La represión sexual como tema recurrente en la obra de Federico García Lorca

The purpose of this dissertation is to demonstrate that sexual repression is a recurring theme throughout a selection of works by Federico García Lorca. The introductory chapter focuses on the sexual theories of Sigmund Freud and Michel Foucault in setting the foundation for an analysis of sexually frustrated characters. In chapter two, an analysis of Lorca's rural trilogy reveals how marginalized female characters struggle to preserve societal customs that subjugate them to the patriarchal hegemony by limiting their free will and their sexual freedom. The subsequent chapter elaborates on the theme of repression in poems where the oppressed voice expresses and denounces the intolerance and persecution of those who condemn homosexuality through metaphors of darkness, impurity, and barren love. Chapter four analyzes two avant-garde plays where the underlying message is that of a society that hampers the expression of homosexual love by silencing desire and forcing individuals to mask their identities. The conclusion demonstrates once more the effects of society on sexual freedom, as well as explaining that the recurrence of repressed women is not a pretext in portraying the homosexual saga, but a pre-text in presenting them as an equally marginalized group.

Relative basicities of free base porphyrins; understanding the role of macrocyclic distortion

Porphyrins have been the center of numerous investigations in different areas of chemistry, geochemistry, and the life sciences. In nature the conformation of the porphyrin macrocycle varies, depending on the function of its apoenzyme. It is believed that the conformation of the porphyrin ring is necessary for the enzyme to achieve its function and modify its reactivity. It is important to understand how the conformation of the porphyrin ring will influence its properties. ^ In synthetic porphyrins particular conformations and ring deformations can be achieved by peripheral substitution, metallation, core substitution, and core protonation among other alterations of the macrocycle. The macrocyclic distortions will affect the ring current, the ability of pyrroles to intramolecularly hydrogen bond and the relative basicity of each of the porphyrins. To understand these effects different theoretical models are used. The ground state structure of each of 19 free base porphyrins is determined using molecular mechanics (MM+) and semiempirical methods (PM3). The energetics of deformation of the macrocyclic core is calculated by carrying out single point energy calculations for the conformation achieved by each synthetic compound. Enthalpies of solution and enthalpies of protonation of 10 porphyrins with varying degrees of macrocyclic deformation and varying electron withdrawing groups in the periphery are determined using solution calorimetry. Using Hess's Law, the relative basicity of each of the different free base porphyrins is calculated. NMR results are described, including the determination of free energies of activation of ring tautomerization and hydrogen bonding for several compounds. It was found that in the absence of electronic effects, the greater macrocyclic deformation, the greater the basicity of the porphyrins. This basicity is attenuated by the presence of electron withdrawing groups and ability to of the macrocycle to intramolecularly hydrogen bond. ^

Relative basicities of free base porphyrins : understanding the role of macrocyclic distortion

Porphyrins have been the center of numerous investigations in different areas of chemistry, geochemistry, and the life sciences. In nature the conformation of the porphyrin macrocycle varies, depending on the function of its apoenzyme. It is believed that the conformation of the porphyrin ring is necessary for the enzyme to achieve its function and modify its reactivity. It is important to understand how the conformation of the porphyrin ring will influence its properties. In synthetic porphyrins particular conformations and ring deformations can be achieved by peripheral substitution, metallation, core substitution, and core protonation among other alterations of the macrocycle. The macrocyclic distortions will affect the ring current, the ability of pyrroles to intramolecularly hydrogen bond and the relative basicity of each of the porphyrins. To understand these effects different theoretical models are used. The ground state structure of each of 19 free base porphyrins is determined using molecular mechanics (MM+) and semiempirical methods (PM3). The energetics of deformation of the macrocyclic core is calculated by carrying out single point energy calculations for the conformation achieved by each synthetic compound. Enthalpies of solution and enthalpies of protonation of 10 porphyrins with varying degrees of macrocyclic deformation and varying electron withdrawing groups in the periphery are determined using solution calorimetry. Using Hess's Law, the relative basicity of each of the different free base porphyrins is calculated. NMR results are described, including the determination of free energies of activation of ring tautomerization and hydrogen bonding for several compounds. It was found that in the absence of electronic effects, the greater macrocyclic deformation, the greater the basicity of the porphyrins. This basicity is attenuated by the presence of electron withdrawing groups and ability to of the macrocycle to intramolecularly hydrogen bond.