Search

Three new 14-noreudesmane sesquiterpenes ( 1 ⿿ 3 ) as well as four known ones ( 4 ⿿ 7 ) were isolated from the leaves of Nicotiana tabacum . Their structures were determined mainly by spectroscopic methods, including extensive 1D- and 2D NMR techniques. Compounds 1⿿7 were evaluated for their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compound 1 exhibited moderate anti-TMV activity with inhibition rate of 46.7%, which were higher than that of positive control (ningnanmycin).

Lancolide E (1) featuring a complex tetracyclo[5.4.0.0(2,4).0(3,7)]undecane-bridged system that is constructed by an eight-, a three-, and two five-membered carbon rings in a sterically congested region was obtained in trace amounts from a "talented" schinortriterpenoid producer Schisandra lancifolia. Its structure was fully characterized by combining 2D NMR spectroscopy, theoretical calculations, and X-ray diffraction analysis. The biogenetic pathway of 1 was proposed to involve a Prins cyclization.

Three new isolates (1−3) including one new sterol and two new flavonoids together with three known sterols (4−6) were isolated from the leaves of Nicotiana tabacum. Their structures were determined mainly by spectroscopic methods, including extensive 1D and 2D NMR techniques. All compounds were evaluated for their anti-tobacco mosaic virus and cytotoxic activities. The results showed that compounds 2 and 3 exhibited high anti-TMV activity with inhibition rate of 34.2 and 33.4%, respectively, which were roughly equivalent to that of positive control. The cytotoxicities of compounds 1 and 4–6 against five human tumour cell lines were also tested, and tested compounds showed weak inhibitory activities against some tested human tumour cell lines.

Five new biphenyls, tababiphenyls A-E (1-5), together with five known ones (5-10), were isolated from the leaves of Nicotiana tabacum, of which compound 1 possessed a seldom reported 6-carbons unit in biphenyls. Their structures were established on the basis of extensive spectroscopic analyses. All compounds were tested for their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compounds 3 and 5 exhibited high anti-TMV activities with inhibition rate of 48.4% and 32.1%, respectively, which were higher than that of positive control (ningnanmycin). The other compounds also showed potential anti-TMV activities with inhibition rates in the range of 18.6-28.7%, respectively. (C) 2014 Elsevier B.V. All rights reserved.

Three new phenolic amides, tabamides A-C (1-3), together with three known phenolic amides (4-6), were isolated from the leaves of Nicotiana tabacum. Their structures were elucidated by spectroscopic methods, including extensive 1D- and 2D NMR techniques. Compounds 1-6 were also tested for their anti-tobacco mosaic virus (anti-TMV) activity. The results showed that compound 1 exhibited high anti-TMV activity with inhibition rate of 38.6%, which is higher than that of positive control (ningnanmycin). The other compounds also showed potential anti-TMV activity with inhibition rates in the range of 15.3-26.5%, respectively. (C) 2014 Published by Elsevier B.V. on behalf of Phytochemical Society of Europe.

Six new lignans (1-6), as well as five known ones (7-11) were isolated from the leaves and stems of Schisandra chinensis. The structures of 1-6 were established on the basis of spectroscopic methods including 1D-and 2D-NMR techniques and CD experiments. Compound 1 was the first example of naturally occurring N-containing lignans featuring a nicotinoyl group. All the new compounds were evaluated for their anti-HIV-1 activities and showed EC50 values in the range 17.89-138.23 mu g/mL.

Five new nortriterpenoids, schicagenins D-F (1-3, resp.) and negleschidilactones A and B (4 and 5, resp.), together with eleven known ones, were isolated from the stems of Schisandra neglecta. Their structures were established on the basis of extensive spectroscopic analyses. All the compounds were evaluated for their activities regarding insulin sensitivity in 3T3-L1 differentiated adipocytes. None of them showed a significant bioactivity at 10M concentration.

Six new lignans, schisphenlignans F-K (1-6), together with ten known ones, were isolated from the leaves and stems of Schisandra sphenanthera. Their structures were elucidated on the basis of spectroscopic methods, including extensive NMR, MS and CD spectra. In addition, some compounds were tested for their acute activity on insulin sensitivity in 3T3-L1 differentiated adipocytes and anti-HIV-1 activity. (C) 2013 Elsevier B.V. All rights reserved.

