluated on nitric oxide production in lipopolysaccharide-induced BV-2 microglial cells and the compounds showed weak inhibition activities.     

Suaeglaucin A,a new coumaronochromone from Suaeda glauca

Abstract

A new isoflavane, suaeglaucin A (1), which was isolated from the herb of Suaeda glauca (Bunge) Bunge, was elucidated as 5,6,8-trimethoxy-7- hydroxycoumaronochromone based on its MS and 1D and 2D NMR spectroscopic data. The structure of compound 1 was confirmed by X-ray crystallographic analysis. Five known compounds (2–6) were also isolated. All compounds were isolated for the first time from Chenopodiaceae. We found that compounds 2 and 4 possessed moderate antioxidant activity.     

A new ursane-type triterpenoid from Schefflera heptaphylla (L.) Frodin

A new ursane-type triterpenoid (1), together with 15 known compounds (2–16), was isolated from the barks of Schefflera heptaphylla (L.) Frodin. The structure of the new compound was determined on the basis of extensive spectroscopic data including IR, HR-ESI-MS, 1D and 2D NMR, and further confirmed by single-crystal X-ray diffraction. Compounds 2–6 were isolated from Schefflera genus for the first time.     

Four new monoterpenoids from the whole plants of Valeriana stenoptera

Four new monoterpenoids, including two new acyclic monoterpenoids (2R, 6R)-2, 6-dimethyl-8-isovaleroxyoctan-1-ol (1) and (2S, 6S)-2, 6-dimethyl-8-isovaleroxyoctan-1-ol (2), as well as two new iridoids stenopterins F-G (3 and 4), together with fifteen known compounds (5–19), were isolated from whole dried material of Valeriana stenoptera. Stenopterin F was the first reported iridoids with n-butoxyl in the Valerianaceae family. The structures of new compounds were established on the basis of extensive spectroscopic analysis.

     

Sesquiterpenoids from the roots of Croton crassifolius

Phytochemical investigation of Croton crassifolius roots afforded five sesquiterpenes (1–5), including two new sesquiterpenes 6S-hydroxy-cyperenoic acid (1) and crassifterpenoid A (5), together with three known compounds (2–4). The structures of the new compounds were determined by comprehensive spectroscopic methods, and their absolute configurations were determined by quantum chemical ECD calculation. Crassifterpenoid A (5) is the first germacrane-type sesquiterpene isolated from C. crassifolius, which enriched the diversity of chemical constituents in Croton crassifolius. In addition, the cytotoxicities of all compounds against human liver cancer lines HepG2 and Hep3B were determined, but none showed significant activity.     

Isolation and characterization of a new bioactive isoflavone from Derris eriocarpa

Derris eriocarpa How is an important medicinal plant, which is used as Zhuang ethnomedicine and Dai ethnomedicine to treat various diseases. One new compound, 3′,4′-di-O-methylene-5-hydroxy-7-methoxy-6-isopentenyl isoflavone (1) and a known synthetic but new naturally occurring compound trans-3,4,5-trimethoxy-4′-isopentenyloxyl-stilbene (2), together with five known compounds, 5,7-dimethoxy-6-(3-methyl-2-butenyl)-4′-hydroxyl isoflavones (3), robustone (4), trans-3,4,5,4′-tetramethoxy-stilbene (5), robustic acid (6), and robustin (7) were isolated from the stem of D. eriocarpa. Spectroscopic analysis revealed the chemical structures of compounds 1–7.. Compounds 1 and 3 exhibited significant scavenging activities against 1,1-diphenyl-2-picrylhydrazyl radical and superoxide anions. Compounds 1–3 exhibited potent antiproliferative activity on Hela cells.     

