Teucretol,a neo-clerodane diterpenoid from Teucrium creticum

From the aerial parts of Teucrium creticum a new neo-clerodane diterpenoid, teucretol, has been isolated, together with the previously known diterpenoids 6,19- diacetylteumassilin, 19-acetylgnaphalin and teucjaponin B. The structure of teucretol, 6,19-diacetoxy-4α,18;15,16-diepoxy-neo-cleroda-13(16),14-diene-12ξ,20-diol, was established by chemical and spectroscopic means.     

neo-Clerodane Diterpenoids from the Aerial Parts of Scutellaria barbata with Anti-Inflammatory Activity

The bioactivity-guided isolation on the Scutellaria barbata extract resulted in the purification of four undescribed neo-clerodane diterpenoids, scuttenlines A–D ( 1 – 4 ), alone with 20 known diterpenoids ( 5 – 24 ). The chemical structures of them were elaborated by extensive spectroscopic means, including 1D, 2D-NMR and HR-MS. The anti-inflammatory potential ability of 1 – 24 was screened in lipopolysaccharide-stimulated mouse RAW 264.7 cells. Scuttenline C (IC₅₀=1.9 μM) and 18 (IC₅₀=3.7 μM) exhibited potent activity to inhibit NO production.     

Neo-clerodane diterpenoids from Teucrium pyrenaicum and T. subspinosum

From the aerial parts of teucrium pyrenaicum two new neo-clerodane diterpenoids, teupyrins A and B, have been isolated. The structures of teupyrin A [3β,12S-diacetoxy-4α,18; 15,16-diepoxy-6-keto-neo-cleroda-13(16),14-diene-20R,19-hemiacetal] and teupyrin B [6α-acetoxy-4α,18; 15,16-diepoxy-3β,12ξ,19-trihydroxy-neo-cleroda-13(16),14-diene] were established mainly by spectroscopic means and, in the case of teupyrin A, by X-ray diffraction analysis. The acetone extract of the aerial parts of T. subspinosum yielded four previously known neo-clerodane diterpenoids: teucvin, teuflin, teucrin H2 and 6α-hydroxyteuscordin.     

New 4,5‐seco‐20(10→5)‐abeo‐Abietane Diterpenoids with Anti‐Inflammatory Activity from Isodon lophanthoides var. graciliflorus (Benth.) H.Hara

Three new 4,5‐seco‐20(10→5)‐abeo‐abietane diterpenoids, 16‐hydroxysalvilenone ( 1 ), 15‐hydroxysalprionin ( 2 ), and 11β,15‐dihydroxysalprionin‐12‐one ( 3 ), and nine known abietane diterpenoids, 4 – 12 , along with one known sempervirane diterpenoid, hispidanol A ( 13 ), were isolated from the aerial parts of Isodon lophanthoides var. graciliflorus. The structures of compounds 1 – 3 were determined on the basis of spectroscopic methods including extensive analysis of NMR and mass spectroscopic data. All diterpenoids were tested for their TNF‐α inhibitory effects on LPS‐induced RAW264.7 cells. Compound 9 (16‐acetoxyhorminone) was the most potent with an IC₅₀ value of 3.97±0.70 μm .     

Diterpenes from the Roots of Oryza sativa L. and Their Inhibition Activity on NO Production in LPS‐Stimulated RAW264.7 Macrophages

Two new pimarane diterpenoids, momilactone D ( 3 ) and momilactone E ( 5 ), along with three known diterpenoids, momilactone A ( 1 ), sandaracopimaradien‐3‐one ( 2 ), and oryzalexin A ( 4 ) were isolated from Oryza sativa roots. The chemical structures of the compounds were determined by spectroscopic data analysis. The isolated diterpenoids were evaluated for their ability to inhibit NO production and iNOS mRNA and protein expression in LPS‐stimulated RAW264.7 macrophages. Compound 4 showed strong inhibition activity on NO production, and compounds 1 and 4 decreased the expression of iNOS mRNA and protein levels.     

