Strychnine-containing

Strychninic Acids fStrychnic Acids). Although strychnine contains two atoms of nitrogen, it behaves as a monoacidic base. Warmed with a solution of sodium ethoxide it takes up a molecule of water, forming strychninic acid, which crystallises in minute needles, m.p. 215°,... 

Many other alkaloids are used with various applications. One of them is strychnine, an alkaloid known to be strongly toxic to animals. Drugs such as Dysurgal or Pasuma contain strychnine in clinical doses. Strychnine-containing drugs are used in many disorders, including those of the eye. 

Jackson, G., and Diggle, G. (1973) Strychnine-containing tonics. British Medical Journal, 2,176-177. 

Nuts have many uses, both industrial and domestic. For instance, the ivory nut, or tagua, is a source material for the manufacture of buttons and turnery articles. The kola nut supplies ingredients for popular cola beverages in the United States (see Carbonated beverages). StTychnos nux-vomica provides the important medicine and poison, strychnine. The areca or betel nut is chewed by the Indian and Malayan people as a narcotic a slice of the nut is placed in a leaf of the pepper plant Piper betle) together with a pinch of lime the mixture is an acrid, astringent narcotic that dyes the mouth red, blackens and destroys the teeth. The areca nut contains, among other alkaloids, arecoline, an active anthelminthic widely used in veterinary practice for the treatment of tapeworm infections. 

Strychnine, the most celebrated member of the Strychnos alkaloids, possesses a complex polycyclic structure which is assembled from only twenty-four skeletal atoms. In addition to its obvious architectural complexity, strychnine s structure contains a contiguous array of six unsymmetrically substituted tetrahedral (asymmetric) carbon atoms of which five are included within one saturated six-membered ring. The intimidating structure of the strychnine molecule elicited the following remark by Sir Robert Robinson in 1952 For its molecular size it is the most complex substance known. 5... 

Fig. 1 Reflectance scan of a nux vomica extract (A) and a reference chromatogram containing 1 gg each of strychnine and brucine (B). Start (1), brucine (2), strychnine (3), front (4).

We became particularly interested in strychnine when we noticed that the tetracycle 21 (Scheme 4.6), which might be readily available by an intramolecular Diels-Alder cycloaddition of a tryptamine-derived aminodiene, contains much of the complexity of this popular alkaloid target. In fact, this tetracycle is common to many indole monoterpene alkaloids including members of the Strychnos, Aspidosperma, and... 

Many people believe that organic or natural psychedelics such as peyote, magic mushrooms and marijuana are safer or produce better trips than synthetic compounds. This is almost certainly false, since any plant material contains hundreds of compounds, many of which have a definite toxicity, but few of which have psychedelic properties (they tend to make you sick, not stoned). The various impurities or the additives (e.g., amphetamine, belladona, strychnine) sometimes found in synthetic preparations are probably no more toxic than many of the compounds found in the psychedelic plants, and like these compounds, such additives or impurities probably have relatively little effect on the trip. 

The bases generally employed in such resolutions have been natural alkaloids, such as strychnine, brucine, and ephedrine. These alkaloids are more complex than the general case shown in the figure, in that they contain several chiral centres (ephedrine is shown in Section 3.4.4). Tartaric acid (see Section 3.4.5) has been used as an optically active acid to separate racemic bases. Of course, not all materials contain acidic or basic groups that would lend themselves to this type of resolution. There are ways of introducing such groups, however, and a rather neat one is shown here. 

Mandelic acid with a 13 - 20 % enantiomeric excess of the (R)-isomer has been obtained from reduction of phenylglycolic acid in aqueous alcohol buffers containing strychnine in low concentration. The optical yield depends upon pH and is highest (20 - 24 %) at pH 0 or 9.2 and at low current density. In the pH range 2-4, the optical yield drops to 2-8% [42]. The higher result compares well with the maximum value of 20% excess R-isomer found from reduction of (-)-menthyl phenylglycolate in aqueous buffers where the (-)-menthyl ester is the only chiral reagent present [43 ]. 

Plants have provided several other important pesticides. The group of insecticides called pyrethrums was harvested and refined from chrysanthemums. The plant nux vomica contains strychnine, which was used to kill rodents. Rotenone, another important insecticide was extracted from the root of Denis eliptica. Plant extracts were useful, but difficult to purify and obtain in quantity. Significant increases in the use of pesticides occurred with advances in synthetic chemistry and our understanding of biology. 

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