Design, Synthesis and Structure-Activity

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Design, Synthesis and Structure-Activity CARLA LOPES VARELA DESIGN, SYNTHESIS AND STRUCTURE-ACTIVITY RELATIONSHIPS STUDIES ON STEROIDAL AROMATASE AND 5α-REDUCTASE INHIBITORS AS ANTI-TUMORS Faculty of Pharmacy University of Coimbra 2013 CARLA LOPES VARELA DESIGN, SÍNTESE E ESTUDOS DE RELAÇÃO ESTRUTURA- ATIVIDADE DE ESTERÓIDES INIBIDORES DA AROMATASE E DA 5α-REDUCTASE COMO ANTI-TUMORAIS Faculdade de Farmácia Universidade de Coimbra 2013 Dissertação de candidatura ao Grau de Doutor em Farmácia, Especialidade em Química Farmacêutica, apresentada à Faculdade de Farmácia da Universidade de Coimbra Aos meus pais, Guiomar e Carlos À minha avó Trindade, in memoriam Trabalho realizado sob a orientação do(a) Professor(a) Doutor Elisiário José Tavares da Silva, Faculdade de Farmácia da Universidade de Coimbra Doutora Fernanda Maria Fernandes Roleira, Faculdade de Farmácia da Universidade de Coimbra Doutora Natércia Aurora Almeida Teixeira, Faculdade de Farmácia da Universidade do Porto O presente trabalho foi realizado no Grupo de Química Farmacêutica da Faculdade de Farmácia da Universidade de Coimbra sobre a supervisão do Professor Doutor Elisiário Tavares da Silva e da Professora Doutora Fernanda Roleira, em colaboração com o Departamento de Ciências Biológicas – Laboratório de Bioquímica da Faculdade de Farmácia da Universidade do Porto e com o Grupo de Biologia da Inflamação e Repodução do Instituto de Biologia Molecular e Celular (IBMC) sob a supervisão da Professora Doutora Natércia Teixeira. Uma parte foi realizada no Departmento de Química Orgânica da Faculdade de Farmácia da Universidade de Santiago de Compostela, Espanha. Este trabalho teve o apoio financeiro da Fundação para a Ciência e Tecnologia (FCT) através da atribuição de uma bolsa de doutoramento (SFRH/BD/44872/2008) co-financiada pelo Fundo Social Europeu (FSE) e através da atribuição de um projeto FCOMP-01-0124-FEDER-020970 (PTDC/QUI- BIQ/120319/2010) financiado pelo Fundo Europeu de Desenvolvimento Regional (FEDER) através do Programa Operacional Factores de Competitividade (COMPETE) e por fundos nacionais através da FCT. AGRADECIMENTOS Aos meus orientadores, Prof. Doutora Fernanda Roleira e Prof. Doutor Elisiário Tavares da Silva, quero agradecer desde logo o facto de me terem aceite para integrar a sua investigação. Agradeço-lhes o voto de confiança, toda a ajuda, a paciência e a partilha das dificuldades e dos sucessos, quando os anteriores eram ultrapassados. Obrigada por terem estado sempre presentes, por me terem feito sentir como elemento apreciado nesta equipa e por me terem ajudado a crescer científica e pessoalmente, ao longo destes 4 anos. Considero-me uma privilegiada por ter tido a oportunidade de realizar este projeto de vida com eles! São de facto pessoas únicas e muito especiais! Muito Obrigada! À Prof. Doutora Natércia Teixeira, minha co-orientadora, agradeço a sua colaboração neste trabalho bem como a oportunidade de poder alargar os meus conhecimentos na área da bioquímica. Sem o seu contributo, cooperação e colaboração, este trabalho não teria sido possível. Ainda, um agradecimento por me ter aceite como sua aluna de doutoramento. Ao Prof. Doutor Saul da Costa, um agradecimento especial pela sua ajuda, disponibilidade, partilha