Synthesis of the Integrastatin Nucleus Using the Ramberg−Bäcklund Reaction
摘要:
The first synthesis of the tetracyclic nucleus of the Integrastatins, natural products that have been shown to selectively inhibit HIV-1 integrase, is reported. Key steps of this synthesis involve a novel cis-selective Ramberg-Backlund reaction and an unusual Lewis acid-promoted cyclization step.
Tin(II) chloride dihydrate-mediated deacetalisation- bicyclisation procedures for the construction of novel polycyclic heterocycles from amides possessing a pendant acetal group are re- ported. Optimisation and scoping studies are described; using this methodology, a range of known, and novel, ring-fused heterocyclic systems have been prepared, some in enantiomerically pure form.
Synthesis of the Integrastatin Nucleus Using the Ramberg−Bäcklund Reaction
作者:Jonathan S. Foot、Gerard M. P. Giblin、Richard J. K. Taylor
DOI:10.1021/ol035786v
日期:2003.11.1
The first synthesis of the tetracyclic nucleus of the Integrastatins, natural products that have been shown to selectively inhibit HIV-1 integrase, is reported. Key steps of this synthesis involve a novel cis-selective Ramberg-Backlund reaction and an unusual Lewis acid-promoted cyclization step.
Improved and Practical Synthesis of the Integrastatin Core
The new and versatile method for the synthesis of integrastatin core has been developed by the use of o-toluic acid and 2′-hydroxyacetophenone with NaH/sec-BuLi, followed by the reaction of dihydroisocoumarins with MeLi. The overall steps for the synthesis of integrastatin core was only 3 steps including the known method by the literature. The scope and limitations of substrates bearing the various substituents on the aromatic ring were investigated. The chemical yields by our approach are generally high and the current route enables us the rapid synthesis.