Phenethylamines and simple isoquinolines

The 1-benzyltetrahydroisoquinoline skeleton is one of preeminence in the elaboration of plant alkaloids. Only the terpenoid indole skeleton (Section 6.6.2) appears in more diversely modified form. Among the benzylisoquinolines, reticuline (6.127) is of outstanding importance as a substrate for modification. Formation of the 

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Of the alkaloids so far identified in just L. william-sii alone, 15 are Beta-phenethylamine and simple isoquinoline alkaloids. Mescaline, N-methylmescaline, N-acetylemescaline, anhalamine, anhalonine, anhalidine, anhalinine, anhalonidine, lophophorine, O-methylan-halondedine, and pellotine have all been identified as the principal components of the plant. However, only mescaline has so far been determined to cause hallucinations. 

Chapter 9 ) -Phenethylamines and Simple Isoquinoline Alkaloids By V. A. Snieckus... 

Possibly as a result of the social implications of the hallucinogenic j5-phenethyl-amines and simple isoquinoline alkaloids, a large number of new plant species suspected to contain these structural types have been closely scrutinized with the aid of sensitive analytical methods. Thus, extensive screening of a large variety of cactus species has been carried out. G.c. analysis has indicated the presence of trace amounts of dimers and trimers of phenethylamine and tetrahydroiso-quinoline types " while combination g.c.-mass spectrometry has enabled rapid identification of alkaloids of 120 cactus species." High voltage electrophoresis has been used for quantitative alkaloid determination.Useful structural information may be obtained from the technique of chemical ionization mass spectrometry. ... 

Obviously, under these conditions, it will be quite possible to find bases of the same type in plants of widely separated botanical families or even in products of animal metabolism. The individual cactus alkaloids will be found, therefore, under the headings /8-Phenethylamines (see Vol. Ill, chap. 22) and Simple Isoquinoline Alkaloids (see Vol. IV, chap. 26), where are also included all other natural bases of similar structure but different origin. 

This section is concerned with j3-phenethylamines/ simple isoquinolines, (including 1-phenylisoquinolines) and the Ipecacuanha alkaloids. ... 

According to su estions first made by Pictet and Spengler (1) and later by Spath (2), the substituted /3-phenethylamines may be considered as the precursors of the simple isoquinolines. For example, mescaline and formal-... 

Eleven bases have been isolated from Anhalonium lewinii, three phenethylamines mescaline, V-methylmescaline, and V-acetylmescaline (see /8-Phenethylamines Vol. Ill, chap. 22) and eight simple isoquinolines anhalamine, anhalidine, anhalinine, anhalonidine, pellotine, 0-methyl-d-... 

In Table 1, the families of the species containing simple isoquinolines and isoquinolones are grouped in orders and superorders according to Dahlgren (1975). Species containing only simple isoquinolines are primarily found in the Cactaceae and the Chenopodiaceae of the Caryophyllales and in the Fabaceae (Leguminosae). The species of these three families contain simple isoquinolines as major alkaloids and these often occur together with jS-phenethylamines. 

The simple isoquinolines, anhalonidine (12) and anhalamine (13) are bio nthesized in the peyote cactus along with the hallucinogenic phenethylamine, mescaline (6). It is clear, by inspection, that the isoquinoline alkaloids, (12) and (13), are formed from an Ar-C2-N unit like that seen in mescaline (6) with the inclusion of an additional or C2 unit. 

There is considerable variation in structure between the groups of isoquinoline alkaloids, some being simple isoquinolines while others are complex dimers. About 50 simple isoquinolines occur in plants and they are characteristic of some families such as the Cactaceae. Interest in these compounds has stemmed from the well-known hallucinogenic phenethylamine, mescaline, and in one chapter, the occurrence of these simple isoquinolines is reviewed. 

The isoquinoline alkaloids are the second largest group of alkaloids, numbering about 6000, and can be viewed as five subgroups—the simple tetrahydroisoquinolines, the benzylisoquinolines, the phenethylisoquinolines, the Amaryllidaceae alkaloids, and the monoterpene isoquinolines. In addition, there are a number of simple phenethylamine derivatives, including ephedrine (originally from Ephedra species, but now synthesized) and pseudoephedrine, used for asthma and nasal... 

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