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A new pentacyclic triterpene 3-O-β-(E)-(4-O-acetylferuloyl)-lupeol (1) possessing an unusual (E)-acetylferuloyl moiety at C-3 and a new bicoumarin 7,7′-dimethoxy-6,6′-dicoumarinyl ether (2) were isolated from the liana Landolphia lucida K. Schum, along with fourteen previously known compounds 3-16, where methandriol dipropionate (3) and 2,3-bis-(4-hydroxy-3-methoxy-benzyl)-dimethyl- succinate (5) were obtained for the first time from natural sources. The structures of the new compounds were established on the basis of extensive 1D and 2D NMR spectroscopy, and HRMS data analyses. The absolute configuration of 1 was determined by circular dichroism (CD) spectroscopy. Furthermore, compounds 1 and 2 had exhibited a significant antibacterial activity against Escherichia coli (ATCC 25922) with MIC values of 2.3 μM and 4.6 μM, respectively; while compounds 4 and 5 showed antiglycation and α-glucosidase inhibitory activities.

A new cerebroside, Contortamide (1) together with nine known compounds spegatrine (2), affinisine (3), Nb-methylaffinisine (4), ursolic acid (5), α-amyrin (6), bauerenol acetate (7), lupeol (8), be...

Three new alkaloids, janetinine (1a), pleiokomenine A (2), and huncaniterine B (3a), and 13 known compounds, pleiomutinine (3b), huncaniterine A (3c), 1-carbomethoxy-β-carboline (4), evoxanthine (5), deformyltalbotine acid lactone (6), pleiocarpamine (7), N4-methyl-10-hydroxygeissoschizol (8), spegatrine (9), neosarpagine (10), aspidofractinine (11), N1-methylkopsinin (12), pleiocarpine (13), and N1-methylkopsinin- N4-oxide (14), were isolated from the stem bark of Pleiocarpa pycnantha. Janetinine (1a) is a carbazole alkaloid; in pleiokomenine A (2), two aspidofractinine-type alkaloids are bridged by a methylene unit in an unprecedented way, and huncaniterine B (3a) is a pleiocarpamine-aspidofractinine-type dimer. The structures and relative configurations of these compounds were elucidated on the basis of NMR and MS analyses. Their absolute configurations were defined by means of experimental and calculated ECD data, and additionally, the structures of 5 and 13 were determined by single crystal X-ray diffraction. Compounds 1a, 2, 3b, 4, 6, 9, and 12 displayed cancer chemopreventive properties through either quinone reductase induction ( CD = 30.7, 30.2, 29.9, 43.5, and 36.7 μM for 1a, 4, 6, 9, and 12, respectively) and/or NF-κB inhibition with IC50 values of 13.1, 8.4, 9.4, and 8.8 μM for 2, 3b, 6, and 12, respectively.

In the 1H NMR-guided fractionation of extracts from the edible mushroom Lactarius deliciosus, two new azulene-type sesquiterpenoids, 7-isopropenyl-4-methyl-azulene-1-carboxylic acid (1) and 15-hydroxy-3,6-dihydrolactarazulene (2), together with seven known compounds were characterized. Their structures were determined on basis of spectroscopic evidence, as well as by comparing with literature data. Amongst the known metabolites, the 13C NMR assignment of 15-hydroxy-6,7-dihydrolactarazulene (3) is reported here for the first time. Moreover, 7-acetyl-4-methylazulene-1-carbaldehyde (5) displayed a moderate antibacterial activity against Staphylococcus aureus. Graphical Abstract *Digital image of L. deliciosus. Retrieved March 17, 2017 from https://upload.wikimedia.org/wikipedia/commons/e/e3/Lactarius_deliciosus_1_(1).jpg . Electronic supplementary material The online version of this article (doi:10.1007/s13659-017-0130-1) contains supplementary material, which is available to authorized users.

An investigation of compounds extracted from Ochna schweinfurthiana roots with ethyl acetate led to the isolation of three new compounds 4⿴-methoxylophirone A ( 1 ), 4,4⿲,4⿴⿿trimethoxylophirone A ( 2 ) and (4 E ;7 Z )-3,8-dicarboxy-1-( O -β- d -glucopyranosyl-(1 ⿿ 6)- O -β- d -glucopyranosyl-2,9-dihydroxyhexeicosa-4,7-diene ( 3 ). Six known compounds were also identified, including Calodenone ( 4 ), Calodenine B ( 5 ), Lophirone A ( 6 ), Gerontoisoflavone A( 7 ), 16α,17-dihydroxy- ent -kauran-19-oic acid ( 8 ) and 3β- O - d -glucopyranosyl-β-sitosterol ( 9 ). This report describes the first time that compounds 4 - 8 have been isolated from this plant, while 8 has never been identified in the genus Ochna . Some of the isolated compounds were evaluated for their antiplasmodial activity against the chloroquine-sensitive Plasmodium falciparum strain 3D7 and antioxidant activity using DPPH radical scavenging and Ferric reducing-antioxidant power (FRAP) assays. Compound 5 exhibited prominent radical scavenging and FRAP activities, while 7 had weak activity. Compound 1 showed good in vitro anti-plasmodial activity. The structures of the isolated compounds were elucidated by spectroscopic methods and comparisons with prior data in the literature.

