analogues of calbistrins, okaramines and secalonicacids were detected. All novel compounds were tested for antifungal activity against Candida albicans, however all showed only weak or no activity. Aspergillusaculeatus IBT 21030 was additionally shown to be capable of producing sclerotia. Examination of the sclerotia revealed a highly regulated production of metabolites in these morphological structures
3-6, together with the known secalonicacidD (7), were isolated from a fermentation culture of the fungus Aspergillusaculeatus. Their structures and absolute configurations were established by analyses of their spectroscopic data, including 1D and 2D-NMR spectra, HR-ESIMS, electronic circular dichroism (ECD) data, and quantum chemical calculations. These metabolites were evaluated for in vitro cytotoxic
六个倍半萜类化合物1-6,包括两个新的,一种ent-daucane型倍半萜类化合物,曲霉A(1)和一个正癸烷一个,asperaculane B(2),以及四个已知的降丁烷衍生物,aculenes AD 3-6,以及从真菌曲霉曲霉的发酵培养物中分离出已知的乙二醛酸D(7)。通过分析其光谱数据,包括1D和2D-NMR光谱,HR-ESIMS,电子圆二色性(ECD)数据以及量子化学计算,可以确定它们的结构和绝对构型。评估了这些代谢物对两种细胞系,人癌细胞系(HeLa)和一种正常仓鼠细胞系(CHO)的体外细胞毒活性。
The first synthesis of aculenes B and D was accomplished in 14 and 16 steps, respectively, from a known hydroxy carboxylic acid by employing a diastereoselective Barbier reaction as the key step. Reversal of the stereoselectivity was observed between the Barbier reaction of a β-keto-aldehyde intermediate and that of its acetal-protected congener.
Aculenes B 和 D 的首次合成分别经过 14 步和 16 步,从已知的羟基羧酸开始,采用非对映选择性 Barbier 反应作为关键步骤。在 β-酮醛中间体与其缩醛保护的同类物的 Barbier 反应之间观察到立体选择性的逆转。