8- 2ReO

The first synthesis of d4T was accomplished in 1966 by Horwitz from l-(2-deoxy-3,5-epoxy-/3-D-r/2reo-pentosyl)thymine abstraction of a proton from the 2 -position by potassium butoxide in DMSO resulted in an opening of the oxetane ring and formation of d4T. Other syntheses were based on the elimination of sulfoxide or the selenoxide moiety placed at the C-2 position in the nucleoside, which was prepared from cheap lactone 6 (O Scheme 7) [6]. 

Along the same line, Miyake and co-workers have developed a class of Ci-symmetric systems which are highly isospecific (e.g. i/2reo-Me2C(3-f-Bu-Cp)(3-f-Bu-... 

Fig. 2. Hammett treatment of the acetolysis of t/2reo-3-aryl-2-butyl p-bromobenzene-sulfonates. Reproduced by permission of John Wiley and Sons.

Small amounts of Re substituted for Ru into URu2Si2 rapidly suppress superconductivity and induce ferromagnetic interactions. Neutron studies by Torikachvili et al. (1992) on polycrystalline material were able to show ferromagnetic order in U(Rui 2Reo,g)Si2 of 0.5 jUB> but could not draw any conclusions about the inelastic magnetic response. 

When 5-bromo-2,5-dideoxy-D-t/2reo-pentonolactone (1) (Scheme 4) was treated with aqueous potassium hydroxide and subsequently acidified, 2-deoxy-L-eryt/2ro-pentono-l,4-lactone (2-deoxy-L-ribonolactone) (2) was formed and isolated as the crystalline benzoate [17]. A stereospecific inversion at C-4 had... 

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