Donor reactivities

Orosz CG Mechanisms of graft acceptance evidence that plasminogen activator controls donor-reactive delayed-type hypersensitivity responses in cardiac allograft acceptor mice. J Immunol 2000 164 5132-5139. 

Yasui, S. Tsujimoto, M. Okamura, M. Ohno, A. Stereoelectronic effeds on the one-electron donor reactivity of trivalent phosphorus compounds. Experimental and theoretical investigations. Bull. Chem. Soc.Jpn. 1998, 71, 927— 932. 

INFLUENCE OF HYDROXY PROTECTING GROUPS ON SIALYL DONOR REACTIVITY 147... 

Scheme 1 Acceptor and donor reactivity of lithium halocarbenoids...

Firstly, the reactivity of the glycosyl donor can be varied over wide ranges by the choice of the halogen, the protecting group pattern, the catalyst, the solvent and the temperature. In this way the glycosyl donor reactivity can be adjusted to the glycosyl acceptor reactivity (which can also be varied). 

The type of activated donor substrate used in a glycosidase-catalyzed reaction can greatly influence several important factors such as donor reactivity, solubility, reaction yields and propensity for donor self-condensation reactions. The accessibility of the donor substrates also needs to be considered. 

The geometrical relaxations, in response to displacements in the electronic structure of the acid-base (acceptor-donor) reactive system, are also the subject of the intuitive, structural bond-variation rules of Gutmann [62]. They also follow the above Hellmann-Feynman (electron-preceding) perspective of Nakatsuji, who obtained interesting interrelations between changes in the electron density and nuclear configuration in a variety of contexts associated with chemical reactions. He has shown, for example, that the centroid of a... 

The molecular structure imparts cellulose with its characteristic properties such as hydrophilicity, chirality, degradability, and broad chemical variability initiated by the high donor reactivity of the OH groups. It is also the basis of the extensive hydrogen bond networks, which give cellulose a multitude of partially crystalline fibre structures and morphologies. 

A number of reviews, dealing with the subject of HNO or NO generation, appeared over the past decade. Specifically, two reviews published in 2005 by Miranda and coworkers (10,27) include a deep description of the donor reactivity, as well as the more recent review by Doctorovich and coworkers (1). Here, we will briefly outline the key methods of HNO generation. 

Logically, an extension of this sequence would lead to d" -synthons, for which a few corresponding reagents exist (Scheme 2.9). In practice, compound 4 is likely to display competing d - and d" -reactivity [12], In the case of compound 5, there is no relation of the reactivity at C-4 to the functionality at C-1 rather the acetal moiety is masking the carbonyl group, protecting it from the donor reactivity at C-4. 

Electronically different LGs have also been incorporated to tune the glycosyl donor reactivity (Scheme 6.8). One of the first examples described the use of selenoglycosids in the presence of thioglycosides. While Mehta and Pinto used silver triflate to selectively activate the seleno derivative 34-the benzylated sulfur compound 35 did not react-for the synthesis of disaccharide 36 [38, 39], iodonium sources became more common for numerous applications of this concept in one-pot... 

DON-01 Mean electronic donor reactivity of lone pair... 

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