Synthesis of Novel N-carbohydrate-derived Heterocyclic Compounds by Nucleophilic Substitution Reaction of Carbohydrate Imidazole-1-sulfonates

Total Synthesis of Two Pyrrole Spiroketal Alkaloids: Pollenopyrroside A and Capparisine B

“…9 According to previous reports, 10 bishydroxymethylation of pyrrole was so slow that the reaction required approximately two weeks. In our study, microwave-assisted synthesis was applied to accelerate the bishydroxymethylation reaction, and the reaction time was shortened to 2-3 hours.…”

Synthesis and reactivity of imidazole-1-sulfonate esters (imidazylates) in substitution, elimination, and metal-catalyzed cross-coupling reactions: a review

“…It is interesting to note that when the reaction was carried out in toluene or THF under reflux, no desired product was observed. [17] …”

“…of NaH at 120°C, it was observed that the imidazylates of secondary alcohols favor β-elimination by an anti-elimination process even at room temperature (Scheme 11), while the imidazylates of primary alcohols are more likely to favor the S N 2 displacement reaction (Scheme 10). [17] …”

“…[11] These methods have been often cited as efficient protocols for the synthesis of imidazylates. [15][16][17][18][19][20] In the first two methods, (A and B), alkoxides are generated from 2 by either treatment with sodium hydride or via silyl ether 5 and underwent reaction with an Journal of Sulfur Chemistry 3 Scheme 1. Synthesis of alkyl imidazylates 6 from alcohols 2. excess of commercially available 1,1 -sulfonyldiimidazole (Im 2 SO 2 ) 4, [12,21] to give the corresponding alkyl imidazoylates 6 in good to high yields.…”

Aryl Sulfonates in Inversions at Secondary Carbohydrate Hydroxyl Groups: A New and Improved Route Toward 3-Azido-3-deoxy-β-d-galactopyranosides

“…Imidazylates and tosylates are more stable and have been known to act, in a few cases, as leaving group in inversion reactions on secondary carbohydrate hydroxyls. [6][7][8] By replacing triflates with less reactive sulfonates as leaving groups at C3 of 4,6-O-benzylidene galacto-and gulopyranosides, a scalable and more robust synthetic route towards 3-azido-3-deoxy-β-D-galactopyranosides was…”