A New Coumarin and Carbazole Alkaloid from Clausena vestita D. D. Tao

Phytochemical investigation of the EtOH extract of Clausena vestita D. D. Tao led to the isolation of one new coumarin, clauslactone U ( 1 ), and one new carbazole alkaloid, clauszoline N ( 2 ), together with 28 known compounds. The structures of these compounds were established by using MS and 1D‐ and 2D‐NMR techniques, and by comparison with known analogues.     

Spicachlorantins G-J, new lindenane sesquiterpenoid dimers from the roots of Chloranthus spicatus

Four new lindenane sesquiterpenoid dimers, spicachlorantins G-J (1-4), were isolated from the roots of Chloranthus spicatus together with seven known compounds, including chloramultilide A, shizukaol B, shizukaol D, shizukaol F, shizukaol P, chlorahololide D, and cycloshizukaol A. The planar structures of the new compounds were established by 1D-, 2D-NMR, and MS analyses. The absolute configurations of these compounds were determined by analyzing rotating Overhauser enhancement and exchange spectroscopy (ROESY) and circular dichroism (CD) spectra.     

Complete 1H and 13C data assignments of two new guaianolides isolated from Ainsliaea fragrans

Two new guaianolides, 8alpha-hydroxy-11alpha,13-dihydroglucozaluzanin C and 11alpha,13-dihydroglucozaluzanin C, were isolated from Ainsliaea fragrans, along with two known guaianolides, 8alpha-hydroxy-11alpha,13-dihydrozaluzanin C and glucozaluzanin C. The structures of the new compounds were unambiguously established by HR-ESI-MS, one-dimensional (1D) (DEPT), two-dimensional (2D) ((1)H-(1)H COSY, HSQC, HMBC, ROESY) NMR experiments and by comparison with structurally related compounds. The known compounds were identified by comparison of spectral data with published references. Some NMR data of the known compounds were reported for the first time.     

Cytotoxic cassane diterpenoids from the seeds of Caesalpinia sappan

Phytochemical investigation on the seeds of Caesalpinia sappan led to the isolation of five new cassanetype diterpenoids, named 11-oxo-phanginin A(1), caesalsappanins O–Q(2–4) and phanginin U(5),together with five known compounds. The structures of the new compounds were elucidated by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. All the new compounds showed moderate cytotoxic effects on human breast cancer MCF-7 and human colon cancer HCT116 cell lines.     

Three New Phenol Compounds from Iris dichotoma Pall.

Three new phenolic compounds, irisdichototins D, E, and F ( 1 – 3 , resp.) were isolated from the stems of Iris dichotoma. The structures of the new compounds were elucidated by spectroscopic analyses, including 2D‐NMR techniques.     

Two new lactones and one new aryl-8-oxa-bicyclo[3,2,1]oct-3-en-2-one from Descurainia sophia

Two new lactones (1, 2), descurainolide A and B, and one new aryl-8-oxa-bicyclo[3,2,1]-oct-3-en-2-one (3), descurainin, together with five known compounds (4-8), were isolated from the seeds of Descurainia sophia (L.) WEBB ex PRANTL. The structures of the new compounds were elucidated by extensive studies of their 1D, 2D NMR and HR-MS. Compounds 4 and 5 showed cytotoxicity.     

Lipid constituents of Trifolium resupinatum var. microcephalum

The two new compounds (3-methyl-1-nonene-3-ol and 2',3'-dihydroxy propyl pentadecanoate) and four known compounds were isolated from Trifolium resupinatum L. var. microcephalum Zoh. (Leguminosae). All the compounds were reported for the first time from this plant. The stuructures of the isolates were determined by 1D, 2D NMR techniques and MS spectroscopy.     

Sesquiterpene compounds from Inula viscosa

Two new compounds, 2,5-dihydroxyisocostic acid and 2,3-dihydroxycostic acid together with three known sesquiterpene compounds, Isocostic acid, Carabrone and Tomentosin, have been isolated from the acetone extract of Inula viscosa (L.) Aiton. The structures of all new compounds were determined by spectroscopic methods, in particular 1D and 2D (1)H- and (13)C-NMR. The (13)C-NMR spectra of Isocostic acid and of Tomentosin are reported here for the first time.     

Iridoids from Neopicrorhiza scrophulariiflora and their hepatoprotective activities in vitro

Four new non-glycosidic iridoids, piscrocins D (1), E (2), F (6), and G (7), as well as two new iridoid glycosides, piscrosides A (8) and B (9), were isolated from the roots of Neopicrorhiza scrophulariiflora (Scrophulariaceae), together with seven known iridoids. The structures of the isolated compounds were established by means of 1D and 2D NMR spectroscopy and chemical methods. The hepatoprotective activities of these compounds were evaluated by measuring their effects on CCl(4)-induced hepatocytes damage in vitro, and the structure-activity relationships were also discussed.     

New 3,4-seco-ent-kaurene dimers from Croton micans

From the stems of Croton micans Sw., five new 3,4-seco-ent-kaurene dimers: micansinoic acid (1), isomicansinoic acid (2), and the dimethyl (3), monomethyl (4) and monoethyl ester (5) of micansinoic acid were isolated. The structures of the new compounds were elucidated by spectroscopic data interpretation, mainly 1D and 2D NMR experiments and MS. These compounds are the first 3,4-seco-ent-kaurene dimers from a Croton species.     

