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.     

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 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.     

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.     

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.     

New phenanthrene glycosides from Dendrobium denneanum and their cytotoxic activity

Five new phenanthrene glycosides, denneanosides A–E (1–5), and one new 9,10-dihydrophenanthrene glycoside, denneanoside F (6) were isolated from the stem of Dendrobium denneanum. The chemical structures of the new compounds were established on the basis of extensive spectroscopic data. The isolated compounds were evaluated for their in vitro cytotoxic activity against SNU387 hepatocellular carcinoma cell line. Compounds 1–3 showed moderate cytotoxic activities while compounds 4–6 showed weak activities.     

A new phenolic acid from Zanthoxylum nitidum var. tomentosum (Rutaceae) and its chemotaxonomic significance

A new compound, nitomentosin (1), along with sixteen known compounds (2–17), were isolated from Zanthoxylum nitidum var. tomentosum (Rutaceae). The structure of compound 1 including absolute configurations was determined by detailed spectroscopic information (HRESIMS and NMR) and from the electronic circular dichroism (ECD) spectra. From the present investigation, compound 3 is a new natural compound although it has been reported previously as a synthetic substance, and compound 15 is found for the first time in a plant. All these compounds except 2, 5–10 and 12 were isolated from Z. nitidum for the first time. Furthermore, the chemotaxonomic significance of the isolated compounds is discussed.     

Pyrrole alkaloids from the fruits of Morus alba

Phytochemical investigation of the fruits of Morus alba afforded seventeen pyrrole alkaloids including five new compounds. The structures of five new pyrrole alkaloids, named morroles B–F (4, 5, 7, 16 and 17), were determined on the basis of spectroscopic interpretations. 4-[Formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl]butanoate (2) was synthesized by chemical reaction but first isolated from nature. Among isolated compounds, compounds 6 and 14 significantly inhibited pancreatic lipase activity.     

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.     

Further chemical constituents from Sinningia canescens and S. leucotricha (Gesneriaceae)

Four new compounds were isolated from the tubers of Sinningia canescens and S. leucotricha: one naphthoquinone, 7-methoxy-8-hydroxy-α-dunnione (1); two arylbenzofurans, sinningial A (2) and B (3); and one sesquiterpene, 11-epi-subergorgiol (4). Seventeen additional known compounds were isolated and identified. The structures of all compounds were determined by spectroscopic and MS analysis.     

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.     

Cytotoxic metabolites from the leaves of the mangrove Rhizophora apiculata

One new 8,4’-oxyneolignan (1) and one new 7,8-dihydrobenzofuranone (2), together with twenty-one known compounds (3‒23) were isolated from the methanol extract of Rhizophora apiculata leaves. The structures of new compounds, as well as their absolute configuration, were determined by a combination of spectroscopic methods and quantum chemical calculations of NMR and ECD data. All isolated compounds were evaluated for their cytotoxicity, and only 2,6-dimethoxy-1,4-benzoquinone (8) exhibited inhibitory effects against SK-LU-1, HepG2, and MCF7 cells with IC₅₀ values in the range of 8.33–14.82 μM.     

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 calyces of Physalis alkekengi var. franchetii

One new monoterpenoid glycoside (1), together with seven known compounds, including two alkaloids (2–3), three phenylpropanoids (4–6), and two nucleosides (7–8) were isolated from the calyces of Physalis alkekengi var. franchetii. Their structures were elucidated by a combination of detailed spectroscopic analyses, chemical methods, and comparison with reported data. These eight compounds were isolated for the first time from the genus Physalis. The chemotaxonomic significance of these compounds was summarized.     

New sesquiterpenes from the endophyte Microdiplodia sp. TT-12 and their antimicrobial activity

Four new compounds, phomadecalin F (1), 8α-monoacetoxyphomadecalin D (2), 3-epi-phomadecalin D (3), and 13-hydroxylmacrophorin A (4), were isolated from the endophyte, Microdiplodia sp. TT-12 together with two known compounds, phomadecalins C (5) and D (6). The structures of the compounds were elucidated by NMR spectroscopic and mass spectrometric analyses in combination with chemical means. The antibacterial activities of the isolated compounds were evaluated. Compound 4 was weakly active against Raffaelea quercivora.     

