Nidulal (1), a novel inducer of differentiation of human HL-60 promyelocytic leukemia cells, was isolated from fermentations of the basidiomycete Nidula candida together with low amounts of niduloic acid (2). Both compounds are bisabolane sesquiterpenes. Their structures were elucidated by spectroscopic methods. In reporter gene assays nidulal (1) preferentially activated the transcription factor complex AP-1-mediated expression of secreted alkaline phosphatase in COS-7 cells. In addition nidulal (1) and niduloic acid (2) exhibited weak cytotoxic and antibiotic activities.

中文翻译：

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Nidulal，一种从念珠菌中分化出人类早幼粒细胞白血病细胞的新型诱导剂。

Nidulal（1）是人HL-60早幼粒细胞白血病细胞分化的新型诱导剂，是从念珠菌Nidula candida的发酵以及少量的Niduloic acid（2）中分离出来的。两种化合物都是双五倍烷倍半萜。通过光谱法阐明了它们的结构。在记者基因检测中，nidulal（1）优先激活转录因子复合物AP-1介导的COS-7细胞中分泌的碱性磷酸酶的表达。此外，腈醛（1）和己二酸（2）表现出较弱的细胞毒性和抗生素活性。