De novo consecutive chemo/regioselective IBX mediated oxidation of andrographolide and its derivatives
作者:Sudhakar Mokenapelli、Madhu Gutam、Ramana Govu、Vijay Kumar Pasala、Jayaprakash Rao Yerrabelly、Prasad Rao Chitneni
DOI:10.1080/00397911.2019.1587775
日期:2019.5.19
Abstract A new IBX mediated protocol for regio/chemoselective oxidation of andrographolide (1), a labdane diterpenoid isolated from Andrographis paniculata, is developed. After the initial success of this protocol with andrographolide (1) to provide 19-dehydroandrographolide (5) or 3,19-didehydroandrographolide (6) as major products, the procedure was further applied for the oxidation of hydroxyl functionality
摘要 开发了一种新的 IBX 介导的穿心莲内酯 (1) 区域/化学选择性氧化方案,穿心莲内酯是一种从穿心莲中分离出来的劳丹烷二萜。该协议与穿心莲内酯 (1) 初步成功以提供 19-脱氢穿心莲内酯 (5) 或 3,19-二脱氢穿心莲内酯 (6) 作为主要产品后,该程序进一步应用于穿心莲内酯衍生物中羟基官能团的氧化,即 2 、3、14 和 16。该过程同样适用于毫克到克的范围内。在乙腈-水 (8:2) 系统中使用 TBDMS-Cl 以良好的收率实现了化合物 15 和 18 中 C-19-OTBDMS 的脱保护。图形概要