<p> The C-B-A ring formation sequence has been adopted towards a total synthesis of podocarpic acid starting from 2, 7-dihydroxynaphthalene. Experimental procedures which were developed by other workers have been modified to improve the yields and the purity of the products. </p> <p> Using naturally occurring podocarpic acid, a reliable procedure has been explored for the functionalization of C-6 and C-7 positions in order to construct the 19,6-lactone ring in synthetically satisfactory yields. Catalytic reduction of the aromatic ring C, after functionalization of ring B, has been investigated with the aim of developing a pathway towards the elaboration of the C, D ring system of the kaurane skeleton. </p> / Thesis / Doctor of Philosophy (PhD)

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.

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-4&#945;-hydroxycleroda-13(16),14-diene and 3-oxo-4&#945;-hydroxy-13,14,15,16-tetranorclerodan-12-oic acid, and the flavonoid quercetin 3-O-&#946;-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(&#945;-pinen-10â-yl)-15-oxokauran-18-oic acid, two news clerodane diterpenes, 3-oxo-15,16-epoxy-4&#945;,12-dihydroxycleroda-13(16),14-diene and 15,16-epoxy-3&#945;,4&#945;,12-trihydroxycleroda-13(16),14-diene, one halimane-type diterpene, 15,16-epoxy-3&#945;,12-dihydroxyhalima-5(10),13(16),14-triene and the mixture of steroids &#946;-sitosterol and stigmasterol. From the ethanol extract of the roots, it was possible to isolate the flavonoids kaempferol 3-O-&#946;-glucopyranoside and ombuine 3-O-&#946;-rutinoside and the three new clerodane diterpenes 3&#945;,4&#945;,15,16-tetrahydroxyclerod-13-ene, 6-(&#946;-D-glucopyranosyl)-3,12-dioxo-15,16-epoxi-4&#945;-hydroxycleroda-13(16),14-dieno and 3-oxo-4&#945;,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-4&#945;-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(&#945;-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-4&#945;-hidroxicleroda-13(16),14-dieno e Ãcido 3-oxo-4&#945;-hidroxi-13,14,15,16-tetranorclerodan-12-oico, e do flavonoide 3-O-&#946;-D-glicopiranosilquercetina. A investigaÃÃo do extrato hexÃnico das raÃzes levou ao isolamento de um triterpeno, Ãcido acetilaleuritÃlico, do dÃmero inÃdito Ãcido ent-17(&#945;-pinen-10â-il)-15-oxocauran-18-oico, de dois novos diterpenos clerodanos, 3-oxo-15,16-epoxi-4&#945;,12-dihidroxicleroda-13(16),14-dieno e 15,16-epoxi-3&#945;,4&#945;,12-trihidroxicleroda-13(16),14-dieno, um diterpeno do tipo halimano, 15,16-epoxi-3&#945;,12-dihidroxihalima-5(10),13(16),14-trieno, e da mistura dos esteroides &#946;-sitosterol e estigmasterol. Do extrato etanÃlico das raÃzes foram isolados dois flavonoides, 3-O-&#946;-D-glicopiranosilcanferol e ombuina-3-O-&#946;-rutinosÃdeo, e trÃs diterpenos clerodanos inÃditos, 3&#945;,4&#945;,15,16-tetrahidroxicleroda-13-eno, 6-(&#946;-D-glicopiranosil)-3,12-dioxo-15,16-epoxi-4&#945;-hidroxicleroda-13(16),14-dieno e Ãcido 3-oxo-4&#945;,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-4&#945;-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(&#945;-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.