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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Synthesis of the kempane diterpene ring system, and regio- and stereoselectivity in the reductions of cyclic enediones /

Liu, Chunjian, January 1998 (has links)
Thesis (Ph.D.), Memorial University of Newfoundland, 1998. / Includes bibliographical references.
32

Synthetic studies of naturally occurring molecules with interesting biological activities /

Takenaka, Norito. January 2002 (has links)
Thesis (Ph. D.)--University of Chicago, Department of Chemistry, December 2002. / Includes bibliographical references. Also available on the Internet.
33

Efficacy and action of topical diterpenes from Euphorbia Peplus in non-melanoma skin cancer /

Jones, Brad. January 2002 (has links) (PDF)
Thesis (M.Phil.) - University of Queensland, 2003. / Includes bibliography.
34

Cardiovascular effects, molecular docking and chemo informatics analysis of compounds isolated from leonotis leonurus

Sasi, Abd-Alkarim Nour-Addin January 2015 (has links)
>Magister Scientiae - MSc / Leonotis leonurus (L. Leonurus) has relatively abundant diterpenes and has been used as a traditional herbal medicine for treating several ailments including influenza, muscular cramps, skin related diseases, menstrual, antilipidemic, hyperglycaemia and hypertension. In this study, diterpenoid compounds such as; Dubiin, SaponifiedDubiin, Hispanol, Marrubiin and DC9 were isolated from L. Leonurus plant. The cardiovascular effects of these isolated compounds were investigated in order to determine the response of anaesthetised normotensive Wistar rats (in-vivo) to the compounds. Also, the druglikeness of the isolated diterpenoid compounds and their binding interaction with β1 adrenoceptor (PDB: 2Y04), angiotensin II receptor (Ang II) (PDB: 3R8A), Angiotensin converting enzyme (ACE) (PDB: 4XX3), and renin receptor (PDB: 2X8Z) by using molecular docking methods and Chemoinformatics analysis was performed (in-silico). Important molecular descriptors and molecular docking were used in our Chemoinformatics (in-silico) analysis to study the druglikeness and the binding affinity for of each molecule (Dubiin, SaponifiedDubiin, Hispanol, Marrubiin and DC9). The molecular descriptors and the binding energy were calculated by using the molecular operating environment software (MOE 2013). The lowest energy and highest cluster conformations of the molecules were further analysed. All the five (5) diterpenoids were predicted to have good oral bioavailability after oral administration and passed the BloodBrain Barrier (BBB) rules. Also, the compounds were predicted to have high probability of being good Druglike candidates, except for DC9, which is predicted to have lower possibilities of being Druglike candidate than the other diterpenoids. Furthermore, these compounds (Dubiin, SaponifiedDubiin, Hispanol, Marrubiin and DC9) were shown to interact with β1 adrenoceptors in-silico, an interaction that was confirmed in-vivo by increases in Blood pressure (SP, DP and MAP) and Heart rate (HR). In anaesthetized normotensive male Wistar rats (in-vivo), Dubiin (0.5 40mg/kg; IV), SaponifiedDubiin (0.5 60mg/kg; IV) Hispanol (0.5 40mg/kg; IV), DC9 (0.5 40mg/kg; IV) and Marrubiin (0.5 40mg/kg; IV) produced dose dependent increase in Systolic pressure (SP), Diastolic pressure (DP), and Mean arterial pressure (MAP) at all doses. Also, the compounds produced dose dependent increase in Heart rate (HR). From the in-vivo and in-silico studies it can be concluded that all the five (5) isolated diterpenoid compounds showed cardiovascular effects on Blood pressure (BP) and Heart rate (HR) by acting as β1 adrenoceptor agonists. Also, these diterpenoids compounds could be responsible for the cardiovascular effect observed in the methanol extracts from previous studies. These cardioactive compounds are prototype or ''lead compounds'' for designing and developing new nontoxic and effective drugs for cardiovascular disease (CVD) treatment.
35

