By R.H.F Manske, H.L. Holmes

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This same hydroxyl is also impervious t o mesylation, even though the tertiary C-13 hydroxyl undergoes this reaction smoothly (90).

This was confirmed by alkaline hydrolysis of X X I I t o the corresponding acid, which spontaneously cyclized to the lactone XXIII. Yamada ( 1 4 ) has studied the oxidation of hydroxylycoctonam (XX) with chromic acid and found that it is similar to the lead tetraacetate oxidation of hydroxylycoctonam ( 5 )and isolycoctonam (13)in that the a-ketol bond is cleaved, followed by elimination of a molecule of methanol. Two acid products (XXIVa and XXIVb) and a neutral one (XXV)were isolated from this reaction.

The later microanalysis data suggested that the oxidation proceeded without loss of a carbon atom, thus yielding an N-acetyl compound. However, oxonitine has also been reported as an oxidation product of mesaconitine (79, 80) 42 S. W. PELLETIER AND L. H. KEITH which possesses an N-methyl instead of an N-ethyl. Vigorous treatment of aconitine (partial structure CXXIV) with nitrous acid (81a)resulted in the cleavage of the N-ethyl and formation of the nitroso derivative CXXV. Acetylation of cxxv CXXIV * CHaCHz-N 5 OAc 5 OAc H CXXXI CXXXII CXXV with acetyl chloride gave a mixture of CXXVI and its acetolysis product CXXVII in 14% and 57% yields, respectively.

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