Synthesis of isonucleosides 13, 14, 16, and 17, bearing an exocyclic methylidene group at the sugar moiety, starting from a 3-keto sugar is described. The keto compound was converted to the methylene-sugar 10b (Scheme 1), which was coupled with nucleobases by means of the Mitsunobu reaction. The coupling reaction with adenine and 8-azaadenine produced both the N9- and N3-nucleosides (see 13 and 14
Uracil- and thymine-substituted thymidine and uridine derivatives
作者:Anna M. Costa、Montserrat Faja、Jaume Farràs、Jaume Vilarrasa
DOI:10.1016/s0040-4039(98)00100-2
日期:1998.3
The four possible 3′-uracil-1-yl and 3′-thymin-1-yl derivatives of 3′-deoxythymidine and the four analogous derivatives of 2′-deoxyuridine have been synthesised from thymidine and uridine, respectively. Advantages of the 2-(methoxycarbonyl)vinyl group to prevent the formation of anhydronucleosides and of SnCl2/PhSH/Et3N in relation to H2/Pd for the reduction of most azido groups are disclosed.
Synthesis of Nucleosides and Related Compounds. Part XX. Synthesis of Carbocyclic Nucleosides from 2-Azabicyclo(2.2.1)hept-5-en-3-ones: Sodium Borohydride-Mediated Carbon-Nitrogen Bond Cleavage of Five-and Six-Membered Lactams.
Various carbocyclic ribofuranosyl nucleosides were stereoselectively synthesized through a small number of steps from 2-azabicyclo[2.2.1]hept-5-en-3-ones by the use of sodium borohydride-mediated C-N bond cleavage as a key step. Ready availability of a novel synthetic precursor, (±)-4β-hydroxymethyl-1β-ureidocyclopentane-2α, 3α-diol [(±)-carbocyclic ribofuranosylurea], provides not only facile routes to carbocyclic robofuranosylpyrimidines, but also another route to the corresponding cyclopentylamine, (±)-1β-amino-4β-hydroxymethylcyclopentane-2α, 3α-diol [(±)-carbocyclic ribofuranosylamine], which is useful for the synthesis of the corresponding purine nucleosides.
Synthesis of compounds active against HIV. Part 2. Preparation of some 2′,3′-dideoxy-6′-fluorocarbocyclic nucleosides
作者:Diane M. Coe、Peter L. Myers、David M. Parry、Stanley M. Roberts、Richard Storerb
DOI:10.1039/c39900000151
日期:——
A series of 2′,3′-dideoxy-6′-fluorocarbocyclic nucleosides have been prepared and tested for activity againstHIV: compound (20) showed weak antiviral activity.
Synthesis of Nucleosides and Related Compounds. XXII. Carbocyclic Analogues of Thymidine and Related Compounds from 2-Azabicyclo(2.2.1)hept-5-en-3-ones.
Reductive amido bond cleavage reaction, previously elaborated by our laboratory for the synthesis of carbocyclic ribothymidine from readily available 2-azabicyclo[2.2.1]hept-5-en-3-one, was successfully applied to the synthesis of carbocyclic analogues of thymidine and related compounds.