Isolation of Natural Products from Casearia nigrescens

Guza, Rebecca Clare 30 June 2004 (has links)
As part of the continuing work of the International Cooperative Biodiversity Group (ICBG), plant extracts were received from Madagascar. The extracts were screened for cytotoxicity using the A2780 human ovarian cancer cell line bioassay. The crude extract of Casearia nigrescens was fractionated and yielded five known compounds and one new compound that were cytotoxic. Mass spectrometry and 1D and 2D NMR techniques were used to determine the structure of the isolated compounds. The dichloromethane fraction of Casearia nigrescens was weakly active in the A2780 human ovarian cancer cell line bioassay. Further separation of the dichloromethane fraction resulted in the isolation of five known compounds (casearlucin A, caseamenbrol A, rel-18(S),19(R)-diacetoxy-18,19-epoxy-6(R)-hydroxy-2(S)-(2ξ-methylbutanoyloxy)-5(R),8(S),9(S),10(R)-cleroda-3,13(16),14-triene, casearlucin B, and rel-18(S),19(R)-diacetoxy-18,19-epoxy-2(S)-(2ξ-ethylbutanoyloxy)-5(R),8(S),9(S),10(R)-cleroda-3,13(16),14-triene) and one new compound (casearlucin L). Based on the available literature this was the first investigation of the natural products of Casearia nigrescens. The structure of the known compounds was determined by comparison of the NMR, MS, optical rotation, UV, and IR data with the data found in the literature. The structure of casearlucin L was determined by NMR data and comparison with the NMR data for similar known compounds. / Master of Science
36

In vitro and in vivo study of effects of andrographolide on hepatocarcinogenesis.

