RESUMO
Eight previously undescribed sesquiterpene lactones (1-8), together with six known ones (9-14) were isolated from the aerial parts of Tithonia diversifolia (Hemsl.) A. Gray. The absolute configurations of these compounds were elucidated using HRMS, NMR spectroscopy, optical rotation measurements, X-ray crystallography, and ECD. Among them, sesquiterpene lactones 2-4 share a unique carbon skeleton with a rare C-3/C-4 ring-opened structure. Compounds 1 and 8 showed moderate inhibitory effects toward CT26 murine colon carcinoma cells by promoting lipid ROS production, highlighting their potential as ferroptosis inducers.
Assuntos
Antineoplásicos Fitogênicos , Asteraceae , Ferroptose , Lactonas , Sesquiterpenos , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Lactonas/química , Lactonas/farmacologia , Lactonas/isolamento & purificação , Ferroptose/efeitos dos fármacos , Animais , Camundongos , Asteraceae/química , Estrutura Molecular , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Relação Estrutura-Atividade , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Proliferação de Células/efeitos dos fármacos , Componentes Aéreos da Planta/química , Espécies Reativas de Oxigênio/metabolismoRESUMO
Five undescribed guanidine alkaloids, plumbagines HK (1-4) and plumbagoside E (5), as well as five known analogues (6-10) were isolated from the roots of Plumbago zeylanica. Their structures were established by extensive spectroscopic analyses and chemical methods. In addition, 1-10 were accessed their anti-inflammatory activities by measuring nitric oxide (NO) concentrations in LPS-induced RAW 264.7 cells. However, all compounds especially 1 and 3-5 could not inhibit the secretion of NO but significant increase the secretion of NO. The result reminded us that 1-10 may become potential novel immune potentiators.
Assuntos
Alcaloides , Plumbaginaceae , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Guanidinas/química , Guanidinas/isolamento & purificação , Guanidinas/farmacologia , Estrutura Molecular , Raízes de Plantas/química , Plumbaginaceae/química , Células RAW 264.7 , Animais , Camundongos , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Óxido Nítrico/metabolismo , Macrófagos/efeitos dos fármacos , Espectroscopia de Ressonância MagnéticaRESUMO
Five new glycosylated phenolic derivatives, rotundosides A-E (1-5), and three known glycosides (6-8) were isolated from the 95% alcohol extract of the bark of Ilex rotunda. Their structures were elucidated by extensive spectroscopic analysis and comparison with the literature data. All new compounds possessed a [5-O-(E)-caffeoyl]-ß-D-apiofuranosyl-(1â6)-ß-D-glucopyranosyl group. The anti-inflammatory properties of all isolated compounds were evaluated using a modified nitric oxide (NO) production in lipopolysaccharide (LPS)-induced leukemia cells in mouse macrophage (RAW264.7) method. Compound 8, dracunculifoside H, showed significant anti-inflammatory activity in vitro.
Assuntos
Ilex , Camundongos , Animais , Estrutura Molecular , Ilex/química , Casca de Planta/química , Glicosídeos/química , Anti-Inflamatórios/química , Fenóis/análiseRESUMO
Seven new hexasaccharide resin glycosides, named calysepins I-VII (1-7), with 27-membered rings, were obtained from the aerial parts of Calystegia sepium. Their structures with absolute configuration were established on the basis of spectroscopic data interpretation analysis and the use of chemical methods. They were defined as hexasaccharides composed of one d-quinovose, four d-glucose, and one l-rhamnose unit, and their sugar moieties were partially acylated by (2S)-methylbutanoic acid in 1-7 and (2R,3R)-nilic acid in 1-5 and 7, which mainly differed at the positions of acylation. Additionally, calysepin IV (4) exhibited cytotoxicity against A549 cells with an IC50 value of 5.2 µM.
Assuntos
Antineoplásicos , Calystegia , Convolvulus , Calystegia/química , Glicosídeos/química , Glicosídeos/farmacologia , Estrutura Molecular , Resinas Vegetais/químicaRESUMO
A phytochemical study performed on Inula japonica led to isolation of a new 1,10-seco-sesquiterpene dimer Neolinulicin A (1) and 1,10-seco-sesquiterpene Neolinulicin B (2), together with nine known sesquiterpenes (3-11). Among them, Neolinulicin A (1), which has a new carbon skeleton, was a Diels-Alder [4 + 2] adduct of two sesquiterpene moieties. Their structures were established by extensive spectroscopic analysis. All of the isolated compounds showed inhibition of NO production in RAW 264.7 macrophages. The findings might supply information for the future design of anti-inflammatory agents from I. japonica.
