The association between cardiovascular reactivity and the metabolic syndrome, as well as individual metabolic syndrome criterion variables, was investigated in adolescents. Cardiovascular reactivity has been examined as a risk marker or factor in the pathogenesis of hypertension or cardiovascular disease, but few studies have looked at its relationship with the metabolic syndrome. Blood pressure (BP) and heart rate (HR) cardiovascular reactivity to three tasks, evaluated speaking, mirror star tracing, and cold pressor, were assessed in 148 adolescents. Using the American Heart Association (AHA) adult definitional criteria, individuals were classified into metabolic syndrome groups (presence vs. absence of metabolic syndrome), and 16% of individuals met criteria for the metabolic syndrome. In logistic regression analyses, the occurrence of the metabolic syndrome was negatively associated with HR reactivity to the cold pressor (OR = 0.920, 95% CI = 0.873, 0.969), and positively associated with diastolic blood pressure (DBP) reactivity to the star tracing task (OR = 1.089, 95% CI = 1.008, 1.177). Results of multiple regression analyses that included individual metabolic syndrome risk variables indicated that cold pressor reactivity explained 7% of the variance in casual BP, while star tracing reactivity accounted for 7% of the variance waist circumference and 6% of the variance triglycerides (ps < .05). The findings indicate that cardiovascular reactivity to physical or behavioral challenge is associated with the metabolic syndrome in a sample of adolescents. Cardiovascular reactivity may be an important clinical tool for identifying individuals at risk of the metabolic syndrome and cardiovascular disease.

In this thesis, two rather different types of problems were investigated. The first was a case of anomalous reactivity in the area of carbohydrate synthesis. Hexopyranosides having the galacto configuration (i.e. C-4?OR axial) display very low SN2 reactivities towards anionic nucleophiles, whereas the corresponding gluco-configured C-6 sulfonates (C-4?OR equatorial) react at rates typical of primary centers. The accepted explanation for this difference involves the repulsive interaction of local dipoles in the transition structure of the galacto compound. This interaction is thought to destabilize the transition structure, making this reaction difficult. However, there are numerous inconsistencies in the application of this simple model (cases where the model fails to predict the observed behavior). Thus, a computational project was undertaken to examine six model systems of this type. The energetics and equilibria of the reactants were determined, including solvation. Reaction pathways and kinetics for various displacements were computed. Analyses of the calculated charge densities allowed for evaluation of any electrostatic interactions. This study revealed a number of important factors affecting the rates of reaction, while clearly showing that dipole-dipole interactions are very limited in these systems. The second project was in the related areas of molecular polarizability and vibrational spectroscopy. Descriptive models have been sought relating the structure and connectivity of molecules to their electronic properties. Researchers in the areas of non-linear optics and of conducting polymers require a better understanding of the effects of structural variations on electronic properties. The 4 simplest models of molecular polarizability and its derivatives with respect to molecular vibrations are grossly inadequate. The highest-level calculations are generally reliable but are not applicable to even moderately sized systems. Thus trends in these properties were investigated for a large series of molecules. Calculations were performed at a variety of theoretical levels in order to determine the ranges of predicted behavior. Since these calculations predicted unusual properties in bicyclo-[1.1.1]-pentane, an experimental project was completed on this molecule. The results of Raman scattering intensity experiments on bicyclo-[1.1.1]-pentane allowed for evaluation of the performance of various computational methods. More importantly, it allowed for the confirmation of some qualitative structure/property relationships. / October 2004

No description available.

No description available.

In this thesis, two rather different types of problems were investigated. The first was a case of anomalous reactivity in the area of carbohydrate synthesis. Hexopyranosides having the galacto configuration (i.e. C-4?OR axial) display very low SN2 reactivities towards anionic nucleophiles, whereas the corresponding gluco-configured C-6 sulfonates (C-4?OR equatorial) react at rates typical of primary centers. The accepted explanation for this difference involves the repulsive interaction of local dipoles in the transition structure of the galacto compound. This interaction is thought to destabilize the transition structure, making this reaction difficult. However, there are numerous inconsistencies in the application of this simple model (cases where the model fails to predict the observed behavior). Thus, a computational project was undertaken to examine six model systems of this type. The energetics and equilibria of the reactants were determined, including solvation. Reaction pathways and kinetics for various displacements were computed. Analyses of the calculated charge densities allowed for evaluation of any electrostatic interactions. This study revealed a number of important factors affecting the rates of reaction, while clearly showing that dipole-dipole interactions are very limited in these systems. The second project was in the related areas of molecular polarizability and vibrational spectroscopy. Descriptive models have been sought relating the structure and connectivity of molecules to their electronic properties. Researchers in the areas of non-linear optics and of conducting polymers require a better understanding of the effects of structural variations on electronic properties. The 4 simplest models of molecular polarizability and its derivatives with respect to molecular vibrations are grossly inadequate. The highest-level calculations are generally reliable but are not applicable to even moderately sized systems. Thus trends in these properties were investigated for a large series of molecules. Calculations were performed at a variety of theoretical levels in order to determine the ranges of predicted behavior. Since these calculations predicted unusual properties in bicyclo-[1.1.1]-pentane, an experimental project was completed on this molecule. The results of Raman scattering intensity experiments on bicyclo-[1.1.1]-pentane allowed for evaluation of the performance of various computational methods. More importantly, it allowed for the confirmation of some qualitative structure/property relationships.

