The cyclization mechanism of squalene in hopene biosynthesis: the terminal methyl groups are critical to the correct folding of this substrate both for the formation of the five-membered E-ring and for the initiation of the polycyclization reaction

被引：28

作者：

Hoshino, T ^{[1
]}

Kondo, T

机构：

[1] Niigata Univ, Fac Agr, Dept Appl Biol Chem, Niigata 9502181, Japan

[2] Niigata Univ, Grad Sch Sci & Technol, Niigata 9502181, Japan

来源：

CHEMICAL COMMUNICATIONS | 1999年 / 08期

关键词：

D O I：

10.1039/a901351b

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Incubations of C(23)-norsqualenes 5 and 6, lacking one of the two terminal methyl groups, with squalene-hopene cyclase gave unprecedented products 7 and 8 having a tetrahymanol skeleton together with a neohopane skeleton 12, strongly suggesting that the two geminal methyls of squalene 1 are critical to the formation of the five-membered E-ring in hopene biosynthesis and also are required to initiate the cyclization reactions of 1 into the pentacyclic triterpenes 2 and 3.

引用

页码：731 / 732

页数：2

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