Deaminocolchinol methyl ether

These results the authors consider cannot be aeeounted for on the basis of a 6-membered ring B and the adoption of a 5- or 7-membered ring B introduces a difficulty in explaining the formation of 2 3 4 7-tetramethoxyphenanthraquinone in the oxidation of deaminocolchinol methyl ether. There is, however, a precedent in Weitzenbock s oxidation of 4 5 6 7-dibenzo-d -c /cZoheptatriene-l-aldehyde (X) to phenanthraquinone, for representing the a -unsaturated ketone as 9 12 13 14-tetramethoxy-3 4 5 6-dibenz-d -c /cZoheptatriene-7-one (XI CH2 at —> CO), using the system of numbering adopted by... 

These results indicate that deaminocolchinol methyl ether is 9 2 13 14-tetramethoxy-3 4 5 6-dibenz-/J = -cyctoheptatriene (XI ... 

Another alteration is the proposed 7-membered ring in the formula of colchicine which receives substantial support from a preliminary announcement just made by Buchanan, Cook, Loudon and MacMillw that they have synthesised 9 12 18 14-tetramethoxy-8 4 5 6-dibenz-ji 6.. cycZoheptatriene-7-one and shown it to be identical with the a -unsaturated ketone obtained by oxidation of deaminocolchinol methyl ether. 

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