A new acorane sesquiterpenes of Lysionotus pauciflorus maxim. Form Guizhou province,China

A new acorane sesquiterpene (1), together with fourteen known compounds were isolated from the whole plant of Lysionotus pauciflorus Maxim. The chemical structures of the compounds were identified by physio-chemical properties and 1D-NMR, 2D-NMR, ESI-MS, IR and ECD spectra. Among them, six compounds (1, 4, 6, 7, 13, 15) were first found in the genus Lysionotus. The chemotaxonomic significance of the isolated compounds in the genus Lysionotus and family Gesneriaceae were discussed.     

A new meroterpenoid from endophytic fungus Talaromyces amestolkiae CS-O-1

Talaromyces amestolkiae CS-O-1, isolated from Tripterygium Wilfordii Hook. f., was identified based on its ITS and 18S rDNA gene sequencing. A new meroterpenoid, chrodrimanin T (1), along with six known compounds, nicotinamide (2), penipyridone D (3), penipyridone A (4), 3-benzylidene-8,8a-dihydroxy-2-methyl-hexahydro-pyrrolo[1,2-a]pyrazine-1,4-dione (5), butyl-isobutyl-phthalate (6), and aspergillumarin A (7), were isolated from Talaromyces amestolkiae CS-O-1. The structures and relative configurations of these compounds were established by the analysis of HRMS, 1D and 2D-NMR spectroscopy and the comparison with data in the literature. The compounds 2–6 were first isolated from Talaromyces genus. Herein, the chemotaxonomic significance of these compounds is described.     

A new bicyclic sesquiterpenoid from Merremia yunnanensis

A new sesquiterpenoid, 1α,4β,8β,9β-eudesmane-tetrol-1-O-β-D-glucopyranoside (1), together with nine known compounds (2–10), were isolated from Merremia yunnanensis. The structures of these compounds were elucidated by spectroscopic methods and compared to data in the literature. All these compounds (1–10) were firstly isolated from this plant, and compounds 3, 5, 7, and 10 were reported from the Merremia genus for the first time. The significance of the chemotaxonomy for these compounds is described herein.     

Chemical constituents from leaves of Cinnamomum subavenium

A new eudesmane sesquiterpene glycoside, 1α,6β-dihydroxy-5,10-bis-epi-eudesm-15-carboxaldehyde-6-O-β-d-Glucopyranoside (1), together with eleven known compounds (2–12) were isolated from the leaves of Cinnamomum subavenium Miq. Their structures were elucidated by a combination of spectroscopic data analysis and comparison with literature data. All compounds were isolated from C. subavenium for the first time. The chemotaxonomic significance of the isolated compounds was summarized.     

Caged xanthones displaying protein tyrosine phosphatase 1B (PTP1B) inhibition from Cratoxylum cochinchinense

Four new caged xanthones (1–4) and two known compounds (5, 6) were isolated from the roots of Cratoxylum cochinchinense, a polyphenol rich plant, collected in China. The structures of the isolated compounds (1–6) were characterized by obtaining their detailed spectroscopic data. In particular, compounds 1 and 6 were fully identified by X-ray crystallographic data. The isolated compounds (1–6) were evaluated against protein tyrosine phosphatase 1B (PTP1B), which plays an important role in diabetes, obesity, and cancer. Among these compounds, 3, 4, and 6 displayed significant inhibition with IC₅₀ values of 76.3, 43.2, and 6.6 µM, respectively. A detailed kinetic study was conducted by determining K_m, V_max, and the ratio of K_ik and K_iv, which revealed that all the compounds behaved as competitive inhibitors.     

Chemical constituents from the fruiting bodies of Xylaria euglossa Fr. and its chemotaxonomic study

Three anthracenones (1–3), two lactams (4–5), three sterols (6–8), one ceramides (9), one long-strain fatty acid (10) were isolated from the fruiting bodies of Xylaria euglossa Fr. All the compounds were isolated from this fungus for the first time. Compound 1, 4 and 5 were isolated from the family Xylariaceae for the first time. Compound 1 and 4–5 were considered chemotaxonomically significant for the species Xylaria euglossa.     

Chemical constituents from Euphorbia stracheyi Boiss

The chemical investigation of whole plants Euphorbia stracheyi Boiss. led to the isolation of 14 compounds, including eight diterpenes (1–8), one monoterpene (9), three coumarins (10–12), and two phenols (13–14). Their structures were elucidated by extensive spectroscopic analyses and by comparison with the literature. Compounds 1–6, and 8–12 were firstly isolated from E. stracheyi, while compounds 6, and 9 were isolated from Euphorbia genus for the first time. The chemotaxonomic significance of these isolated compounds is discussed.     

