Ingenane diterpenes from Euphorbia petiolata

From the whole plants of Euphorbia petiolata, four new ingenane-type diterpenoids, 3,20-O-diacetylingenol 5-O-(2' E,4' Z)-tetradecadienoate (1), 5,20-O-diacetylingenol 3- O-(2' E,4' Z)-tetradecadienoate (2), ingenol 3-O-(2' E,4' Z)-tetradecadienoate (3), and 5,20-O-isopropylidenylingenol 3-O-(2' E,4' Z)-tetradecadienoate (4) were isolated. Their structures were elucidated by spectroscopic methods and chemical transformations.     

阿昔洛韦联合羟基脲抗疱疹病毒的研究

目的 研究抗肿瘤药物羟基脲（HU）与抗病毒药物阿昔洛韦（ACV）联用抗疱疹病毒的协同增效作用。方法 体外实验应用VERO细胞培养法及MTT染色法进行实验,以Calcusyn软件计算、分析实验结果;体内实验采用单纯疱疹病毒Ⅰ型感染的兔角膜炎实验模型,用临床裂隙灯观察不同用药情况下兔角膜病变,进行Trouzdale评分,并分离病毒、滴定度及病理检查。结果 体外实验结果显示ACV：HU为1：312.5及1：100时,两药为协同作用;ACV：HU为1：50、1：25、1：10时,两药为拮抗作用。配比为1：300的阿昔洛韦和羟基脲联合治疗病毒性角膜炎,其疗效与0.1％的ACV相当。结论 羟基脲对阿昔洛韦抗HSV-Ⅰ活性在一定比例条件下,体内、外均有增效作用。     

Three new jatrophane-type diterpenes from Euphorbia pubescens

Three new macrocyclic jatrophane diterpene polyesters, named pubescenes A ( 1), B ( 2), and C ( 3), and the known compounds indole-3-aldehyde and scopoletin have been isolated and characterised from the whole dried plant of Euphorbia pubescens. The structures of the new compounds were established by spectroscopic means including 2D-NMR techniques such as COSY, HMQC, HMBC and NOESY experiments. Compounds 1 - 3 were evaluated for their in vitro effect on the growth of three human cancer cell lines MCF-7 (breast), NCI-H460 (lung) and SF-268 (CNS) as well as for their capacity to interfere with the proliferation of human peripheral blood lymphocytes. They exhibited a moderate growth inhibitory effect on the cancer cell line NCI-H460. No effect was observed on the mitogenic response of human lymphocytes to PHA.     

New diterpene polyesters isolated from Hungarian Euphorbia species

Sixteen new diterpene polyesters were isolated and identified from Hungarian Euphorbiaceae species. Two of them (21, 23) are based on formerly unknown diterpene core. The structures of three jatrophane type diterpene heptaester were elucidated (1, 3, 6), which are diterpenoids with the highest degree of esterification identified from this plant family. Some of the isolated compounds have pharmacological effects, others are under testing now.     

Four new myrsinol diterpenes from Euphorbia prolifera

Four new myrsinol diterpenes, euphorbialoids K–N (1–4), have been isolated from the roots of Euphorbia prolifera. Their structures were elucidated on the basis of extensive 1D and 2D NMR (COSY, HMQC, HMBC, and NOESY) and mass (ESI–MS and HR-ESI–MS) spectroscopic data analyses.     

Alicyclic diterpenes from solidago species

The aerial parts of SOLIDAGO DRUMMONDII afforded in addition to known compounds like germacrene D and beta-caryophyllene, eight alicyclic diterpenes all derived from geranylgeraniol. The main constituent was also isolated from S. RACEMOSA and S. FLEXICAULIS. The structures were elucidated by highfield (1)H-NMR spectroscopy.     

New cyclomyrsinol diterpenes from Euphorbia aellenii with their immunomodulatory effects

Chloroform–acetone extract of the aerial parts of Euphorbia aellenii Rech. f. (Euphorbiaceae) was investigated for its diterpenoidal constituents. This led to the isolation of two new and one known cyclomyrsinol-type diterpenes 1–3. The structures were elucidated on the basis of 1D and 2D ¹H and ¹³C NMR techniques, and in vitro immunomodulatory activity was evaluated by standard proliferation of human peripheral blood lymphocytes. Results showed that all the three compounds were found to inhibit lymphocyte proliferation significantly (p < 0.05) at 50 μg/ml concentration. Among them, compound 2 showed more activity against phytohemagglutinin-activated T-cell proliferation with an IC₅₀ of 40.4 ± 9.35 μg/ml.     

