chemistry

Latamoxef

Latamoxef 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 Latamoxef rather than just read about it. In short: Latamoxef (or moxalactam) is an oxacephem antibiotic usually grouped with the cephalosporins. In oxacephems such as latamoxef, the sulfur atom of the cephalosporin core is replaced with an oxygen atom.

Key takeaways

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

Reference excerpt

Latamoxef (or moxalactam) is an oxacephem antibiotic usually grouped with the cephalosporins. In oxacephems such as latamoxef, the sulfur atom of the cephalosporin core is replaced with an oxygen atom. Latamoxef has been associated with prolonged bleeding time, and several cases of coagulopathy, some fatal, were reported during the 1980s. Latamoxef is no longer available in the United States. As with other cephalosporins with a methylthiotetrazole side chain, latamoxef causes a disulfiram reaction when mixed with alcohol. Additionally, the methylthiotetrazole side chain inhibits γ-carboxylation of glutamic acid; this can interfere with the actions of vitamin K. It has been described as a third-generation cephalosporin.

Synthesis Oxa-substituted third generation cephalosporin antibiotic (oxacephalosporin).

The benzhydrol ester of 6-Aminopenicillanic acid (6-APA) is S-chlorinated and treated with base whereupon the intermediate sulfenyl chloride fragments (to 2). Next, displacement with propargyl alcohol in the presence of zinc chloride gives predominantly the stereochemistry represented by diastereoisomer 3. The side chain is protected as the phenylacetylamide; the triple bond is partially reduced with a 5% Pd-CaCO3 (Lindlar catalyst) and then epoxidized with mCPBA to give 4. The epoxide is opened at the least hindered end with 1-methyl-1H-tetrazole-5-thiol to put in place the future C-3 side chain and give intermediate 5. Jones oxidation followed in turn by ozonolysis (reductive work-up with zinc-AcOH) and reaction with SOCl2 and pyridine give halide 6. The stage is now wet for intramolecular Wittig reaction. Displacement with PPh3 and Wittig olefination gives 1-oxacephem 7. Next a sequence is undertaken of side chain exchange and introduction of a 7-methoxyl group analogous to that which is present in cephamycins and gives them the enhanced beta-lactamase stability. First 7 is converted to the imino chloride with PCl5 and then to the imino methyl ether (with methanol) and next hydrolyzed to the free amine (8). Imine formation with 3,5-di-t-butyl-4-hydroxybenzaldehyde is next carried out leading to 9. Oxidation with nickel(III) oxide gives iminoquinone methide 10, to which methanol is added in a conjugate sense and in the stereochemistry represented by formula 11. The imine is exchanged with Girard's reagent T to give 12, and this is acylated by a suitable protected arylmalonate, as the hemiester hemiacid chloride so as to give 11. Deblocking with aluminium chloride and anisole gives moxalactam 14.

References

Illustrations

Worked examples

Example 1 — a first encounter with Latamoxef

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

In research: Latamoxef 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 Latamoxef 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: Latamoxef is common in secondary-school and first-year university syllabi. It links to neighbouring topics 4-Hydroxyphenyl compounds, Acetaldehyde dehydrogenase inhibitors, Carboxylic acids, so understanding it makes those chapters shorter.
In everyday life: Look for Latamoxef 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 Latamoxef in 20 minutes

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

Frequently asked questions

What is Latamoxef in simple terms?

Why does Latamoxef 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 Latamoxef?

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 Latamoxef.