Qiu Chongyue, Yuan Ting, Sun Dejuan, Gao Suyu, Chen Lixia
Key Laboratory of Structure-Based Drug Design & Discovery, Department of Natural Products Chemistry, School of Traditional Chinese Materia Medica, Wuya College of Innovation, Ministry of Education, Shenyang Pharmaceutical University, Shenyang, 110016, China.
J Nat Med. 2017 Apr;71(2):449-456. doi: 10.1007/s11418-016-1068-z. Epub 2017 Jan 10.
Biotransformations of physapubescin (1) were performed by four fungal strains-Mucor subtilissimus AS 3.2454, Mucor polymorphosporus AS 3.3443, Aspergillus niger AS 3.795, and Syncephalastrum racemosum AS 3.264. Four metabolites were prepared in the biotransformation process of 1, and their structures were elucidated as 15α-acetoxy-5,6β:22,26:24,25-triepoxy-26α-hydroxy-3β-methoxy 4β-hydroxyergost-1-one (2), 15α-acetoxy-5,6β:22,26-diepoxy-4β,24β,25α,26(α, β)-tetrahydroxyergost-3β-methoxy-1-one (3a/3b), 15α-acetoxy-5,6β:22,26-diepoxy-4β,24β,25α,26(α, β)-tetrahydroxyergost-2-en-1-one (4a/4b), and physapubescin D (5), by spectroscopic data analysis. Among them, metabolites 2 and 3 are new. All of these fungal strains showed the ability to be highly stereo- and region-specific for the bioconversion of substrate (1). Our research provides a reference for the structural derivatization of withanolides or possibly even other natural products.
用四种真菌菌株——微小毛霉AS 3.2454、多孢毛霉AS 3.3443、黑曲霉AS 3.795和总状共头霉AS 3.264对类牛膝甾酮（1）进行生物转化。在1的生物转化过程中制备了四种代谢产物，通过光谱数据分析确定它们的结构分别为15α - 乙酰氧基 - 5,6β:22,26:24,25 - 三环氧 - 26α - 羟基 - 3β - 甲氧基 - 4β - 羟基麦角甾 - 1 - 酮（2）、15α - 乙酰氧基 - 5,6β:22,26 - 二环氧 - 4β,24β,25α,26(α,β) - 四羟基麦角甾 - 3β - 甲氧基 - 1 - 酮（3a/3b）、15α - 乙酰氧基 - 5,6β:22,26 - 二环氧 - 4β,24β,25α,26(α,β) - 四羟基麦角甾 - 2 - 烯 - 1 - 酮（4a/4b）和类牛膝甾酮D（5）。其中，代谢产物2和3是新的。所有这些真菌菌株对底物（1）的生物转化均表现出高度的立体和区域特异性。我们的研究为茄烷型内酯或甚至其他天然产物的结构衍生化提供了参考。
