Neuraminidase (NA) cleaves the glycosidic bond linkages of sialic acids to release the mature virions from infected cells and has been an attractive therapeutic target for anti-influenza agents. In our ongoing investigation of NA inhibitors in mushroom extracts, we found that the extract the fruiting body of Glaziella splendens potently inhibited neuraminidase. The fruiting bodies of G. splendens were extracted and partitioned successively with hexane, ethyl acetate, and butanol. The ethyl acetate soluble-layer was subjected to silica gel and Sephadex LH-20 column chromatographies, and MPLC to obtain five compounds (1–5). Their structures were determined by spectroscopic methods. NA inhibitory activity of these compounds was evaluated using NAs from recombinant rvH1N1, H3N2, and H5N1 influenza A viruses. One compound (1) was elucidated as a new azaphilone derivative, and four compounds (2–5) were identified as entonaemin A, comazaphilone D, rubiginosin A, and entonaemin B, respectively. Compounds 3 and 4 showed considerable inhibitory activity against three types of neuraminidases with the IC₅₀ values of 30.9, 41.8, and 35.7 µM for 3 and 46.5, 50.4, and 29.9 µM for 4, respectively. This study reveals that the fruiting bodies of G. splendens possess azaphilone derivatives with the NA inhibitory activity. This is the first report on the isolation of neuraminidase inhibitors from the fruiting bodies of G. splendens.

神经氨酸酶（NA）可以裂解唾液酸的糖苷键，从而从感染的细胞中释放出成熟的病毒体，并且一直是抗流感药物的有吸引力的治疗靶标。在我们正在进行的对蘑菇提取物中NA抑制剂的研究中，我们发现提取物Glaziella splendens的子实体有效地抑制了神经氨酸酶。G的子实体。提取草，并依次用己烷，乙酸乙酯和丁醇分配。乙酸乙酯可溶层进行硅胶和Sephadex LH-20柱层析，并MPLC以获得五种化合物（1 - 5）。通过光谱法确定它们的结构。使用重组rvH1N1，H3N2和H5N1甲型流感病毒的NA评估这些化合物的NA抑制活性。一种化合物（1）中的溶液鉴定为一个新的azaphilone衍生物，和四种化合物（2 - 5）被确定为entonaemin A，comazaphilone d，rubiginosin A，和entonaemin B，分别。化合物3和4表现出相当的抑制活性对三种类型的神经氨酸酶的与IC ₅₀的值30.9，41.8，和35.7μM为3和46.5，50.4，29.9μM为4分别。这项研究表明G的子实体。一串红具有与NA抑制活性azaphilone衍生物。这是关于从G的子实体中分离神经氨酸酶抑制剂的首次报道。灿烂的。