20-hydroxycholesterol is a signaling oxysterol with immunomodulating functions and, thus, structural analogues with reporter capabilities could be useful for studying and modulating the cellular processes concerned. We have synthesized three new 20-hydroxycholesterol-like pregn-5-en-3β-ol derivatives with fluorescent 7-nitrobenzofurazan (NBD) or Raman-sensitive alkyne labels in their side-chains. In silico computations demonstrated the compounds possess good membrane permeability and can bind within active sites of known 20-hydroxycholesterol targets (e.g. Smoothened and yeast Osh4) and some other sterol-binding proteins (human LXRβ and STARD1; yeast START-kins Lam4S2 and Lam2S2). Having found good predicted membrane permeability and binding to some yeast proteins, we tested the compounds on microorganisms. Fluorescent microscopy indicated the uptake of the steroids by both Saccharomyces cerevisiae and Yarrowia lipolytica, whereas only S. cerevisiae demonstrated conversion of the compounds into 3-O-acetates, likely because 3-O-acetyltransferase Atf2p is present only in its genome. The new compounds provide new options to study the uptake, intracellular distribution and metabolism of sterols in yeast cells as well as might be used as ligands for sterol-binding proteins.

中文翻译：

---

具有荧光NBD或炔烃标记的新型20-羟基胆固醇样化合物：合成，与蛋白质的计算机相互作用以及酵母细胞的摄取。

20-羟基胆固醇是具有免疫调节功能的信号性氧固醇，因此，具有报道分子功能的结构类似物可用于研究和调节相关的细胞过程。我们合成了三个新的20-羟基胆固醇样pregn-5-en-3β-ol衍生物，它们的侧链带有荧光7-硝基苯并呋喃山（NBD）或拉曼敏感的炔烃标记。在计算机运算中证明该化合物具有良好的膜通透性，并且可以在已知的20-羟基胆固醇靶标（例如，Smoothened和酵母Osh4）和一些其他固醇结合蛋白（人LXRβ和STARD1；酵母START-kins Lam4S2和Lam2S2）的活性位点内结合。发现良好的预测膜通透性并结合某些酵母蛋白后，我们在微生物上测试了这些化合物。荧光显微镜显示酿酒酵母和解脂耶氏酵母均吸收类固醇，而只有酿酒酵母显示出该化合物转化为3-O-乙酸盐，这可能是因为3-O-乙酰基转移酶Atf2p仅存在于其基因组中。这些新化合物为研究酵母细胞中固醇的摄取，细胞内分布和代谢提供了新的选择，并可用作固醇结合蛋白的配体。