Anti-herpes simplex virus activity of alkaloids isolated from Stephania cepharantha

By screening water and MeOH extracts of 30 Chinese medicinal plants for their anti-herpes simplex virus (HSV)-1 activity, a MeOH extract of the root tubers of Stephania cepharantha HAYATA showed the most potent activity on the plaque reduction assay with an IC50 value of 18.0 microg/ml. Of 49 alkaloids isolated from the MeOH extract, 17 alkaloids were found to be active against HSV-1, including 13 bisbenzylisoquinoline, 1 protoberberine, 2 morphinane and 1 proaporphine alkaloids, while benzylisoquinoline and hasubanane alkaloids were inactive. Although N-methylcrotsparine was active against HSV-1, as well as HSV-1 thymidine kinase deficient (acyclovir resistant type, HSV-1 TK-) and HSV-2 (IC50 values of 8.3, 7.7 and 6.7 microg/ml, respectively), it was cytotoxic. FK-3000 was found to be the most active against HSV-1, HSV-1 TK- and HSV-2 (IC50 values of 7.8, 9.9 and 8.7 microg/ml) with in vitro therapeutic indices of 90, 71 and 81, respectively. FK-3000 was found to be a promising candidate as an anti-HSV agent against HSV-1, acyclovir (ACV) resistant-type HSV-1 and HSV-2.     

Euphopubescenol and euphopubescene, two new jatrophane polyesters, and lathyrane-type diterpenes from Euphorbia pubescens

The structures of euphopubescenol and euphopubescene, two new macrocyclic jatrophane diterpene polyesters, isolated from the whole dried plant of Euphorbia pubescens, were established as 5alpha,8alpha,15beta-triacetoxy-3alpha-benzoyloxy -4alpha-hydroxy -9,14-dioxo-13beta H-jatropha-6(17),11 E-diene ( 1) and 3beta,7beta,8beta,9alpha,14alpha,15beta-hexaacetoxy-2beta H-jatropha-5 E,11 E-diene ( 2) by 1D- and 2D-NMR (COSY, HMQC, HMBC and NOESY), IR, EI-MS and EI-FTICR-MS. Two known lathyrane derivatives, jolkinol A ( 3) and jolkinol A ( 4), whose (13)C-NMR spectra were assigned, were also isolated. Compounds 1 - 3 have been evaluated for their ability to inhibit the in vitro growth of three human tumour cell lines representing different tumour types, MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer) and SF-268 (CNS cancer). They inhibited both MCF-7 and NCI-H460 cell lines, with GI50 values ranging between 40.9 microM and 95.3 microM, but were found to be ineffective as growth inhibitors of the SF-268 cell line.     

Chemical constituents from Euphorbia wallichii and their biological activities

One rare diterpenoid which was an unusual phorbol derivative possessing a 5-ene-7-oxo functional group, wallichiioid A (1), and 17 known compounds (2–18) were isolated from the aerial parts of Euphorbia wallichii. The structures and relative configuration of these compounds were elucidated on the basis of extensive spectroscopic interpretation. All the known compounds were isolated from E. wallichii for the first time. Diterpenoids 1–5 were tested for their cytotoxicity against five cancer cell lines (A-549, MCF-7, Hep G2, HeLa, and P388) and showed IC₅₀ values in the range of 8.19–29.72 μg/mL. The antiangiogenic activities of diterpenoids 1–5 were also evaluated using a zebrafish model.     

Cytotoxicity and anti-hepatitis B virus activities of saikosaponins from Bupleurum species

Saikosaponins, the main active constituents of Bupleurum spp., have been shown to possess immunomodulatory, hepatoprotective, anti-tumor and anti-viral activities. In this study, saikosaponins a, c and d were evaluated for cytotoxicity and anti-hepatitis B virus ( HBV) activities. Results showed that, with the exception of saikosaponins a and d, HBV-transfected human hepatoma cells (2.2.15 cells) cultured with saikosaponin c showed a significantly lower level of HBeAg in culture medium. Saikosaponin c also possessed activity in inhibiting HBV DNA replication; this inhibitory effect was not due to the cytotoxicity of saikosaponin c or its effect on 2.2.15 cell proliferation. Although saikosaponin d exhibited cytotoxicity on 2.2.15 cells, it failed to inhibit HBV multiplication. The cytotoxicity of saikosaponin d against HepG2 human hepatocellular carcinoma cells was due to the induction of apoptosis through the activation of caspases 3 and 7, which subsequently resulted in poly-ADP-ribose-polymerase (PARP) cleavage. DNA fragmentation was clearly noted at more than 6 h after HepG2 cells exposure to saikosaponin d. The present study concludes that saikosaponin c exhibits anti-HBV activity and saikosaponin d possesses potent cytotoxicity against human hepatocellular carcinoma cells.     

