Picrachinentins A-F (-, respectively), six novel cyclopeptide alkaloid-type burpitides (CPABs), were isolated and fully elucidated from the EtOH extract of the stems and leaves of . Structurally, compounds - have a 14-membered paracyclophane ring system that was closed through an ether bond between the β-hydroxy amino acid and tyrosine and modified with a 4,5-methylenedioxybenzoyloxy (MDBz, and ) or hexanoyl (Hexa, , , , and ) group at the N-terminus. Interestingly, this is the first report on the isolation and characterization of CPABs from plants of the Simaroubaceae family.
View Article and Find Full Text PDFSeven undescribed polyoxygenated ursane-type triterpenoids (vitnegundins A-G), three undescribed triterpenoid saponins (vitnegundins H-J), and 17 known ones were isolated from an EtOH extract of the aerial parts of Vitex negundo L. The structures of the undescribed compounds were established by extensive spectroscopic analysis. The absolute configurations of vitnegundins A, B, and E were determined by single-crystal X-ray diffraction data.
View Article and Find Full Text PDFThree undescribed sesquiterpenes, designed as pichinenoid A-C (1-3), along with nine known ones (4-12) were isolated from the stems and leaves of Picrasma chinensis. The new isolates including their absolute configurations were elucidated based on extensive spectroscopic methods, single crystal X-ray diffraction, and electronic circular dichroism (ECD) experiments, as well as comparison with literature data. Structurally, compounds 1 and 2 are descending sesquiterpenes, while pichinenoid C (3) is a rare sesquiterpene bearing a 2-methylenebut-3-enoic acid moiety at the C-6 side chain.
View Article and Find Full Text PDFPhytochemical investigation on the aerial parts of Gnetum parvifolium led to the isolation of 15 new and eight known structurally diverse stilbenes. The isolated compounds comprised (E)- or (Z)-stilbene (1-6, 15-20), dihydrostilbene (21), phenylbenzofuran (7, 8, 22), benzylated stilbene (9-11), benzylated stilbene dimer (12), and nitrogen-containing stilbene (13a, 13b, 14) types. The structures of the new compounds (1-12, 13a, 13b, 14) were established through spectroscopic analyses and experimental and calculated ECD data.
View Article and Find Full Text PDFTwenty-six clerodane diterpenoids have been isolated from T. sagittata, a plant species of traditional Chinese medicine Radix Tinosporae, also named as "Jin Guo Lan". Among them, there are eight previously undescribed clerodane diterpenoids (tinotanoids A-H: 1-8), and 18 known diterpenoids (9-26).
View Article and Find Full Text PDFA total of 17 structurally diverse clerodane diterpenoids, including ten undescribed clerodane diterpenoids (tinopanoids K-T, 1-10) and seven known compounds (11-17), were isolated from the vines and leaves of Tinospora crispa. Compound 3 has not only bear the dominant substituents of γ-hydroxy-α, β-unsaturated-γ-lactone with anti-inflammatory activity, but also a ternary epoxy structure at C-3/C-4. The planar structures and relative configurations of the clerodane diterpenoids were elucidated by spectroscopic data interpretation.
View Article and Find Full Text PDFFive new polychlorinated bibenzyls (1-5) along with 3 known compounds (6-8) were isolated from the stems and leaves of Rhododendron minutiflorum. The chemical structures of all the isolates were determined by spectroscopic methods, and compounds 1 and 2 were further verified by single-crystal X-ray diffraction analyses. Compounds 1-5 were halogenated compounds which bear three to five chlorine atoms in their chemical structures.
View Article and Find Full Text PDFFive undescribed triterpenoids, two unusual omphalane-type sesquiterpenoids together with twenty-five known compounds were isolated from the leaves and stems of Rhododendron minutiflorum Hu. The absolute configurations of 1-3 and 6 were established by single-crystal X-ray diffraction analysis and electronic circular dichroism (ECD). Compounds 6-7 feature the rare omphalane-type sesquiterpene skeleton and are verified by single-crystal X-ray diffraction analysis for the first time.
View Article and Find Full Text PDFSix new lignans with various type of linkage between two C6-C3 fragments (1a, 1b, 2a, 2b, 3, 4), two new meroterpenoids (5, 6) and 24 known compounds (7-30) were isolated from an EtOH extract of the stems and leaves of Piper puberulum. The absolute configurations of enantiomers 1a and 1b were determined by single-crystal X-ray diffraction analysis, 2a and 2b were determined by comparing their calculated and experimental ECD spectra. Biogenetically, all the new lignans may come from the polymerization of two molecules of hydroxychavicol (30).