Two bisindoline alkaloids, contortarine A, 16-epi-pleiomutinine and a reaction product of pleiomutinine, namely N4-chloromethyl-pleiomutinine, were isolated from the roots of Tabernaemontana contorta Stapf. together with five known compounds: pleiomutinine, 1-carbomethoxy-β-carboline, strictosidine lactam, pleiocarpamine, and pleiocarpine. The structures and relative configuration of these alkaloids were determined by extensive 1D and 2D NMR, and MS measurements. The absolute configuration of these compounds was determined by comparison of experimental and calculated ECD spectra. Among the isolated compounds, contortarine A, 1-carbomethoxy-β-carboline and strictosidine lactam presented cancer chemopreventive properties through either quinone reductase (QR) induction with CD values of 16.0 ± 2.5, 30.2 ± 6.1 and 23.1 ± 4.6 μM, respectively, while pleiomutinine and 16-epi-pleiomutinine displayed the inhibition of TNF-α induced NF-κB activity with IC50 at 11.7 ± 2.6 and 3.4 ± 1.1 μM, respectively.

From the leaves and stem bark of Campylospermum flavum (Ochnaceae), three compounds, namely 4‴-O-methylagathisflavone, flavumchalcone, and flavumindole have been isolated together with 10 known compounds, including three flavonoids, two biflavonoids, two alkaloids, two nitrile glucosides, and glucopyranosyl-β-sistosterol. The structures of these compounds and their relative configurations were established by 1D and 2D NMR experiments. The methanolic crude extracts of leaves and stem bark of C. flavum and compounds displayed a significant cytotoxicity towards Artemia salina larvae.

Seven flavonoids, hemerocallone (1), 6,7-dimethoxy-3′,4′-dimethoxyisoflavone (2), amentoflavone (4), agathisflavone (6), cupressuflavone (8), robustaflavone (9) and epicatechin (10), together with three other compounds, lithospermoside (3), β-D-fructofuranosyl-α-D-glucopyranoside (5) and 3β-O-D-glucopyranosyl-β-stigmasterol (7), were isolated from the ethyl acetate extract of the stem bark of Ochna schweinfurthiana F. Hoffm. All the compounds were characterised by spectroscopic and mass spectrometric methods, and by comparison with literature data. Cytotoxicity of the extracts and compounds against cervical adenocarcinoma (HeLa) cells was evaluated by MTT assay. Compounds 4 and 6 exhibited good cytotoxic activity, with IC50 values of 20.7 and 10.0 μM, respectively.

International audience; Two new flavone glycosides, 3 ''-O-acetyl-7-O-methylvitexin (1) and 6 ''-alpha-rhamnopyranosyl-7-O-methylvitexin (2), along with nine known compounds (3-11) were isolated from the leaves of Rhabdophyllum arnoldianum (Ochnaceae). The structures of the new compounds were established by detailed spectroscopic studies and mass spectrometry, while known compounds were characterised by direct comparison of their reported NMR data with those found in the literature. All these compounds were the first reported from Rhabdophyllum genus. The biological assays on crude extracts and compounds of this plant demonstrated that the crude extracts possess significant antimicrobial activity against Gram-positive bacteria.

Phytochemical investigation of the leaves of Sorindeia juglandifolia A. Rich. led to the isolation and identifi cation of a new C-glucosylfl avone, 2´´,6´´-di-O-acetyl-7-O-methyl vitexin (1), together with seven known compounds, 2´´-O-acetyl-7-O-methyl vitexin (2), mearnsitrin (3), robustafl avone (4), 3-O-galloyl catechin (5), tachioside (2-methoxy-benzene-1,4-diol-1- O-β-glucopyranoside) (6), 3β-O-D-glucopyranosyl-β-stigmasterol (7), and methyl gallate (8). The structures of 1 and the known compounds were established by IR, UV, MS, 1D, and 2D NMR spectra and by comparison with those of related compounds.