A rapid access to hydroxylated benz[a]anthraquinones: Hypervalent iodine oxidation of β-naphthols
摘要:
Anionic annulation of phthalide sulfones 3 with quinone monoketals 6, accessible by phenyliodonium diacetate oxidation of naphthols 5, offers a high yielding regiospecific entry to benz[a]anthraquinones 8. Similar annulation of cyanophthalide 13 with 12, followed by photooxygenation of 14 results in a complementary route to the basic skeleton 15 of nonaromatic A-ring angucyclines. (C) 1997, Published by Elsevier Science Ltd.
Convergent and rapid assembly of benzonaphthopyranone cores of chartreusin, chrymutasins and hayumicins
作者:Dipakranjan Mal、Asit Patra、Haren Roy
DOI:10.1016/j.tetlet.2004.08.142
日期:2004.10
A new methodology for the rapid regiospecific synthesis of benzonaphthopyranones has been developed, on the basis of a tactical extension of the Hauser-Kraus annulation. The prowess of the methodology has been illustrated by a short synthesis of chartarin (22b) and a facile entry to the chrymutasin scaffold (26). (C) 2004 Elsevier Ltd. All rights reserved.