The infrared spectra of a number of secor~dary bases and of their salts have been examined. 'l'he spectra of the salts differ from those of the corresponding bases in containing several absorption bands that are absent fro111 the latter.
Illdole-3-aldehyde, indole-3-carboxylic acid and its ethyl ester were reduced by excess lithium alumir~um hydride to skatolc. The expected reduction product, 3-hydroxyrnethylindole, was obtained by the action of sodi~1111 hydroxide on grarnine rnethiodide. I t and its alkyl ethers were readily reduced to skatole. 3-Hydroxy~nethylindole ur~dernrent self-co~ldensation to 3.3'-di-indolylmethane in neutral and alkalille media, and with acidic reagents was collverted to a n oxygen-free polymeric substance. T h e mechanism of these reactions and of the hydrogeriolysis is discussed.In the course of the investigation of various indole alkaloids anomalous products were obtained on reduction of 3-substituted indole derivatives with lithium aluminum hydride. Thus the action of this reagent on simple indole compounds was investigated with the rather surprising result that indole-3-carboxylic acid, its ethyl ester, and indole-3-aldehyde were reduced in ether solution under very mild conditions to skatole. I t was also found that 3-acetylindole was reduced to 3-ethylindole.There have been a few isolated reports of the hydrogenolysis of acids and carbonyl compounds with lithium aluminum hydride to methyl or methylene groups. Witkop (40) found that an o-aminoketone (spirocyclopentane-1,2'-pseudoindoxyl) was reduced to an oxygen-free amine. Conover and Tarbell (7,8) showed that various benzene and thiazole acids and carbonyl derivatives underwent hydrogenolysis when there was an amino -group ortho or para to the group being reduced. Jones and Kornfeld (15) reported the hydrogenolysis of a carbethoxy group to a methyl in a pyridine derivative. Many of these reductions, however, were carried out for a prolonged time and a t a high temperature, and it was possible to isolate the expected alcohol by employing less vigorous conditions. But with 3-carbethoxyindole, even when less than the theoretical amount of lithium aluminum hydride to cause reduction to the alcohol was employed, the only products isolated were skatole and unreduced ester. I t was thus of interest to prepare by another method the 3-hydroxymethylindole which was apparently very readily reduced b17 lithium aluminum hydride. 'Manuscript
Tryptophan-3-C1" was prepared from methyl labelled sodium acetate and fed to mature iVigella darrtasce?ta L. plants. Radioactivity was translocated throtrghout the plant, but no activity was detected in the clamascenine isolated from it. Similarly the radioactive t r y p t o p h a~~ \\,as fed to pea seedlings and trigonelline detected in the plant extracts. This was also inactive, and these results are discussed.I t has been suggested (23) t h a t trigonelliile (the n~e t h g~l betaine of nicotinic acid) arises from proline by ring opening to 6-aminovaleric acid and thence to nicotinic acid by reaction with a one carbon fragment such as formic acid. Iilein and Linser (18, 18) injected various amino acids into the hollow stems of Dnlzlin vnriabilis and other plants which produce trigoilelline and they claimed t h a t the amount of trigonelline increased, relative to t h a t in control plants, after the feeding of ornithine, proline, glutainic acid, or 6-aminovaleric acid. N o increase was observed after feed-ing arginine, tyrosine, aspartic acid, or other ainino acids. Hexamethyleile tetramine produced increases in the amount of alkaloid, possibly by acting as a source of formic acid. These results have been critically examined by Jaines (15) \illlo raised doubts about the supposed increases in the arnount of alltaloid.Barger (3) was the first to place clamascenine (the methyl ester of 2-methylai11ino-3-n1etl1oxybenzoic acid) amongst the alkaloids derived from tryptophan by the oxidation of indole to anthranilic acid followed by hydroxylation and methylation. In aniinals and rnolds it has been concl~~sively proved t h a t 3-h~~droxyanthranilic acid and nicotinic acid arise in the course of tryptophan metabolisnl (4,6,14,20). RiIany biological reactions which occur in plants have been shown to be similar to if not identical with those occurring in animals and molds. I t was thus conceivable that tryptophan might be the source not only of damascenine, but also of trigonelline. I t was therefore decidecl to feed tryptophan labelled with C14 in the 3-position of the indole n u c l e~~s t o plants producing damascenine and trigonelline. If tryptophan were the precursor of these allialoids radioactivity would be expected in the carboxyl group of both trigonelline and damascenine.
The ultraviolet spectra, basic strengths, and N-alkyl gro~lps of the aconite alkaloids are discussed. Pvropseudaconine has been shown to contain a conjugated system. The formulition C19H19-21(0H)J(OCHJ)dNC2H5 has been confirmed for lycoctonine. Study of its oxidation products has shown that lycoctonine has a methylene group adjacent to the nitrogen and a primary hydroxyl group. The two remaining hydrosyls have been shown to be vicinal, with one probably secondary and the other tertiary. A carbinolalnille structure is suggested for hydrosylycoctonine. The new bases, isolycoctonine, desoxylycoctonine, and des-(oxyn1ethylene)-lycoctonine are described. INTRODUCTION--Aconitum 1ycocton.um (31) and many Delphiniz~m species (6,11,12,24,27,30,36,37) have been shown to contain derivatives of the polyhydroxy base lycoctonine. This base was chosen for an attempt to elucidate the structure of the more highly hydroxylated aconite and delphinium alkaloids since it occurs in both genera, it has an empirical formula representative of the group (Table I), and it is relatively accessible. A number of empirical formulae have been assigned to lycoctonine, i.e., 31,35,36,37), CzoH3305N (25), C241-14107N (6), and C26H4307N (30). The present work supports the C25 fornli~lation, but the analyses do not make it possible t o reach a decision between the H39 and H41 possibilities.If no double bonds are present the H39 formula requires a seven ring structure
ABSTRAC'I'Feeding dl-tyrosine-2-C14 t o sprouting barley res~llted in the formation o f radioactive hordenine and N-methyltyramine in the roots. Isolation and degradation o f these allcaloids showed that all the activity was located in t h e a-carbon aton1 o f the side chain, thus indicating that tyrosine is a precursor o f N-methyltyra~nine and hordenine.
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