science

Methylecgonidine

Methylecgonidine is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Methylecgonidine rather than just read about it. In short: Methylecgonidine (anhydromethylecgonine; anhydroecgonine methyl ester; AEME) is a chemical intermediate derived from ecgonine or cocaine. Methylecgonidine is a pyrolysis product formed when crack cocaine is smoked, making this substance a useful biomarker to specifically test for use of crack cocaine, as opposed to powder cocaine which does not form methylecgonidine as a metabolite.

Key takeaways

Methylecgonidine belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Methylecgonidine to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Methylecgonidine from memory before moving on to harder problems.

Reference excerpt

Methylecgonidine (anhydromethylecgonine; anhydroecgonine methyl ester; AEME) is a chemical intermediate derived from ecgonine or cocaine. Methylecgonidine is a pyrolysis product formed when crack cocaine is smoked, making this substance a useful biomarker to specifically test for use of crack cocaine, as opposed to powder cocaine which does not form methylecgonidine as a metabolite. Methylecgonidine has a relatively short half-life of 18–21 minutes, after which it is metabolised to ecgonidine, meaning that the relative concentrations of the two compounds can be used to estimate how recently crack cocaine has been smoked. Methylecgonidine has been shown to be specifically more harmful to the body than other byproducts of cocaine; for example to the heart, lungs & liver. The toxicity is due to a partial agonist effect at M1 and M3 muscarinic receptors, leading to DNA fragmentation and neuronal death by apoptosis. AEME is also used in scientific research for the manufacture of phenyltropane analogues such as troparil, dichloropane, iometopane, and CFT. Methylecgonidine could also theoretically be used to produce cocaine and so may be a controlled substance in some countries.

Synthesis

Methylecgonidine can be synthesized non pyrolytically from cocaine via hydrolysis/dehydration followed by esterification with methanol.

The scheme by Kline is based on the reaction of 2,4,6-cycloheptatriene-7-carboxylic acid with methylamine. This is a modified version of U.S. patent 2,783,235 by Grundmann and Ottmann. In the accompanying patent U.S. patent 2,783,236 these same authors react their methylecgonidine with two equivalents of PhLi to form a tertiary alcohol by "hard" addition to the ester and not "soft" Michael addition. However, the product is only one tenth the potency of atropine. The methyl 2,4,6-cycloheptatriene-1-carboxylate can be made synthetically.

Davies et al. synthesized (R/S)-methylecgonidine by a tandem cyclopropanation/Cope rearrangement. Thus, reaction of methyldiazobutenoate (2) with 5 equiv of N-((2-(TMS)ethoxy)carbonyl)pyrrole (1) in the presence of rhodium(II) hexanoate/hexane gave the [3.2.1]-azabicyclic system (R/S)-8 in 62% yield. The unsubstituted double bond was selectively reduced using Wilkinson catalyst to provide N-protected anhydroecgonine methyl ester ((R/S)-4). Following deprotection of N8 nitrogen with TBAF and reductive methylation with formaldehyde and sodium cyanoborohydride, (R/S)-5 was obtained in overall good yield.

See also Arecoline Anatoxin-a Tropacocaine Ferruginine

References

Illustrations

Worked examples

Example 1 — a first encounter with Methylecgonidine

Start with the simplest possible case. Write down what Methylecgonidine claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Methylecgonidine before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Methylecgonidine ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Methylecgonidine

In research: Methylecgonidine appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Methylecgonidine in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Methylecgonidine is common in secondary-school and first-year university syllabi. It links to neighbouring topics Cycloalkenes, Methyl esters, Recreational drug metabolites, so understanding it makes those chapters shorter.
In everyday life: Look for Methylecgonidine outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Methylecgonidine in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Methylecgonidine means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Methylecgonidine out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Methylecgonidine in simple terms?

Why does Methylecgonidine matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Methylecgonidine?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Methylecgonidine.