Cyclic phosphonomethylphosphinates: a new type of phosphorus-containing sugars
摘要:
The first synthesis of arabino-configured cyclic phosphonomethylphosphinates is described. The key step is the condensation of the triethylester of H-phosphinylphosphonate 10 on an hydroxyaldehyde 11 derived from a D-arabinal derivative followed by a cyclization induced under acetylation conditions. (C) 2003 Elsevier Science Ltd. All rights reserved.
A New Method for the Synthesis of Fluoro-Carbohydrates and Glycosides Using Selectfluor
作者:Michael D. Burkart、Zhiyuan Zhang、Shang-Cheng Hung、Chi-Huey Wong
DOI:10.1021/ja9723904
日期:1997.12.1
This paper describes a high-yield, one-step synthesis of 2-deoxy-2-fluoro sugars and their glycosides from glycals using the available electrophilic fluorination reagent 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Selectfluor) in the presence of a nucleophile. The method was further expanded to the synthesis of glycosyl fluorides and glycosides from anomeric hydroxy
tetrahydrofuran derivatives is reported from S-alkyl dithiocarbonates. The study of the group transfer reaction fromxanthates and alkenes afforded intermediate S-alkyl dithiocarbonates. From 2,3-dihydrofuran derivatives, the displacement of the resulting anomeric xanthates with various nucleophiles in the presence of Lewis acid allowed the formation of new carbon−carbon and carbon−heteroatom bonds
Iodosobenzene diacetate-Iodine and IBX-Iodine: Reagent systems for the synthesis of diastereomerically enriched 2-deoxy-2-iodoglycosyl acetates and 2-deoxy-2-iodoglycosyl ortho-iodobenzoates from protected glycals
作者:Puli Saidhareddy、Sama Ajay、Arun K. Shaw
DOI:10.1016/j.tet.2017.06.001
日期:2017.7
stereoselective synthesis of trans-2-deoxy-2-iodoglycosylacetates and O-iodobenzoates respectively from differently protectedglycals have been developed. They are compatible with a variety of protecting groups and various functional groups at 2C-position. Hexose-3,2-enolone 8 is obtained directly from 2-acetoxy glycal 5 by method A. An application to modified method B has been shown by synthesis of a diastereomerically
The synthesis of 3’-deoxy-3’-difluoromethyluridine (9) and 2’-deoxy-2’-difluoromethyluridine (7β) by hydrogenation of the corresponding difluoromethylene derivatives is described. A second synthesis of the latter has been performed. Starting from thymidine, a two-step procedure affords the benzylated furanoid glycal 12. Addition of dibromodifluoromethane gives the α-2’-deoxy-2’-bromodifluoromethylarabinose (13). This compound allowed an access to α- or β -2’-deoxy-2’-difluoromethyluridine via a SN2 type reaction on a α-halodeoxyarabinose species.