Synthesis of C4‐Acyl‐tetrofuranosides and C5‐Acyl‐pentopyranosides Enabled by the Liebeskind‐Srogl Cross‐Coupling Reaction

Abstract

An efficient and versatile protocol for the synthesis of C4‐acyl‐tetrofuranosides and C5‐acyl‐pentopyranosides has been established via the Liebeskind‐Srogl cross‐coupling reaction of various uronic acid‐derived thioesters and a wide range of arylboronic acids. Distinctive features of this transformation include mild reaction conditions, broad substrate scopes, impressive compatibility with a wide array of functional groups, and retention of stereochemical configurations. Dapagliflozin‐derived thioester is also amenable to this transformation, demonstrating the potential of this strategy in the late‐stage modifications of the active pharmaceuticals.

Access to 6-Deoxy-heptose Constructs by One Carbon Homologation of Hexoses with Malononitrile: Divergent Synthesis of Campylobacter jejuni Strain 81-176 Capsular Trisaccharide Repeating Unit Derivatives

“…To highlight the potential of sugar-based α-substituted propanedinitriles in the diversity-oriented synthesis of 6dHep p derivatives, compound 2f was exposed to oxidative transformations through the intermediacy of acyl cyanide. − As shown in Scheme , treatment of 2f with N -, O -, and S -nucleophiles under 1 atm of dioxygen atmosphere and 3.0 equiv of Cs 2 CO 3 in MeCN supplied the desired amides 4a – c , esters 4d – f , and thioesters 4g and 4h in 40–93% yields. Access to 4b and 4g provides an attractive avenue to sugar-derived ketones relying on either nucleophilic addition of organomagnesium and organolithium reagents to Weinreb’s amides or Liebeskind–Srogl cross-coupling reaction of arylthio esters with aryl boronic acids.…”

Pd-Catalyzed Stereospecific Glycosyl Cross-Coupling of Reversed Anomeric Stannanes for Modular Synthesis of Nonclassical C-Glycosides

“…Despite the attractive biological properties of nonclassical aryl C -glycosides, their synthesis has received limited attention. Compared to the rapid and well-studied synthesis of classical C -glycosides, ,,− the synthesis of nonclassical C -glycosides lags behind and poses several challenges, − impeding the development of more biomedically valuable sugar-based drugs. Traditional methods for synthesizing nonclassical aryl C -glycosides include the ZnBr 2 -mediated syn-selective addition reaction of aryl-zinc reagents to 4α-epoxypyranosides, and the selective [4 + 2] cycloaddition between aromatic aldehydes 7 and Danishefsky’s dienes 8 , yielding glycal derivatives 9 − (Figure B).…”