Assuntos
Anti-Inflamatórios/farmacologia , Inula/química , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , China , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química , Células RAW 264.7 , Sesquiterpenos/isolamento & purificaçãoRESUMO
Bioassay-guided fractionation of a cytotoxic extract derived from a solid potato dextrose agar (PDA) culture of Teratosphaeria sp. AK1128, a fungal endophyte of Equisetum arvense, afforded three new naphtho-γ-pyrone dimers, teratopyrones A-C (1-3), together with five known naphtho-γ-pyrones, aurasperone B (4), aurasperone C (5), aurasperone F (6), nigerasperone A (7), and fonsecin B (8), and two known diketopiperazines, asperazine (9) and isorugulosuvine (10). The structures of 1-3 were determined on the basis of their spectroscopic data. Cytotoxicity assay revealed that nigerasperone A (7) was moderately active against the cancer cell lines PC-3M (human metastatic prostate cancer), NCI-H460 (human non-small cell lung cancer), SF-268 (human CNS glioma), and MCF-7 (human breast cancer), with IC50s ranging from 2.37 to 4.12 µM while other metabolites exhibited no cytotoxic activity up to a concentration of 5.0 µM.
Assuntos
Antineoplásicos , Ascomicetos/química , Endófitos/química , Equisetum/microbiologia , Neoplasias/tratamento farmacológico , Pironas , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Ascomicetos/metabolismo , Endófitos/metabolismo , Feminino , Humanos , Células MCF-7 , Masculino , Neoplasias/metabolismo , Neoplasias/patologia , Células PC-3 , Pironas/química , Pironas/isolamento & purificação , Pironas/farmacologiaRESUMO
23,24-Dihydrocucurbitacin B (designated as C95 in this article) is a cucurbitane triterpenoid that has been shown to possess a variety of pharmacological activities, such as anti-inflammatory and anti-HIV-1 activities etc. In this study, we investigated the effects of 23,24-dihydrocucurbitacin B on lipid regulation. We showed that 23,24-dihydrocucurbitacin B (1-5 µM) dose-dependently promoted DiI-LDL uptake in HepG2 cells by upregulating low-density lipoprotein receptor (LDLR) protein. In HepG2 cells, 23,24-dihydrocucurbitacin B (1-10 µM) dose-dependently enhanced LDLR promoter activity by elevating the mature form of SREBP2 (sterol regulatory element binding protein 2) protein levels on one hand, and inhibited PCSK9 (proprotein convertase subtilisin/kexin type 9) promoter activity by attenuating HNF1α (hepatocyte nuclear factor-1α) protein levels in nuclei on the other hand. Consequently, the expression of LDLR protein markedly increased, whereas the PCSK9-mediated LDLR protein degradation decreased. In a high-cholesterol LVG golden Syrian Hamster model, administration of 23,24-dihydrocucurbitacin B (30 mg · kg-1â d-1, intragastric, for 3 weeks) significantly decreased the serum LDL-cholesterol (LDL-C) levels. PCSK9 protein levels in the serum and liver tissues were significantly decreased, whereas LDLR protein levels in liver tissues were significantly increased in the treated animals as compared with the control animals. In conclusion, our study demonstrates for the first time that 23,24-dihydrocucurbitacin B exhibits dual transcriptional regulation of LDLR and PCSK9 in HepG2 cells by increasing SREBP2 protein levels and decreasing HNF1α protein levels in the nuclei. These results propose a new strategy to simultaneously manage LDLR and PCSK9 protein expression and provide a promising lead compound for drug development.
Assuntos
Inibidores de PCSK9 , Receptores de LDL/metabolismo , Triterpenos/farmacologia , Administração Oral , Animais , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Conformação Molecular , Raízes de Plantas/química , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/genética , Relação Estrutura-Atividade , Trichosanthes/química , Triterpenos/administração & dosagem , Triterpenos/isolamento & purificação , Células Tumorais CultivadasRESUMO
BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) has been found to play a major role in atherosclerotic cardiovascular disease (ASCVD) by promoting hyperlipidemia. Its inhibition has therefore emerged as a viable drug target for improving the outcome of ASCVD. However, current monoclonal antibody PCSK9 inhibitors are considered cost ineffective and there is the need to discover new effective and cheaper small molecule alternatives. PURPOSE: The methanolic and ethanolic crude extracts of Nauclea latifolia have been shown to possess anti-hyperlipidemic activity, but the chemical component(s) responsible for this activity and the mechanism of action have remained unknown. The objective of this study was therefore to identify N. latifolia constituents with anti-hyperlipidemic activity and to investigate the inhibition of PCSK9 as a probable mechanism of action. METHOD: In the present study, compounds were isolated from the ethanolic extract of the stem of N. latifolia. The alkaloids were evaluated for their DiI-LDL uptake promoting activity in HepG2 cell. The most active compound was further assessed for its effect on low density lipoprotein receptor (LDLR) and PCSK9 protein expressions by western blot. RESULTS: 3R-3,14-dihydroangustoline (5), showed a relatively good activity in promoting LDL uptake (1.26-fold). It further increased LDLR protein expression and decreased the protein expression of PCSK9 in a dose dependent manner (1-50⯠µM). CONCLUSION: Alkaloids from N. latifolia may serve as a source of new PCSK9 inhibitors.
