125731-00-2Relevant academic research and scientific papers
Fully Regiocontrolled Synthesis of (+/-)-12a,12b-Secocolchicine and Studies Concerning its Cyclisation to the Alkaloid Colchicine
Banwell, Martin G.,Lambert, John N.,Gravatt, G. Lance
, p. 2817 - 2830 (2007/10/02)
A fully regiocontrolled synthesis of the title compound 6, an AC-ring analogue of the alkaloid colchicine 1, is reported.The key step associated with the sequence used was condensation of lithium halogenocarbenoid 10 - a synthetic equivalent for the inaccessible 7-methoxytropon-3-yl anion 12-with 3,4,5-trimethoxycinnamaldehyde 17 to produce the 1,2-addition product 18 as a mixture of diastereoisomers.Elaboration of compound 18 provided benzoate 23 which, on treatment with base, underwent ring-expansion to give troponoid 24 in excellent yield.Replacement of the C-7 benzoate group in compound 24 by an acetamido moiety was readily achieved and produced compound 6 in good overall yield.Unsuccessful attempts to convert compound 6 and the deacetamido analogue 38 into colchinine and deacetamidocolchicine 3, respectively, are described.
The Development of a Fully Regiocontrolled Synthesis of (+/-)-12a,12b-Monosecocolchicine using a Synthetic Equivalent for the 7-Methoxy-3-troponyl Anion
Banwell, Martin G.,Gravatt, G. Lance,Buckleton, John S.,Clark, George R.,Ricard, C. E. F.
, p. 865 - 867 (2007/10/02)
The lithio-species (6) acts as a synthetic equivalent for the 7-methoxy-3-troponyl anion (3) and has been employed in a fully regiocontrolled synthesis of the title compound (2).