View Article and Find Full Text PDFSixteen chebulic acid derivatives, including nine new (1-9) and seven known (10-16) ones, were isolated from an ethanol extract of the branches and leaves of Balakata baccata. The structures of the new compounds were elucidated by their UV, IR, HRESIMS, NMR, electronic circular dichroism (ECD) and single-crystal X-ray diffraction data. The effects of all the isolates on antineuroinflammatory and antioxidant activities were evaluated.
View Article and Find Full Text PDFThree new tyramine-type alkamides (-), three new natural products (-), five new -acylated/formylated aporphine alkamides with different ratios of rotational isomers (-), and 20 known alkamides (-) were isolated from an EtOH extract of the stems and leaves of . The absolute configurations of compounds , , and were determined by single-crystal X-ray diffraction analysis. In the biological activity assay, compounds , , and - displayed inhibitory effects against lipopolysaccharide-induced NO release in BV-2 microglial cells, exhibiting IC values of 0.
View Article and Find Full Text PDFTwo pairs of cycloneolignane enantiomers, piperhancins A and B ( and , respectively), along with two enantiomeric pairs of biosynthetic related neolignanes, hancinone C () and piperhancin C (), were isolated from the stems of . Compound is an unprecedented 1',2:1,2'-dicyclo-8,3'-neolignane. Their structures and absolute configurations were elucidated by spectroscopic analyses, X-ray diffraction, and electronic circular dichroism calculations.
View Article and Find Full Text PDFFive new flavonol glycosides (1-5), one new phenylpropanoid glycoside (6), and nine known glycosides (7-15) were isolated from the stems and leaves of Neoshirakia japonica. The structures of the new compounds were determined by detailed analysis of spectroscopic data (HRESIMS, 1D and 2D NMR) and acid hydrolysis experiment. The antineuroinflammatory effects of all the isolates were evaluated by inhibiting NO production against LPS-induced BV-2 microglial cells.
View Article and Find Full Text PDFFour new diterpenoids (1-4), three new triterpenoids (12-14), and seven known diterpenoids (5-11) were obtained from an aqueous EtOH extract of the aerial parts of Triadica rotundifolia. The structures of new compounds were determined by spectroscopic techniques. Their absolute configurations were verified via single-crystal X-ray diffraction data, Mo(OAc) induced electronic circular dichroism (ECD), and ECD calculations.
View Article and Find Full Text PDFTwenty new chebulic acid and brevifolincarboxylic acid derivatives, including eight optically pure or achiral compounds (- and ) and six pairs of enantiomers (/-/), along with nine known analogues (-), were isolated from an EtOH extract of the aerial parts of . The absolute configurations of the new compounds were assigned based on single-crystal X-ray diffraction analysis and comparison of the experimental and calculated ECD data. Racemic or scalemic mixtures of - were isolated, and their enantiomers were analyzed by chiral-phase HPLC-ECD measurements.
View Article and Find Full Text PDFInflammation is a very common and important basic pathological process. There is still a great need for the isolation of effective anti-inflammatory agents from plants. In this paper, five new isobutylamides, zanthoxylumamides E-I (1-5), and four known isobutylamides (6-9) were isolated from Zanthoxylum nitidum var.
View Article and Find Full Text PDFOne new pseudoguaianolide (1), one new megastigmane (6), and one new ent-abietane diterpene (9), together with seven known compounds (2-5, 7, 8, and 10) were isolated from the aerial parts of Euphorbia thymifolia. The structures of the new compounds and their relative configurations were determined by spectroscopic data analysis. The absolute configurations of compounds 1, 6, and 9 were determined by single-crystal X-ray crystallographic analysis, modified Mosher's method and calculated ECD experiment, respectively.
View Article and Find Full Text PDFTwo previously undescribed guaiane-type sesquiterpenes (1 and 2), a pair of new salvialane-type sesquiterpenes (3a and 3b), together with 11 known compounds were isolated and purified from the rhizomes of Curcuma kwangsiensis. Their structures were elucidated by the extensive spectroscopic data (1D- and 2D-NMR) analysis. All the isolated compounds were assessed for their anti-neuroinflammatory activity by inhibiting the nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine BV-2 microglial cells in vitro assay, and the isolates 3 and 11 showed anti-neuroinflammatory activity with IC values of 1.