January 2006 (has links)
Lau Ven Gie Vengie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 113-121). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABSTRACT --- p.ii / 論文摘要 --- p.iv / TABLE OF CONTENTS --- p.vi / LIST OF FIGURES --- p.ix / LIST OF TABLES --- p.x / LIST OF ABBREVIATIONS --- p.xi / INTRODUCTION --- p.1 / Chapter I --- Hepatocellular Carcinoma --- p.1 / Risk factors --- p.1 / Stages in chemical carcinogenesis --- p.2 / Initiation --- p.2 / Promotion --- p.3 / Progression --- p.5 / Treatment of hepatocarcinoma --- p.6 / Chemotherapy ´ؤ hepatic arterial infusion (HAI) --- p.6 / Trans-arterial chemoembolization (TACE) --- p.7 / Radiofrequency ablation (RFA) --- p.8 / Percutaneous ethanol injection (PEI) --- p.9 / Liver resection --- p.9 / Liver transplantation --- p.10 / Chapter II --- Molecular Mechanisms: Oncogenes and Tumor-suppressor genes --- p.11 / Cell cycle control --- p.12 / p53 mutation in HCC --- p.13 / Normal functions of p53 and its target genes --- p.13 / p21(Wafl/Cipl/Sdil) --- p.13 / PCNA --- p.14 / Bcl-2 and Bax: the Bcl-2 family --- p.14 / Mdm2 --- p.17 / Chapter III --- Evaluation of the effects of hepatocarcinogenesis --- p.19 / GST-Pi --- p.19 / AST & ALT --- p.19 / Chapter IV --- Traditional Chinese Medicine (TCM) --- p.21 / Andrographis Paniculata --- p.21 / Pharmacological properties of andrographolide --- p.23 / Chapter V --- Aim of the project --- p.26 / MATERIALS AND METHODS --- p.27 / Chapter 1 --- Effects of andrographolide on cell viability and cell cycle --- p.27 / Chapter 1.1 --- Materials and solutions --- p.27 / Chapter 1.2 --- Preparation of solutions --- p.28 / Chapter 1.3 --- Procedures --- p.29 / Chapter 1.3.1 --- Seeding cells into culture flask --- p.29 / Chapter 1.3.2 --- Subculturing technique --- p.30 / Chapter 1.3.3 --- Neutral red assay --- p.30 / Chapter 1.3.4 --- DNA purification of HepG2 cells --- p.31 / Chapter 1.3.5 --- DNA gel electrophoresis --- p.32 / Chapter 1.3.6 --- Flow cytometry --- p.32 / Chapter 2 --- Effects of andrographolide on gene expressions --- p.33 / Chapter 2.1 --- Materials and solutions --- p.33 / Chapter 2.2 --- Preparation of solutions --- p.34 / Chapter 2.3 --- Procedures --- p.35 / Chapter 2.3.1 --- Cell treatments --- p.35 / Chapter 2.3.2 --- mRNA extraction from cell --- p.35 / Chapter 2.3.3 --- Determination of total RNA yield and quality yield --- p.36 / Chapter 2.3.4 --- RNA formaldehyde agarose gel electrophoresis --- p.36 / Chapter 2.3.5 --- cDNA synthesis --- p.37 / Chapter 2.3.6 --- "cRNA synthesis, labeling and amplification" --- p.39 / Chapter 2.3.7 --- cRNA purification --- p.40 / Chapter 2.3.8 --- Oligo GEArray hybridization --- p.41 / Chapter 2.3.9 --- Chemiluminescent detection --- p.43 / Chapter 2.3.10 --- Data analysis --- p.44 / Chapter 3 --- Effects of andrographolide on hepatocarcinogenesis in rats --- p.45 / Chapter 3.1 --- Materials and solutions --- p.45 / Chapter 3.2 --- Preparation of solutions --- p.46 / Chapter 3.3 --- Procedures --- p.47 / Chapter 3.3.1 --- Animal treatment --- p.47 / Chapter 3.3.2 --- Promotion (Experiment 1) --- p.48 / Chapter 3.3.3 --- Progression (Experiment 2) --- p.49 / Chapter 3.3.4 --- Extraction of blood serum --- p.52 / Chapter 3.3.5 --- Measurement of absorbance --- p.52 / Chapter 3.3.6 --- Tissue processing --- p.53 / Chapter 3.3.7 --- Hematoxylin and Eosin (H&E) Staining --- p.53 / Chapter 3.3.8 --- Immunohistochemical staining of GST-P --- p.54 / Chapter 3.3.9 --- Examination of liver sections --- p.55 / Chapter 4 --- "Effects of andrographolide on the expressions of Mdm2, p53, PCNA, Bax, Bcl-2 & p21" --- p.56 / Chapter 4.1 --- Materials and solutions --- p.56 / Chapter 4.2 --- Preparation of solutions --- p.57 / Chapter 4.3 --- Procedures --- p.59 / Chapter 4.3.1 --- Total mRNA extraction from liver --- p.59 / Chapter 4.3.2 --- Reverse transcription of mRNA to cDNA --- p.59 / Chapter 4.3.3 --- Protocol for polymerase chain reaction (PCR) --- p.60 / Chapter 4.3.4 --- DNA gel electrophoresis --- p.61 / Chapter 4.3.5 --- Nuclear protein extraction --- p.61 / Chapter 4.3.6 --- Cytosolic protein extraction --- p.62 / Chapter 4.3.7 --- Determination of protein concentration --- p.62 / Chapter 4.3.8 --- Immunoprecipitation of p53 from liver nuclear protein --- p.62 / Chapter 4.3.9 --- Protein gel electrophoresis by SDS-PAGE --- p.63 / Chapter 4.3.10 --- Western blotting --- p.64 / RESULTS --- p.66 / Chapter 1 --- Effects of andrographolide on cell viability and cell cycle --- p.66 / Chapter 2 --- Effects of andrographolide on gene expressions --- p.76 / Chapter 3 --- Effects of andrographolide on hepatocarcinogenesis in rats --- p.79 / Chapter 4 --- "Effects of andrographolide on the expressions of Mdm2, p53, PCNA, Bax, Bcl-2 & p21" --- p.91 / DISCUSSION --- p.102 / CONCLUSION --- p.111 / REFERENCES --- p.113
37

Estudo químico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae) / Chemical study of Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae)

