The Experts below are selected from a list of 145677 Experts worldwide ranked by ideXlab platform
Kuo Hsiung Lee - One of the best experts on this subject based on the ideXlab platform.
-
design synthesis and Cytotoxic Activity of novel sulfonylurea derivatives of podophyllotoxin
Bioorganic & Medicinal Chemistry, 2014Co-Authors: Zhijun Zhang, Jing Tian, Li Ting Wang, Mei Juan Wang, Xiang Nan, Liu Yang, Ying Qian Liu, Susan L Morrisnatschke, Kuo Hsiung LeeAbstract:Three series of novel sulfonylurea podophyllotoxin derivatives were designed, synthesized, and evaluated for in vitro Cytotoxicity against four tumor cell lines (A-549, DU-145, KB and KBvin). Compounds 14c (IC50: 1.41–1.76 μM) and 14e (IC50: 1.72–2.01 μM) showed superior Cytotoxic Activity compared with etoposide (IC50: 2.03– >20μM), a clinically available anticancer drug. Significantly, most of the compounds exhibited comparable Cytotoxicity against the drug-resistant tumor cell line KBvin, while etoposide lost Activity completely. Preliminary structure-Activity relationship (SAR) correlations indicated that the 4′-O-methyl functionality in podophyllotoxin analogues may be essential to maintain Cytotoxic Activity, while an arylsulfonylurea side chain at podophyllotoxin’s 4β position can significantly improve Cytotoxic Activity.
-
design synthesis and Cytotoxic Activity of novel spin labeled rotenone derivatives
Bioorganic & Medicinal Chemistry Letters, 2012Co-Authors: Kuo Hsiung Lee, Liu Yang, Ying Qian Liu, Emika OhkoshiAbstract:Abstract Three series of novel spin-labeled rotenone derivatives were synthesized and evaluated for Cytotoxicity against four tumor cell lines, A-549, DU-145, KB and KBvin. All of the derivatives showed promising in vitro Cytotoxic Activity against the tumor cell lines tested, with IC 50 values ranging from 0.075 to 0.738 μg/mL. Remarkably, all of the compounds were more potent than paclitaxel against KBvin in vitro, and compounds 3a and 3d displayed the highest Cytotoxicity against this cell line (IC 50 0.075 and 0.092 μg/mL, respectively). Based on the observed Cytotoxicity, structure–Activity relationships have been described.
-
isolation structures and structure Cytotoxic Activity relationships of withanolides and physalins from physalis angulata
Journal of Natural Products, 2007Co-Authors: Amooru G Damu, Ping Chung Kuo, Tsung Hsiao Kuo, Tzu Hsuan Chen, Kenneth F Bastow, Kuo Hsiung LeeAbstract:Phytochemical investigation of Physalis angulata was initiated following primary biological screening. Fractionation of CHCl3 and n-BuOH solubles of the MeOH extract from the whole plant was guided by in vitro Cytotoxic Activity assay using cultured HONE-1 and NUGC cells and led to the isolation of seven new withanolides, withangulatins B−H (1−7), and a new minor physalin, physalin W (8), along with 14 known compounds, including physaprun A, withaphysanolide, dihydrowithanolide E, physanolide A, withaphysalin A, and physalins B, D, F, G, I, J, T, U, and V. New compounds (1−8) were fully characterized by a combination of spectroscopic methods (1D and 2D NMR and MS) and the relative stereochemical assignments based on NOESY correlations and analysis of coupling constants. Biological evaluation of these compounds against a panel of human cancer cell lines showed broad Cytotoxic Activity. Withangulatin B (1) and physalins D (10) and F (11) displayed potent Cytotoxic Activity against a panel of human cancer ce...
