Bisnordihydrotoxiferine

Of the numerous alkaloidal constituents ( 60) of the stem bark of Strychnos dolichothyrsa, six have so far been identified, including five bis-strychninoid ones 102 these are bisnordihydrotoxiferine, bisnor-C-curarine, bisnordihydrotoxi-ferine mono- and di-Xb-oxides, and (tentatively) bisnor-c-alkaloid D. 

The acquisition of complete H and 13C correlation spectral data for known compounds such as 9 isolated from Strychnos myrtoides [85], bisnordihydrotoxiferine (10) and longicaudatine (11) and the main tertiary indole alkaloids previously isolated from Strychnos. atlantica [86],... 

Extracts of S. dolichothyrsa show marked muscle-relaxant activity, and contain a wide range (>60) of alkaloids. Bis-strychninoid alkaloids that are present include bisnordihydrotoxiferine, bisnor-C-alkaloid H, and caracurine Bisnordihydrotoxiferine is also found in the root bark of S. variabilis, together with strychnobiline (265), isostrychnobiline (266), and 12 -hydroxy-isostrychnobiline (267). As an internal carbinolamine ether, strychnobiline can be hydrolysed by acid to the component aldehyde and amino-alcohol, which are 18-deoxydiaboline and desacetylretuline since these bases also occur in 5. variabilis, the possibility that (265) is an artefact cannot be excluded. 

Strychnobaihonine (156) (Figure 26) was isolated from the roots of Strych-nos icaja (Loganiaceae), together with two known bisindole alkaloids, sungu-cine (159) and bisnordihydrotoxiferine (161) (see Figure 27), and a trisindole alkaloid, strychnohexamine."" Strychnobaihonine (156) was a bisindole... 

Known bisindole alkaloids, sungucine (159), isosungucine, strychnogu-cine C (160), bisnordihydrotoxiferine (161), and Nb-chloromethosungucine... 

Matopensine (400), a new symmetrical dimeric indole which stains red with Ce(IV) reagents, was isolated from the African S. matopensis and S. kasengaensis (188 60 61). The structure was elucidated by NMR spectroscopy, which revealed a symmetrical dimer, and indicated a similarity with bisnordihydrotoxiferine (287), which was also present in the plant. The mass spectrum yielded the formula C38H42N4O, differing from 287 by addition of water. The absence of the 16,17-unsaturation in 400, coupled with the observation of the C(17)s as oxymethines ( h 5.3, Sq 82.7), and the... 

As artefacts, dimers that are readily formed from monomeric precursors under mild conditions are obvious candidates, and the presence of acid during work-up can have far-reaching effects. In the bis-tertiary series, with ordinary methods of alkaloid extraction using acid, it is usually not possible to isolate bisnordihydrotoxiferine (4c), since it is highly labile and under such conditions rapidly isomerized and oxidized. However, Delle Monache et al. 

No quaternary bases 0.061% diaboline, 0.027% jobertine Ca. 6% bisnordihydrotoxiferine Quaternary bases absent 0.065% diaboline, 0.0032% 11-methoxydiaboline 0.26% Quaternary bases mavacurine 0.08% Impure macusine B 0.10% 11-methoxydiaboline... 

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