New synthesis of heteroglycoclusters from p-t-butylcalix[4]arene tetraalkoxyheterohalides as key intermediates

Abstract

A straightforward synthesis of heteroglycoclusters based p-t-butylcalix [4]arene has been achieved. The key step is the formation of hetero-halopentyloxy-p-t-butylcalix [4]arene mixture via haloalkylation with 1-bromo-5-chloropentane as asymmetric alkylating reagent. Subsequent selective exchange of bromide by azide under mild conditions provides selectively azido-chloro species suitable for click reaction with first propargylglycoside. The products here can then be subjected to further azidation to enable attachment of different glycosides via click chemistry reaction.

Unprecedented Thiacalixarene Fucoclusters as Strong Inhibitors of Ebola cis-Cell Infection and HCMV-gB Glycoprotein/DC-SIGN C-type Lectin Interaction

“…The cluster 2, which derived from this, was easily obtained at a yield of 54% after C18-reverse-phase chromatography with an To evaluate the topological impact on DC-SIGN inhibition, we subsequently synthesized p-tBu-calix [4]arene fucocluster 3 using the same strategy (Scheme 2). We started with the wellknown cone conformation of tetraazido-propyloxy-p-tBucalix [4]arene 13 53 and the click chemistry reaction with Ugiadduct 7. We obtained tetrabromoalkyl-pseudopolypeptide 14 Here we report the examination of the recognition behavior of ligands 1, 2, and 3, as well as the efficiency of the scaffold, for the inhibition of the extracellular domain (ECD) of DC-SIGN binding using a SPR competition assay.…”

Cu(I)-Catalyzed Click Chemistry in Glycoscience and Their Diverse Applications

“…Interestingly, Lesur and co-workers reported a practical and simple route for easy access to calix[4]­arene heteroglycoclusters combining mannose and fucose residues via a Finkelstein halide exchange process as the key step …”

Heteroglycoclusters through Unprecedented Orthogonal Chemistry Based on N‐Alkylation of N‐Acylhydrazone

“…[19] The third uses suitably orthogonally functionalized scaffolds sequentially crosslinked to various sugars in a controlled manner. [20][21][22] Although it remains a challenging problem to overcome, this orthogonal strategy based on sequential chemo-selective reactions remains an approach [23] that provides a relevant solution to design complex molecules for a wide range of applications. [23][24][25] It is particularly appropriate in the context of biologically active molecules as heteroglycolcusters.…”

“…The second employs orthogonally protected building blocks and sequential deprotection/conjugation with different sugars [19] . The third uses suitably orthogonally functionalized scaffolds sequentially crosslinked to various sugars in a controlled manner [20–22] . Although it remains a challenging problem to overcome, this orthogonal strategy based on sequential chemo‐selective reactions remains an approach [23] that provides a relevant solution to design complex molecules for a wide range of applications [23–25] .…”