RESUMO
Algae-based marine carbohydrate drugs are typically decorated with negative ion groups such as carboxylate and sulfate groups. However, the precise synthesis of highly sulfated alginates is challenging, thus impeding their structure-activity relationship studies. Herein we achieve a microwave-assisted synthesis of a range of highly sulfated mannuronate glycans with up to 17 sulfation sites by overcoming the incomplete sulfation due to the electrostatic repulsion of crowded polyanionic groups. Although the partially sulfated tetrasaccharide had the highest affinity for the receptor binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant, the fully sulfated octasaccharide showed the most potent interference with the binding of the RBD to angiotensin-converting enzyme 2 (ACE2) and Vero E6 cells, indicating that the sulfated oligosaccharides might inhibit the RBD binding to ACE2 in a length-dependent manner.
Assuntos
Enzima de Conversão de Angiotensina 2 , Antivirais , Micro-Ondas , Polissacarídeos , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/síntese química , Antivirais/química , Chlorocebus aethiops , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/química , Células Vero , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/síntese química , Humanos , Animais , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Ácidos Hexurônicos/síntese química , Sulfatos/química , Sulfatos/farmacologia , Sulfatos/síntese química , Tratamento Farmacológico da COVID-19 , Relação Estrutura-AtividadeRESUMO
Nucleoside analogues are widely used as anticancer and antiviral drugs. Here, we develop a highly efficient gold(I)-catalyzed N-glycosylation approach for versatile synthesis of various types of nucleosides and deoxynucleosides with glycosyl (Z)-ynenoates as donors. The wide scope of the N-glycosylation approach was demonstrated by the synthesis of 31 pyrimidine nucleosides and 8 purine nucleosides. Remarkably, the gold(I)-catalyzed N-glycosylation of pyranosyl (Z)-ynenoates with purines was found to be very effective for regioselective synthesis of pyranosyl N9 purine nucleosides. Based on the catalytic N-glycosylation approach, convenient synthesis of two 5'-deoxynucleosides drugs (capecitabine and galocitabine), four 2'-deoxynucleoside drugs (floxuridine, trifluridine, decitabine and cladribine), four 3',5'-dideoxynucleoside analogues, and four 2',5'-dideoxynucleoside analogues was achieved in a collective manner.