Haldar Saikat, Mulani Fayaj A, Aarthy Thiagarayaselvam, Thulasiram Hirekodathakallu V
†Chemical Biology Unit, Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune-411008, India.
§CSIR-Institute of Genomics and Integrative Biology, Mall Road, New Delhi-110007, India.
J Org Chem. 2015 Jun 19;80(12):6490-5. doi: 10.1021/acs.joc.5b00417. Epub 2015 May 29.
Regio- and stereoselective 11β-hydroxylation was achieved on the basic limonoid skeleton through microbial transformation. Whole cells of Cunninghamella echinulata efficiently converted basic limonoids such as epoxyazadiradione, azadiradione, and gedunin to their 11β-hydroxy analogues as the sole metabolite. Fermentation conditions affecting the efficiency (96%) of biotransformation including substrate concentration, incubation period, pH, and temperature were optimized. The position and stereochemistry of hydroxyl functionality on the isolated metabolites were established through extensive spectroscopic and spectrometric studies (1D, 2D NMR, ESI-MS, and MS/MS).
通过微生物转化在基本柠檬苦素骨架上实现了区域和立体选择性11β-羟基化。刺孢小克银汉霉的全细胞能有效地将环氧印苦楝子素、印苦楝子素和格杜宁等基本柠檬苦素转化为其11β-羟基类似物作为唯一代谢产物。对影响生物转化效率（96%）的发酵条件进行了优化，包括底物浓度、培养时间、pH值和温度。通过广泛的光谱和光谱分析研究（一维、二维核磁共振、电喷雾电离质谱和串联质谱）确定了分离代谢产物上羟基官能团的位置和立体化学。