Sousa, Antonio Honório de January 2014 (has links)
SOUSA, Antonio Honório de. Estudo químico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae). 2014. 279 f. Tese (Doutorado em química)- Universidade Federal do Ceará, Fortaleza-CE, 2014. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-10-04T15:43:43Z No. of bitstreams: 1 2014_tese_ahsousa.pdf: 13571451 bytes, checksum: dcde11370b56473403f20f179360abe9 (MD5) / Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2016-10-10T19:44:57Z (GMT) No. of bitstreams: 1 2014_tese_ahsousa.pdf: 13571451 bytes, checksum: dcde11370b56473403f20f179360abe9 (MD5) / Made available in DSpace on 2016-10-10T19:44:57Z (GMT). No. of bitstreams: 1 2014_tese_ahsousa.pdf: 13571451 bytes, checksum: dcde11370b56473403f20f179360abe9 (MD5) Previous issue date: 2014 / The present work reports the chemical study related to the stem and the roots of Croton limae, collected in Andaraí/BA. The phytochemical investigation of ethanol extract from the stem lead to the isolation of two kaurane-type diterpenes, ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid, two clerodane-type diterpenes, 3,12-dioxo-15,16-epoxy-4α-hydroxycleroda-13(16),14-diene and 3-oxo-4α-hydroxy-13,14,15,16-tetranorclerodan-12-oic acid, and the flavonoid quercetin 3-O-β-D-glucopyranoside. The investigation of the hexane extract from the roots lead to the isolation of one triterpene, acetyl aleuritolic acid, the new dimer ent-17(α-pinen-10’-yl)-15-oxokauran-18-oic acid, two news clerodane diterpenes, 3-oxo-15,16-epoxy-4α,12-dihydroxycleroda-13(16),14-diene and 15,16-epoxy-3α,4α,12-trihydroxycleroda-13(16),14-diene, one halimane-type diterpene, 15,16-epoxy-3α,12-dihydroxyhalima-5(10),13(16),14-triene and the mixture of steroids β-sitosterol and stigmasterol. From the ethanol extract of the roots, it was possible to isolate the flavonoids kaempferol 3-O-β-glucopyranoside and ombuine 3-O-β-rutinoside and the three new clerodane diterpenes 3α,4α,15,16-tetrahydroxyclerod-13-ene, 6-(β-D-glucopyranosyl)-3,12-dioxo-15,16-epoxi-4α-hydroxycleroda-13(16),14-dieno and 3-oxo-4α,12-dihydroxy-14,15,16-trinorclerodan-13-oic acid. Four aromatic derivatives amides from ent-kaur-16-en-18-oic acid were prepared through nucleophilic substitutive reactions. The corresponding methyl esters from the ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid were also obtained. Two new derivatives from 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno were prepared through reduction reaction and another one by the biotransformation of diterpene, made by the fungus Rhizopus stolonifer. Some isolated compounds and derivatives were submited to cytotoxic activity using ovarian (OVCAR-8), glioblastoma (SF-295) and colon (HCT-116) cell lines, and the compounds ent-kaur-16-en-15-oxo-18-oic acid and ent-17(α-pinen-10’-yl)-15-oxokauran-18-oic acid registered activity during preliminaries assays. The secondary metabolites were isolated through usual chromatography techniques, using thin layer chromatography, column chromatography, size exclusion chromatography and high performance liquid chromatography. The determination of the structure of the isolated compounds was performed through physical (melting point and optical rotation) and spectrometric techniques, such infrared (IR), high resolution mass spectrometry and nuclear magnetic resonance (NMR), including bidimensional experiments, and comparison with literature data. / O presente trabalho relata o estudo químico do caule e das raízes de Croton limae, coletado no município de Andaraí-BA. A investigação fitoquímica do extrato etanólico do caule levou ao isolamento de dois diterpenos do tipo caurano, ácido ent-caur-16-en-18-oico e ácido ent-caur-16-en-15-oxo-18-oico, dois diterpenos do tipo clerodano, 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e ácido 3-oxo-4α-hidroxi-13,14,15,16-tetranorclerodan-12-oico, e do flavonoide 3-O-β-D-glicopiranosilquercetina. A investigação do extrato hexânico das raízes levou ao isolamento de um triterpeno, ácido acetilaleuritólico, do dímero inédito ácido ent-17(α-pinen-10’-il)-15-oxocauran-18-oico, de dois novos diterpenos clerodanos, 3-oxo-15,16-epoxi-4α,12-dihidroxicleroda-13(16),14-dieno e 15,16-epoxi-3α,4α,12-trihidroxicleroda-13(16),14-dieno, um diterpeno do tipo halimano, 15,16-epoxi-3α,12-dihidroxihalima-5(10),13(16),14-trieno, e da mistura dos esteroides β-sitosterol e estigmasterol. Do extrato etanólico das raízes foram isolados dois flavonoides, 3-O-β-D-glicopiranosilcanferol e ombuina-3-O-β-rutinosídeo, e três diterpenos clerodanos inéditos, 3α,4α,15,16-tetrahidroxicleroda-13-eno, 6-(β-D-glicopiranosil)-3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e ácido 3-oxo-4α,12-dihidroxi-14,15,16-trinorclerodan-13-oico. Foram preparadas quatro amidas aromáticas derivadas do ácido ent-caur-16-en-18-oico e os respectivos ésteres metílicos dos ácidos ent-caur-16-en-18-oico e ent-caur-16-en-15-oxo-18-oico. Foram preparados dois derivados reacionais obtidos através de reações de redução do diterpeno clerodano 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e outro através da biotransformação deste diterpeno pelo fungo Rhizopus stolonifer. Alguns compostos isolados e derivados foram submetidos a testes de atividade citotóxica, utilizando linhagens de células tumorais de ovário (OVCAR-8), glioblastoma (SF-295) e colón (HCT-116), onde testes preliminares indicaram que os compostos ent-caur-16-en-15-oxo-18-oico e ácido ent-17(α-pinen-10’-il)-15-oxocauran-18-oico apresentaram atividade. Os metabólitos secundários foram isolados através de técnicas cromatográficas usuais, utilizando cromatografia em camada delgada, cromatografia em coluna, cromatografia por exclusão molecular e cromatografia líquida de alta eficiência. A determinação estrutural foi realizada através de métodos físicos (ponto de fusão e rotação óptica) e do uso de técnicas espectroscópicas e espectrométricas como infravermelho (IV), espectrometria de massas de alta resolução e ressonância magnética nuclear de hidrogênio (RMN 1H) e carbono-13 (RMN 13C), incluindo experimentos bidimensionais, além de comparação com dados da literatura.
38

