Conium, maculatum

Coniine (12), impHcated by Plato in the death of Socrates, is the major toxic constituent of Conium maculatum L. (poison hemlock) and, as pointed out eadier, was apparendy the first alkaloid to be synthesized. For years it was thought that coniine was derived from lysine (24), as were many of its obvious relatives containing reduced piperidine nuclei and a side chain, eg, peUetierine (46). However, it is now known (99) that coniine is derived from a polyketooctanoic acid [7028-40-2] (138), CgH QO, or some other similar straight chain analogue. 

The common hemlock, Conium maculatum, contain five alkaloids. Power and Tutin found a similar mixture in fool s parsley, and a volatile alkaloid resembling coniine i.s stated to occur in certain aroids. According to Svagr, water hemlock Cicuta virosa) owes its poisonous properties to toxin and not to cicutine, a name sometimes used as a synonym for coniine. The toxic properties of hemlock juice have been known ftom very early times thus it was the chief ingredient in the poison administered to criminals by the Greeks. The leaves and the unripe fruits are the parts used in medicine. The following are the names and formulae of the alkaloids —... 

Flcckfieber, n. spotted fever, specif, typhus, fleckig, a. spotted, speckled, stained, mottled, flawy freckled. — — warden, spot, stain. Fleck Schlerling, m. poison hemlock (Conium maculatum). seife,/. scouring soap. stein,... 

Sub-acute, chronic mastitis Hepar sulfuris, Mercurius solubilis, Silicea, Calcarea carbonica, Carbo vegetabilis, Conium maculatum... 

In ancient times, poison-hemlock seed was collected green, dried and stored to be used medicinally as a sedative. The dried leaf and juice of Conium maculatum L. (Hemlock) were listed in pharmacopoeias of London and Edinburgh from 1864 to 1898, and the last official record appeared in Great Britain in the British Pharmaceutical Codex of 1934. Interest in the medicinal value of poison-hemlock has declined because of the unpredictability of its effects. The unpredictability is now understood, the toxin profile and concentration in the plant and green seed can vary dramatically because of environmental factors or, even, diurnally. 

Figure 2.2 Three piperidine alkaloid teratogens from Conium maculatum (poison-hemlock) (a) coniine, (b) y-coniceine, and (c) A-methyl coniine, with accompanying LD50 as determined in a mouse bioassay.

Figure 2.3 (a) Skeletal defects and (b) cleft palate induced in a newborn goat by maternal ingestion of coniine (Conium maculatum), anabasine Nicotiana glauca) or ammoden-drine Lupinus formosus). 

Keeler, R.F. and Balls, L.D. (1978). Teratogenic effects in cattle of Conium maculatum and conium alkaloids and analogs,. Clin. Toxicol., 12, 49-64. 

Banter, K.E. and Keeler, R.F. (1989). Biperidine alkaloids of poison hemlock (Conium maculatum), in Cheeke, B.R., Ed., Toxicants of plant origin, Vol. I Alkaloids, CRC Bress, Boca Raton, pp. 109-132. 

Neurotoxic - death Poison hemlock (Conium maculatum) Coniine - neurotoxic alkaloid -poison used by Socrates... 

Acetate-derived alkaloids Umbelliferae Conium maculatum Coniine... 

Piperidine alkaloids such as coniine and (—)-coniceine are very poisonous. They occur in hemlock (Conium maculatum L.), known as a very toxic plant. One of the characteristics of these piperidine alkaloids is smell. Moreover, they are neurotoxins which have acute effects such as chronic toxicity. 

L6pez, T. A., Cid, M. S. and Bianchini, M. L. 1999. Biochemistry of hemlock (Conium maculatum L.) alkaloids and their acute and chronic toxicity in livestock. A review. Toxicon, 37 841-865. 

Bowman, W. C. and Sanghvi, I. S. 1963. Pharmacological actions of hemlock (Conium maculatum) alkaloids. Journal of Pharmacy and Pharmacology, 15 1-25. 

Heterocycles which are not biosynthesized in humans, but which are natural products produced by other life forms, are very important in the history of drug design. This is particularly true of alkaloids containing a piperidine ring. These include coniine (8.87, extracted from poison hemlock, Conium maculatum, a member of the Umbelliferae carrot family), atropine (from Atropa belladonna and other genera of the Solanaceae plant family the plant was called belladonna [ beautiful woman ] since it was used by... 

Coniine is a poison found in the spotted hemlock, Conium maculatum. This type of hemlock is found commonly throughout the United States and the world, including SLO County. White disperse flowers on a long purple stalk are routinely mistaken for its nontoxic look-alike - the edible wild parsnip. It was a hemlock brew which Socrates... 

Alkaloids are widespread in plants and include some very well-known poisons (notably coniine and strychnine), hallucinogens (morphine, cocaine and muscimol) and other potentially lethal compounds that are nevertheless used in medical practice (e.g. atropine, codeine, colchicine and morphine). As indicated by the preliminary snap-shot above, alkaloids typically have names ending in -ine and which are often related to the plant source or properties. Thus, morphine was named after Morpheus (the God of sleep) and coniine derives from Conium maculatum (hemlock), the plant used in the judicial murder of Socrates (399 BC). Various chemical tests for alkaloids are used as preliminary indicators of alkaloid presence in crude plant extracts. Finally, it should be noted that alkaloids can also exist as jVoxides of the alkaloid base. 

Propylpiperidine Conium maculatum (hemlock) displacement (70) [paralytic,... 

Carum carvi, Conium maculatum, Falcaria vulgaris [root], Oplopanax chironium, Petroselinum crispum, Saposhnikovia divaricata (Apiaceae), Hedera helix (Araliaceae)... 

Plato, 427-347 bc reported the death of Socrates (470-399 bc) by hemlock (Conium maculatum). 

An alkaloid obtained mainly from the fruits and leaves of hemlock, Conium maculatum (Umbelliferae). 

Roberts, M.R (1981) Enzymic synthesis of coniceine in Conium maculatum chloroplasts and mitochondria. Plant Cell Rep., 1,10-13. 

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