Spectroscopic and Conformational Studies

and laser Raman spectra have been recorded for cytosine 

Negative-ion FAB mass spectra have been used 

Studies of the solution ordering of guanosine -2 -monophosphate dianlons, with alkali metal ion as structure directors, support the stacked tetramer model for nucleoside ordering. X-ray structures of nucleosides are mentioned in Chapter 22. 

Some structures with similarity to nucleosides are referred to in Chapters 10 and li. 

Evidente, G. Randazzo, G. Surico, and N.S.Iacobellis, 

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HNMR spectroscopic studies4 have confirmed that 4-bromo-l//-3-benzazepin-2-amine exists as the 2-amino tautomer and not as the 2-imino-l,5-dihydro form as suggested earlier.42 HNMR spectral data and conformational studies on 17/-l-bcnzazepines,20 and on 1H-, 3H-, and 5/7-2-benzazepinyl phosphonates43 have been published. 

A detailed spectroscopic and theoretical study of the conformation of dioxolanes 1 has appeared <96T8275>, and a theoretical study has shown that the anomeric effect explains the non-planarity of 1,3-dioxole <96JA9850>. The tetraalkynyldioxolanone 2 has been prepared and its structure and reactivity studied <96HCA634>. Both enantiomers of the chiral glycolic acid equivalent 3 can be prepared from D-mannitol <96HCA1696>, and lipase-mediated kinetic... 

From spectroscopic and biochemical studies it has become clear that DNA-mediated CT is extremely sensitive to the re-stacking of the intervening DNA bases and to disruption and perturbation of the DNA structure or conformation. This indicates that sensing of DNA damage could be accomplished, at least in part, on the basis of CT chemistry. In considering these possibilities, it is important to discover whether DNA-mediated CT does occur within the cell. Charge transfer in HeLa cell nuclei has recently been probed by use of a rhodium photooxidant [15]. 

Emphasis will be placed on recent structural and conformational studies of relatively large molecules, particularly those of biochemical importance. The 1 3 C nmr of carbohydrates, nucleic acids and their constituents, proteins and their residues, lipids and macromolecular model systems will be discussed in detail and attempts will be made to cover the literature exhaustively. This somewhat arbitrary selection is dictated by the availability of recent summaries on 13C spectroscopic measurements of steroids (Gray,... 

Nagano S, Shimada H, Tarumi A, Hishiki T, Kimata-Ariga Y, Egawa T, Suematsu M, Park SY, Adachi S, Shiro Y Ishimura Y (2003) Infrared spectroscopic and mutational studies on putidaredoxin-induced conformational changes in ferrous CO-P450cam. Biochemistry 42 14507-14514... 

Detailed structural, spectroscopic, and computational studies on [Ru([n]aneS4)(2,2 -bipyridyl)][PF6]2 have concluded that the conformations of the macrocycles are determined by steric rather than electronic effects in these crowded cations and that the dynamic processes in solution previously attributed to reversible dissociation are in fact because of pyramidal sulfur inversion. ... 

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