Estudo quÃmico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae) / Chemical study of Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae)

Antonio HonÃrio de Sousa 22 August 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The present work reports the chemical study related to the stem and the roots of Croton limae, collected in AndaraÃ/BA. The phytochemical investigation of ethanol extract from the stem lead to the isolation of two kaurane-type diterpenes, ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid, two clerodane-type diterpenes, 3,12-dioxo-15,16-epoxy-4α-hydroxycleroda-13(16),14-diene and 3-oxo-4α-hydroxy-13,14,15,16-tetranorclerodan-12-oic acid, and the flavonoid quercetin 3-O-β-D-glucopyranoside. The investigation of the hexane extract from the roots lead to the isolation of one triterpene, acetyl aleuritolic acid, the new dimer ent-17(α-pinen-10â-yl)-15-oxokauran-18-oic acid, two news clerodane diterpenes, 3-oxo-15,16-epoxy-4α,12-dihydroxycleroda-13(16),14-diene and 15,16-epoxy-3α,4α,12-trihydroxycleroda-13(16),14-diene, one halimane-type diterpene, 15,16-epoxy-3α,12-dihydroxyhalima-5(10),13(16),14-triene and the mixture of steroids β-sitosterol and stigmasterol. From the ethanol extract of the roots, it was possible to isolate the flavonoids kaempferol 3-O-β-glucopyranoside and ombuine 3-O-β-rutinoside and the three new clerodane diterpenes 3α,4α,15,16-tetrahydroxyclerod-13-ene, 6-(β-D-glucopyranosyl)-3,12-dioxo-15,16-epoxi-4α-hydroxycleroda-13(16),14-dieno and 3-oxo-4α,12-dihydroxy-14,15,16-trinorclerodan-13-oic acid. Four aromatic derivatives amides from ent-kaur-16-en-18-oic acid were prepared through nucleophilic substitutive reactions. The corresponding methyl esters from the ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid were also obtained. Two new derivatives from 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno were prepared through reduction reaction and another one by the biotransformation of diterpene, made by the fungus Rhizopus stolonifer. Some isolated compounds and derivatives were submited to cytotoxic activity using ovarian (OVCAR-8), glioblastoma (SF-295) and colon (HCT-116) cell lines, and the compounds ent-kaur-16-en-15-oxo-18-oic acid and ent-17(α-pinen-10â-yl)-15-oxokauran-18-oic acid registered activity during preliminaries assays. The secondary metabolites were isolated through usual chromatography techniques, using thin layer chromatography, column chromatography, size exclusion chromatography and high performance liquid chromatography. The determination of the structure of the isolated compounds was performed through physical (melting point and optical rotation) and spectrometric techniques, such infrared (IR), high resolution mass spectrometry and nuclear magnetic resonance (NMR), including bidimensional experiments, and comparison with literature data. / O presente trabalho relata o estudo quÃmico do caule e das raÃzes de Croton limae, coletado no municÃpio de AndaraÃ-BA. A investigaÃÃo fitoquÃmica do extrato