In his thesis, Kiyoun Lee describes his studies into tandem and organocatalytic oxa-conjugate addition reactions for the synthesis of complex tetrahydropyrans (THP). Readers gain insight into the new methods Lee employs for the synthesis of biologically interesting natural products including (+)-leucascandrolide A, (+)-dactylolide, and (+-)diospongin A. The reactions Lee investigates are applicable to a broad range of substrates and proceed with excellent stereoselectivity. Moreover, the methodologies allow the synthesis of a wide range of THP-containing compounds. The development of reactions, such as those discussed by Lee, has the potential to impact natural product synthesis, pharmaceutical development and chemical biology.
A unique guide to variable temperature CD spectroscopy and its application in organic chemistry<br> This timely, original, thought-provoking work looks at organic stereochemistry from the perspective of circular dichroism (CD), using variable temperature CD spectroscopy to determine the conformation or absolute configuration of chiral molecules. With an emphasis on the analysis of optically active ketones and the carbonyl chromophore, the authors demonstrate the advantages of this highly sensitive spectroscopic tool for obtaining stereochemical information in diverse areas of organic chemistry, biochemistry, and medicinal/pharmaceutical chemistry. They combine detailed examples of stereochemical analysis with clear, thorough presentations, correlating chiroptical data with molecular mechanics calculations as well as data from NMR spectroscopy and other spectroscopic techniques. In addition, they provide a systematic survey of the professional literature, featuring an extraordinary collection of original CD spectra run at varying temperatures. Coverage includes:<br> * Chiroptical measurements: CD and ORD (Optical Rotatory Dispersion)<br> * Conformational analysis of compounds ranging from simple cyclic ketones to polycyclics<br> * Conjugated and homoconjugated systems<br> * Stereochemistry of the carbon-carbon double bond<br> * Stereochemistry from exciton coupling of two or more chromophores<br> * An interesting historical account of the development of stereochemical concepts
This collection of twenty-six articles by leading experts is the first truly comprehensive account of the gas-phase electron diffraction technique. It is written for the non-specialist users of structural information.<br> <br> Part A discusses the development and present capabilities of gas electron diffraction. Several contributions deal with the combined application of various techniques. Part B contains the structural information and also presents trends and interpretations of structural variations.