314 Essays in Biochemistry 



of a new, non-acetylatable hydroxy group in the precursor XVII of 

 the indanone provided the information that the oxidic bridge of jervine 

 was attached in ring D to the tertiary carbon atom 17. It is interesting, 

 and perhaps of biogenetic significance, that this feature renders XVII, 

 and generally "open" derivative of this type, prone to undergo re- 

 arrangements catalyzed by alkali in which the nitrogen atom, after 

 losing its acetyl group by N — > migration to that hydroxyl group, 

 adds to an activated and sterically favored site in ring D. Thus XVII 

 on O-deacetylation with cold alkali rearranges to the sterically hin- 

 dered and hence very weak tertiary base XIX, 13 whereas the olefin 

 XX, an acetolysis product of tetrahydrojervine, on hydroxylation with 

 osmium tetroxide and treatment of the adduct with sodium sulfite 

 yields, besides the normal 16,17-glycol, a tertiary amine of type XXI, 14 

 reminiscent of rubijervine. 



A concurrent study of the secondary base veratramine 15 showed that 

 this alkamine was closely related to the acetolysis product XVIII from 

 jervine; in fact it differed from it structurally only by the absence of 

 the 11-keto group. The presence of a preformed benzene aromatic 

 ring, first deduced from the absorption spectrum (Jacobs and Craig, 

 1945), rests on solid chemical evidence, 15 as does the allocation of the 

 two secondary hydroxyl groups to positions 3 and 23, and of the double 

 bond to the 5,6 position. 15 * 16 Structural correlation with XVIII and 

 hence with jervine was achieved through the 5,6-dihydro derivative 

 of XVIII, 17 which proved to be identical with an indanone-like com- 

 pound found among the chromic acid oxidation products of triacetyl- 

 dihydroveratramine. 15 Veratramine is therefore XXII. The finding 

 that on permanganate oxidation it afforded benzene-l,2,3,4-tetracar- 

 boxylic acid, 18 aside from disposing of an earlier expression advanced 

 by Jacobs and Sato 16 which differed from XXII only by inclusion 

 of C-18 in a six-membered ring C, made secure the allocation to posi- 

 tion 17a of the methyl group representing that carbon atom. 



In the sequel Jacobs and Pelletier, 19 through a careful re-evaluation 

 of the absorption spectra of the "abnormal" dehydrogenation products 

 and some of their partly hydrogenated derivatives, came to the con- 

 clusion that the perhydrobenznuorene skeleton should be allowed not 

 only to the two secondary bases but also to cevine and the other 

 tertiary ester alkamines. Particularly indicative in this respect were 

 two large basic fragments from cevine not previously mentioned here, 

 namely, cevanthridine, C25H2-N, and veranthridine, C 2 6H 25 N, now 

 formulated, respectively, as XXIII and XXIV. The characteristic 

 ease with which these compounds formed the corresponding 11 -ketones 