Five new compounds from Dendrobium crystallinum

Five new compounds, dencryol A (1), dencryol B (2), crystalltone (3), crystallinin (4), and 3-hydroxy-2-methoxy-5,6-dimethylbenzoic acid (5), together with six known compounds, dendronobilin B (6), syringic acid (7), apigenin (8), isoviolanthin (9), 6?-glucosyl-vitexin (10), and palmarumycin JC2 (11), have been isolated from the stems of Dendrobium crystallinum, of which compounds 9–11 were isolated from the genus Dendrobium for the first time, and all the other compounds were first obtained from this plant. Their structures were established on the basis of spectroscopic analysis and literature data.     

Two new lignan glycosides from the fruits of Pyrus ussuriensis

Two new lignan glycosides, ussuriensislignan A (1) and ussuriensislignan B (2), together with seventeen known compounds (3–19), were isolated from the fruits of Pyrus ussuriensis. Their structures were determined by various spectroscopic methods. This is the first report of the isolation of lignans (compounds 1–3) from the genus Pyrus, and compounds 3–6, 12–16 were reported from Pyrus for the first time.     

Exopisiod B and farylhydrazone C,two new alkaloids from the Antarctic-derived fungus Penicillium sp. HDN14-431

Two new compounds, exopisiod B (1) and farylhydrazone C (2), together with two known compounds (3–4), were isolated from the Antarctic-derived fungus Penicillium sp. HDN14-431. Their structures including absolute configurations were elucidated by spectroscopic methods and TDDFT ECD calculations. The cytotoxicity and antimicrobial activities of all compounds were tested.     

Limonoid constituents of Euodia rutaecarpa var. bodinieri and their inhibition on NO production in lipopolysaccharide-activated RAW264.7 macrophages

A new limonoid compound, named evorubodinin (1), was isolated from the dried and nearly ripe fruits of Euodia rutaecarpa (Juss.) Benth. var. bodinieri (Dode) Huang (family Rutaceae), together with two known limonoid compounds, limonin (2) and evolimorutanin (3). The chemical structure of 1 was elucidated by spectroscopic method and single-crystal X-ray diffraction. The inhibitory effects of the isolated compounds 1–3 and the structurally related compounds evodol (4), shihulimonin A1 (5), evodirutaenin (6), 12α-hydroxyrutaevin (7), and rutaevin (8) on nitric oxide (NO) production in lipopolysaccharide-activated RAW264.7 macrophages were also assayed. All compounds 1–8 showed the inhibitory activity, in which both 7 and 8 with the uncommon 5β-H configuration more efficiently inhibited NO production. The results provided valuable information for further investigation of compounds 1–8 as anti-inflammatory agents or lead compounds.     

Two new metabolites from Daldinia eschscholtzii,an endophytic fungus derived from Pogostemon cablin

The chemical investigation of the mycelia of endophytic fungus Daldinia eschscholtzii A630, which was isolated from the medicinal plant Pogostemon cablin, resulted in the isolation of two new compounds, named eschscholin A (1), 3-ene-2-methyl-2H-1-benzopyran-5-ol (2), and one new natural product 3,5-dihydroxy-2-methyl-4H-chromen-4-one (3), along with seven known compounds. Their structures were fully characterized by means of detailed spectroscopic analysis, and in comparison with published data for known compounds. All of the isolated compounds (1–10) were evaluated for their antibacterial activities.     

Polyanthumin,a novel cyclobutane chalcone trimmer from Memecylon polyanthum

A novel unusual trimmer chalcone, polyanthumin (1), together with five known compounds myricetin 3-O-(3″-O-galloyl)-α-l-rhamnopyranoside (2), sulfuretin (3), fustin (4), gallic acid (5), and ethyl gallate (6), was isolated from the dry stems of Memecylon polyanthum H.L. Li. Among them, compound 1 is a new chalcone trimmer with a novel cyclobutane skeleton in nature. Compounds 3 and 4 are flavonoids carrying a single 7-OH in A ring, which provided the first example of these class flavonoids from the family Melastomataceae. In addition, the antitumor activities for 2–4 were reported for the first time in this study. The antitumor effects of the isolated compounds 1–6in vitro were assayed by the SRB method using human cancer K562 cells, with the inhibition rates ranging from 39.4% to 54.5% at 100 μg/ml. The IC₅₀ values of compounds 1 and 3 for the inhibition of K562 cell proliferation were determined to be 45.4 and 30.5 μg/ml, respectively. To the best of our knowledge, compound 1 was the second sample as chalcone trimer. In addition, the antitumor activities for 2–4 were reported for the first time in this study.     