Assuntos
Aterosclerose/tratamento farmacológico , Células Hep G2/metabolismo , Alcaloides Indólicos/farmacologia , Extratos Vegetais/farmacologia , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/metabolismo , Rubiaceae/química , Aterosclerose/fisiopatologia , Humanos , Alcaloides Indólicos/química , Extratos Vegetais/uso terapêutico , Caules de Planta/químicaRESUMO
ABSTRACT About 31 percent of deaths worldwide result from atherosclerotic cardiovascular disease. Hyperlipidemia remains the major risk factor for this disease and therefore, it is necessary to identify antihyperlipidemic compounds for drug development. The crude ethanolic extract of Cryptolepis sanguinolenta (Lindl.) Schltr., Apocynaceae, has demonstrated antihyperlipidemic properties. However, the chemical constituents responsible for this action are unknown. Hence, to identify chemical constituent(s) of C. sanguinolenta with anti-hyperlipidemic effect, five indoloquinoline alkaloids were isolated and evaluated in 1,1′-dioctadecyl-3,3,3′,3′-tetramethyl-indocarbocyanine perchlorate labeled low density lipoprotein uptake assay using HepG2 cells. The minor alkaloid, isocryptolepine, showed strong activity in promoting low lipid lipoprotein uptake by 1.85-fold. Isocryptolepine may, therefore, serve as a lead compound for future studies in the development of novel antihyperlipidemic drugs.
RESUMO
The phytochemical study of Euphorbia helioscopia led to the isolation of 33 jatrophane diterpenoids (1-33), of which six (1-6) were new. This small jatrophane library was established to screen for potential lipid modulators. LDL-Uptake screening assay demonstrated that most of them improved LDL-Uptake rate in HepG2 cells, with compounds 16, 21 and 26 exhibiting more outstanding effects. Further exploration found that these three compounds could increase LDLR protein level in HepG2 cells dose-dependently. SAR studies suggested that substituted patterns of C-9, steric hindrance between C-14 and C-15, and the long conjugated fragment from C-5 to the carbonyl (C-9) were essential for the activity. Moreover, compound 21, a relatively abundant chemical in E. helioscopia, showed remarkable lipid-lowering effect in vivo, which makes it a promising lead for development of new lipid-lowering agents.
Assuntos
Diterpenos/isolamento & purificação , Euphorbia/química , Hipolipemiantes/isolamento & purificação , Lipoproteínas LDL/sangue , Animais , Diterpenos/farmacologia , Células Hep G2 , Humanos , Hipolipemiantes/farmacologia , Lipídeos/sangue , Lipoproteínas LDL/metabolismo , Mesocricetus , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Eleven withanolides including six previously undescribed compounds, 16ß-hydroxyixocarpanolide, 24,25-dihydroexodeconolide C, 16,17-dehydro-24-epi-dioscorolide A, 17-epi-philadelphicalactone A, 16-deoxyphiladelphicalactone C, and 4-deoxyixocarpalactone A were isolated from aeroponically grown Physalis philadelphica. Structures of these withanolides were elucidated by the analysis of their spectroscopic (HRMS, 1D and 2D NMR, ECD) data and comparison with published data for related withanolides. Cytotoxic activity of all isolated compounds was evaluated against a panel of five human tumor cell lines (LNCaP, ACHN, UO-31, M14 and SK-MEL-28), and normal (HFF) cells. Of these, 17-epi-philadelphicalactone A, withaphysacarpin, philadelphicalactone C, and ixocarpalactone A exhibited cytotoxicity against ACHN, UO-31, M14 and SK-MEL-28, but showed no toxicity to HFF cells.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Physalis/química , Extratos Vegetais/farmacologia , Vitanolídeos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade , Vitanolídeos/química , Vitanolídeos/isolamento & purificaçãoRESUMO
The phytochemical study of Euphorbia helioscopia afforded euphornin (1) in a large amount. Alkaline hydrolysis of 1 using potassium carbonate yielded the main product monodeacetyleuphornin (2), whose structural modification at 14-OH gave rise to 21 acylated derivatives euphornoate A-U (3-23). Thus, a mini compound library of jatrophanes was established to screen for MDR modulators. Biological studies clearly demonstrated the effect of C-14 pattern modification in MDR reversal activity and several compounds with RF values over 300 fold at 20⯵M (6, 16, 20, 22, 23) were thought to be promising MDR modulators. The SARs are discussed, which reveal that introduction of an alkyl acyl group bearing 4 carbons at C-14 or an aryl acyl group with electron donating groups is favorable for the activity.
