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This book reviews advances in understanding phosphodiesterases within the central nervous system and their therapeutic applications. A range of expert authors from both academia and industry describe these, then focus on the areas of greatest scientific and medical interest to provide more detailed coverage. Therapeutic and drug discovery applications are covered for diseases including Alzheimer's, Parkinson's, schizophrenia, erectile dysfunction, and spinal cord injuries. There is also a chapter on drug discovery tools such as in vitro assays and X-ray structures for medicinal chemistry studies.

As the only stable baryon, the nucleon is of crucial importance in particle physics. Since the nucleon is a building block for all atomic nuclei, there is a need to analyse the its structure in order to fully understand the essential properties of all atomic nuclei. After more than forty years of research on the nucleon, both the experimental and theoretical situations have matured to a point where a synthesis of the results becomes indispensable. Here, A.W. Thomas and W. Weise present a unique report on the extensive empirical studies, theoretical foundations and the different models of the nucleon. The appendices provide an extensive summary of formulae needed in practical calculations. From the contents: electromagnetic structure of the nucleon, weak probes of nucleon structure, deep inelastic lepton scattering on the nucleon; elements of QCD, aspects of non-perturbative QCD, Chiral Symmetry and nucleon structure, models of the nucleon

Compiles current tested and proven approaches to synthesize novel nucleoside analogues Featuring contributions from leading synthetic chemists from around the world, this book brings together and describes tested and proven approaches for the chemical synthesis of common families of nucleoside analogues. Readers will learn to create new nucleoside analogues with desired therapeutic properties by using a variety of methods to chemically modify natural nucleosides, including: Changes to the heterocyclic base Modification of substituents at the sugar ring Replacement of the furanose ring by a different carbo- or heterocyclic ring Introduction of conformational restrictions Synthesis of enantiomers Preparation of hydrolitically stable C-nucleosides Chemical Synthesis of Nucleoside Analogues covers all the major classes of nucleosides, including pronucleotides, C-nucleosides, carbanucleosides, and PNA monomers which have shown great promise as starting points for the synthesis of nucleoside analogues. The book also includes experimental procedures for key reactions related to the synthesis of nucleoside analogues, providing a valuable tool for the preparation of a number of different compounds. Throughout the book, chemical schemes and figures help readers better understand the chemical structures of nucleoside analogues and the methods used to synthesize them. Extensive references serve as a gateway to the growing body of original research studies and reviews in the field. Synthetically modified nucleosides have proven their value as therapeutic drugs, in particular as antiviral and antitumor agents. However, many of these nucleoside analogues have undesirable side effects. With Chemical Synthesis of Nucleoside Analogues as their guide, researchers have a new tool for synthesizing a new generation of nucleoside analogues that can be used as therapeutic drugs with fewer unwanted side effects.

This book provides a comprehensive overview of nucleophilic aromatic substitutions, focusing on the mechanistic and synthetic features that govern these reactions. The first chapter presents a detailed mechanistic analysis of the factors determining the feasibility of SNAr substitutions, providing decisive information to predict regioselectivity of many reactions and to define the conditions for concerted SNAr processes. Reflecting the key role played by these species as intermediates in most SNAr reactions, chapter 2 then discusses the chemistry of anionic sigma-complexes. Chapter 3 describes the concept of superelectrophilicity in SNAr substitutions, as it has recently emerged from the reactivity of strongly electron-deficient aromatic and heteroaromatic structures. The numerous synthetic applications are considered in depth in the chapters 4 and 5 that follow on intermolecular and intramolecular nucleophilic aromatic substitutions. Then, chapter 6 focuses on substitutions proceeding formally through displacement of a hydride ion, a hot topic in the field. The final chapter brings together concise yet comprehensive discussions surrounding SNAr photosubstitutions, radical substitutions, and ANRORC substitutions. Authored by a highly respected chemist who has contributed greatly to the field over the past two decades, this is a valuable information source for all organic chemists working in academia or the pharmaceutical and agrochemical industries.