半枝莲抗肝癌活性部位的化学成分研究

前期研究发现,半枝莲(Scutellaria barbata)全草醇提物的乙酸乙酯萃取部位经大孔吸附树脂处理,其70%乙醇洗脱部位具有较好的抗肝癌活性。为明确其活性成分,该研究采用硅胶柱色谱、Sephadex LH-20柱色谱、制备TLC、半制备液相色谱等对活性部位进行分离和纯化,运用多种波谱分析方法鉴定了单体化合物结构,并利用CCK-8法评价了所有单体化合物对人肝癌HepG2细胞体外增殖抑制活性,同时利用分子对接技术考察了活性最好的化合物与肝癌靶标的结合情况。结果表明:(1)从该活性部位共分离得到14个化合物,包括12个新克罗烷型二萜类化合物和2个黄酮类化合物,分别鉴定为scutefolide C(1)、6-乙酰氧基-7-烟酸酰氧基半枝莲碱G(2)、scutestrigillosin D(3)、 scutehenanine D(4)、半枝莲碱A(5)、半枝莲碱B(6)、7-烟酸酰氧基半枝莲碱H(7)、半枝莲碱N(8)、半枝莲碱Y(9)、barbatin A(10)、barbatin B(11)、barbatin D(12)、5, 7, 6''-三羟基-2''-甲氧基黄酮醇(13)和5, 8-二羟基-6, 7-二甲氧基黄酮(14)。其中,化合物1-3、13、14为首次从该植物中分离得到。(2)活性测试结果显示,化合物4、7、10-12表现出较弱的HepG2细胞增殖抑制活性,化合物6的细胞增殖抑制活性和阳性对照(顺铂)活性接近,而化合物5表现出比顺铂更强的细胞增殖抑制活性。(3)分子对接结果显示,化合物5和化合物6与肝癌靶蛋白VEGF-2均具有良好的结合力。该研究结果不仅丰富了半枝莲的化学物质类群,也为进一步深入研究活性化合物抗肝癌的作用机制提供了参考。     

Rearranged abietane diterpenoid hydroquinones from aerial parts of Ajuga decumbens Thunb

Four new rearranged abietane diterpenoid hydroquinones, ajudecumins A–D (1–4), together with two known rearranged abietane diterpenoids, three neo-clerodane diterpenoids, four megastigmane derivatives, two flavonoids as well as a bisabolene sesquiterpenoid were isolated from the aerial parts of Ajuga decumbens. Their structures were established on the basis of extensive spectroscopic analysis and the stereochemistry of 1 was confirmed by single-crystal X-ray diffraction analysis. Among the diterpenoids, compounds 1 and 3 exhibited moderate inhibitory activity on the proliferation of human breast cancer MCF-7 cells.     

Antitumor Cembrane Diterpenoids from the South China Sea Soft Coral Lobophytum sp.

Two new highly functionalized cembrane diterpenoids named ximaolobophytolides A ( 1 ) and B ( 2 ) as minor components, together with seven related known compounds ( 3 – 9 ), have been isolated and identified from the Ximao soft coral Lobophytum sp. They were characterized by the presence of an α-methylene-γ-lactone moiety. Based on the comprehensive analyses of 1D and 2D NMR spectroscopic data, the absolute configurations of these two new compounds were elucidated by the combination of quantum mechanical (QM)-NMR and time-dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculation approaches. In the anti-tumor bioassays, compounds 3 – 9 showed moderate to significant inhibitory effects (IC₅₀ values ranging from 29.66 to 0.39 μM) against the proliferations of five tumor cells HEL, A549, H1975, MDA-MB-231, and H1299. It might be worthy to point out that compounds 4 , 7 , and 8 exhibited better anti-tumor activities than that of the positive control Doxorubicin.     

