chemistry

RTI-83

RTI-83 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 RTI-83 rather than just read about it. In short: RTI-83 ((–)-2β-carbomethoxy-3β-(4-ethylphenyl)tropane) is a phenyltropane derivative which represents a rare example of an SDRI or serotonin-dopamine reuptake inhibitor, a drug which inhibits the reuptake of the neurotransmitters serotonin and dopamine, while having little or no effect on the reuptake of the related neurotransmitter noradrenaline. With a binding affinity (Ki) of 55 nM at DAT and 28.4 nM at SERT but…

Key takeaways

RTI-83 belongs to chemistry; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect RTI-83 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of RTI-83 from memory before moving on to harder problems.

Reference excerpt

RTI-83 ((–)-2β-carbomethoxy-3β-(4-ethylphenyl)tropane) is a phenyltropane derivative which represents a rare example of an SDRI or serotonin-dopamine reuptake inhibitor, a drug which inhibits the reuptake of the neurotransmitters serotonin and dopamine, while having little or no effect on the reuptake of the related neurotransmitter noradrenaline. With a binding affinity (Ki) of 55 nM at DAT and 28.4 nM at SERT but only 4030 nM at NET, RTI-83 has reasonable selectivity for DAT/SERT over NET

However, further research has shown that by extending the ethyl chain even better selectivity can be achieved, with the 4′-(cis-propenyl) analogue having Ki values of 15 nM at DAT and 7.1 nM at SERT, vs 2800 nM at NET. However RTI-436 has an even better selectivity for DAT over NET (3.09 nM @ DAT and 1,960 nM @ NET, or a NET/DAT ratio of 634.3, but with lesser DAT/SERT equivalent potency with a ratio between them of 108) and RTI-88 has a still better ratio (984 NET/DAT with additionally having less selectivity than the former compound between DAT/SERT and having a more even spread of potency with the ratio between DAT and SERT being 88).

Such drugs are speculated to be useful as potential antidepressants, but few examples have been reported in the literature as yet. However, while RTI-83 has been used for binding studies to model the monoamine transporter proteins, its pharmacology in vivo has not been studied in detail.

See also 4-Ethylamphetamine 4-Ethylmethcathinone UWA-101

References

External links Jin C, Navarro HA, Carroll FI (December 2008). "Development of 3-phenyltropane analogues with high affinity for the dopamine and serotonin transporters and low affinity for the norepinephrine transporter". Journal of Medicinal Chemistry. 51 (24): 8048–56. doi:10.1021/jm801162z. PMC 2841478. PMID 19053748.

Illustrations

Worked examples

Example 1 — a first encounter with RTI-83

Start with the simplest possible case. Write down what RTI-83 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 RTI-83 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 RTI-83 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 RTI-83

In research: RTI-83 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 RTI-83 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: RTI-83 is common in secondary-school and first-year university syllabi. It links to neighbouring topics Ethyl compounds, Methyl esters, Para-Phenylene compounds, so understanding it makes those chapters shorter.
In everyday life: Look for RTI-83 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 RTI-83 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what RTI-83 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 RTI-83 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is RTI-83 in simple terms?

Why does RTI-83 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 RTI-83?

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 RTI-83.