Molecules at an Exhibition ~Coniine~

        Coniine is a poisonous alkaloid (a group of compounds that include basic nitrogen atoms) that has a chemical formula of C₈H₁₇N. This structure is very similar to other alkaloids like nicotine, and affects the peripheral nervous system, often inducing a short-lived feeling of well-being followed by depression. If not flushed out of the body in time, it can cause paralysis and fatality. As the natural source of this compound is Poison Hemlock, a plant very closely related to vegetables like carrots, parsnips, and parsley, it is often mistaken for these other plants. It is toxic to humans and all livestock; less than 0.2 grams of this toxin proves fatal in humans via respiratory paralysis, and due to their undeveloped immune systems, children are the most at risk from poisoning. In the course of history, it has been used as a form of capital punishment, for instance, to kill the Greek philosopher Socrates.

(Can you tell the difference between the parsnip plant (top) and the poison hemlock (bottom)?)

It has been known to be a poison since antiquity, as can be seen in its role in Socrates’s execution. The first successful synthesis of coniine was carried out by Ladenburg in 1886. He first heated methylpyridinium (a six-membered resonance ring with a nitrogen ion attached to a methyl group) iodide to obtain 2-methyl pyridine (the latter which denotes the six-membered nitrogen ring). After further treatment, they finally obtained coniine, which is composed of a six-membered, non-resonance ring with a nitrogen atom (a piperidine) with a propyl group attached in the second position, giving it a scientific formula of 2-propylpiperidine. It is soluble, and in its liquid form is colourless, odorous, and has a burning taste. 
   

 The Death of Socrates by Jacques-Louis David

Its common name is derived from the Greek word “konas” which means to whirl about, as one of the main symptoms of coniine poisoning is unsteadiness. It paralyzes muscles by blocking the neuromuscular receptors and causes flaccid paralysis. Although paralysis occurs within half an hour, because it does not affect the central nervous system, the victim stays conscious during the paralysis, until it causes cessation of breath. Other symptoms of poisoning include headache, profuse sweating, and tachycardia. It also has an addictive affect, similar to that of nicotine. In fact, grazing animals have shown a preference for conium-containing foliage after surviving initial exposure, up to the point of eventual death.

 
It is such a cool molecule, especially since it contains a cyclic component, an aspect that is very mesmerizing - we find these molecules that can form bonds that end up joining up with the first atom truly demonstrate the chic, cool aspect to chemistry, and this type of beauty in the structure is part of what makes it our favorite molecule.