New Isoprenylated Aurones from the Flowers of Rosa damascena

A phytochemical investigation of the flowers of Rosa damascena resulted in the isolation of three new isoprenylated aurones, damaurones C–E ( 1 – 3 , resp.), together with six known compounds, 4 – 9 . The structures of the new compounds were elucidated by spectroscopic methods, including extensive 1D‐ and 2D‐NMR experiments.     

Diterpenes from Sideritis trojana

Six known ent-kaurene, a new ent-kaurane and a new pimarane diterpenes were isolated from Sideritis trojana. The structures of new compounds were determined as ent-7alpha-15beta,16beta-epoxykaurane (1), and ent-2alpha-hydroxy-8(14),15-pimaradiene (2) along with the known compounds siderol (3), sideridiol (4), 7-epicandicandiol (5), isocandol B (6), candol A acetate (7) ent-7alpha-acetoxykaur-15-ene (8) by IR, 1D and 2D NMR techniques and HRMS.     

A new phenolic glycoside from the stems of Hydnocarpus hainanensis

A new phenolic glycoside (1) was isolated from the stems of Hydnocarpus hainanensis, along with 11 known compounds. The structures of all compounds were deduced using 1D, 2D NMR spectroscopic methods. The anti-oxidation activities of several compounds were also evaluated.     

1H and 13C NMR spectral assignments of four dammarane triterpenoids from carnauba wax

The phytochemical investigation of carnauba wax led to the isolation of three new dammarane triterpenoids 1, 2 and 4, together with the known triterpene 3. The structures of the new compounds were determined by 1D and 2D NMR spectroscopy and by comparison with published data for closely related compounds.     

Iridoid Glycosides from Hedyotis corymbosa

Three new iridoid glycosides, hedycorysides A–C ( 1 – 3 , resp.), were isolated from the whole plant of Hedyotis corymbosa (Linn .) Lam ., along with four known compounds. Their structures were elucidated by extensive 1D‐ and 2D‐NMR analysis, as well as by HR‐ESI‐MS experiments. The three new compounds are the first benzoylated geniposide derivatives from Hedyotis.     

Chemical constituents of the Gorgonian Dichotella fragilis (Ridleg) from the South China Sea

Two new steroidal glycosides, fragilioside A (1) and fragilioside B (2), along with five known compounds (3-7) were isolated from the gorgonian Dichotella fragilis (Ridleg) collected from the South China Sea. The structures of the new compounds (1 and 2) were elucidated by comprehensive analysis of spectral data, especially 2D NMR. The brine shrimp lethality and antifouling activity of the isolated compounds were also evaluated.     

Two new isoflavonoids from Bowdichia virgilioides

Two new isoflavonoids 7,8,4'-trimethoxyisoflavone and 7,8,4'-trimethoxyisoflavanone and calycosin (7,3'-hydroxy-4'-methoxyisoflavone) were isolated from the wood of the leguminous tree Bowdichia virgilioides by usual chromatographic procedures. Besides these compounds the pterocarpane (-)-maackianin, isoliquiritigenin (4,2',4'-trihydroxychalcone), and the hydrobenzylfurane derivative bowdenol were also obtained. The structures of these new compounds were determinated by MS and 1D and 2D NMR spectral analysis.     

Auroglaucin-related neuroprotective compounds from Vietnamese marine sediment-derived fungus Aspergillus niveoglaucus

Abstract

Two new auroglaucin-derived compounds, niveoglaucins A (1) and B (2), together with four known related compounds were isolated from extract of the marine sediment-derived strain of Aspergillus niveoglaucus. The structures of these compounds were determined by 1D and 2D NMR spectroscopy and high resolution MS. The plausible biosynthetic pathway was proposed for new compounds 1 and 2. The neuroprotective activity in 6-OHDA-induced Parkinson’s disease cell model was shown for niveoglaucin A (1).     

Two new isoaurones derivatives from Callistephus chinensis flower

Two new isoaurones derivatives were obtained from Callistephus chinensis flower. Their structures were elucidated on the basis of extensive spectroscopic analyses. Both of the new compounds were evaluated cytotoxic activity. Phytochemical investigation of Callistephus chinensis flower led to the isolation of two new isoaurones derivatives (Z)-4′,4,10-trihydroxy-siamaurone (1) and (E)-4′,4,10-trihydroxy-siamaurone (2). The structures of these new compounds were identified by the interpretation of spectroscopic data (mainly 1D and 2D NMR) and by comparison with data reported in the literature. Both of the new compounds were evaluated for their cytotoxicity.     

Resveratrol derivatives from Upuna borneensis

Four new resveratrol derivatives, upunaphenols B (1), C (4), D (5) (resveratrol tetramer) and E (6, resveratrol dimer with a C6-C1 unit), together with nine known resveratrol oligomers and resveratrol were isolated from an acetone soluble part of stem of Upuna borneensis (Dipterocarpaceae). The structures of new compounds were determined by spectral analysis including 1D and 2D NMR experiments.