Tryptamine alkaloids, analysis

Audette et al. performed a gas chromatographic screening of phaiaris species for alkaloids, mainly of the tryptamine type. Samples of 20 g dried plant material were extracted with ethanol in a Soxhlet apparatus, the ethanol was evaporated and the residue dissolved in dilute sulphuric acid. After addition of excess of ammonium hydroxide, the alkaloid bases were extracted with chloroform, and after concentration the gas chromatographic analysis was carried out on packed columns of different polarities, using Teflon tubings. After conditioning of the columns they were silanized with 10 gl of Silyl 8 (Pierce Chem. Co.). The retention times of the alkaloids on the various columns used are given in Table 17.3. 

The bark of Phoebe grandis (Lauraceae) gave the known aporphines, boldine, norboldine, laurotetanine and lindecarpine while the leaves yielded two new alkaloids, phoebegrandines A (26) and B (27) [37], which belong to the rare proaporphine-tryptamine group of compounds exemplified by roehybridine (28) (syn series) and roemeridine (29) (anti series) from Roemeria hybrida [38,39], The structure of 29 was previously established by X-ray analysis [40]. 

Tabernaemontana divaricata (double flower variety) provided an unusual minor alkaloid, voaharine (178), whose structure was established by X-ray analysis [137]. Voaharine is exceptional in being in all probability a tryptamine and jccologanine derived alkaloid but possessing a 3-quinolone instead of an indole chromophore. Voaharine is probably derived from voaphylline (180) (which is also present in the plant) via oxidation and rearrangement and represents the first instance of a 3-quinolone-type alkaloid obtained from Tabernaemontana. Besides these, and the known alkaloids N-methylvoaphylline (181), pachysiphine (tabersonine-P-epoxide) and apparicine, as well as two new bisindoles (vide infra), the plant also provided several new alkaloids of the aspidosperma-type including (-)-mehranine (179), voafinine (182), N-methylvoafinine (183), voafinidine (184) and voalenine (185) which were obtained in minute amounts [138-140]. 

Unwanted admixture alkaloids (such as seem to be encountered in A run do donax, for example) must also be taken into consideration Addendum After this book went to press a Swiss drug laboratory completed a full chemical analysis of the variety of Phalarais arundinacea 1 have been working with. The primary alkaloid here is 5-MeO-DMT a close molecular analogue of DMT itself, P. arundinacea is notorious for extremely wide variations in the tryptamine alkaloids it contains — some varieties have... 

The presence of the keto base (17) in Cinchona plants was confirmed by dilution analysis. C. ledgeriana shoots were allowed to metabolize [1-14C] tryptamine and were then worked up for alkaloids after the addition of inactive (17). The recovered carrier was radioactive, which confirms that the keto-base... 

The new alkaloid, perlol50 ine (CigHigOaNg mp 183° hydrochloride, mp 204r-233°) from this source has the structure 119 as determined by X-ray analysis of its hydrobromide. It has also been synthesized by the condensation of tryptamine with 5-acetoxymethyl-2-formylfuran followed by hydrolysis of the ester group and oxidation of the initial tetrahydro base 149). 

Studies on known alkaloids include one on the AA BB system and the conformational populations of tryptamine and some N-substituted derivatives, and X-ray crystal structure analyses of psilocybin " and psilocin. " In connection with the separation and identification of tryptamine derivatives in the cerebrospinal fluid of schizophrenic patients the g.l.c. analysis of the heptafluorobutyroyl derivatives is recommended success is claimed on picogram quantities of material. ... 

Feeding experiments with doubly labeled [1-3H2, l-14C]tryptamine showed that 50% of the tritium at C-l of tryptamine was lost during the formation of Cinchona alkaloids—a result which indicates that the cleavage between C-5 and N-4 in corynantheal is a stereospecific process. The ring expansion to quinoline must occur via the indolenine (178) and the recy-clization of 179 to furnish cinchonidinone (180), which was found by radiochemical dilution analysis to be a natural product in C. ledgeriana. The specific incorporation of [1 l-3H2]cinchonidinone in cinchonine and quinine and the incorporation of [ll-3H2]cinchonidine in cinchonidinone is best understood by the sequence 180 — 186 and its reversal 186 — 182, as shown in Scheme 7 (95). 

The structure of isocinchophyllamine has been confirmed as (122a) by an X-ray analysis of its methanol solvate. The stereochemistry, relative and absolute, of ochrolifuanines A and B (122b and c) has been settled by partial synthesis involving condensations of dihydrocorynantheal and corynantheidal with tryptamine to give C-3 isomeric pairs, which were separated and one in each case shown to be identical with the natural alkaloid. C.d. measurements then settled the stereochemistry at the C-3 centres. 

As part of a search for naturally occurring substances acting on neurochemical transmission, a new trimeric tryptamine alkaloid, idiospermuline (177), was isolated from the seeds of Idiospermum australiense, occurring in North Queensland, Australia 113). The structure elucidation was based on spectral data and an X-ray crystallographic analysis of its trimethiodide derivative, which also provided the absolute configuration. 

Mcllhenny EH, Pipkin KE, Standish LJ, Wechkin HA, Strassman RJ, Barker SA (2009) Direct analysis of psychoactive tryptamine and harmala alkaloids in the Amazonian botanical medicine ayahuasca by liquid chromatography-electrospray ionization-tandem mass spectrometry. J Chromatogr A 1216 8960-8968... 

---