Culture feeding experiments with [1-¹³C]-acetate, [2-¹³C]- acetate, and [1,2-¹³C]-acetate have shown that the steroid ring B contraction involved in the biogenesis of the unprecedented carbon skeleton of the antibiotic solanioic acid (1) by the fungus Rhizoctonia solani involves cleavage of the C-5/C-6 bond. The study revealed that 9-epi-solanioic acid (4), which spontaneously converts to solanioic acid (1), is also produced by the cultures and it may be the actual natural product.

中文翻译：

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稳定的同位素喂养研究表明，由真菌Rhozoctonia solani产生的抗生素茄酸类固醇5（6→7）的beoo环收缩生物发生

培养喂养实验用[1- ¹³ C] -乙酸甲酯，[2- ¹³ C] -乙酸盐，和[1,2 ¹³ C] -乙酸盐已经表明参与前所未有碳骨架的生物合成类固醇环B收缩茄根真菌Rhozoctonia solani对抗生素茄酸（1）的裂解涉及C-5 / C-6键的裂解。该研究表明，培养物也可自发转化为茄酸（9）的9-表-茄酸（4），它可能是实际的天然产物。