Maximally Substituted Hexa spirotetrahydrofuranyl -cyclohexanes

Reinstallation of the fractured spiro ring can be accomplished either directly at the enone level or, more interestingly, after the ketone carbonyl has been capped as in 36. When 36 and stereoisomers thereof are individually subjected to intramolecular oxymercuration, the stereochemical course of the cyclization is dictated by the approach of Hg2+ to that surface of the double bond where coordination to a proximal axially oriented ether oxygen can operate. [31] Where 37 and 40 are concerned, 

What does the future hold With specific regard to 51, one may ask whether ligation of an oxygen triad to Li+ will be adequate to hold conformation while chemical transformations are performed on the opposite surface If not, can systematic dismantling of the ortho ester bridge provide opportunities for chemical change without incurring chair-to-chair interconversion Since no precedence exists in these areas, the future holds considerable excitement. 

The torsion angles around the bonds of the sugar-phosphate DNA backbone are of decisive importance for the secondary structure of DNA as well as for base-base recognition. [44] For antisense agents to be effective inhibitors of protein expression in vivo, they have to resist the action of DNA-degrading enzymes and bind to their 

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