New Lignans from the Aerial Parts of Rudbeckia laciniata

Three new furofuran lignans, (+)‐4,4′‐O‐diangeloylpinoresinol ( 1 ), (+)‐4,4′‐O‐diangeloylmedioresinol ( 2 ), and (+)‐4,4′‐O‐diangeloylsyringaresinol ( 3 ), together with the known compound (+)‐syringaresinol, were isolated from the MeOH extract of Rudbeckia laciniata. The structure elucidation of these compounds were based on 1D‐ and 2D‐NMR, and HR‐ESI‐MS data. The additional structural evidence was obtained from alkaline hydrolysis of the compounds.     

Kadsutherins A–C: Three New Dibenzocyclooctane Lignans from the Stems of Kadsura Species

Three new dibenzocyclooctane‐type lignans, kadsutherins A–C ( 1 – 3 ), were isolated from the stems of two Kadsura species. Their structures and configurations were elucidated by spectroscopic methods including 2D‐NMR and HR‐MS techniques. Kadsutherin C ( 3 ) is the first dibenzocyclooctane lignan without an oxygen‐containing substituent at C(2).     

Two New Lignans from Phryma leptostachya L.

Haedoxancoside A ( 1 ), a new sesquilignan glycoside, and phrymarolin V ( 2 ), a new lignan, together with two known compounds, were isolated from Phryma leptostachya L. Their structures were determined on the basis of comprehensive spectroscopic analysis, mainly 1D‐ and 2D‐NMR spectroscopy as well as mass spectrometry. This is the first report of a sesquilignan glycoside isolated from a species of the Phrymaceae family.     

Three New Isoflavonoids from the Aerial Parts of Ammopiptanthus mongolicus

Three new isoflavonoids, namely (±)‐ammopiptanine A ( 1 ), ammopiptanine B ( 2 ), ammopiptanoside A ( 3 ), together with 13 known compounds, were isolated from the aerial parts of Ammopiptanthus mongolicus. Their structures were elucidated on the basis of detailed spectroscopic analyses and by comparison with those of related model compounds. The isoflavonoids described, except formononetin, wistin, daidzein, and calycosin, were isolated from this plant for the first time.     

Three New Compounds from the Aerial Parts of Caragana sinica

Two new stilbenoids, carasiphenol C ( 1 ) and Carasiphenol D ( 2 ), and one new dihydroaurone, carasinaurone ( 3 ), were isolated from the aerial parts of Caragana sinica, along with three known substances. Their structures were elucidated on the basis of spectroscopic methods and X‐ray‐diffraction analysis. Compound 2 showed significant biological activity against Pyricularia oryzae.     

Three New Chalcones from the Aerial Parts of Angelica keiskei

Three new chalcones, 3′‐carboxymethyl‐4,2′‐dihydroxy‐4′‐methoxychalcone ( 1 ), (±)‐4,2′,4′‐trihydroxy‐3′‐[(3‐hydroxy‐2,2‐dimethyl‐6‐methylenecyclohexyl)methyl]chalcone ( 2 ), and 2′′‐hydroxyangelichalcone ( 3 ), were isolated from the aerial parts of Angelica keiskei (Umbelliferae) together with five known compounds, artocarmitin A ( 4 ), (+)‐cis‐(3′R,4′R)‐methylkhellactone ( 5 ), (?)‐trans‐(3′R,4′S)‐methylkhellactone ( 6 ), 3,4‐dihydroxanthotoxin ( 7 ), and (Z)‐p‐coumaryl alcohol ( 8 ). The known compounds 4  –  8 were identified from A. keiskei for the first time. The structures of 1  –  3 were elucidated by interpreting spectroscopic data including 1D‐ and 2D‐NMR.     

Lignans from the Bark of Magnolia kobus

The Et₂O‐soluble fraction from the bark of Magnolia kobus led to the isolation of two new lignans, (+)‐(7α,7′α,8α,8′α)‐3′,4,4′,5,5′‐pentamethoxy‐7,9′: 7′,9‐diepoxylignan‐3‐ol ( 1 ) and (+)‐(7α,7′α,8α,8′α)‐4,5‐dimethoxy‐3′,4′‐(methylenedioxy)‐7,9′: 7′,9‐diepoxylignan‐3‐ol ( 2 ), along with five known lignans 3 – 7 . Their structures were established on the basis of various spectroscopic analyses including 1D‐ (¹H, ¹³C, and DEPT) and 2D‐NMR (COSY, NOESY, HMQC, and HMBC) and by comparison of their spectral data with those of related compounds.     

