Combining Clays and Ultrasound Irradiation for an O-Acetylation Reaction of N-Glucopyranosyl and Other Molecules

Abstract

A convenient, efficient and fast acetylation combining clays and ultrasound irradiation is described. Some molecules from nature or synthetic source, i.e., D-glucose, glycerol, D-mannitol and 1,2,3-triazolic derivatives such as N-glucosyl sugars and 2-substituted 1,4-naphthoquinone structures were acetylated. This kind of chemistry may be classified as eco-friendly because the reactions take a short time and the catalyst is reusable.

Structure-Based Identification of Naphthoquinones and Derivatives as Novel Inhibitors of Main Protease Mpro and Papain-like Protease PLpro of SARS-CoV-2

“…We studied compounds with aromatic and aliphatic substituents, 60 , 70 , 79 − 85 the presence of selenium, 63 , 86 BODIPY, 87 , 88 and sugars, 70 among other substituent groups in the present quinoid structure. 44 , 89 − 92 …”

Uma acetilação eficiente e econômica do 1,2:3,4-di-O-isopropilideno-α-D-galactopiranose utilizando anidrido acético ativado in situ pela argila montmorilonita K10

“…4. Deste modo, a montmorilonita K10 ativou in situ o anidrido acético possibilitando uma maior deslocalização de carga tornando o carbono carbonílico mais eletrofílico, logo suscetível ao ataque nucleofílico do grupo hidroxila do composto 2 [42].…”

Design and Synthesis of Triazole-Phthalimide Hybrids with Anti-inflammatory Activity

“…The acetylene 1 was prepared according to the procedure described in the literature, as well as the 1 H-and 13 C-NMR data were in agreement with the literature. 8) Synthesis of N-(Azidoalkyl)phthalimide (2a-d) The azide compounds 2a-d were prepared according to the proce-dure described in the literature. 27) The 1 H-and 13 C-NMR are in accordance with previously reported data.…”

“…7) For instance, our research reported an intramolecular CH-O hydrogen bond between H 5 -triazolic and the endocyclic oxygen of N-glucopyranoside. 8) In addition, an assisted version of a classical E2 elimination mechanism to furnish conjugated alkene after triazole protonation was described by de Oliveira et al 9) Since the discovery of click chemistry by Fokin and Sharpless, 10) and Tornøe and Meldal,11) reactions involving copper-catalyzed azide-alkyne cycloaddition (CuAAC) have gained popularity as a general strategy for the synthesis of 1,4-disubstituted 1,2,3-triazoles. Recently, several of these compounds have been prepared employing the click chemistry protocol 12,13) providing rapid access to small molecules as privileged medicinal scaffolds.…”