Two new antioxidant flavones from the twigs of Eriosema robustum (Fabaceae)

Phytochemical study of the ethanol extract of the twigs of Eriosema robustum, a Cameroonian medicinal plant resulted to the isolation of two new flavones, 2′,3′,5′,5,7-pentahydroxy-3,4′-dimethoxyflavone (1) and 2′,3,5′,5,7-pentahydroxy-4′-methoxyflavone (2), along with five known compounds: 6-prenylpinocembrin (3), 1-O-heptatriacontanoyl glycerol (4), β-sitosterol (5), stigmasterol (6) and 3-O-β-d-glucopyranoside of sitosterol (7). The structure of the isolated compounds were elucidated on the basis of their NMR, UV and MS data, and by comparison with those reported in the literature. The ethanol crude extract, fractions and some isolated compounds (1–4) were evaluated for their radical scavenging capacity using 2,2-diphenyl-1-picryhydrazyl (DPPH). The crude extract, fraction II, the new compounds namely robusflavones A (1) and B (2) exhibited significant antioxidant activity.     

New antiproliferative and immunosuppressive withanolides from the seeds of Datura metel

Two new withanolides baimantuoluoside H (1) and baimantuoluoline K (2), and one known withanolide glycoside (3) were isolated and identified from the ethyl acetate-soluble fraction of ethanol extract of Datura metel seeds. The structures of the new compounds were determined using 1D and 2D NMR spectroscopy, and mass spectrometry. All isolated compounds were evaluated for their antiproliferative activity against human gastric adenocarcinoma (SGC-7901), human hepatoma (Hepg2), and human breast cancer (MCF-7) cells, as well as their immunosuppressive properties. It was determined that compounds 1–3 exhibited medium antiproliferative and potential immunosuppressive effects.     

A new chromane derivative from the stem bark of Scyphocephalium ochocoa

A new chromane, 5,8-dihydroxy-2-(10′-phenyldecyl)chroman-4-one (1) was isolated from the stem bark of Scyphocephalium ochocoa, along with three known compounds (2–4). The structure of compound 1 was determined with help of spectroscopic data including IR, UV, HREIMS, 1D and 2D NMR (COSY, HMQC and HMBC) experiments. Furthermore, the chemotaxonomic significance of these compounds along with other compounds previously isolated from Scyphocephalium ochocoa was discussed.     

Bioactive monoterpene indole alkaloids from Nauclea officinalis

Two new monoterpene indole alkaloids, naucleaoffines A (1) and B (2), together with six known alkaloids (3–8), were isolated from the stems and leaves of Nauclea officinalis. The structures of 1 and 2 were elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with the data reported in literature. All isolated compounds were evaluated for their anti-inflammatory activities and anti-HIV-1 activities. Compounds 1–8 exhibited significant inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro with IC₅₀ values comparable to that of hydrocortisone. In addition, compounds 1–8 showed significant anti-HIV-1 activities with EC₅₀ ranged from 0.06 to 2.08 µM. These findings suggest that the discoveries of these indole alkaloids with significant anti-inflammatory activities and anti-HIV-1 activities isolated from N. officinalis could be of great importance to the development of new anti-inflammatory and anti-HIV agents.     

Four new sesquiterpenes from the rhizomes of Curcuma wenyujin

Four new sesquiterpenes, namely wenyujinols I – L (1 – 4), along with eleven known ones were isolated from the rhizomes of Curcuma wenyujin. The structures of new compounds were elucidated using spectroscopic and spectrometric data analyses. All isolated compounds were evaluated for their inhibitory effects on melanin production and tyrosinase activity in B16F10 cells. Compound 1 exhibited significant inhibition against melanin production.