Lignans from Schisandra propinqua var. propinqua

Two new dibenzocyclooctadiene lignans angeloyl-(+)-gomisin K(3) (1) and methylisogomisin O (2), together with six known ones, isogomisin O, angeloylisogomisin O, gomisin O, angeloygomisin O, benzoylgomisin O, epigomisin O, and four 1,4-bis(phenyl)-2,3-dimethylbutane type lignans, pregomisin, meso-dihydroguaiaretic acid, isoanwulignan, and sphenanlignan were isolated from the aerial parts of Schisandra propinqua var. propinqua. The structures of 1 and 2 were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques.     

五脂酮A, B和Butyryl Binankadsurin A的分离与结构

从采自广西柳州地区融水县的一种南五味子(Kadsurasp.)种子中分得三个已知化合物---binankadsurinA(1),acetylbinankadsurinA(2),angeloylbinankadsurinA(3)及三个新化合物---五脂酮(schisanlignone)A(4),B(5),butyrylbinankadsurinA(6)。它们的结构由光谱分析和化学转化而阐明。1系首次从自然界分得。在抗癌药理筛选中,4与5在体外都对白血病P-388细胞有抑制作用。其IC~5~0分别为10和40μg/mL。     

Complete assignments of 1H and 13C NMR data for seven arylnaphthalide lignans from Justicia procumbens

Three new arylnaphthalide lignans named 6'-hydroxy justicidin A (1), 6'-hydroxy justicidin B (2) and 6'-hydroxy justicidin C (3) have been isolated from the whole plant of Justicia procumbens, together with four known ones, neojusticin A (4), chinensinaphthol methyl ester (5), isodiphyllin (6) and taiwanin C (7). The complete assignments of 1H and 13C NMR chemical shifts for the new lignans and the 13C NMR chemical shifts for the known lignans were obtained for the first time by means of 2D NMR techniques, including HSQC and HMBC.     

Complete assignments of 1H and 13C NMR data for new dibenzocyclooctadiene lignans from Kadsura oblongifolia

Two new dibenzocyclooctadiene lignans, named kadoblongifolins A (1) and B (2), and one new natural product dibenzocyclooctadiene lignan, named kadoblongifolin C (3), were isolated from the stems of Kadsura oblongifolia (K. oblongifolia), together with five known ones, schizanrin F (4), propinquanin C (5), schisantherin G (6), heteroclitin Q (7), kadsurarin (8). The structures of these new lignans were elucidated by a combination of high‐resolution electron ionization mass spectrometry (HR‐EI‐MS), ¹H NMR, ¹³C NMR, HMQC, HMBC, and NOESY spectra. Copyright © 2009 John Wiley & Sons, Ltd.     

Complete assignments of 1H and 13C NMR data for three new arylnaphthalene lignan from Justicia procumbens

Three new arylnaphthalene lignans, named neojusticin C (1), procumbenoside C (2) and procumbenoside D (3), have been isolated from the whole plant of Justicia procumbens, together with three known ones, justicidinoside B (4), justicidinoside C (5), and diphyllin-1-O-beta-D-apiofuranoside (6). The complete assignments of 1H and 13C NMR data for three new lignans were first obtained by means of 2D NMR techniques, including HSQC and HMBC.     

Isolation of novel lignans, heteroclitins F and G, from the stems of Kadsura heteroclita, and anti-lipid peroxidative actions of heteroclitins A-G and related compounds in the in vitro rat liver homogenate system.

From the stems of Kadsura heteroclita, two new lignans named heteroclitins F and G were isolated and their structures were determined by various spectroscopic means including an X-ray diffraction method. Dibenzocyclooctadiene type lignans and related compounds isolated from the stems of K. heteroclita, potently inhibited the lipid peroxidation in the rat liver homogenate stimulated by Fe(2+)-ascorbic acid, CCl4-reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) and adenosine 5'-diphosphate-NADPH.     

Stereoselective synthesis of tetrahydrofuran lignans via BF(3) x OEt(2)-promoted reductive deoxygenation/epimerization of cyclic hemiketal: synthesis of (-)-odoratisol C, (-)-futokadsurin A, (-)-veraguensin, (+)-fragransin A(2), (+)-galbelgin, and (+)-talaumidin

A versatile route to the synthesis of 2,5-diaryl-3,4-dimethyltetrahydrofuran lignans, (-)-odoratisol C (1), (-)-futokadsurin A (2), (-)-veraguensin (3), (+)-fragransin A2 (4), (+)-galbelgin (5), and (+)-talaumidin (6), is described. Central to the synthesis of the lignans is BF(3) x OEt(2)-promoted deoxygenation/epimerization of the hemiketal 9a followed by stereoselective reduction of the oxocarbenium ion intermediates 8a,b.     

