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Intramolecular Cyclization During Bromination of the Quinoline Alkaloid Haplophyllidine
A U Ubaidullaev1, V I Vinogradova1, Sh N Zhurakulov1,2
1S. Yu. Yunusov Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, Uzbekistan.
Abstract:
Bromination of the furanoquinoline alkaloid haplophyllidine by molecular bromine and N-bromosuccinimide was accompanied by intramolecular cyclization to form mixtures of new compounds containing additional penta-, hexa-, and spirocyclic rings incorporating the prenyl group of haplophyllidine. The structures and absolute configurations of the chiral centers of all four bromo-derivatives were elucidated using a combination of NMR spectroscopic methods and X-ray crystal structure analyses.
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