Simple Tyramine Derivatives

Ephedrine, pseudoephedrine, and norpseudoephedrine are now produced primarily by synthesis. Ephedrine is used as a bronchodilator for treating the symptoms of asthma and for treating coughs. Pseudoephedrine and norpseudoephedrine are used for the same purposes and are included in formulae for over-the-counter remedies for treating symptoms of the common cold. All three of these alkaloids cause a rise in blood pressure and this is a deterrent to their use in patients with hypertension. 

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Hasubanonine-like alkaloids are known from the genera Sinomenium and Stephania (Menispermaceae). A biogenetic pathway leading to the formation of hasubanonine (55) and protostephanine (56) has been proposed (Battersby et al., 1974, 1977, 1981a, 1981b, 1981c) (Fig. 32.19). In experiments in which labeled precursors were fed into whole plants, Battersby and co-workers found that simple tyramine derivatives such as 2-(3,4-dihydroxy-5-methoxyphenyl)eth-... 

The relationship between anemone fish, Amphiprion sp., and their sea anemone partners are regulated by alkaloids from the sea anemone. Amphiprion perideraion is attracted to the sea anemone Radianthus kuekenthali by the simple lysine-derived alkaloid amphikuemin (Fig. 12.6 Murata etal, 1986). Other simple alkaloids, aplysinopsin and dihydroaplysinopsin, also attract A. perideraion, regulate its swimming rate and induce their species-specific partnership. A related anemone fish, Amphiprion ocellaris, is attracted to the sea anemone Stoichactis kenti by tyramine (Fig. 12.6) and tryptamine induces searching by the fish (Murata etal, 1986). 

Hordenine and iV-methyltyramine are isolates fix)m the young roots of Hordeum vulgare var. hexastichon (Poaceae), and are simple phenylethylamine-type alkaloids. The biosynthetic precursor of these alkaloids is considered to be tyramine, derived from tyrosine. d/-[2- " C]-Tyrosine was fed to H. vulgare var. hexastichon 4 days after germination, and hordenine and N-methyltyramine were isolated after 11 days from the roots. Both alkaloids possessed label at the a-carbon. It was also found that d/-[2- " C]-tyrosine was more effectively incorporated into N-methyltyramine than into hordenine, and no tyramine was detected in the extract. So, the incorporated tyrosine was converted into tyramine and methylated immediately to give N-methyltyramine. Subsequent steps form hordenine by the methylation of N-methyltyramine [3]. 

There is a relatively large number of alkaloids which maybe considered as simple phenethyl amine [64-04-0] (59, R = H), CgH N, or tyramine [51-67-2] (59, R = OH), CgH NO, derivatives. These iaclude mescaline (61) from the small wooly peyotyl cactus l ophophora mlliamsii (L emaire) Coult. anhalamine (62) and lophocerine (63) from other Cactaceae, and the important antamebic alkaloids (—)-protoemetiae (64), (—)-ipecoside (65), and (—)-emetine (66) from the South American straggling bush Cephaelis ipecacuanha (Brotero) Rich. AH of these bases appear to be derived from tyrosiae (25,... 

Marine tunicates are also a source of brominated tyrosine derivatives. The colonial ascidian Aplidium sp., which was collected in Australia, yielded the novel iodinated tyrosine alkaloids 1973-1975 (1819). Collections of Botryllus sp. and Botryllus schlosseri from the Philippines and the Great Barrier Reef, respectively, have afforded botryllamides A-D (1976-1979) (1820). A Palauan ascidian Botrylloides tyreum produces several new botryllamides, including the brominated botryllamide G (1980) (1821). The simple brominated tyramines 1981 and 1982 were isolated from the New Zealand ascidian Cnemidocarpa bicornuta (1822) and an Indonesian Eudistoma sp. ascidian (1823). 

Many frogs and toads contain high levels of N- and 0-methylated amines derived from the indolic biogenic amines serotonin and tryptamine, as well as other amines, such as the tyramines and catecholamines. Such simple... 

The relation of many of the simpler alkaloids to the aromatic amino acids is obvious. For example, germinating barley contains (241), besides tyrosine and tyramine, A -methyltyramine, JViV -dimethyltyramine (hordenine), and the trimethylammonium derivative (candicine). In this simple case the. AT-methylated derivatives are known to be derivable from isotopically labeled tyramine (538) and the methyl groups are known to arise from methionine by transmethylation (540, 586). Similarly AT-methyl derivatives of phenylethylamine, 3,4-dihydroxyphenylethylamine, and 3,4,5-trihy-droxyphenylethylamine are well known alkaloids (cf. review, 701). N-Methylated derivatives of tryptamine and hydroxytryptamine equally occur for example, eserine has an obvious relation to 5-hydroxy tryptamine. Methylated derivatives of metabolites of the aromatic amino acids also occur, for example, trigonelline (67), which is the betaine of nicotinic acid, and damascenine is probably similarly related to hydroxyanthranilic acid. 

A number of amines derived from aromatic amino acid are present in brain in trace quantities. Since aromatic L-amino acid decarboxylase shows a broad substrate specificity, it is not surprising that compounds such as tyramine, tryptamine, phenylethylamine, and histamine are present in brain. These amines are derived from the simple decarboxylation of the corresponding... 

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