Assuntos
Diterpenos/química , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Euphorbia/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Humanos , Células K562 , Componentes Aéreos da Planta/química , Relação Estrutura-AtividadeRESUMO
Vitex rotundifolia is the variant of the traditional Chinese medicine (TCM) Vitex trifolia. Diterpenoids from V. trifolia have shown anti-hyperlipidemia activity. As part of a continuous research program of searching for anti-hyperlipidemia constituents from TCM, 95% alcohol extract of the fruits of V. rotundifolia was fully studied, and 18 diterpenoids were isolated, including eight previously undescribed compounds (viterofolins A-H). Among them, viterofolins A-B were previously undescribed rearranged halimane-type diterpenoids, viterofolins CH were previously undescribed halimane-type diterpenoids. These compounds were then firstly evaluated in lipid (Dil-LDL) uptake assay in HepG2 cells. Viterofolin H, (5S, 6R, 8R, 9R, 10S)-6-acetoxy-9-hydroxy-13 (14)-labden-16,15-olide and previtexilactone showed moderate activities in promoting LDL uptake (1.27-1.35 fold). This work laid the foundation for searching anti-hyperlipidemia natural products.
Assuntos
Produtos Biológicos/farmacologia , Diterpenos/farmacologia , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/farmacologia , Lipoproteínas LDL/metabolismo , Vitex/química , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Diterpenos/química , Diterpenos/isolamento & purificação , Células Hep G2 , Humanos , Hiperlipidemias/metabolismo , Hipolipemiantes/química , Hipolipemiantes/isolamento & purificação , Medicina Tradicional Chinesa , Estrutura MolecularRESUMO
Chemical investigation of Euphorbia helioscopia resulted in the identification of seven new triterpenes named euphorbatrine A-G (1-7), including two (19αH)-lupane (1-2) and three (9ßH)-lanostane (4-6), which are very rare metabolites from plants. Their structures were elucidated by extensive spectroscopic analysis, X-ray crystallography and chemical methods. Compounds 5 and 6 triggered apoptosis of Hela-/- cell with EC50 values of 1.59±0.25 and 26.48±0.78µM, respectively.
Assuntos
Apoptose , Euphorbia/química , Triterpenos/isolamento & purificação , Células HeLa , Humanos , Estrutura Molecular , Componentes Aéreos da Planta/química , Triterpenos/farmacologiaRESUMO
Investigation of aeroponically grown Physalis peruviana resulted in the isolation of 11 new withanolides, including perulactones I-L (1-4), 17-deoxy-23ß-hydroxywithanolide E (5), 23ß-hydroxywithanolide E (6), 4-deoxyphyperunolide A (7), 7ß-hydroxywithanolide F (8), 7ß-hydroxy-17-epi-withanolide K (9), 24,25-dihydro-23ß,28-dihydroxywithanolide G (10), and 24,25-dihydrowithanolide E (11), together with 14 known withanolides (12-25). The structures of 1-11 were elucidated by the analysis of their spectroscopic data, and 12-25 were identified by comparison of their spectroscopic data with those reported. All withanolides were evaluated for their cytotoxic activity against a panel of tumor cell lines including LNCaP (androgen-sensitive human prostate adenocarcinoma), 22Rv1 (androgen-resistant human prostate adenocarcinoma), ACHN (human renal adenocarcinoma), M14 (human melanoma), SK-MEL-28 (human melanoma), and normal human foreskin fibroblast cells. Of these, the 17ß-hydroxywithanolides (17-BHWs) 6, 8, 9, 11-13, 15, and 19-22 showed selective cytotoxic activity against the two prostate cancer cell lines LNCaP and 22Rv1, whereas 13 and 20 exhibited selective toxicity for the ACHN renal carcinoma cell line. These cytotoxicity data provide additional structure-activity relationship information for the 17-BHWs.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Neoplasias Renais/tratamento farmacológico , Physalis/química , Neoplasias da Próstata/tratamento farmacológico , Vitanolídeos/isolamento & purificação , Vitanolídeos/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Melanoma/tratamento farmacológico , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Physalis/crescimento & desenvolvimento , Relação Estrutura-Atividade , Vitanolídeos/químicaRESUMO
Phytochemical investigation of the 70% acetone extract of the whole plant of Scutellaria barbata D. Don afforded six new neo-clerodane diterpenoids, scubatines A-F (1-6), and four known analogues (7-10). Their structures were elucidated on the basis of extensive spectroscopic analyses. Cytotoxic activity against the HL-60 and A549 cell lines was assessed for all isolated compounds. Compound 9 exhibited moderate activity against HL-60 with an IC50 value of 5.6µM. Compound 6 showed weak cytotoxic activity against A549 and HL-60 with IC50 values of 10.4 and 15.3µM, respectively.