Phytochemical and chemotaxonomic study on Dianella ensifolia (L.) DC

Phytochemical investigation of the roots of Dianella ensifolia led to the isolation of eleven known compounds, including two aromatics (1, 2), two chromones (3, 4), and seven flavonoids (5–11). The structures of these compounds were elucidated on the basis of spectral analysis and comparison with data reported in literature. In the present research, all of the isolated compounds 1–11 were reported for the first time in the species D. ensifolia. Compounds 1–4 and 7–11 were firstly isolated from the genus Dianella. Compounds 1, 2, 8, and 9 have not been reported from any species in Liliaceae family. The chemotaxonomic significance of the isolated compounds was summarized.     

Monoterpenoid indole alkaloids from Palicourea crocea

A new monoterpenoid indole alkaloid N-oxide, 3,4-dihydro-1-(1-β-d-glucopyranosyloxy-1,4a,5,7a-tetrahydro-4-methoxycarbonylcyclopenta[c]pyran-7-yl)-β-carboline-N²-oxide (3) and two known monoterpenoid indole alkaloids, croceaine A (1) and psychollatine (2), were isolated from Palicourea crocea (Rubiaceae) from Trinidad. The structures of 1–3 were determined on the basis of spectral and other physical data. Compounds 1 and 2 were previously isolated from plants of different genera viz. Palicourea crocea and Psychotria umbellata, respectively, both collected in Brazil. The results support the proposal that the genus Palicourea and the subgenus Heteropsychotria should be combined into a single genus.     

Meroterpenoids from the fruiting bodies of higher fungus Ganoderma resinaceum

Phytochemical investigation on the fruiting bodies of Ganoderma resinaceum led to the isolation of five new meroterpenoids, namely ganoresinains A–E (1–5), and four known analogues (6–9). The new compounds were identified by extensive analyses of spectroscopic data (NMR, MS, UV, and IR) and comparison with the literature data. Compound 1 and 6 were isolated as enantiomeric mixture, which were separated over analytical chiral HPLC chromatography. Compounds 6–9 were isolated from G. resinaceum for the first time.     

Chemical constituents from Teucrium viscidum

A new guaiane sesquiterpenoid (1), two known guaiane sesquiterpenoids (2 and 3), and eleven known compounds (4–14), were isolated from Teucrium viscidum. Their structures were identified by spectroscopic analyses and by comparison of their spectral data with those reported in the literature. The absolute configuration of lipidiol (2) was determined by single-crystal X-ray diffraction analysis with Cu Kα radiation. Compounds 12 and 13 were isolated as natural products for the first time. All compounds were isolated from T. viscidum for the first time.     

New diplosporin and agistatine derivatives produced by the fungal endophyte Xylaria sp. isolated from Vitis labrusca

A Xylaria sp. was isolated as an endophyte from a surface-sterilized Concord grape leaf (Vitis labrusca). Dereplication and LC–MS analysis of the filtrate extracts identified two new structures, compound 1, 13-O-methyl-(5R) diplosporin, and 2 a new agistatine. Additionally, five known compounds 3–7 including an agistatine, coriloxin, (5R)-diplosporin, and two mellein derivatives were also isolated. This is the first report of these structurally-related metabolites isolated from the same fungus, suggesting they share a related biosynthesis. Metabolites were isolated using liquid chromatography-solid phase extraction (LC-SPE) and semi-preparative HPLC. Structures were elucidated on the basis of 1D and 2D NMR analysis, HRMS measurements and X-ray structural analysis for compound 1.     

A pair of new lignan enantiomers from Croton tiglium

A pair of new 3′,7-epoxy-8,4′-oxyneolignan enantiomers [(+)-1 and (−)-1] as well as a known phenylpropanoid (2) were isolated from the seeds of Croton tiglium Linn. Their structures were established based on extensive spectroscopic analyses. The absolute configurations of (+)-1 and (−)-1 were determined by NMR data calculations and electronic circular dichroism calculations. All compounds were isolated from the genus Croton for the first time. Particularly, (+)-1 and (−)-1 were the first 3′,7-epoxy-8,4′-oxyneolignanes reported in Croton. The chemotaxonomic significance of these compounds was discussed.     