Diterpenoids and a Diarylheptanoid from Hedychium coronarium with Significant Anti‐Angiogenic and Cytotoxic Activities

Two new labdane diterpenoids, namely hedycoronals A and B ( 1 and 2 , resp.), were isolated from the rhizomes of Hedychium coronarium, together with eight known diterpenoids, 4 – 11 , and a known diarylheptanoid, 3 . The structures of 1 and 2 were established by detailed interpretation of their 1D‐ and 2D‐NMR spectra and HR‐ESI‐MS data. Inhibitory activities against human umbilical vein endothelial cells (HUMECs) proliferation and cytotoxic activities against four cancer cell lines were assessed for all the isolates. Most of these metabolites showed moderate or potent cytotoxic activities against four cancer cell lines. Moreover, compounds 3 and 8 exhibited promising inhibitory activities against HUMECs with the IC₅₀ values of 6.4 to 3.3 μM .     

Terpenoids from Rhizomes of Alpinia japonica Inhibiting Nitric Oxide Production

A new sesquiterpenoid, 1 , and three new diterpenoids, 3 – 5 , along with five known compounds, 2 and 6 – 9 , were isolated from rhizomes of Alpinia japonica. The structures of the new compounds were determined as (1R,4R,6S,7S,9S)‐4α‐hydroxy‐1,9‐peroxybisabola‐2,10‐diene ( 1 ), methyl (12E)‐16‐oxolabda‐8(17),12‐dien‐15‐oate ( 3 ), (12R)‐15‐ethoxy‐12‐hydroxylabda‐8(17),13(14)‐dien‐16,15‐olide ( 4 ), and methyl (11E)‐14,15,16‐trinorlabda‐8(17),11‐dien‐13‐oate ( 5 ) by means of spectroscopic data. The absolute configurations at C(4) in 1 and C(12) in 4 were deduced from the circular dichroism (CD) data of the in situ‐formed [Rh₂(CF₃COO)₄] complexes. Inhibitory effects of the isolates on NO production in lipopolysaccharide‐induced RAW264.7 macrophages were evaluated, and 2 – 4, 6 , and 7 were found to exhibit inhibitory activities with IC₅₀ values between 14.6 and 34.3 μM .     

Cuceolatins A–D: New Bioactive Diterpenoids from the Leaves of Cunninghamia lanceolata

Four new diterpenoids named cuceolatins A–D, including three labdane‐type ( 1 – 3 ) and one abietane‐type ( 4 ) as well as three known labdane analogs ( 5 – 7 ), were reported from the leaves of Cunninghamia lanceolata. Structural assignments for these compounds were conducted by analyses of spectroscopic data, and their absolute configurations were determined by time‐dependent density functional theory (TD‐DFT) based electronic circular dichroism (ECD) calculations. Among them, the abietane‐type diterpenoid (11‐hydroxy‐12‐methoxyabieta‐8,11,13‐trien‐3‐one ( 4 )) showed significant cytotoxicity against human MDA‐MB‐231, MCF‐7, and HeLa tumor cell lines with IC₅₀ measurements of 4.3, 2.8 and 4.5 μm , respectively, while the labdane‐type diterpenoids with a 4α‐carboxy group ( 1 – 3 and 5 ) exhibited moderate antibacterial activity towards Bacillus subtilis and Staphylococcus aureus with IC₅₀ values all below 25 μm .     

A New Harziane Diterpene,Harziaketal A,and a New Sterol,Trichosterol A,from the Marine-Alga-Epiphytic Trichoderma sp. Z43

One new diterpene, harziaketal A ( 1 ), and one new highly degraded sterol, trichosterol A ( 2 ), along with three known compounds, including one diterpene, harzianone ( 3 ), and two steroids, (22E,24R)-5α,6α-epoxy-ergosta-8(14),22-dien-3β,7α-diol ( 4 ) and isoergokonin B ( 5 ), were isolated from the culture of the marine-alga-epiphytic fungus Trichoderma sp. Z43 by silica gel column chromatography (CC), Sephadex LH-20 CC, and preparative thin-layer chromatography (TLC). Their structures and relative configurations were assigned by nuclear magnetic resonance (NMR) and high resolution electrospray ionisation mass spectrometry (HR-ESI-MS) data, and the absolute configuration of 1 was established by X-ray diffraction. Compound 1 features a hemiketal unit situated at the four-membered ring of harziane-type diterpenes for the first time, while 2 represents the rare occurrence of sterols with rings A and B being degraded. Compounds 1 and 2 displayed weak inhibition against the tested phytoplankton (Amphidinium carterae, Heterocapsa circularisquama, Heterosigma akashiwo, and Prorocentrum donghaiense) with half maximal inhibitory concentration (IC₅₀) ranging from 14 to 53 μg/mL.     