No description available.

In this thesis, two rather different types of problems were investigated. The first was a case of anomalous reactivity in the area of carbohydrate synthesis. Hexopyranosides having the galacto configuration (i.e. C-4?OR axial) display very low SN2 reactivities towards anionic nucleophiles, whereas the corresponding gluco-configured C-6 sulfonates (C-4?OR equatorial) react at rates typical of primary centers. The accepted explanation for this difference involves the repulsive interaction of local dipoles in the transition structure of the galacto compound. This interaction is thought to destabilize the transition structure, making this reaction difficult. However, there are numerous inconsistencies in the application of this simple model (cases where the model fails to predict the observed behavior). Thus, a computational project was undertaken to examine six model systems of this type. The energetics and equilibria of the reactants were determined, including solvation. Reaction pathways and kinetics for various displacements were computed. Analyses of the calculated charge densities allowed for evaluation of any electrostatic interactions. This study revealed a number of important factors affecting the rates of reaction, while clearly showing that dipole-dipole interactions are very limited in these systems. The second project was in the related areas of molecular polarizability and vibrational spectroscopy. Descriptive models have been sought relating the structure and connectivity of molecules to their electronic properties. Researchers in the areas of non-linear optics and of conducting polymers require a better understanding of the effects of structural variations on electronic properties. The 4 simplest models of molecular polarizability and its derivatives with respect to molecular vibrations are grossly inadequate. The highest-level calculations are generally reliable but are not applicable to even moderately sized systems. Thus trends in these properties were investigated for a large series of molecules. Calculations were performed at a variety of theoretical levels in order to determine the ranges of predicted behavior. Since these calculations predicted unusual properties in bicyclo-[1.1.1]-pentane, an experimental project was completed on this molecule. The results of Raman scattering intensity experiments on bicyclo-[1.1.1]-pentane allowed for evaluation of the performance of various computational methods. More importantly, it allowed for the confirmation of some qualitative structure/property relationships.

Graduation date: 1994

Thesis (Ph. D.)--State University of New York at Binghamton, Chemistry Department, 2006. / Includes bibliographical references.

The existence of the reactive intermediate trans-10b,10c-dimethyl-10b,10c-dihydropyr-1-yne, 57, generated via dehydrobromination, was proved by trapping with N,N-diethyl-1,3-butadienylamine, furan and a series of isoannelated furans. Comparison of 57 with benzyne, 1, was implemented using the results of MMX/PCMODEL calculations. A fast route to annelated dihydropyrenes was developed via the reactive intermediate 57. Through this route, five annelated dihydropyrenes, namely, trans-14b,14c-dimethyl-14b,14c-dihydronaphtho (2,1,8-gra) naphthacene, 204, trans-16b,16c-dimethyl-16b,16c-dihydrobenzo (a) naphtho (2,1,8-fgh) naphthacene, 206a, trans-16b,16c-dimethyl-16b,16c-dihydrobenzo (a) naphtho (2,1,8-hij) naphthacene, 206b, trans-14b,14c,18b,18c-tetramethyl-14b,14c,18b, 18c-tetrahydrodinaphtho (2,1,8-uva; 2,1,8-jkl) pentacene, 224a, and trans-15b,15c,18b,18c-tetramethyl-15b,15c,18b, 18c-tetrahydrodinaphtho (2,1,8-uva; 2,1,8-pon) pentacene, 224b, and one bridged oxa (17) annulene, namely, trans-11b,11c-dimethyl-11b,11c-dihydropyreno (1,2-c) furan, 222, were synthesized. Metal complexation of the benzo (a) dihydropyrene 95 was investigated. This led to the first two metal dihydropyrene complexes, namely, (7,8,9,10,10a,10b-η6)-trans-12b,12c-dimethyl-12b,12c-dihydrobenzo (a) pyrenechromium(0)-tricarbonyl, 239, and (1,2,3,3a-η4) -trans-12b,12c-dimethyl-12b,12c-dihydrobenzo (a) pyreneiron(0)tricarbonyl, 209. The delocalization effects due to complexation were studied. Combining the results of the newly synthesized annelated dihydropyrenes with previously obtained ones, a series of correlations between theoretical calculations and experimental results, such as bond order vs. chemical shift, bond order vs. coupling constant, and ring current vs. chemical shift were devised. The ortho-metalation of dihydropyrene derivatives and synthesis of 1-bromo-2-fluoro-dihydropyrene were attempted. This led to two new dihydropyrene derivatives, namely, trimethylacetamino-trans-10b,10c-dimethyl-10b,10c-dihydropyrene, 99, and 2-diethylcarbamyl-trans-10b,10c-dimethyl-10b,10c-dihydropyrene, 109, and two new cyclophane derivatives, namely, syn-5-bromo-6-fluoro-9,18-dimethyl-2,11-dithia (3.3) metacyclophane, 131a, and anti-5-bromo-6-fluoro-9,18-dimethyl-2,11-dithia (3.3) metacyclophane, 131b. / Graduate