-
isolation structures and structure Cytotoxic Activity relationships of withanolides and physalins from physalis angulata
Journal of Natural Products, 2007Co-Authors: Amooru G Damu, Ping Chung Kuo, Tsung Hsiao Kuo, Tzu Hsuan Chen, Kenneth F Bastow, Kuo Hsiung LeeAbstract:Phytochemical investigation of Physalis angulata was initiated following primary biological screening. Fractionation of CHCl3 and n-BuOH solubles of the MeOH extract from the whole plant was guided by in vitro Cytotoxic Activity assay using cultured HONE-1 and NUGC cells and led to the isolation of seven new withanolides, withangulatins B-H (1-7), and a new minor physalin, physalin W (8), along with 14 known compounds, including physaprun A, withaphysanolide, dihydrowithanolide E, physanolide A, withaphysalin A, and physalins B, D, F, G, I, J, T, U, and V. New compounds (1-8) were fully characterized by a combination of spectroscopic methods (1D and 2D NMR and MS) and the relative stereochemical assignments based on NOESY correlations and analysis of coupling constants. Biological evaluation of these compounds against a panel of human cancer cell lines showed broad Cytotoxic Activity. Withangulatin B (1) and physalins D (10) and F (11) displayed potent Cytotoxic Activity against a panel of human cancer cell lines with EC50 values ranging from 0.2 to 1.6 microg/mL. Structure-Activity relationship analysis indicated that withanolides and physalins with 4beta-hydroxy-2-en-1-one and 5beta,6beta-epoxy moieties are potential Cytotoxic agents.
Yoshihiro Mimaki - One of the best experts on this subject based on the ideXlab platform.
-
steroidal glycosides from agave utahensis and their Cytotoxic Activity
Journal of Natural Products, 2009Co-Authors: Akihito Yokosuka, Maki Jitsuno, Masatoshi Yamazaki, Yoshihiro MimakiAbstract:Eight new spirostanol saponins (1−8) and three new furostanol saponins (9−11) were isolated from the whole plants of Agave utahensis. The structures of 1−11 were determined by analysis of extensive spectroscopic data. The saponins were evaluated for their Cytotoxic Activity against HL-60 human promyelocytic leukemia cells. Compound 1 showed Cytotoxicity against HL-60 cells with an IC50 value of 4.9 μg/mL, induced apoptosis in HL-60 cells, and markedly activated caspase-3.
-
steroidal glycosides from agave utahensis and their Cytotoxic Activity
Journal of Natural Products, 2009Co-Authors: Akihito Yokosuka, Maki Jitsuno, Masatoshi Yamazaki, Satoru Yui, Yoshihiro MimakiAbstract:Eight new spirostanol saponins (1−8) and three new furostanol saponins (9−11) were isolated from the whole plants of Agave utahensis. The structures of 1−11 were determined by analysis of extensive spectroscopic data. The saponins were evaluated for their Cytotoxic Activity against HL-60 human promyelocytic leukemia cells. Compound 1 showed Cytotoxicity against HL-60 cells with an IC50 value of 4.9 μg/mL, induced apoptosis in HL-60 cells, and markedly activated caspase-3.
-
steroidal saponins from the whole plants of agave utahensis and their Cytotoxic Activity
Phytochemistry, 2009Co-Authors: Akihito Yokosuka, Yoshihiro MimakiAbstract:Abstract Phytochemical investigation of the whole plants of Agave utahensis Engelm. (Agavaceae) has resulted in the isolation of 15 steroidal saponins ( 1 – 15 ), including five spirostanol saponins ( 1 – 5 ) and three furostanol saponins ( 11 – 13 ). Structures of compounds 1 – 5 and 11 – 13 were determined by spectroscopic analysis and the results of hydrolytic cleavage. The isolated compounds were evaluated for their Cytotoxic Activity against HL-60 human promyelocytic leukemia cells.
