Total Synthesis of Bryostatins: The Development of Methodology for the Atom-Economic and Stereoselective Synthesis of the Ring C Subunit
作者:Barry M. Trost、Alison J. Frontier、Oliver R. Thiel、Hanbiao Yang、Guangbin Dong
DOI:10.1002/chem.201002898
日期:2011.8.22
for the stereoselective assembly of the ring C subunit were developed. A Pd‐catalyzed tandem alkyne–alkyne coupling/6‐endo‐dig cyclization sequence was explored and successfully pursued in the synthesis of a dihydropyran ring system. Elaboration of this methodology ultimately led to a concise synthesis of the ring C subunit of bryostatins.
苔藓抑素是一个结构复杂的大环内酯类,表现出异常广泛的生物活性。这些分子的有限可用性和结构复杂性使得开发有效的全合成尤为重要。本文描述了我们对苔藓抑素全合成的初步努力,其中开发了用于环 C 亚基立体选择性组装的化学选择性和原子经济方法。在二氢吡喃环系统的合成中探索并成功地探索了Pd 催化的串联炔 - 炔偶联/6- endo - dig环化序列。这种方法的详细说明最终导致了苔藓抑素环 C 亚基的简明合成。
Synthetic studies on bryostatins, potent antineoplastic agents: Synthesis of the C17C27 fragment of C20 oxygenated bryostatins
作者:Ken Ohmori、Shigeru Nishiyama、Shosuke Yamamura
DOI:10.1016/0040-4039(95)01310-e
日期:1995.9
Synthetic process towards the bottom half portion of C20 oxygenated series of bryostatins is described. The stereogenic center at C20 position was constructed through a hydroxyl group-directed epoxidation by using mCPBA. It was found that silver (I) salt is an effective and mild reagent for regioselective ring cleavage of α-bromoepoxides into the corresponding α-hydroxyketones via oxonium ion intermediates