Four New Lignans with a Bicyclo[3.3.1]nonadienemethanol Skeleton from Cunninghamia lanceolata

Four unique bicyclo[3.3.1]nonadienemethanol lignans, designated lanceolatanins A ( 1 ), B ( 2 ), C ( 3 ), and D ( 4 ), along with one previously known compound, isolariciresinol ( 5 ), were isolated from the MeOH extracts of the heartwood of Cunninghamia lanceolata. Their structures were elucidated by application of various spectroscopic methods, including 1D‐ and 2D‐NMR techniques, to their acetylated derivatives 1a, 2a, 3a , and 4a . Their possible biosynthetic formations are also discussed.     

Lignans from the Bark of Zanthoxylum planispinum

A new dimeric lignan, named biplanispine A ( 1 ) which represents the first example of a dimeric 2,6‐diaryl‐3,7‐dioxabicyclo[3.3.0]octane skeleton from a Rutaceae plant, together with 13 known lignans 2 – 14 , was isolated from the bark of Zanthoxylum planispinum. Their structures were elucidated by spectroscopic methods, especially 2D‐NMR techniques. All isolated compounds were evaluated for their antibacterial activities by the disc diffusion method. Compounds 7 and 9 showed interesting antibacterial activities at 200 μg/disc; they were as effective as kanamycin sulfate at 10 μg/disc against Staphylococcus aureus and Bacillus subtilis.     

Structure and Cytotoxicity of Novel Lignans and Lignan Glycosides from the Aerial Parts of Larrea tridentata

Previously, the authors conducted phytochemical investigations of the aerial parts of Larrea tridentata and reported triterpene glycosides and lignan derivatives. In continuation of the preceding studies, 17 lignans and lignan glycosides (1–17) were isolated, including seven new compounds (1–7). Herein, the structure of the new compounds was determined based on spectroscopic analysis and enzymatic hydrolysis. The cytotoxicity of 1–17 against HL-60 human promyelocytic leukemia cells was examined. Compounds 4–11 and 14–16 were cytotoxic to HL-60 cells, with IC₅₀ values in the range of 2.7–17 μM. Compound 6, which was the most cytotoxic among the unprecedented compounds, was shown to induce apoptotic cell death in HL-60 cells.     

A New Cyclopeptide and Other Constituents from the Leaves of Zanthoxylum rigidum Humb. & Bonpl. ex Willd. (Rutaceae)

A new cyclopeptide, cyclozanthoxylane A ( 1 ), the lignans cis‐ and trans‐methylpluviatolide, the flavonoid isoquercitrin, along with a mixture of benzoic and cinnamic acid derivatives, were isolated from the MeOH extract of the leaves of Zanthoxylum rigidum (Rutaceae). The structures of the compounds were determined on the basis of 1D‐ and 2D‐NMR, and MS analysis. It is the first time that a natural cyclic peptide has been isolated from the genus Zanthoxylum.     

New Bisabolane-Type Sesquiterpenes from the Aerial Parts of Lippia dulcis

Two new bisabolane-type sesquiterpenes, lippidulcine A (3) and epilippidulcine A (4), have been isolated from the aerial parts of Lippia dulcis TREV. along with five known flavonoids, cirsimaritin (5), salvigenin (6), eupatorin (7), 5-hydroxy-6,7,3',4'-tetramethoxyflavone (8) and 5,3'-dihydroxy-6,7,4',5'-tetramethoxyflavone (9), three known phenylethanoid glycosides, decaffeoylverbascoside (10), acteoside (11) and isoacteoside (12), and two known iridoid glucosides, 8-epiloganin (13) and lamiide (14). Their chemical structures have been determined on the basis of spectroscopic data. Among them, 5, 7, and 9 exhibited almost the same activity as that of alpha-tocopherol, and 10-12 were identified as stronger antioxidants than alpha-tocopherol using the ferric thiocyanate method.     