抗疱疹病毒药物研究进展

对临床应用的抗疱疹病毒药物及其研究进展进行了综述，其中包括索利夫定、缬昔洛韦、喷昔洛韦、福米韦生、泛昔洛韦、西多福韦、n—docosanol及valganciclovir。     

Euphorbia thymifolia suppresses herpes simplex virus-2 infection by directly inactivating virus infectivity

1. The ethyl acetate (EtOAc) extract and 3-O-galloyl-4,6-(S)-hexahydroxydiphenoyl-d-glucose (3OG46HG) of Euphorbia thymifolia Linnea have been shown to exhibit anti-herpes simplex virus (HSV)-2 activity in vitro. In the present study, we investigated the mode of action of these two compounds in suppressing HSV-2 multiplication. 2. The results demonstrated that the EtOAc extract and 3OG46HG affected virus infectivity in a dose-dependent manner. The EtOAc extract significantly reduced virus infectivity at a concentration of 4.0 microg/mL, whereas 3OG46HG obviously diminished virus infectivity at concentration of a 0.5 microg/mL. The virucidal ability of the EtOAc extract was affected by the incubation period, but not by the incubation temperature. In the case of the action of 3OG46HG against HSV-2, the effects of incubation time and temperature were negligible. 3. In summary, the EtOAc extract and 3OG46HG of E. thymifolia are concluded to inhibit HSV-2 multiplication by reducing virus infectivity.     

New diterpenes from <Emphasis Type="Italic">Nigella damascena</Emphasis> seeds and their antiviral activities against herpes simplex virus type-1

Nigella species are rich source of dolabellane diterpenes. During our study of Nigella species, new dolabellane diterpenes, damasterpenes V–VIII were isolated. The structural determination of new compounds damasterpenes V–VIII is described with consideration of their absolute configurations. The antiviral activities against herpes simplex virus type-1 of the isolated compounds and their derivatives are also evaluated. Damasterpene V (inhibition 35.0%) and 2-phenylacetyl 13-benzoyl damasterpenol (32.0%) showed significant antiviral activity at 10 μM.     

New mirsinane-type diterpenes from Euphorbia microsciadia Boiss. with inhibitory effect on VEGF-induced angiogenesis

Euphorbia microsciadia (Euphorbiaceae) is a perennial plant growing in Iran. Two new cyclomyrsinol esters, 3-O-propionyl-5, 10, 14-O-triacetyl-8-O-(2′-methyl-butanoyl)-cyclomyrsinol (1) and 3, 5, 10, 14, 15-O-pentaacetyl-8-O-isobutanoyl-cyclomyrsinol (2) were isolated from the methanolic extract of its dried aerial parts. The structures were elucidated based on ¹³C- and ¹H-NMR as well as 2D-NMR, IR and different MS spectra. Anti-angiogenic activity was also evaluated on vascular endothelium growth factor (VEGF)-induced angiogenesis in cultured human umbilical vein endothelial cells in vitro by assessing capillary-like tube network formation.     

Four new diterpenoids isolated from the Euphorbia rapulum

Four new diterpenoids named 1-epi-9-hydroxydepressin (1), 1-epi-8-hydroxydepressin (2), 2,13,9-trihydroxy-labda-8(17),12(E),14-triene (3) and tagalsin I (4) were isolated from Euphorbia rapulum. The structures of these compounds were elucidated by means of various spectroscopic methods. All the isolated compounds were evaluated for cytotoxic activities against HepG2, MCF-7, and C6 cell lines, and compound 4 showed moderate selective activity against MCF-7 cell line with an IC₅₀ value of 31.8 μM.     