de ideias e incentivo. Ao Prof. Doutor Rui Carvalho, um agradecimento especial por todo o seu apoio na Ressonância. Obrigada pela disponibilidade e paciência que teve comigo em cada sessão de RMN. À Prof. Doutora Georgina Correia da Silva e à recente Doutora Cristina Amaral, agradeço por todo o apoio do ponto de vista bioquímico e biológico. Sem o vosso contributo, cooperação e colaboração, este trabalho não teria sido possível. À Prof. Doutora Lourdes Santana e ao Prof. Doutor Eugénio Uriarte, um agradecimento especial pela forma tão hospitaleira com que me acolheram no seu laboratório em Santiago de Compostela. À Prof. Doutora Teresa Baptista e à Doutora Teresa Amaral, obrigada pelo apoio no HPLC, e pela boa disposição nas sessões madrugada adentro na tentativa de separar aqueles dois isómeros. Obrigada à Melinha, pela alegria de sempre! Obrigada também às nanomeninas e restantes colegas dos laboratórios de Tecnologia Farmacêutica e Farmacologia pelos divertidos “seminários”! À Susana e à Maria João que permitiram que o tempo que estive em Santiago de Compostela tivesse passado a voar e sempre com boa disposição! Ainda em Santiago, obrigada à Saleta e às meninas do laboratório de Tecnologia Farmacêutica pelos momentos bem passados! À Graça, um agradecimento especial pelo carinho e ânimo diários. À Célia e à Tânia, obrigada pela vossa estima! Aos alunos que ao longo destes anos passaram pelo laboratório, um agradecimento pela jovialidade que trouxeram à “minha casota”, sobretudo à Ana e à Xana pelos momentos em Berlim! Às minhas amigas, Catarina, Fátima Vilela e Fátima Pina, obrigada pela paciência com que me ouviram estes anos falar das minhas reações, das colunas, dos isómeros que não se queriam separar! Obrigada por todo o vosso apoio e amizade! Ao GANG, muito obrigada pela vossa amizade... Um especial agradecimento à minha amiga Xé, pelo apoio e pela pessoa especial que é! À minha Tia Alzira e Tia Fernanda, um agradecimento especial pelo imenso carinho, força, ânimo e por terem sempre acreditado em mim! Obrigada Tias, pelo vosso apoio e cuidado que todos os dias têm comigo! À minha mana Delmar, obrigada por estares sempre presente.... Por me teres ajudado a crescer e pelos mimos, mesmo que à distância! Ao meu mano Tanito, pela alegria e boa disposição! Ao Francisco obrigada pela paciência, compreensão e apoio que me deu ao longo destes anos. Aos meus pais, Guiomar e Carlos, o maior dos agradecimentos. Obrigada pelo vosso apoio constante, por serem os maiores entusiastas deste meu percurso académico e por serem os primeiros a acreditar que sou capaz! Sem vocês, nada disto teria sido possível! Muito obrigada pelo vosso amor!!! TABLE OF CONTENTS Publications xxiii Abstract xxxiii Resumo xxxix List of Abbreviations xlv Index of Figures xlix Index of Schemes liii Outline of the Thesis lv CHAPTER I - STEROIDAL AROMATASE INHIBITORS AS ANTI-TUMORS 1 INTRODUCTION 5 A.1. Breast Cancer: Some Facts 5 A.2. Estrogens 8 A.2.1. Estrogen Receptors 8 A.2.2. Estrogen Biosynthesis 10 A.3. Aromatase 10 A.4. Breast Cancer Treatment 16 A.4.1. Surgery 16 A.4.2. Chemotherapy 16 A.4.3. Radiation Therapy 17 A.4.4. Targeted Therapy 17 A.4.5. Hormonal Therapy 17 A.4.5.1. Estrogen Receptor Antagonists 18 A.4.5.2. Aromatase Inhibitors (AIs) 20 AIM OF THE WORK 32 1.1. DERIVATIVES OF EXEMESTANE 33 1.1.1. Design