Ringli, Walter

Ringli, Walter, Bromierungen mit Bromosuccinimid, Zurich, Leeman, 1948. 

Hakkinen, H., Walter, M. and Gronbeck, H. (2006) Divide and Protect Capping Gold Nanoclusters with Molecular Gold-Thiolate Rings. The Journal of Physical Chemistry B, 110, 9927-9931. 

For a review of a nitrogen analog, see Boeckman Walters Adv. Heterocycl. Nat. Prod. Synth. 1990,1, 1-41. "For reviews of ring expansions of aziridines, see Heine Mech. Mol. Migr. 1971, 3, 145-176 Dermer Ham Ethylenimine and Other Aziridines Academic Press New York, 1969, pp. 282-290. See also Wong et at.. Ref. 114, pp. 190-192. 

Using methods similar to Fischer s, the straight-chain form of any monosaccharide can be worked out. As we have seen, however, monosaccharides exist mostly as cyclic pyra-nose or furanose hemiacetals. These hemiacetals are in equilibrium with the open-chain forms, so sugars can react like hemiacetals or like ketones and aldehydes. How can we freeze this equilibrium and determine the optimum ring size for any given sugar Sir Walter Haworth (inventor of the Haworth projection) used some simple chemistry to determine the pyranose structure of glucose in 1926. 

M. A. Walters Five membered ring systems With more than one N atom 1997PHC(9)148... 

Expanded studies in this direction revealed that chlorination of the quinoline and phenyl rings in 2-aryl-4-quinolinyl-2 -piperidinyl methanols may diminish phototoxicity [49]. Further molecular modifications in 2-substituted quinine derivatives showed that replacement of the 2-phenyl group by trifluoromethyl groups could further reduce phototoxicity with retention of antimalarial activity [50]. This observation was systematically exploited at the Walter Reed Army Research Institute culminating in the discovery of mefloquine (23a) [51]. The other effective anhmalarials,... 

FIGURE 36 Crystal structure of the anionic cluster [Cps Yb6(N3) ] (left) and the chair-like 12-membered Yb4Ns ring shown on the right. The Cp ligands are removed for clarity (redrawn after Walter et al., 2006). 

Walters, M.A. et al.. Templates for exploratory library preparation. Derivatization of a functionalized spirocyclic 3,6-dihydro-2H-pyran formed by ring-closing metathesis reaction, J. Comb. Chem., 4,125, 2002. 

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