Virucidal activity of polysaccharide extracts from four algal species against herpes simplex virus

Herpes simplex virus types 1 and 2 (HSV-1, HSV-2) infections are common, but can cause serious infections in neonates and the immunocompromised. Drugs currently used to treat cutaneous or genital HSV infections are effective in limiting disease, but the emergence of drug resistant viruses in immunocompromised individuals can be problematic. While the prophylactic oral treatment with antiviral drugs can reduce virus shedding and transmission, there is a need for topical microbicides that have the potential to limit sexual transmission of the virus. Previous reports demonstrated the antiviral activity of complex sulfated polysaccharides extracted from various species of marine algae and suggested that they interfered with the attachment of virions to host cells. Here, we evaluated the antiviral activity of extracts from Undaria pinnatifida, Splachnidium rugosum, Gigartina atropurpurea, and Plocamium cartilagineum against HSV-1 and HSV-2. These extracts exhibited good activity when added during the first hour of viral infection, but were ineffective if added later. Plaque reduction assays, when the extracts were added prior to viral inoculation, yielded EC₅₀ values that ranged from 2.5–3.6 μg/ml for HSV-1 and 0.7–6.6 μg/ml for HSV-2. None of the extracts exhibited significant toxicity in a neutral red uptake assay (IC₅₀ >100 μg/ml). Subsequent assays showed that the compounds had potent virucidal activity and were active at very low concentrations. We conclude that these extracts are nontoxic and effective virucidal agents that warrant further investigation to examine their potential role in the prevention of HSV infections of humans.     

Mechanism and mode of action of 5-iodo-2-pyrimidinone 2'-deoxyribonucleoside, a potent anti-herpes simplex virus compound, in herpes simplex virus-infected cells.

The anti-herpes simplex virus type 2 (-HSV-2) action of 5-iodo-2-pyrimidinone deoxyribonucleoside (IPdR) was found to be exerted through inhibition of HSV DNA synthesis. The inhibition of viral DNA synthesis was not caused by inhibition of the synthesis of HSV-2-specified proteins or HSV-2 mRNA species involved with viral DNA synthesis or by depletion of deoxynucleotides. The inhibition of viral DNA synthesis may be due to damage to the DNA template in the nuclei or to an action at the DNA replication complex, because nuclei isolated from HSV-2-infected cells treated with IPdR could not support DNA synthesis in vitro. Moreover, the addition of exogenous template to the reaction enabled nuclear DNA synthesis to occur at the level of control. The major cellular metabolite of IPdR in HeLa S3 cells infected with HSV-2 was IPdR monophosphate, which was formed through virally specified kinase. Attempts to either identify or synthesize IPdR diphosphate and triphosphate were unsuccessful. The accumulation of IPdR monophosphate was dependent on the extracellular concentration of IPdR. IPdR monophosphate did not have any inhibitory effect on nuclear DNA synthesis, even at 200 microM. Thus, the action of IPdR could be due to an unidentified metabolite of IPdR or the depletion of a cellular metabolite that is essential for viral DNA synthesis.     

Two new cassane-type diterpenes from Calliandra californica with antituberculosis and cytotoxic activities

From the root of Calliandra californica two new cassane-type diterpenes were isolated and characterized, escobarine A (1) and B (2), which showed promising activities against two Mycobacterium tuberculosis strains. The microplate alamar blue assay was used to determine the minimum inhibitory concentrations (MIC) of 1 and 2 against M. tuberculosis H37Rv and the resistant CIBIN/UMF15 : 099 strains. The MIC of 1 against the resistant M. tuberculosis strain showed a value 8 times lower than that of rifampin. The structures of the bioactive constituents were established by extensive NMR data analyses (including 1D and 2D NMR). The relative configuration of 2 was confirmed by X-ray analysis and the absolute configurations of 1 and 2 were determined by the circular dichroism method. Additionally, 1 and 2 displayed remarkable cytotoxic activity when evaluated against five human tumor cell lines.     

New macrocyclic lathyrane diterpenes, from Euphorbia lagascae, as inhibitors of multidrug resistance of tumour cells

The new macrocyclic lathyrane diterpenes latilagascenes A and B ( 1 and 2), the diacetylated derivative of 2, latilagascene C ( 3), and the known diterpenes ent-16alpha,17-dihydroxyatisan-3-one ( 4) and ent-16alpha,17-dihydroxykauran-3-one ( 5), isolated from the methanol extract of Euphorbia lagascae, were examined for their effects on the reversal of multidrug resistance (MDR) on mouse lymphoma cells. Among the active lathyrane derivatives 1 - 3, compound 2 displayed the highest inhibition of rhodamine 123 efflux of human MDR1 gene transfected mouse lymphoma cells when compared to the untreated cells or the positive control verapamil. The new compounds are the first macrocyclic lathyrane diterpenes showing oxidation at C-16, whose structures were characterized by extensive spectroscopic methods, including 2D NMR experiments ( (1)H- (1)H COSY, HMQC, HMBC and NOESY). The known phenolic compounds vanillic acid ( 6), p-salicylic acid ( 7), isofraxidin ( 8) and cleomiscosin A ( 9) were also isolated from this species.