chemistry

Sedaxane

Sedaxane 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 Sedaxane rather than just read about it. In short: Sedaxane is a broad spectrum fungicide used as a seed treatment in agriculture to protect crops from fungal diseases. It was first marketed by Syngenta in 2011 using their brand name Vibrance.

Key takeaways

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

Reference excerpt

Sedaxane is a broad spectrum fungicide used as a seed treatment in agriculture to protect crops from fungal diseases. It was first marketed by Syngenta in 2011 using their brand name Vibrance. The compound is an amide which combines a pyrazole acid with an aryl amine to give a succinate dehydrogenase inhibitor (SDHI). The compound is widely registered for use, including in Australia, the EU, UK and US.

History Inhibition of succinate dehydrogenase, the complex II in the mitochondrial respiration chain, has been known as a fungicidal mechanism of action since the first examples were marketed in the 1960s. The first compound in this class was carboxin, which had a narrow spectrum of useful biological activity, mainly on basidiomycetes and was used as a seed treatment. By 2016, at least 17 further examples of this mechanism of action were developed by crop protection companies, with the market leader being boscalid, owing to its broader spectrum of fungal species controlled. However, it lacked full control of important cereal diseases, especially septoria leaf blotch Zymoseptoria tritici.

A group of compounds which did control septoria were amides of 3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid. These included fluxapyroxad and pydiflumetofen as well as sedaxane.

Synthesis Sedaxane combines the acid chloride of the pyrazole carboxylic acid with a novel amine derivative which was made from 2-chlorobenzaldehyde.

A base-catalysed aldol condensation between the aldehyde and cyclopropyl methyl ketone forms an α,β-unsaturated carbonyl compound which, when combined with hydrazine gives a dihydropyrazole derivative. Further treatment with potassium hydroxide forms the second cyclopropyl ring and this material is converted to the aniline required for sedaxane formation by Buchwald–Hartwig amination using benzophenone imine in the presence of a palladium catalyst, followed by hydroxylamine. Owing to a lack of stereoselectivity in the formation of the second cyclopropane ring, sedaxane consists of two diastereomers: two pairs of enantiomers which are cis–trans isomers. The commercial product consists of >80% of the trans isomers.

Mechanism of action SDHI of this type act by binding at the quinone reduction site of the enzyme complex, preventing ubiquinone from doing so. As a consequence, the tricarboxylic acid cycle and electron transport chain cannot function.

Usage Sedaxane is used as a seed treatment to control, for example, common bunt, Rhizoctonia species and Ustilago species (smuts). As a result, it has potential use in crops including cereals, cotton, potato and soybean. As of 2023 it is registered for use in Argentina, Australia, Canada, Chile, China, the EU, Mexico, the UK, Uruguay and the US.

Human safety Sedaxane has low toxicity and its use was found to leave no residues in human food: however the Codex Alimentarius database maintained by the FAO lists the maximum residue limits for it in various food products.

Resistance management Fungal populations have the ability to develop resistance to SDHI inhibitors. This potential can be mitigated by careful management. Reports of individual pest species becoming resistant are monitored by manufacturers, regulatory bodies such as the EPA and the Fungicides Resistance Action Committee (FRAC). The risks of resistance developing can be reduced by using a mixture of two or more fungicides which each have activity on relevant pests but with unrelated mechanisms of action. FRAC assigns fungicides into classes so as to facilitate this and sedaxane is frequently used in combination with other active ingredients as seed treatments.

Brands Sedaxane is the ISO common name for the active ingredient which is formulated into the branded product sold to end-users. Vibrance is the brand name for Syngenta's suspension concentrate.

References

Illustrations

Worked examples

Example 1 — a first encounter with Sedaxane

Start with the simplest possible case. Write down what Sedaxane 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 Sedaxane 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 Sedaxane 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 Sedaxane

In research: Sedaxane 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 Sedaxane 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: Sedaxane is common in secondary-school and first-year university syllabi. It links to neighbouring topics Anilides, Cyclopropanes, Difluoromethyl compounds, so understanding it makes those chapters shorter.
In everyday life: Look for Sedaxane 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 Sedaxane in 20 minutes

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

Frequently asked questions

What is Sedaxane in simple terms?

Sedaxane is a broad spectrum fungicide used as a seed treatment in agriculture to protect crops from fungal diseases. It was first marketed by Syngenta in 2011 using their brand name Vibrance.

Why does Sedaxane 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 Sedaxane?

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 Sedaxane.