155051-97-1Relevant articles and documents
Synthesis from Thebaine of 10-Oxothebaine, Potentially a Precursor for κ-Selective Opiates
Henderson, Calum F.,Kirby, Gordon W.,Edmiston, John
, p. 295 - 298 (2007/10/02)
Thebaine 3 has been converted in an improved yield (72percent), with tetranitromethane, oxygen and ammonia, into the 14β-nitro 8α,10α-epidioxide 4, which reacted with base to give the known 14β-nitro-10-oxo compound 7.Reduction of this nitro compound with tributyltin hydride gave the 8β-hydroxy-10-oxodihydrothebaine 8, which was dehydrated with phosphorus oxychloride to give 10-oxothebaine 9.As expected, this conjugated diene reacted with but-3-en-2-one to form a Diels-Alder cycloadduct 10, the 10-oxo dirivative of thevinone 11, the precursor of a well known series of opiate analgesics.Unexpectedly, the epidioxide 4 was found to isomerise cleanly on activated alumina to give the 8α,10α-epoxy acetal 5, in which a peroxide oxygen has been inserted into the 7,8-bond of the bridged peroxide 4.