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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 (K_D) of 6.89 ?M, SCT-Asn-betulinic acid exhibited the strongest affinity with the H1N1 protein. Furthermore, with a K_D value of 9.10 ?M, 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.

SUBMITTER: Luo M

PROVIDER: S-EPMC7915185 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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

Luo Mei M Wu Ximin X Li Yiming Y Guo Fujiang F

Molecules (Basel, Switzerland) 20210208 4

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) ...[more]

PMID: 33567740

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