25600-23-1Relevant academic research and scientific papers
Access to oxetane-containing psico-nucleosides from 2-methyleneoxetanes: A role for neighboring group participation?
Liang, Yanke,Hnatiuk, Nathan,Rowley, John M.,Whiting, Bryan T.,Coates, Geoffrey W.,Rablen, Paul R.,Morton, Martha,Howell, Amy R.
experimental part, p. 9962 - 9974 (2012/02/05)
The first psico-oxetanocin analogue of the powerful antiviral natural product, oxetanocin A, has been readily synthesized from cis-2-butene-1,4-diol. Key 2-methyleneoxetane precursors were derived from β-lactones prepared by the carbonylation of epoxides. F+-mediated nucleobase incorporation provided the corresponding nucleosides in good yield but with low diastereoselectivity. Surprisingly, attempted exploitation of anchimeric assistance to increase the selectivity was not fruitful. A range of 2-methyleneoxetane and related 2-methylenetetrahydrofuran substrates was prepared to explore the basis for this. With one exception, these substrates also showed little stereoselectivity in nucleobase incorporation. Computational studies were undertaken to examine if neighboring group participation involving fused [4.2.0] or [4.3.0] intermediates is favorable (Figure presented).
Synthesis of 1′,2′-cis-Nucleoside analogues: Evidence of stereoelectronic control for SN2 reactions at the anomeric center of furanosides
Prevost, Michel,St-Jean, Olivier,Guindon, Yvan
supporting information; experimental part, p. 12433 - 12439 (2010/11/03)
We are reporting a highly diastereoselective route to 1′,2′- cis-nucleoside analogues in the d-ribo, d-lyxo, d-xylo, and d-arabinoside series. Five-membered ring lactols undergo highly selective N-glycosidation reactions in the presence of dimethylboron bromide with different silylated nucleobases. Stereoelectronic control plays a crucial role for the observed induction, and the products are proposed to be formed through SN2 "exploded" transition states. This approach shows great potential considering its simplicity and selectivity for the synthesis of nucleoside analogues, an important class of molecules in medicinal chemistry.
Oxidation of Alkyl Trimethylsilyl Ketene Acetals with Lead(IV)
Rubottom, George M.,Gruber, John M.,Marrero, Roberto,Juve, Henrik D.,Kim, Wan Chong
, p. 4940 - 4944 (2007/10/02)
Alkyl trimethylsilyl ketene acetals generated from either esters or lactones react with lead(IV) acetate (LTA) or lead(IV) benzoate (LTB) to afford useful yields of the corresponding α-carboyloxy esters and α-carboyloxy lactones.Yields of the reaction products are optimized by use of the appropriate solvent (methylene chloride or benzene) during oxidation.Alkyl groups such as methyl, ethyl, and tert-butyl are all compatible with the procedure, and lactones containing five-, six-, and seven-membered rings give good yields of oxidation products.
