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11	Synthesis and structure of microbial siderophores (iron chelators) Schwartz, B. D. Unknown Date (has links) No description available. 250302 Biological and Medical Chemistry 780103 Chemical sciences
12	Structure and Synthesis in Natural Product Chemistry Gallagher, O. P. Unknown Date (has links) No description available. 780103 Chemical sciences
13	Synthesis and structure of racemic and non-racemic natural products including allenes McGrath, M. Unknown Date (has links) No description available. 780103 Chemical sciences
14	Fatty acid metabolism by cytochromes P450 Cryle, M. J. Unknown Date (has links) No description available. 780103 Chemical sciences
15	Synthesis and structure of racemic and non-racemic natural products including allenes McGrath, M. Unknown Date (has links) No description available. 780103 Chemical sciences
16	Syntheses and reactions of iminopropadienones, sydnones and oxazinones. Veedu, Rakesh Naduvile Unknown Date (has links) Iminorpropadienones (R-N=C=C=C=O) 1.2, are a new class of linear cumulenes, usually generated by Flash Vacuum Thermolysis and characterised by IR spectroscopy in low temperature matrices. New derivates of iminopropadienones viz. 3-pyridyl 1.15, 4-pyridyl 1.16, pentafluorophenyl 1.17 and [alpha]-naphthyliminopropadienone 1.18 are synthesised and characterised. Pentafluorophenyl and [alpha]-naphthyliminopropadienones are characterised both by IR and [superscript]13C NMR spectroscopy as they are found to be more stable, and [alpha]-naphthyliminopropadienones can even be isolated at room temperature. Chemical reaction of several iminopropadienones with nucleophiles such as dimethylamine (DMA), diethylamine (DEA) and trimethylamine (TMA) were studied. The analytical FVT experiments provided direct evidence for the nucleophilic attack on both the C=O and N=C moities of the iminopropadienones to give ketenes and ketenimines. Zwitterions were observed in all reactions with TMA. Preparative FVT trapping experiments of 3-pyridyl and 4-pyridyliminopropadienones with nucleophiles allowed the isolation of naphthyridones as the stable end product. Photochemistry of N-phenylsydnone 2.4, N-(3-pyridyl)sydnone 2.6 and diphenylsydnone 2.23 was investigated in Ar matrix. On irradiation 2.4 and 2.6 afforded similar products viz. 2-oxa-1,5-diaza-bicyclo[2.1.0]pentan-3-ones 2.9a and 2.9b, N-nitrosoaminoketenes 2.10a and 2.10b, carbodiimides 2.12a and 2.12b, and nitrilimines 2.13a and 2.13b. Diphenylsydnone behaved differently on irradiation by forming diphenylcarbodiimide 2.24 and benzonitrile 2.25. Flash Vacuum Thermolysis chemistry of newly synthesised and characterised oxazinone derivatives, namely 4-hydroxy-2,5-diphenyl-[1,3]-oxazin-6-one 3.4 4-hydroxy-2-isopropenyl-5-phenyl-[1,3]-oxazin-6-one 3.5 and 4-methoxy-2,5-diphenyl-[1,3]-oxazin-6-one 3.6 was investigated. On FVT 3.4 and 3.5 behaved in the same manner by forming phenylketene 3.7, whereas 3.6 did not afford 3.7, as it cannot tautomerize and hence it cannot undego this fragmentation reaction on FVT. Read more 780103 Chemical sciences
17	Structure and Synthesis in Natural Product Chemistry Gallagher, O. P. Unknown Date (has links) No description available. 780103 Chemical sciences
18	Syntheses and reactions of iminopropadienones, sydnones and oxazinones. Veedu, Rakesh Naduvile Unknown Date (has links) Iminorpropadienones (R-N=C=C=C=O) 1.2, are a new class of linear cumulenes, usually generated by Flash Vacuum Thermolysis and characterised by IR spectroscopy in low temperature matrices. New derivates of iminopropadienones viz. 3-pyridyl 1.15, 4-pyridyl 1.16, pentafluorophenyl 1.17 and [alpha]-naphthyliminopropadienone 1.18 are synthesised and characterised. Pentafluorophenyl and [alpha]-naphthyliminopropadienones are characterised both by IR and [superscript]13C NMR spectroscopy as they are found to be more stable, and [alpha]-naphthyliminopropadienones can even be isolated at room temperature. Chemical reaction of several iminopropadienones