-
steroidal glycosides from the underground parts of trillium erectum and their Cytotoxic Activity
Phytochemistry, 2008Co-Authors: Akihito Yokosuka, Yoshihiro MimakiAbstract:Six steroidal glycosides, along with 14 known compounds, were isolated from the underground parts of Trillium erectum L. (Liliaceae). The structures of 1-6 were determined on the basis of extensive spectroscopic analysis, including two-dimensional (2D) NMR data, and a few chemical transformations. The isolated compounds were evaluated for their Cytotoxic Activity against HL-60 human promyelocytic leukemia cells.
-
cholestane glycosides from the bulbs of ornithogalum thyrsoides and their Cytotoxic Activity against hl 60 leukemia cells
Journal of Natural Products, 2002Co-Authors: Minpei Kuroda, Yoshihiro Mimaki, Akihito Yokosuka, Fusako Hasegawa, Yutaka SashidaAbstract:Twelve bisdesmosidic cholestane glycosides (1-12), including nine new ones (1-9), were isolated from the bulbs of Ornithogalum thyrsoides by monitoring the Cytotoxic Activity on HL-60 leukemia cells. The structural assignment of the new compounds was carried out by spectroscopic analysis and the results of hydrolytic cleavage. The 3-O-monoglucosides with an aromatic acyl group at the C-16 diglycoside moiety (1, 12) were extremely Cytotoxic, with respective IC(50) values of 0.00016 and 0.00013 microg/mL, and the other compounds, except for 2, 5, and 8, also showed Cytotoxic Activity as potent as etoposide (IC(50) 0.30 microg/mL), used as a positive control. These cholestanes were concluded to contribute to the potent Cytotoxicity of the crude O. thyrsoides bulb extract.
Akihito Yokosuka - One of the best experts on this subject based on the ideXlab platform.
-
steroidal glycosides from agave utahensis and their Cytotoxic Activity
Journal of Natural Products, 2009Co-Authors: Akihito Yokosuka, Maki Jitsuno, Masatoshi Yamazaki, Yoshihiro MimakiAbstract:Eight new spirostanol saponins (1−8) and three new furostanol saponins (9−11) were isolated from the whole plants of Agave utahensis. The structures of 1−11 were determined by analysis of extensive spectroscopic data. The saponins were evaluated for their Cytotoxic Activity against HL-60 human promyelocytic leukemia cells. Compound 1 showed Cytotoxicity against HL-60 cells with an IC50 value of 4.9 μg/mL, induced apoptosis in HL-60 cells, and markedly activated caspase-3.
-
steroidal glycosides from agave utahensis and their Cytotoxic Activity
Journal of Natural Products, 2009Co-Authors: Akihito Yokosuka, Maki Jitsuno, Masatoshi Yamazaki, Satoru Yui, Yoshihiro MimakiAbstract:Eight new spirostanol saponins (1−8) and three new furostanol saponins (9−11) were isolated from the whole plants of Agave utahensis. The structures of 1−11 were determined by analysis of extensive spectroscopic data. The saponins were evaluated for their Cytotoxic Activity against HL-60 human promyelocytic leukemia cells. Compound 1 showed Cytotoxicity against HL-60 cells with an IC50 value of 4.9 μg/mL, induced apoptosis in HL-60 cells, and markedly activated caspase-3.
-
steroidal saponins from the whole plants of agave utahensis and their Cytotoxic Activity
Phytochemistry, 2009Co-Authors: Akihito Yokosuka, Yoshihiro MimakiAbstract:Abstract Phytochemical investigation of the whole plants of Agave utahensis Engelm. (Agavaceae) has resulted in the isolation of 15 steroidal saponins ( 1 – 15 ), including five spirostanol saponins ( 1 – 5 ) and three furostanol saponins ( 11 – 13 ). Structures of compounds 1 – 5 and 11 – 13 were determined by spectroscopic analysis and the results of hydrolytic cleavage. The isolated compounds were evaluated for their Cytotoxic Activity against HL-60 human promyelocytic leukemia cells.
