chemistry

Radafaxine

Radafaxine is a chemistry 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 Radafaxine rather than just read about it. In short: Radafaxine (developmental code GW-353,162; also known as (2S,3S)-hydroxybupropion or (S,S)-hydroxybupropion) is a norepinephrine–dopamine reuptake inhibitor (NDRI) which was under development by GlaxoSmithKline in the 2000s for a variety of different indications but was never marketed. These uses included treatment of restless legs syndrome, major depressive disorder, bipolar disorder, neuropathic pain, fibromyalgia…

Key takeaways

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

Reference excerpt

Radafaxine (developmental code GW-353,162; also known as (2S,3S)-hydroxybupropion or (S,S)-hydroxybupropion) is a norepinephrine–dopamine reuptake inhibitor (NDRI) which was under development by GlaxoSmithKline in the 2000s for a variety of different indications but was never marketed. These uses included treatment of restless legs syndrome, major depressive disorder, bipolar disorder, neuropathic pain, fibromyalgia, and obesity. Regulatory filing was planned for 2007, but development was discontinued in 2006 due to "poor test results".

Pharmacology

Pharmacodynamics Radafaxine is described as a norepinephrine–dopamine reuptake inhibitor (NDRI). In contrast to bupropion, it appears to have a higher potency on inhibition of norepinephrine reuptake than on dopamine reuptake. Radafaxine has about 70% of the efficacy of bupropion in blocking dopamine reuptake, and 392% of efficacy in blocking norepinephrine reuptake, making it fairly selective for inhibiting the reuptake of norepinephrine over dopamine. This, according to GlaxoSmithKline, may account for the increased effect of radafaxine on pain and fatigue. At least one study suggests that radafaxine has a low abuse potential similar to bupropion.

Chemistry Radafaxine is a potent metabolite of bupropion, the compound in GlaxoSmithKline's Wellbutrin. More specifically, hydroxybupropion is a major metabolite of bupropion that is further metabolized via an intramolecular cyclization to give radafaxine as the (2S,3S) isomer, as well as the corresponding (2R,3R) isomer isomer, which is less pharmacologically active as a monoamine reuptake inhibitor than radafaxine. Manifaxine (GW-320,659) was developed as an analogue of radafaxine and has been studied for the treatment of ADHD and obesity.

See also List of investigational antidepressants (2R,3R)-Hydroxybupropion 3-Chlorophenmetrazine Manifaxine

References

External links Media related to Radafaxine at Wikimedia Commons

Illustrations

Worked examples

Example 1 — a first encounter with Radafaxine

Start with the simplest possible case. Write down what Radafaxine claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In chemistry, 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 Radafaxine 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 Radafaxine 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 Radafaxine

In research: Radafaxine appears in chemistry 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 Radafaxine 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: Radafaxine is common in secondary-school and first-year university syllabi. It links to neighbouring topics 3-Chlorophenyl compounds, Abandoned drugs, Alcohols, so understanding it makes those chapters shorter.
In everyday life: Look for Radafaxine 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.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Radafaxine in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Radafaxine 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 Radafaxine out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Radafaxine in simple terms?

Why does Radafaxine matter?

Because it connects several chemistry 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 Radafaxine?

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 Radafaxine.