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

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An unusual reaction was observed when CXIII was treated with hot sulfuric acid; a mixture of acids was produced. The structure of one, CXVII, containing only three methoxyl groups, was deduced from its spectra and empirical formula. Since CXIV also produced CXVII the eliminated methoxyl was shown to be the one a t C-16. Decarboxylation occurred upon melting to give the p,y-unsaturated ketone (CXVIII), which seemed to rearrange to the corresponding a,p-unsaturated ketone (CXIX),although none could be isolated.

This methylation is remarkably stereospecific in that only the secondary hydroxyl of the five-membered ring was methylated while the ring A hydroxyl was left untouched; when heated, the selectivity is lost and the dimethyl derivative is obtained. The 14-0-methyldelcosine thus produced was identical with delsoline and this constitutes a correlation between the two alkaloids so that the complete structure of delsoline can now be represented as CVII. The occurrence of delsoline is also apparently fairly widespread, as recent reports show that it is found in Consolida regalis ( 1 8 , 5 7 )and also in the seeds of Delphinium orientale (58, 59), where it occurs with delcosine.

Another of the bases isolated by Goodson (44) was an acetylated alkaloid tentatively named “ alkaloid B,” which gave rise to “alkaloid C” on hydrolysis. Thus “alkaloid B ” is monoacetyldelcosine (46). The alkaloids lucaconine and monoacetyllucaconine, isolated from the roots of A . Likewise, the identities of “Takao base 1,” from A . japwnicum Decne. The alkaloid prcviously reported as Shimoburo base 11,from A . japonicum (56)is identical with 14-dehydro- 1. THE C I S -ALKALOIDS ~ ~ ~ ~ ~ 27~ delcosine (54, 55).

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