Strategies for desymmetrising trehalose to synthesise trehalose glycolipids

Abstract

The desymmetrisation and regioselective protection of trehalose are major challenges in the chemical synthesis of biologically essential trehalose glycolipids. We reviewed the literature on desymmetrising trehalose to synthesise trehalose glycolipids and highlighted an efficient regioselective 6-O-phosphorylation method that can be applied to synthesise asymmetric trehalose glycolipids.

A β‐Diketiminato‐Based Pincer‐Type Nickel(II) Complex: Synthesis and Catalytic Performance in the Cross‐Coupling of Aryl Fluorides with Aryl Grignard Reagents

“…However, it remains difficult to activate aryl fluorides using pincer-type Ni catalysts. [56,57] We have recently reported the synthesis of -aminoketonato- [58] and -diketiminato-based tridentate pincer-type complexes of iron [59,60] and nickel. [61] In our ongoing study of Ni II complexes, we have prepared three different types of Ni II complexes, Ni-ONN, Ni-ONP, and Ni-NNN, and their catalytic performances have been investigated ( Figure 1).…”

Unusually Stable Picoloyl‐Protected Trimethylsilyl Glycosides for Nonsymmetrical 1,1′‐Glycosylation and Synthesis of 1,1′‐Disaccharides with Diverse Configurations

“…[19,20] Alternatively, these disaccharides can be acquired by coupling of glycosyl donors with glycosyl acceptors through so called 1,1'-glycosylation. [19,20] Alternatively, these disaccharides can be acquired by coupling of glycosyl donors with glycosyl acceptors through so called 1,1'-glycosylation.…”

“…Although nonsymmetrical 1,1'-disaccharides can be constructed by desymmetrizing 1,1'-disaccharides ubstrates, this approachi sl imited by substrate availability. [19,20] Alternatively, these disaccharides can be acquired by coupling of glycosyl donors with glycosyl acceptors through so called 1,1'-glycosylation. [2,[21][22][23] However the 1,1'-glycosylationi nvokes two anomeric centersa nd may produceu pt of our diastereomers.…”

Alkylamino‐Directed One‐Pot Reaction of N‐Alkyl Anilines with CO, Amines and Aldehydes Leading to 2,3‐Dihydroquinazolin‐4(1H)‐ones

“…Among the established synthetic protocols, the typical procedures involve cyclocondensation of o-amino-benzamides (usually obtained by ammonolysis of isatoic anhydride) with aldehydes (Scheme 1a), [3a,22] reductive cyclization of onitrobenzamides or o-azidobenzamides with carbonyl compounds (Scheme 1b), [23] cyclocondensation of isatoic anhydrides, primary amines (or ammonium salts) and aldehydes (Scheme 1c), [2b,5a,22a,24] and cyclocondensation of o-aminobenzonitriles with carbonyl compounds (Scheme 1d). [25] Despite the above advances, however, one major drawback associated with all the above approaches is that the N 1 -containing starting materials applied in these protocols are usually Figure 1. Representative examples of clinically significant DHQA medications.…”

“…Among the established synthetic protocols, the typical procedures involve cyclocondensation of o-amino-benzamides (usually obtained by ammonolysis of isatoic anhydride) with aldehydes (Scheme 1a), [3a,22] reductive cyclization of onitrobenzamides or o-azidobenzamides with carbonyl compounds (Scheme 1b), [23] cyclocondensation of isatoic anhydrides, primary amines (or ammonium salts) and aldehydes (Scheme 1c), [2b,5a,22a,24] and cyclocondensation of o-aminobenzonitriles with carbonyl compounds (Scheme 1d). [25] Despite the above advances, however, one major drawback associated with all the above approaches is that the N 1 -containing starting materials applied in these protocols are usually 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 complex, costly, and lack structural diversity. In addition, these synthetic strategies also suffer from certain limitations such as harsh reaction conditions, lengthy steps, tedious procedures for preparation of catalysts and tedious work-up conditions.…”