Addition of pseudohalogens to unsaturated carbohydrates. VI. Synthesis of 4′ -thiocordycepin

Abstract

The addition of the pseudohalogen iodine nitrate (IONO2) to the endocyclic alkenic bond in benzyl 2-O-benzyl-3,4-dideoxy-α-D-glycero-pent-3-enopyranoside (3) is described. The stereochemistry and regiochemistry of addition were elucidated by chemical degradation, 1Hmr spectroscopy, mass-spectral analysis, and polarimetry. A synthetic route to 4′-thiocordycepin (20) from compound 3, by way of the intermediacy of the preponderant iodine nitrate adduct of 3, namely, benzyl 2-O-benzyl-3-deoxy-3-iodo-4-O-nitro-β-L-lyxopyranoside (4), is also described.

Synthesis and Antiviral Activity of 2‘-Deoxy-4‘-thio Purine Nucleosides

“…It was hoped that the slight change in the size and electronegativity of the ribose ring would lead to compounds that retained the activity of the 4‘-oxo analogues but had decreased toxicity and increased metabolic stability. Of the heteroatom-substituted sugars studied, the 4‘-thio class of nucleosides had the best biological profile. − Some of these early analogues had interesting antibiotic 5 and antineoplastic 6-9 activities, but these compounds were not developed further. Several 4‘-thio sugar variations were made, including d - ribo , d - arabino , d - xylo , d - erythro , and d - threo 3 nucleosides.…”

“…Of the heteroatom-substituted sugars studied, the 4′-thio class of nucleosides had the best biological profile. [1][2][3][4][5][6][7][8][9] Some of these early analogues had interesting antibiotic 5 and antineoplastic [6][7][8][9] activities, but these compounds were not developed further. Several 4′-thio sugar variations were made, including D-ribo, 1 D-arabino, 2 D-xylo, 2 D-erythro, 3 and D-threo 3 nucleosides.…”

Miriamin, a defensive diterpene from the eggs of a land slug ( Arion sp.)

“…3). The mixture of acetylated C 5 -alcohols was subjected to column chromatography, yielding pure samples of a mixture (about 1:1) of two diastereomeric 1,3,4-pentanetriol triacetates (3) and of a mixture of the diastereomeric 1,2,3,5-pentanetetrol tetraacetates (2). In addition, the fragment derived from the C-3 to C-6 portion of 1, 1,4-pentanediol diacetate (6), was isolated.…”

Synthesis and Biological Activity of Thionucleosides

“…Szarek and co-workers also reported a better synthetic method for 4'-thiocordycepin (37) starting from a benzyl protected compound 46 in place of a benzoyl protected compound 29 by the same synthetic procedure as described in Scheme 5 (Scheme 8). 12 For the study of biological activity, 1-(2-deoxy-4-thio-b-D-erythro-pentofuranosyl)-5-fluorouracil (57) was synthesized by condensation of 55 with the trimethylsilyl derivative of 5-fluorouracil catalyzed by mercuric oxide/ mercuric bromide. The reaction provided a favorable yield of the desired b-D-anomer 57, whereas use of stannic chloride as the catalyst gave primarily its a-anomer together with only a trace of 57 (Scheme 9).…”