Assuntos
Antineoplásicos Fitogênicos/química , Diterpenos Clerodânicos/química , Scutellaria/química , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Diterpenos Clerodânicos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Estrutura MolecularRESUMO
Phytochemical investigation of the 70% acetone extract of Croton crassifolius roots afforded eight new diterpenoids, crassins A-H (1-8), and 19 known compounds. The structures of the new compounds were determined by spectroscopic methods, and their absolute configurations were determined by electronic circular dichroism, single-crystal X-ray diffraction analysis, comparison with literature data, and biogenetic considerations. Crassins A (1) and B (2) are new ring B-rearranged diterpenoids, whereas crassin C (3) is a new ring A-rearranged diterpenoid. Crassin H (8) exhibited selective cytotoxicity against A549 cells (IC50 5.2 µM) compared with HL-60 cells (IC50 11.8 µM). The known compound chettaphanin-II exhibited moderate activity against the A549 and HL-60 cell lines (IC50 8.4 and 10.5 µM, respectively).
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Croton/química , Diterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Raízes de Plantas/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Cristalografia por Raios X , Diterpenos/química , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Células HL-60 , Humanos , Concentração Inibidora 50 , Conformação Molecular , Estrutura MolecularRESUMO
A new patchoulane-type sesquiterpenoid glycoside (1), together with five known sesquiterpenoids (2-6), was isolated from the roots of Croton crassifolius. Their structures were elucidated on the basis of spectroscopic methods. This is the first report about the sesquiterpenoid glycoside from C. crassifolius. All the isolated compounds 1-6 were evaluated for their cytotoxic activities against human tumour cell lines HL-60 and A549, but none showed significant activity.
Assuntos
Croton/química , Glicosídeos/isolamento & purificação , Raízes de Plantas/química , Sesquiterpenos/isolamento & purificação , Células A549 , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Glicosídeos/química , Glicosídeos/farmacologia , Células HL-60 , Humanos , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Análise EspectralRESUMO
Investigation of the hydrophobic extract of Rabdosia serra (Lamiaceae) led to the isolation of seven ent-6,7-secokaurane diterpenoids rabdosins E-K, along with twelve known ent-kaurane diterpenoids. Their structures were established by extensive spectroscopic analysis. The absolute configurations of rabdosins E, F, H and I were determined by single-crystal X-ray diffraction, with rabdosin E having a 3,20-epoxy group. These diterpenoids could be divided into two types according to their skeletons: rabdosins E-J are ent-6,20-epoxy-6,7-secokaur-1,7-olides, and rabdosin K is an ent-6,7-secokaur-7,20-olide. Cytotoxicity evaluation showed that serrin B, serrin A, isodocarpin and lushanrubescensin J exhibited weak to moderate cytotoxic activities (IC50<10µM) against two human cancer cell lines.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Isodon/química , Antineoplásicos Fitogênicos/química , Cristalografia por Raios X , Diterpenos do Tipo Caurano/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear BiomolecularRESUMO
Investigation of hydrophobic extract of Dichondra repens (Convolvulaceae) led to the isolation of three new resin glycosides dichondrins A-C (1-3), and three known resin glycosides cus-1, cus-2, and cuse 3. All the isolated resin glycosides with an acyclic core were evaluated for their multidrug resistance reversal activities, and the combined use of these compounds at a concentration of 25µM increased the cytotoxicity of vincristine by 1.03-1.78-fold.