Two New Cerebrosides from the Aerial Parts of Tithonia diversifolia

Two new cerebrosides, (2R)‐N‐{(1S,2S,3R,8E)‐1‐[(β‐D ‐glucopyranosyloxy)methyl]‐2,3‐dihydroxyheptadec‐8‐en‐1‐yl}‐2‐hydroxyhexadecanamide ( 1 ) and (2R)‐N‐{(1S,2R,8E)‐1‐[(β‐D ‐glucopyranosyloxy)methyl]‐2‐hydroxyheptadec‐8‐en‐1‐yl}‐2‐hydroxyhexadecanamide ( 2 ), were isolated from the aerial parts of Tithonia diversifolia (Hemsl .) A. Gray. Their structures were determined on the basis of spectroscopic analysis (IR, HR‐ESI‐MS, and 1D‐, and 2D‐NMR).     

New Cytotoxic Triterpenoids from the Aerial Parts of Euphorbia sieboldiana

Phytochemical investigation of the EtOH extract of Euphorbia sieboldiana led to the isolation of four new oleanane‐type triterpenoids, (1β,2α,3β,19β)‐1,2,3,19‐tetrahydroxyolean‐12‐en‐28‐oic acid, (1β,3β,19β)‐1,3,19‐trihydroxyolean‐12‐en‐28‐oic acid, (1β,2α,3β,16β,19β)‐1,2,3,16,19‐pentahydroxyolean‐12‐en‐28‐oic acid, and (1β,2α,3β,19β,23)‐1,2,3,19,23‐pentahydroxyolean‐12‐en‐28‐oic acid, along with 16 known compounds. Their structures were established by extensive 1D‐ and 2D‐NMR, as well as other spectral analyses. Biological evaluation of the four new triterpenoids revealed potent cytotoxic activities against HeLa and Hep‐G2 cells.     

New Lignans from the Roots of Taiwania cryptomerioides Hayata

The five new lignans designated 3′,4′‐de‐O‐methylenehinokinin ( 1 ), taiwaninolide ( 2 ), 8′‐hydroxysavinin ( 3 ), isoguamarol ( 4 ), and 4′‐O‐methylsalicifolin ( 5 ), as well as the new 4‐(3,4‐dimethoxybenzyl)dihydro‐3‐(4‐hydroxybenzyl)furan‐2(3H)‐one ( 6 ) were isolated from the roots of Taiwania cryptomerioides, besides the three known compounds hinokinin ( 8 ), savinin ( 9 ), and 3,4‐de‐O‐methylenehinokinin ( 7 ). The structures of the new constituents were elucidated through chemical and spectral studies. A compound previously isolated from the heartwood of Chamaecyparis obtusa var. formosana was assigned structure 1 ; however, this structure has now been revised to be 3,4‐de‐O‐methylenehinokinin ( 7 ).     

Three New Phenylpropanoids from Inula nervosa Wall.

Three new phenylpropanoid compounds, named nervolans A–C ( 1 – 3 , resp.), together with two other known phenylpropanoids, coniferyl diangelate and sinapyl diangelate, were isolated from the aerial parts of Inula nervosa Wall . (Asteraceae), a traditional Chinese medicinal plant. The structures of 1 – 3 were elucidated by detailed spectroscopic analyses, including HR‐ESI‐MS data and 2D‐NMR spectroscopy. Compounds 1 – 5 exhibited mild inhibitory effects against NO production in LPS‐stimulated RAW264.7 cells.     

Lignans and secoiridoid glycosides from the stem barks of Jasminum tortuosum

This paper reports on the first phytochemical analysis ever performed on Jasminum tortuosum Willd. This analysis, mainly carried out by means of column chromatography separation, NMR spectroscopy and mass spectrometry, led to the isolation and the identification of four compounds, namely the lignans ginkgool (1) and olivil-4′-O-β-glucopyranoside (2) and the secoiridoids oleoside dimethyl ester (3) and oleoside 11-methyl ester (4). The presence of these compounds is significant from a chemotaxonomic point of view, confirming the correct botanical classification of the species and, from a phytochemical standpoint, may suggest its possible use in the ethno-medicinal field.