Lignans and Triterpenes from the Root of Pseuderanthemum carruthersii var. atropurpureum

Two new lignans, pseuderesinol (1), pseuderanoside (2) and a new triterpene, pseuderanic acid (3) were isolated from the dried root of Pseuderanthemum carruthersii (SEEM.) GUILL. var. atropurpureum (BULL.) FOSB. (Acanthaceae), together with ten known compounds, including five lignans, (+)-eudesmin (4), (+)-magnolin (5), (+)-syringaresinol (6), (+)-episyringaresinol (7), (+)-1-hydroxysyringaresinol (8) and five triterpenes, squalene (9), oleanolic acid (10), lupeol (11), betulin (12), betulinic acid (13). Their chemical structures were elucidated by 1D- and 2D-NMR, computational quantum chemistry, as well as high resolution-electrospray ionization (HR-ESI)-MS spectroscopic analysis. The acetylcholinesterase inhibition and cytotoxic activities against HeLa and MCF-7 cancer cell lines were evaluated on some purified compounds at the concentration of 100?μg/mL. Pseuderesinol (1) and magnolin (5) exhibited moderate cytotoxic activities against the MCF-7 cancer cell line.     

Two new diterpenoids from the buds of Wikstroemia chamaedaphne

Two new diterpenoids, wikstroelide Q (1) and prostratin Q (5), together with three known diterpenoids, pimelea factors P? (2), P? (3), and prostratin (4), and five known lignans, (+)-epipioresinol (6), (+)-isolariciresinol (7), (?)-lariciresinol (8), (+)-epi-sesaminone (9), and prestegane B (10), were isolated from the buds of Wikstroemia chamaedaphne Meissn. Their structures were elucidated by a combination of spectroscopic analyses. Compounds 1–10 were evaluated for their cytotoxicities against HL-60, SMMC-7721, A549, MCF-7, SW480, and BEAS-2B cell lines in vitro.     

Three new lignans, longipedunins A-C, from Kadsura longipedunculata and their inhibitory activity against HIV-1 protease

Three new lignans, longipedunins A (1), B (2) and C (3), together with three known compounds, benzoyl-binankadsurin A (4), acetyl-binankadsurin A (5) and schisanlactone A (6), were isolated from Kadsura longipedunculata. Their structures and stereochemistry were determined by spectral and single-crystal X-ray analyses. Compounds 1 and 6 showed appreciable inhibitory activity against HIV-1 protease with IC50 values of 50 and 20 microM, respectively.     

Chemical constituents from the leaves of Manglietia phuthoensis and their effects on osteoblastic MC3T3-E1 cells

Two new phenyl glycosides, mangliesides A and B (1, 2), a new ionol glycoside, manglieside C (3), two new lignan glycosides, mangliesides D and E (4, 5), were isolated from the leaves of Manglietia phuthoensis, along with two known lignans, 3-methoxymagnolol (6) and obovatol (7). Their structures were established by means of 1D and 2D NMR, electrospray ionization (ESI)-MS and HR-ESI-MS experiments. Among them, compounds 2 and 5 significantly (p<0.05) increased the growth and differentiation of osteoblastic MC3T3-E1 cells in vitro.     

Enzyme inhibiting lignans from Vitex negundo

Two new lignans trivially named negundins A (1) and B (2), were isolated along with (+)-diasyringaresinol (3), (+)-lyoniresinol (4), vitrofolal E (5) and vitrofolal F (6), reported for the first time from this species. The structures of the new compounds were established through spectral studies. Compound 2 showed potent inhibitory activity against lipoxygenase enzyme, while 5 showed moderate activity against butyryl-cholinesterase.     

Schoepfin A, B, C: three new chalcone C-glycosides from Schoepfia chinensis

Three new chalcone C-glycosides named schoepfin A, B, C (1-3), together with three known compounds 4,2',4'-trihydroxy-3'-C-beta-D-glucosylchalcone (4), nothofagin (5) and hemiphloin (6) were isolated from ethanolic extract of the bark of Schoepfia chinensis Gardn. et Champ (Olacaceae). Their structures were determined mainly by spectroscopic techniques including 2D-NMR (HMBC, HMQC) and MS experiments.     

Two pairs of enantiomeric neolignans from Lobelia chinensis

A pair of new enantiomeric neolignans, ethyl 3-[(2R,3S)-2-(4-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-7-methoxy-2,3-dihydro-1-benzofuran-5-yl] propanoate (+) (1) and ethyl 3-[(2S,3R)-2-(4-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-7-methoxy-2,3-dihydro-1-benzofuran-5-yl] propanoate (-) (1), together with a pair of known enantiomeric neolignans (+) (2) and (-) (2), as well as five known lignans (3-7) were isolated from the ethanol extract of Lobelia chinensis. Their structures were elucidated on the basis of extensive spectroscopic analyses, including 1D and 2D NMR, HR-ESI-MS and CD spectra.     