and synthesis 33 1.1.2. Chemistry 37 1.1.3. Biochemistry and biology 41 1.1.4. Structure-activity relationships discussion and conclusions 42 1.2. DERIVATIVES OF FORMESTANE 44 1.2.1. Design and synthesis 44 1.2.2. Chemistry 46 1.2.3. Biochemistry 47 1.2.4. Structure-activity relationships discussion and conclusions 47 1.3. A- AND D-RING MODIFIED DERIVATIVES OF ANDROSTENEDIONE 50 1.3.1. C-3 Hydroxyl Derivatives of Androstenedione and Testosterone 50 1.3.1.1. Design and synthesis 50 1.3.1.2. Chemistry 52 1.3.1.3. Biochemistry and biology 52 1.3.1.4. Structure-activity relationships discussion and conclusions 54 1.3.2. A-Ring Olefins and Epoxides Derivatives of Androstenedione 57 1.3.2.1. Design and synthesis 57 1.3.2.2. Chemistry 59 1.3.2.3. Biochemistry and biology 67 1.3.2.4. Structure-activity relationships discussion and conclusions 68 1.3.3. Derivatives of 5α-Androst-3-en-17-one 73 1.3.3.1. Design and synthesis 73 1.3.3.2. Chemistry 73 1.3.3.3. Biochemistry and biology 77 1.3.3.4. Structure-activity relationships discussion and conclusions 77 1.4. C-6 METHYL DERIVATIVES OF ANDROSTENEDIONE 79 1.4.1. Design and synthesis 79 1.4.2. Chemistry 80 1.4.3. Biochemistry 81 1.4.4. Structure-activity relationships discussion and conclusions 82 1.5. C-7 ALLYL DERIVATIVES OF ANDROSTENEDIONE 84 1.5.1. Design and synthesis 84 1.5.2. Chemistry 85 1.5.3. Biochemistry 86 1.5.4. Structure-activity relationships discussion and conclusions 87 1.6. CONCLUDING STRUCTURE-ACTIVITY RELATIONSHIPS 92 1.7. EXPERIMENTAL SECTION 93 CHAPTER II - STEROIDAL 5α-REDUCTASE INHIBITORS AS ANTI-TUMORS AND AS DRUGS FOR THE TREATMENT OF BENINGN PROSTATE HYPERPLASIA (BPH) 139 INTRODUCTION 143 B.1. Prostate Cancer and Benign Prostate Hyperplasia (BPH): Some Facts 143 B.2. Androgens and 5α-Reductase Enzyme 144 B.3. 5α-Reductase Inhibitors 147 B.3.1. Steroidal 5α-Reductase Inhibitors 147 B.3.2. Nonsteroidal 5α-Reductase Inhibitors 150 AIM OF THE WORK 152 2.1. STEROIDAL C-17 CARBOXY DERIVATIVES 153 2.1.1. Design and synthesis 153 2.1.2. Chemistry 155 2.1.3. Biochemistry and biology 157 2.1.4. Structure-activity relationships discussion and conclusions 157 2.2. EXPERIMENTAL SECTION 161 CHAPTER III - FUTURE WORK: DEVELOPMENT OF COUMARINS AS AROMATASE INHIBITORS 167 INTRODUCTION 171 AIM OF THE WORK 175 3.1. DERIVATIVES OF 3-THIOPHENE COUMARIN 176 3.1.1. Design and Synthesis 176 3.1.2. Chemistry 177 3.2. EXPERIMENTAL SECTION 181 REFERENCES 199 PUBLICATIONS The results presented in this thesis allowed the following publications: Papers published in peer review international journals (ISI Indexed) “New Steroidal 17β-Carboxy Derivatives Present Anti-5α-Reductase Activity and Anti-proliferative Effects in a Human Androgen-Responsive Prostate Cancer Cell Line”, Cristina Amaral, Carla Varela, Georgina Correia-da-Silva, Elisiário Tavares da Silva, Rui A. Carvalho, Saul C. P. Costa, Sara C. Cunha, José O. Fernandes, Natércia Teixeira, Fernanda M. F. Roleira, accepted for publication in Biochimie 2013. “Steroidal Aromatase Inhibitors Inhibit Growth of Hormone-dependent Breast Cancer Cells by Inducing Cell Cycle Arrest and Apoptosis”, Cristina Amaral, Carla Varela, Margarida Borges, Elisiário Tavares da Silva, Fernanda Roleira, Georgina Correia-da-Silva, Natércia Teixeira, in press Apoptosis 2013.
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