with nucleophiles such as dimethylamine (DMA), diethylamine (DEA) and trimethylamine (TMA) were studied. The analytical FVT experiments provided direct evidence for the nucleophilic attack on both the C=O and N=C moities of the iminopropadienones to give ketenes and ketenimines. Zwitterions were observed in all reactions with TMA. Preparative FVT trapping experiments of 3-pyridyl and 4-pyridyliminopropadienones with nucleophiles allowed the isolation of naphthyridones as the stable end product. Photochemistry of N-phenylsydnone 2.4, N-(3-pyridyl)sydnone 2.6 and diphenylsydnone 2.23 was investigated in Ar matrix. On irradiation 2.4 and 2.6 afforded similar products viz. 2-oxa-1,5-diaza-bicyclo[2.1.0]pentan-3-ones 2.9a and 2.9b, N-nitrosoaminoketenes 2.10a and 2.10b, carbodiimides 2.12a and 2.12b, and nitrilimines 2.13a and 2.13b. Diphenylsydnone behaved differently on irradiation by forming diphenylcarbodiimide 2.24 and benzonitrile 2.25. Flash Vacuum Thermolysis chemistry of newly synthesised and characterised oxazinone derivatives, namely 4-hydroxy-2,5-diphenyl-[1,3]-oxazin-6-one 3.4 4-hydroxy-2-isopropenyl-5-phenyl-[1,3]-oxazin-6-one 3.5 and 4-methoxy-2,5-diphenyl-[1,3]-oxazin-6-one 3.6 was investigated. On FVT 3.4 and 3.5 behaved in the same manner by forming phenylketene 3.7, whereas 3.6 did not afford 3.7, as it cannot tautomerize and hence it cannot undego this fragmentation reaction on FVT. Read more 780103 Chemical sciences
19	Numerical Methods in Reaction Rate Theory Frankcombe, Terry James Unknown Date (has links) Numerical methods are often required to solve chemical problems, either to verify theoretical models or to access information that is not readily available experimentally. This thesis deals with both situations, though in differing levels of detail. A major component of this thesis is devoted to developing new methods to determine a full eigendecomposition of the matrices derived from "low temperature" unimolecular master equations. When transient behaviour is of interest achieving relative accuracy for more than just the eigenvector corresponding to the smallest eigenvalue is of central importance. Three new methods are presented. The first is based on a weighted implementation of subspace projection methods, in this case explored for the well-known Arnoldi method. This weighted inner product subspace projection methodology is demonstrated to 780103 Chemical sciences master equation matrix methods EGME gas phase nonequilibrium kinetics spectral eigenvalues eigenvectors HONE ERS Nesbet WIPSP subspace projection relative accuracy precision MPFUN quadruple precision double precision Chebyshev Lanczos Arnoldi coal graphene carbon ab initio B3LYP gasification
20	Numerical Methods in Reaction Rate Theory Frankcombe, Terry James Unknown Date (has links) Numerical methods are often required to solve chemical problems, either to verify theoretical models or to access information that is not readily available experimentally. This thesis deals with both situations, though in differing levels of detail. A major component of this thesis is devoted to developing new methods to determine a full eigendecomposition of the matrices derived from "low temperature" unimolecular master equations. When transient behaviour is of interest achieving relative accuracy for more than just the eigenvector corresponding to the smallest eigenvalue is of central importance. Three new methods are presented. The first is based on a weighted implementation of subspace projection methods, in this case explored for the well-known Arnoldi method. This weighted inner product subspace projection methodology is demonstrated to 780103 Chemical sciences master equation matrix methods EGME gas phase nonequilibrium kinetics spectral eigenvalues eigenvectors HONE ERS Nesbet WIPSP subspace projection relative accuracy precision MPFUN quadruple precision double precision Chebyshev Lanczos Arnoldi coal graphene carbon ab initio B3LYP gasification

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