etanÃlico do caule levou ao isolamento de dois diterpenos do tipo caurano, Ãcido ent-caur-16-en-18-oico e Ãcido ent-caur-16-en-15-oxo-18-oico, dois diterpenos do tipo clerodano, 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e Ãcido 3-oxo-4α-hidroxi-13,14,15,16-tetranorclerodan-12-oico, e do flavonoide 3-O-β-D-glicopiranosilquercetina. A investigaÃÃo do extrato hexÃnico das raÃzes levou ao isolamento de um triterpeno, Ãcido acetilaleuritÃlico, do dÃmero inÃdito Ãcido ent-17(α-pinen-10â-il)-15-oxocauran-18-oico, de dois novos diterpenos clerodanos, 3-oxo-15,16-epoxi-4α,12-dihidroxicleroda-13(16),14-dieno e 15,16-epoxi-3α,4α,12-trihidroxicleroda-13(16),14-dieno, um diterpeno do tipo halimano, 15,16-epoxi-3α,12-dihidroxihalima-5(10),13(16),14-trieno, e da mistura dos esteroides β-sitosterol e estigmasterol. Do extrato etanÃlico das raÃzes foram isolados dois flavonoides, 3-O-β-D-glicopiranosilcanferol e ombuina-3-O-β-rutinosÃdeo, e trÃs diterpenos clerodanos inÃditos, 3α,4α,15,16-tetrahidroxicleroda-13-eno, 6-(β-D-glicopiranosil)-3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e Ãcido 3-oxo-4α,12-dihidroxi-14,15,16-trinorclerodan-13-oico. Foram preparadas quatro amidas aromÃticas derivadas do Ãcido ent-caur-16-en-18-oico e os respectivos Ãsteres metÃlicos dos Ãcidos ent-caur-16-en-18-oico e ent-caur-16-en-15-oxo-18-oico. Foram preparados dois derivados reacionais obtidos atravÃs de reaÃÃes de reduÃÃo do diterpeno clerodano 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e outro atravÃs da biotransformaÃÃo deste diterpeno pelo fungo Rhizopus stolonifer. Alguns compostos isolados e derivados foram submetidos a testes de atividade citotÃxica, utilizando linhagens de cÃlulas tumorais de ovÃrio (OVCAR-8), glioblastoma (SF-295) e colÃn (HCT-116), onde testes preliminares indicaram que os compostos ent-caur-16-en-15-oxo-18-oico e Ãcido ent-17(α-pinen-10â-il)-15-oxocauran-18-oico apresentaram atividade. Os metabÃlitos secundÃrios foram isolados atravÃs de tÃcnicas cromatogrÃficas usuais, utilizando cromatografia em camada delgada, cromatografia em coluna, cromatografia por exclusÃo molecular e cromatografia lÃquida de alta eficiÃncia. A determinaÃÃo estrutural foi realizada atravÃs de mÃtodos fÃsicos (ponto de fusÃo e rotaÃÃo Ãptica) e do uso de tÃcnicas espectroscÃpicas e espectromÃtricas como infravermelho (IV), espectrometria de massas de alta resoluÃÃo e ressonÃncia magnÃtica nuclear de hidrogÃnio (RMN 1H) e carbono-13 (RMN 13C), incluindo experimentos bidimensionais, alÃm de comparaÃÃo com dados da literatura.
39

An asymmetric carbene cyclization cycloaddition strategy toward the synthesis of indicol

Lam, Sze-kui., 林詩鉅. January 2005 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
40

The molecular mechanism of mitotic arrest induced by a novel diterpenoid pseudolaric acid B and a novel gene encoding RNA-bindingprotein 22

Wong, Kam-wai., 黃錦偉. January 2006 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy

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