-
steroidal glycosides from the underground parts of trillium erectum and their Cytotoxic Activity
Phytochemistry, 2008Co-Authors: Akihito Yokosuka, Yoshihiro MimakiAbstract:Six steroidal glycosides, along with 14 known compounds, were isolated from the underground parts of Trillium erectum L. (Liliaceae). The structures of 1-6 were determined on the basis of extensive spectroscopic analysis, including two-dimensional (2D) NMR data, and a few chemical transformations. The isolated compounds were evaluated for their Cytotoxic Activity against HL-60 human promyelocytic leukemia cells.
-
cholestane glycosides from the bulbs of ornithogalum thyrsoides and their Cytotoxic Activity against hl 60 leukemia cells
Journal of Natural Products, 2002Co-Authors: Minpei Kuroda, Yoshihiro Mimaki, Akihito Yokosuka, Fusako Hasegawa, Yutaka SashidaAbstract:Twelve bisdesmosidic cholestane glycosides (1-12), including nine new ones (1-9), were isolated from the bulbs of Ornithogalum thyrsoides by monitoring the Cytotoxic Activity on HL-60 leukemia cells. The structural assignment of the new compounds was carried out by spectroscopic analysis and the results of hydrolytic cleavage. The 3-O-monoglucosides with an aromatic acyl group at the C-16 diglycoside moiety (1, 12) were extremely Cytotoxic, with respective IC(50) values of 0.00016 and 0.00013 microg/mL, and the other compounds, except for 2, 5, and 8, also showed Cytotoxic Activity as potent as etoposide (IC(50) 0.30 microg/mL), used as a positive control. These cholestanes were concluded to contribute to the potent Cytotoxicity of the crude O. thyrsoides bulb extract.
Swapan Kumar Dolui - One of the best experts on this subject based on the ideXlab platform.
-
synthesis of zno nanoparticles and evaluation of antioxidant and Cytotoxic Activity
Colloids and Surfaces B: Biointerfaces, 2013Co-Authors: Dhaneswar Das, Bikash Chandra Nath, Pinkee Phukon, Amarjyoti Kalita, Swapan Kumar DoluiAbstract:ZnO nanoparticles were synthesized by thermal decomposition method and were characterized by UV-vis spectroscopy, XRD, SEM, EDX and TEM analysis. The resultant nanoparticles are nearly spherical and size is in the range of 40-50 nm. The antioxidant behavior of ZnO nanoparticles was assessed by scavenging free radicals of 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) with varying nanoparticle concentration and time interval individually. The DPPH scavenging Activity was monitored by UV-vis spectrophotometer. ZnO nanoparticles were also showing Cytotoxic Activity which was studied by hemolytic potentiality test.
Silvana Maria De Oliveira Santin - One of the best experts on this subject based on the ideXlab platform.
-
Cytotoxic Activity of guettarda pohliana mull arg rubiaceae
Natural Product Research, 2013Co-Authors: Paulo Roberto Neves De Oliveira, Glaucio Testa, Rebeca P Medina, Cecilia M A De Oliveira, Lucilia Kato, Cleuza C Da Silva, J Carvalho, Silvana Maria De Oliveira SantinAbstract:The Cytotoxic Activity of crude extracts and their fractions from leaves and roots of G. pohliana was assessed against nine human cancer cell lines: melanoma (UACC-62), breast (MCF-7), breast expressing the multidrug resistance phenotype (NCI-ADR), lung (NCI-460), prostate (PCO-3), kidney (786-0), ovarian (OVCAR), colon (HT-29) and leukaemia (K-562). The hexane fraction from leaves (HL) and ethyl acetate (EAR), chloroform (CR) and hydromethanolic (HMR) fractions from roots were the most active fractions against K-562 with GI50 values being lower than 1 μg mL− 1. Also, CR and HMR fractions were active against UACC-62 cell line in the same order of magnitude. The phytochemical study of the CR fraction allowed identifying the known iridoids secoxyloganin, sweroside and loganin.