Diterpenoids from the stems of Tripterygium hypoglaucum (Celastraceae) and cytotoxic evaluation

Four new diterpenoids, 2α,16α-hydroxy-ent-kauran-19,20-olide (1), isopimara-8(14),15-diene-11β,19-diol (2), isopimara-8(14),15-diene-12α,19-diol (3), and 3-oxo-14,15-dihydroxyabieta-8,11,13-trien-19-ol (4), along with seven known compounds (5–11) were isolated from Tripterygium hypoglaucum. Their structures were established on the basis of extensive spectroscopic analysis. Triptolide (5) and 2-epitripdiolide (6) showed significant cytotoxicity against A549, DU145, KB, KBvin and MDA-MB-231 cell lines with IC₅₀ values of 0.0012–0.1306 μM in vitro.     

Cassane-Type Diterpenoids from the Seeds of Caesalpinia bonduc (L.) Roxb.

Ten new cassane-type diterpenoids were isolated from the seeds of Caesalpinia bonduc (L.) Roxb., including 6α-hydroxycaesalpinin P ( 1 ), 14-epi-caesalpinin E1 ( 2 ), 6-deacetylcaesalmin Z ( 3 ), 14-epi-caesalmin Z ( 4 ), caesalpinolides I ( 5 ), K ( 6 ), L ( 7 ), M ( 9 ) and N ( 10 ), and 14-epi-neocaesalpin L ( 8 ). Their planar structures and absolute configurations were fully determined by comprehensive spectroscopic methods, including 2D NMR and electronic circular dichroism spectra. Compounds 1 – 4 are tetracyclic cassane diterpenoids possessing a furan ring, and compounds 5 – 10 are tetracyclic cassane diterpenoids possessing a fused butenolide moiety. The anti-inflammatory and cytotoxic activities of the isolates were evaluated, while none of them showed obvious effects. The current study identified ten new cassane-type diterpenoids from the seeds of C. bonduc (L.) Roxb., which enriched the chemical diversity of the titled herbal medicine.     

neo-Clerodane diterpenes from Ajuga ciliata and their inhibitory activities on LPS-induced NO production

Two new neo-clerodane diterpenes, (12S)-6α-acetoxy-4α,18-epoxy-12-hydroxy-19-tigloyloxy-neo-clerod-13-en-15,16-olide (1) and 6α,18-diacetoxy-4α-hydroxy-19-tigloyloxy-neo-clerod-13-en-15,16-olide (2), along with three known analogs (3–5) have been isolated from the whole plants of Ajuga ciliata Bunge. Their structures were elucidated on the basis of spectroscopic data analyses (IR, ESI-MS, HR-ESI-MS, HMQC, HMBC, COSY, and NOESY). The inhibitory activities on LPS-induced NO production of these diterpenes were evaluated and compounds 1 and 5 showed inhibitory effects.     

Inheritance of gusA and neo genes in transgenic rice

Inheritance of foreign genes neo and gusA in rice (Oryza sativa L. cv. IR54 and Radon) has been investigated in three different primary (T₀) transformants and their progeny plants. T₀ plants were obtained by co-transforming protoplasts from two different rice suspension cultures with the neomycin phosphotransferase II gene [neo or aph (3) II] and the -glucuronidase gene (uidA or gusA) residing on separate chimeric plasmid constructs. The suspension cultures were derived from callus of immature embryos of indica variety IR54 and japonica variety Radon. One transgenic line of Radon (AR2) contained neo driven by the CaMV 35S promoter and gusA driven by the rice actin promoter. A second Radon line (R3) contained neo driven by the CaMV 35S promoter and gusA driven by a promoter of the rice tungro bacilliform virus. The third transgenic line, IR54-1, contained neo driven by the CaMV 35S promoter and gusA driven by the CaMV 35S.Inheritance of the transgenes in progeny of the transgenic rice was investigated by Southern blot analysis and enzyme assays. Southern blot analysis of genomic DNA showed that, regardless of copy numbers of the transgenes in the plant genome and the fact that the two transgenes resided on two different plasmids before transformation, the introduced gusA and neo genes were stably transmitted from one generation to another and co-inherited together in transgenic rice progeny plants derived from self-pollination. Analysis of GUS and NPT II activities in T₁ to T₂ plants provided evidence that inheritance of the gusA and neo genes was in a Mendelian fashion in one plant line (AR2), and in an irregular fashion in the two other plant lines (R3 and IR54-1). Homozygous progeny plants expressing the gusA and neo genes were obtained in the T₂ generation of AR2, but the homozygous state was not found in the other two lines of transgenic rice.     