Sesquiterpenes and alkaloids from Lindera chunii and their inhibitory activities against HIV-1 integrase

Three new eudesmane type sesquiterpenoid lindenanolides E (1), F (2) and G (3), and two new aporphine alkaloid lindechunines A (18) and B (20) were isolated from roots of Lindera chunii MERR., together with seven known sesquiterpenes including a new naturally-occurring lindenanolide H (4) and eight known aporphine alkaloids. The structures of these compounds were determined by spectroscopic means. Of the isolated compounds, hernandonine (14), laurolistine (16), 7-oxohernangerine (17) and lindechunine A (18) showed significant anti-human immunodeficiency virus type 1 (HIV-1) integrase activity with IC(50) values of 16.3, 7.7, 18.2 and 21.1 microM, respectively. The major alkaloids presented in the roots of L. chunii were quantitatively analyzed by an HPLC method.     

Kunzeanones A, B, and C: novel alkylated phloroglucinol metabolites from Kunzea ambigua

Three new metabolites, kunzeanones A (1), B (2), and C (3), along with three known compounds, cryptostrobin (4), (+)-spathulenol (5), and (−)-globulol (6), were isolated from the non-polar fraction of the dried leaves of Kunzea ambigua (Myrtaceae), which shows ichthyotoxicity toward a small fish, medaka. The structures of these new compounds were elucidated as condensates of alkylated phloroglucinol with methylflavanone and germacrane-type sesquiterpene, respectively, on the basis of spectral analyses including 1-D and 2-D NMR spectra. The stereochemistries of kunzeanones A and B were determined by X-ray crystallographic analysis. A sesquiterpene, (+)-spathulenol (5), among the isolates was characterized as the ichthyotoxic principle of the extract.     

Docking of B-cell epitope antigen to specific hepatitis B antibody

The interaction of pres1 region of hepatitis B virus B-cell epitope antigen with specific hepatitis B neutralizing monoclonal antibody was examined by docking study. We modelled the 3D complex structure of B-cell epitope antigen residues CTTPAQGNSMFPSCCCTKPTDGNCY by homology modelling and docked it with the crystal structure of monoclonal antibody specific for the pres1 region of the hepatitis B virus. At the optimized docked conformation, the interactions between the amino acids of antigen and antibody were examined. It is found that the docked complex is stabilized by 59.3 kcal/mol. The stability of the docked antigen-antibody complex is due to hydrogen bonding and van der Waals interactions. The amino acids of the antigen and antibody responsible for the interaction were identified.     

Terpenoid-related metabolites from a formosan soft coral Nephthea chabrolii

Two new sesquiterpenoidal natural products chabrolidiones A and B (1 and 2), two C(18) terpenoid-related carboxylic acids, ketochabrolic acid (3) and isoketochabrolic acid (4), and one naphthoquinone derivative chabrolonaphthoquinone C (5), along with two known compounds (+)-aristolone (6) and teuhetenone A (7) were isolated from a Formosan soft coral Nephthea chabrolii. The structures of the new metabolites were determined on the basis of extensive spectroscopic analysis and by comparison of NMR data with those of related metabolites. Metabolite 1 has been synthesized previously, but was isolated for the first time from natural sources. Cytotoxic activity of metabolites 1-3 and 5-7 against a limited panel of cancer cell lines is also described.     

Rubriflorin A and B,Two Novel Partially Saturated Dibenzocyclooctene Lignans from Schisandra rubriflora

From the stems of Schisandra rubriflora, two novel partially saturated dibenzocyclooctene lignans, named rubriflorin A ( 1 ) and B ( 6 ), as well as the seven known partially saturated dibenzocyclooctene lignans kadsumarin A ( 2 ), kadsurin ( 3 ), heteroclitin B ( 4 ), heteroclitin C ( 5 ), heteroclitin D ( 7 ), interiorin ( 8 ), and interiorin B ( 9 ) were isolated. The structures of the new compounds 1 and 6 were established on the basis of spectral analysis as (5R,6S,7R,8R,13aS)‐8‐(acetyloxy)‐5,6,7,8‐tetrahydro‐1,2,3,13‐tetramethoxy‐6,7‐dimethylbenz([3,4]cycloocta[1,2‐f][1,3]benzodioxol‐5‐yl (2Z)‐2‐methylbut‐2‐enoate and (6R,7R,12aS)‐7,8‐dihydro‐12‐hydroxy‐1,2,3,10,11‐pentamethoxy‐6,7‐dimethyl‐6H‐dibenzo[a,c]cycloocten‐5‐one, respectively.     

Four new compounds, ficusal, ficusesquilignan A, B, and ficusolide diacetate from the heartwood of Ficus microcarpa

Three new lignans, ficusal (1) and ficusesquilignans A (2), B (3) and one new gamma-lactone, ficusolide diacetate (4), were isolated from the wood of Ficus microcarpa L.f. Their structures were determined by spectral evidence.