Four new indole alkaloids, plasiaticines A-D (1–4), together with two known ones, were isolated from the seeds of Plantago asiatica. The structures of the new compounds were elucidated on the basis of comprehensive analysis of spectroscopic data. All compounds were tested for their cytotoxic activity, and all compounds except 4 were tested for their acetylcholinesterase (AChE) inhibitory activities.

Two new neolignans, manneoinsigins A (1) and B (2), together with four known lignans, were isolated from the leaves and stems of Manglietia insignis. The new compounds were established on the basis of extensive spectroscopic analyses. All compounds except 2 were tested for their cytotoxic activity. Compound 3 showed weak cytotoxic activity against the HL-60 human tumor cell line with the IC50 value of 23.5 µM.

Three unreported sesquiterpenes possessing two new skeletons, tabasesquiterpenes A-C (1-3), together with three known sesquiterpenes (3-6) were isolated from the leaves of Nicotiana tabacum. Their structures were determined mainly by spectroscopic methods, including extensive 1D- and 2D-NMR techniques. Compounds 1-6 were evaluated for their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compound 2 exhibited high anti-TMV activity with inhibition rate of 35.2%, which were higher than that of positive control (ningnanmycin). The other compounds also showed potential anti-TMV activity with inhibition rates in the range of 20.5-28.6%.

Six new lignans (I), (II), (III), and (IV) are isolated along with five known ones from the leaves and stems of Schisandra chinensis.

A pair of new triterpenoid epimers, kadcoccitones A (1) and B (2), together with a new biogenetically related compound kadcoccitone C (3), were isolated from Kadsura coccinea. The epimers featured an unprecedented carbon skeleton with a 6/6/5/5-fused tetracyclic ring system unit and a C(9) side chain. Their structures were determined by spectroscopic data, ECD calculation, and single-crystal X-ray diffraction. Compounds 1 and 3 showed anti-HIV-1 activity with an EC(50) value of 47.91 and 32.66 μg/mL, respectively.

Four new compounds, a dibenzylbutane lignin, plasiaticine F (1), an acetylenic glycoside, plasiaticine G (2), an indole alkaloid, plasiaticine H (3), and an ionone derivative, plasiaticine I (4), were isolated from the seeds of Plantago asiatica. The structures of the new compounds were elucidated on the basis of comprehensive analysis of spectroscopic data. Compounds 1–3 were tested for their cytotoxicity, but lacked significant activity.

Four new compounds, maninsigins A-D (1-4), including two new neolignans (1-2) and two new sesquiterpenes (3-4), as well as ten known compounds (5-14), were isolated from the leaves and stems of Manglietia insignis. Their structures were established on the basis of extensive spectroscopic analyses. In addition, some compounds were tested for their cytotoxic and neurite outgrowth-promoting activities, as well as their antagonistic activity toward FXR ligand. (c) 2012 Elsevier B.V. All rights reserved.

Ten new triterpenoids, schiglausins A-J (1-10), as well as four known compounds, were isolated from the stems of Schisandra glaucescens. Their structures were elucidated on the basis of spectroscopic methods, including extensive NMR spectra and CD experiment. Compound 8 was determined to be a norlanostane triterpenoid. The crystal structure of compound 1 has been determined using single-crystal X-ray analysis while its absolute configuration was assigned on the basis of the CD spectrum. All isolates were tested for their FXR agonistic and antagonistic effects.

Three new dibenzocyclooctadiene lignans, marlignans M–O (1–3), together two known ones, were isolated from the leaves and stems of Schisandra wilsoniana. The structures of 1–3 were elucidated by spectroscopic methods, including extensive 1D- and 2D-NMR techniques. Compound 2 showed anti-HIV-1 activity with an EC50 value of 5.82 μg/mL and a therapeutic index (TI) of more than 12.8. Compound 3 showed obvious bioactivity in inhibiting Epstein-Barr virus early antigen (EBV-EA) activation.