Highly Oxygenated Labdane Diterpenoids from Stevia rebaudiana and Their Anti-Atherosclerosis Activities

Five unknown labdane diterpenoids Stevelins A–E ( 1–5 ), three known labdane diterpenoids ( 6–8 ) and three labdane norditerpenoids ( 9–11 ) were isolated from the Stevia rebaudiana. The structures were determined primarily via NMR spectroscopic data and HR-ESI-MS experiments. X-ray crystallography using CuK_α radiation was used to determine the absolute configurations of 1 , and the absolute configurations of 2–5 were deduced by electronic circular dichroism (ECD) calculations. The potential anti-atherosclerosis activities of all compounds were evaluated by measuring their inhibitory effects on the macrophage foam cell formation. As a result, most isolated compounds could significantly inhibit oxidized low-density lipoprotein (ox-LDL)-induced macrophage foam cell formation, which suggests that these compounds may be promising candidates in the treatment for atherosclerosis.     

Antimycobacterial Metabolites from Plectranthus: Royleanone Derivatives against Mycobacterium tuberculosis Strains

The antimycobacterial activities of eight diterpenes, 1 – 8 , isolated previously from Plectranthus and eleven esters, 9 – 19 , of 7α‐acetoxy‐6β,12‐dihydroxyabieta‐8,12‐diene‐11,14‐dione ( 5 ) were evaluated against the MTB strains H₃₇Rv and MDR. Only diterpenoids with a quinone framework revealed anti‐MTB activity. Abietane 5 and its 6,12‐dibenzoyl, 12‐methoxybenzoyl, 12‐chlorobenzoyl, and 12‐nitrobenzoyl esters, 9, 11, 12 , and 13 , respectively, showed potent activities against the MDR strain with MIC values between 3.12 and 0.39 μg/ml. Cytotoxic activities towards 3T3 and Vero cells were also evaluated. Compound 11 , with the best selectivity index, may be a suitable lead for further chemical modifications. The complete structural elucidation of the new esters, 9 – 14, 16, 18 , and 19 , as well as the NMR data of known derivatives 15 and 17 are reported.     

ent‐Kaurene Diterpenoids from Blepharispermum hirtum

The twigs and leaves of Blepharispermum hirtum Oliver (Asteraceae) were investigated for their larvicidal and antimicrobial activity. Fractionation of the extracts of the twigs, directed by brine shrimp test and antibacterial activities, led to the isolation of compounds 1 – 4 ; two of which are new ent‐kaurene diterpenoids, blepharispins A and B ( 1 and 2 , resp.). The structures of compounds 1 and 2 were established from spectral data. The absolute configuration at C(15) in 1 was inferred from Mosher ester analysis and relative configurations were suggested by a NOESY experiment. Compound 4 was significantly larvicidal to newly hatched naupleii of Artemia salina L. (BST LC₅₀=1.3 (3.7–0.0) μg/ml), but the blepharispins were not (BST LC₅₀>500 μg/ml). Nevertheless, compound 1 inhibited the growth of Staphylococcus aureus and Bacillus subtilis at a MIC value of 62.5 μg/ml. The significance of the bioactivity results and the presence of ent‐kaurene diterpenoids in B. hirtum are discussed from biosynthetic and local utilization viewpoints.