Synthesis of Four Pentacyclic Triterpene–Sialylglycopeptide Conjugates and Their Affinity Assays with Hemagglutinin

Abstract

Influenza outbreaks pose a serious threat to human health. Hemagglutinin (HA) is an important target for influenza virus entry inhibitors. In this study, we synthesized four pentacyclic triterpene conjugates with a sialylglycopeptide scaffold through the Cu(I)-catalyzed alkyne-azide cycloaddition reaction (CuAAC) and prepared affinity assays of these conjugates with two HAs, namely H1N1 (A/WSN/1933) and H5N1 (A/Hong Kong/483/97), respectively. With a dissociation constant (KD) of 6.89 μM, SCT-Asn-betulinic acid exhibited the strongest affinity with the H1N1 protein. Furthermore, with a KD value of 9.10 μM, SCT-Asn-oleanolic acid exhibited the strongest affinity with the H5N1 protein. The conjugates considerably enhanced antiviral activity, which indicates that pentacyclic triterpenes can be used as a ligand to improve the anti-influenza ability of the sialylglycopeptide molecule by acting on the HA protein.

Phytocompounds as a source for the development of new drugs to treat respiratory viral infections

“…This potential was related to the ability of the multivalent system to bind the hemagglutinin protein, which prevents the interaction of this viral glycoprotein with the receptors of the host cell membrane and consequently inhibits the entry of the virus [ 141 ]. Similar results have also been observed for pentacyclic triterpenes conjugated to sialylglycopeptide [ 142 ].…”

An efficient UV-C device for decontaminating personal protective equipment (PPE) soiled with human Corona and Influenza virus: Solution for small-scale reuse

“…Our data indicate that 15 min UV-C exposure of the human H1N1 virus substantially reduces viral replication potential and limits the productive accumulation of infectious viral particles inside the cells. Given that the HA surface glycoprotein of the in uenza virus plays a critical role in viral entry and fusion to host cells, further, we claim that UV-C exposure to contaminated PPE for 15 min can ensure an absolute reduction in HA titer[49][50][51]. Finally, the data obtained from transcriptional analysis of the In uenza M gene segment indicates the potential of UV-C irradiation in limiting the intracellular accumulation of vRNA.…”