View Article and Find Full Text PDFTwo new coumarinolignoids, sapiumins D (1) and E (2), a new lignanoid, lariciresinol 9'-benzoate (3), together with six known coumarinolignoids (4-9) and eight known lignanoids (10-17), were isolated from the stems and leaves of Sapium discolor. The structures of the isolated compounds were elucidated by extensive spectroscopic methods, including NMR, MS, and single crystal X-ray diffraction experiments. Compounds 5, 10, 11, and 13 significantly inhibited nitric oxide production in lipopolysaccharide-induced BV-2 microglial cells, with IC values in the range of 2.
View Article and Find Full Text PDFSeventeen compounds, including three new pairs of coumarinolignoid enantiomers, (7' S,8' S)-sapiumins A-C (1a-3a) and (7' R,8' R)-sapiumins A-C (1b-3b), six new taraxerane triterpenoids, sapiumic acids A-F (4-9), and five known taraxerane triterpenoids (10-14), were isolated from an ethanol extract prepared from the stems and leaves of Sapium discolor. The structures of 1-9 and their relative configurations were determined by spectroscopic data analysis, and the absolute configurations of the coumarinolignoids 1a/1b-3a/3b and triterpenoids 6-9 were assigned using experimental and calculated ECD data. Compounds 1a/1b-3a/3b are the first coumarinolignoids to be reported from the genus Sapium.
View Article and Find Full Text PDFTwo new cadinane sesquiterpene glucosides (1, 2), two new phenylpropanoid glycosides (3, 4), and two new diterpenoid glucosides (5, 6), as well as 6 known compounds were isolated from the stems of Tinospora sinensis. The structures of these compounds were elucidated by extensive spectroscopic analysis and chemical methods. The absolute configuration of compound 1 was determined by timedependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations and in situ dimolybdenum CD method.
View Article and Find Full Text PDFThe chemical constituents from the ethanol extract of Clerodendrum japonicum were isolated by a combination of various chromatographic techniques including column chromatography over silica gel, sephadex LH-20, ODS and reversed phase HPLC. Sixteen compounds with a pair of epimers were elucidated through the application of physicochemical properties with modern spectral analysis technology as 7α-hydroxy syringaresinol (1), (-)-syringaresinol (2), (-)-medioresinol (3), 2″,3″--acetylmartyonside (4), 2″--acetyl-martyonside (5), martinoside (6), monoacetyl martinoside (7),cytochalasin O (8), 9-epi-blumenol B (9), (6R, 9S) and (6R,9)-9-hydroxy-4-megastigmen-3-one (10a,10b), (6R,9S)-3-oxo-α-ionol (11), (-)-dehydrovomifoliol (12),megastigm-5-en-3,9-diol (13), (3R,6E,10S)-2,6,10-trimethyl-3-hydroxydodeca-6,11-diene-2,10-diol (14), (2)-butylitaconic acid (15), 3-(3&-hydroxybutyl)-2,4,4-trimethylcyclohexa-2,5-dienone (16), (-)-loliolide (17), of which compound 1 and 15 are new natural product, the other compounds were isolated for the first time from Clerodendrum japonicum except for compounds 4, 6 and 7.
View Article and Find Full Text PDFSix previously undescribed oleanane-type triterpenoid saponins, fortunosides A-F, together with six known ones, were isolated from the aerial parts of Lysimachia fortunei Maxim. Their structures were established by spectroscopic data analyses (1D, 2D-NMR and HRESIMS) and chemical methods. All isolated triterpenoid saponins were evaluated for their cytotoxicity against four human liver cancer cell lines (SMMC-7721, Hep3B, HuH7, and SK-Hep-1).
View Article and Find Full Text PDFFive previously undescribed monoterpenoid indole alkaloids, mappianines A-E, along with twelve known analogues, were isolated from the stems of Mappianthus iodoides Hand.-Mazz. Their structures and absolute configurations were determined by spectroscopic analysis, single-crystal X-ray diffraction, and ECD calculations.
View Article and Find Full Text PDFChemical investigation on the aerial parts of Rhododendron capitatum resulted in the discovery of five enantiomeric pairs of new meroterpenoids, (+)-/(-)-rhodonoids C (1a and 1b), E (3a and 3b), F (4a and 4b), and (-)-/(+)-rhodonoids D (2a and 2b) and G (5a and 5b). These enantiomeric pairs existed as partial racemates in a plant and were obtained by chiral HPLC separation. Their structures with absolute configurations were assigned by spectroscopic data, single-crystal X-ray diffraction, and ECD analysis.
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