✍ Scribed by Vinko Škarié; Jasenka Matulié-Adamié
No coin nor oath required. For personal study only.
The stereospecific cis‐hydroxylation of 1‐(2,3‐dideoxy‐β‐D‐glyceropent‐2‐enofuranosyl)thymine (1) into 1‐β‐D‐ribofuranosylthymine (2) by osmium tetroxide is described. Treatment of 2′,3′‐O, O‐isopropylidene‐5‐methyl‐2,5′‐anhydrouridine (8) with hydrogen sulfide or methanolic ammonia afforded 5′‐deoxy‐2′,3′‐O, O‐isopropylidene‐5′‐mercapto‐5‐methyluridine (9) and 2′,3′‐O, O‐isopropylidene‐5‐methyl‐isocytidine (10), respectively. The action of ethanolic potassium hydroxide on 5′‐deoxy‐5′‐iodo‐2′,3′‐O, O‐isopropylidene‐5‐methyluridine (7) gave rise to the corresponding 1‐(5‐deoxy‐β‐D‐erythropent‐4‐enofuranosyl)5‐methyluracil (13) and 2‐O‐ethyl‐5‐methyluridine (14).
The hydrogenation of 2 and its 2′,3′‐O, O‐isopropylidene derivative 4 over 5% Rh/Al~2~O~3~ as catalyst generated diastereoisomers of the corresponding 5‐methyl‐5,6‐dihydrouridine (17 and 18).
📜 SIMILAR VOLUMES
A short, efficient synthesis of 5%-amino-5%-(S)-methyl-2%,5%-dideoxynucleosides 1 has been developed through the diastereoselective addition of methylmagnesium bromide or methyllithium to an intermediate tert-butylsulfinimide.