A tandem radical macrocyclisation-transannular cyclisation approach towards the taxanes

被引：29

作者：

Hitchcock, SA ^{[1
]}

Houldsworth, SJ ^{[1
]}

Pattenden, G ^{[1
]}

Pryde, DC ^{[1
]}

Thomson, NM ^{[1
]}

Blake, AJ ^{[1
]}

机构：

[1] Univ Nottingham, Sch Chem, Nottingham NG7 2RD, England

来源：

JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1 | 1998年 / 19期

关键词：

D O I：

10.1039/a805268i

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Separate treatment of the iodotrienedione 19 and the iododienynedione 38 with Bu3SnH-AIBN produces the corresponding taxane ring systems 25 (25-30%) and 56 (50-60%) respectively by way of tandem radical macrocyclisation-radical transannular cyclisations. By contrast the analogous iodopolyenones 61, 63, 65a, 66a, 86a and 87a, together with the corresponding iodoenynones 39a and 59 failed to undergo similar tandem radical reactions, and instead gave products resulting from direct reduction of the carbon-iodine bonds in these substrates. The structures of the taxane analogues 25 and 56 followed from analysis of their NMR spectroscopic data and comparison with similar NMR data for related taxoids described in the literature. The stereochemistry of 56 was secured from an X-ray crystal structure determination of the 1,5-diol 57 produced from reduction of 56 with DIBAL.

引用

页码：3181 / 3206

页数：26

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