Chemical constituents from Alnus mandshurica (Callier) Hand.-Mazz. and their chemotaxonomic significance

A new phenol compound, (9S)-9-hydroxy-9-[(2-hydroxyphenyl)methoxy]-nonanoic acid methyl ester (1) was isolated from the stem bark of Alnus mandshurica (Callier) Hand.-Mazz., along with eight known compounds (2–9). The structure of compound 1 was determined by spectral analyses, including HR-ESI-MS, 1D and 2D NMR (COSY, HMQC and HMBC) experiments. All the isolated compounds were reported for first time from A. mandshurica. Furthermore, compounds 3–9 were found in the family Betulaceae for the first time.     

Three new cucurbitane triterpenoids from Hemsleya penxianensis and their cytotoxic activities

Two new cucurbitane glycosides, hemslepenside A (1) and 16,25-O-diacetyl-cucurbitacin F-2-O-β-d-glucopyranoside (3), one new cucurbitacin, 16-O-acetyl-cucurbitacin F (2), along with three known cucurbitane compounds, were isolated from the roots of Hemsleya penxianensis. The structures of 1–6 were established on the basis of extensive spectroscopic and chemical methods. The isolated compounds were evaluated for their cytotoxic activities against different three human cancer cell lines, with IC₅₀ values in the low microgram range.     

Chemical constituents from starfish Culcita novaeguineae

Seven polyhydroxylated steroidal glycosides (1–7) and two polyhydroxylated sterols (8, 9) were isolated and identified from the 75% ethanol extract of starfish Culcita novaeguineae which was collected in Xisha Islands of South China Sea. The structures of the isolated compounds were elucidated on the basis of spectroscopic data, physical and chemical evidence, MS spectrum and assisted by comparison with the reported data. To the best of our knowledge, this is the first time to report compounds 1–6, 8 and 9 from genus Culcita. Moreover, compounds 1, 4–6, 8 and 9 were isolated from family Oreasteridae for the first time. And the chemotaxonomic significance of the isolated compounds was discussed.     

New cis-ent-clerodanes from Linaria japonica

Five new cis-ent-clerodanes, linarenones A–E (1–5) and two known compounds (6 and 7) were isolated from whole plant of Linaria japonica. The structures of these compounds were determined by various spectroscopic analyses (UV, IR, HR–ESI–MS, 1D and 2D NMR). The absolute configuration of five new diterpenoids was confirmed by circular dichroism (CD) analysis and chemical conversion. Cytotoxicity of the isolated compounds against A549 cell lines and Leishmania major were evaluated. The new cis-ent-clerodane 3 was found to be moderately active against A549 cell lines, and new cis-ent-clerodanes 1, 6 and desacetyl-linarienone (7) were active against L. major.     

Chemical constituents from the whole plant of Liparis japonica

A new lignanoid (1), together with six known lignanoids (2–7) and four known flavonoids (8–11), were isolated from the EtOAc extract of Liparis japonica. Their structures were determined by analyzing the HRESIMS, NMR, CD spectroscopic data, and comparing with the reported literatures. Among them, 1 was a new compound, 2–11 were first isolated from L. japonica and the genus of Liparis. The chemotaxonomic significance of these isolates was comprehensively discussed.     

Chemical constituents of Peperomia tetraphylla (Forst. F.) Hooker et Arnott

Sixteen compounds were isolated from the whole herbs of Peperomia tetraphylla (Forst. F.) Hooker et Arnott by phytochemical methods, including eight flavonoids (1–3, 6, 7, 14–16), three lignans (8–10), three beta sitosterols (4, 5, 11), and two phenolic acids (12, 13). Their structures were identified by the analysis of NMR and MS, as well as the comparisons to the reported data. Among them, 2″-O-xylosylisoswertisin (14) was firstly isolated from the Piperaceae family, as well as ten compounds (1–4, 7, 10–11, 13, 15–16) were isolated from P. tytraphylla for the first time. Moreover, the chemotaxonomic significance of constituents isolated from P. tytraphylla was also discussed.     

Chemical constituents from Ailanthus altissima (Mill.) Swingle and chemotaxonomic significance

Sixteen compounds were isolated from the root barks of Ailanthus altissima (Mill.) Swingle, including thirteen lignans (1–13), two coumarins (14–15), and one chalcone (16). This is the first report on the occurrence of compounds 1–16 in the genus Ailanthus. Their structures were elucidated on the basis of NMR spectroscopic data. The plant distribution network of all isolated compounds was described to illustrate the significance of taxonomy. The presence of these congenetic lignans (1–13) and their biosynthetic relationships may be used for identification of Ailanthus genus.