A new prenylated flavone from Pleione bulbocodioides

A new prenylated flavone, 3,5,7,3′-tetrahydroxy-8,4′-dimethoxy-6-(3-methylbut-2- enyl)flavone (1), together with three known flavone derivatives (2–4), two known dihydrophenanthrenes (5–6), two known lignin derivatives (7–8), and three known phenolic glycoside compounds (9–11) were isolated from the n-BuOH extract of Pleione bulbocodioides. High-resolution electrospray ionization mass spectroscopy (HRESIMS), FTIR spectroscopy, and NMR techniques were used to elucidate the structures of these compounds. Biological investigations showed that compound 5, 4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene, exhibited potent anti-inflammatory activity on LPS-stimulated NO production in BV-2 microglial cells, with IC₅₀ value of 5.44 μM.     

Prenylated C6–C3 compounds from the fruits of Illicium simonsii

Two new prenylated C₆–C₃ compounds, 4-epi-illicinone E-12-shikimate (1) and 3-hydroxyillifunone B (2), together with five known prenylated C₆–C₃ compounds (3–7), were isolated from the fruits of Illicium simonsii. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D and 2D NMR, CD spectra, and ESI-MS analysis.     

Novel polyhydroxylated steroids from the East China Sea gorgonian Echinogorgia sassapo reticulata with suppressive activity of leukotriene C4 generation and degranulation in bone marrow-derived mast cells

The gorgonian Echinogorgia sassapo reticulata contains two new bioactive polyhydroxylated steroids, sassapols A (1), B (2), and five related known compounds (3–7). Compound 6 has been encountered for the first time in natural sources. The structures of these new compounds were defined by spectroscopic analysis. All the compounds (1–7) isolated from E. sassapo reticulata were tested for anti-inflammatory activity. Compounds 1, 3, 5, and 7 inhibited both the generation of leukotriene C₄ and the degranulation reaction in mouse bone marrow-derived mast cells.     

Diterpenoids from the freshwater green algae Rhizoclonium hieroglyphicum with antibacterial activity

Three new isopimarane diterpenes 7β-hydroxy-19α-methylmalonyloxy-isopimara-8(14),15-diene (1), 7β-hydroxy-14-oxo-isopimara-8(9),15-dien-19oic acid (2), and 7β-hydroxy-14-oxo-19α-methylmalonyloxy-isopimara-9(11),15-diene (3) in addition to the known compounds isopimaric acid (4), 7oxo-13-epi-pimara-14,15-dien-18oic acid (5), 7oxo-13-epi-pimara-8,15-dien-18oic acid (6), and 6β-hydroxyisopimaric acid (7) were isolated from the hexane extract of Rhizoclonium hieroglyphicum. The structures of compounds 1–7 were established by 1D and 2D NMR techniques. The isolated diterpenoids were screened for antimicrobial activity against gram-positive and gram-negative bacteria and yeast strains.     

Two new dammarane monodesmosides from Centella asiatica

Two new dammarane monodesmosides centellosides A (1) and B (2), and two new natural products ginsenosides Mc (10) and Y (11), together with 11 known compounds (3–9 and 12–15) reported for the first time from this genus, were isolated from the whole plants of Centella asiatica. All structures were elucidated by spectroscopic techniques and chemical methods, and compared with literature values. All the isolated compounds were evaluated in vitro for cytotoxicity.