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Modern antifungals like Posaconazole trace their roots back through decades of careful chemical exploration. The intermediate 1-(4-Aminophenyl)-4-(4-Hydroxyphenyl)Piperazine didn’t spring up overnight. In the late 20th century, researchers began scrutinizing the potential of piperazine derivatives because of their solid performance in pharmaceuticals. Early investigations focused on how modifying phenyl rings with functional groups like amino and hydroxy could tweak the molecule’s pharmacological kick. By the 1990s, teams working on azole antifungals realized one core problem: side-effects and fungal resistance called for new structures. Around this time, piperazine intermediates like this one began playing larger roles in active synthesis strategies. Researchers forged pathways for this specific compound so it could streamline the creation of Posaconazole, producing enough for both experimental work and industrial application. Continuous refinement of these synthetic routes bolstered supply reliability, allowing for cost efficiencies and scale-up from bench to plant.
1-(4-Aminophenyl)-4-(4-Hydroxyphenyl)Piperazine falls under the class of substituted piperazines. Chemists appreciate it for the way the hydroxy and amino groups take up symmetrical positions on opposite aromatic rings. That specific setup brings out desirable reactivity profiles and opens routes for further links and modifications. In many labs focusing on antifungal drug synthesis, this compound shows up as a crystalline solid or fine powder, ready to plug into multi-step processes. Its presence often signals a pivot point between basic molecular frameworks and finished, biologically active azoles. Companies in the pharmaceuticals space treat this intermediate as a backbone piece.
Gravity and solubility give practical chemists a lot to work with. This compound typically appears off-white or pale in color, which speaks to the absence of major impurities. Melting points clear the 250°C mark, making it stable under typical storage but also manageable for controlled reactions. Its molecular weight sits at 255.3 g/mol. This matters both for material input calculations and managing yields during scale-ups. The phenolic hydroxy and aromatic amino groups enable solubility in polar organic solvents—think ethanol, dimethylformamide, or even occasionally water under specific pH adjustments. Good chemical stability keeps it from degrading under normal shelf conditions, and it doesn’t throw out any strong odorous hints, helping maintain safer workspaces.
Every bottle or drum of 1-(4-Aminophenyl)-4-(4-Hydroxyphenyl)Piperazine comes with some core specs. Purity usually pushes past 98% by HPLC testing, a benchmark allowing researchers and production chemists to keep reaction side-products to a minimum. Moisture content rests at less than 0.2%, since excess water can wreck or reduce yields during coupling reactions later on. Typical specification sheets list controlled impurity profiles—especially for metals and related byproducts—pointing to compliance with ICH-Q3A/B guidelines. Labels carry CAS numbers, batch codes, net weight, storage hints, hazard statements and pictograms, aligning with GHS standards. From my own handling experience, safety data sheets spell out PPE requirements, environmental measures, and storage temp ranges, making it clear this isn’t your average household chemical.
Building this piperazine usually starts from 1,4-dihalogenated benzene derivatives. Through a nucleophilic aromatic substitution, chemists link piperazine to each ring, introducing hydroxy and amino functionalities through nitration or reduction and hydrolysis of precursors. A common route: reduce 4-nitrophenylpiperazine to its amine, protecting other sensitive groups along the way. The hydroxyphenyl portion’s introduced by precise ring substitution, then deprotected in final steps. Each stage demands careful temperature and pH control—a lesson learned through personal trial and error, as one slip leads to tars, low yields, or tough-to-purify mixtures. In most plants, operators lean on batch reactors and standardized protocols to avoid surprises and ensure each kg batch matches documentation.
Chemists value this intermediate for the chemistry it unlocks. The phenolic group lends itself to etherification, acylation, or oxidative coupling, setting up secondary or tertiary modifications. The amino group reacts with carbonyls, isocyanates, and sulfonyl chlorides for further elongation or cross-coupling. Both functionalities support building the triazole backbone in the final steps of Posaconazole synthesis, allowing for high selectivity and minimal unwanted byproducts. My time in process chemistry showed me the importance of modular groups: making one tweak to either ring greatly expands the library of test compounds—vital for both patent strategies and fine-tuning biological activity.
Ruefully, chemical names never roll off the tongue. Other sources call this material 4-[4-(4-aminophenyl)piperazin-1-yl]phenol or N-(4-hydroxyphenyl)-N’-(4-aminophenyl)piperazine. Certain catalogs might drop trade names or internal codes, reflecting the confidential tracking systems bigger manufacturers use. It’s always been a juggling act to keep up with numbering systems or local regulatory databases, where synonyms sometimes spark confusion at border checks or during tech transfer between labs.
Working with exposed aromatic amines and phenols brings inherent risks. Lab protocols stress the need for gloves, eye protection, and, for scale-up, solid local ventilation. The compound triggers mild to moderate irritation if it comes in contact with skin or eyes, so training on accidental exposure response remains ongoing in all facilities I’ve worked in or visited. Waste streams sometimes carry traces of unreacted amines or phenols, and best practice routes those to incineration or authorized destruction to minimize ecological impact. Typical facilities maintain tightly logged use, storage, and disposal records in line with OSHA and EU REACH standards. Emergency measures, including spill kits and eyewash stations, reduce risks—consistent with the best practices stressed by international safety organizations.
This piperazine intermediate finds nearly all its value as a stepping stone in posaconazole’s production. Without it, manufacturers wrestle with longer, more expensive routes or lower product yields. Down the line, related intermediates plug into other antifungal or CNS-active drugs, taking advantage of the piperazine core. Lab researchers often snag small amounts for medicinal chemistry screening projects. In my own drug discovery work, having access to intermediates like this cut months off exploring what tweaks to side-chains mean for activity or safety. Some recent publications cite modified analogues explored for kinase inhibition or serotonin receptor affinity, though these uses stay mostly at preclinical or bench level for now.
Research groups keep striving for greener, more cost-efficient routes for making this compound. Catalysts, continuous flow reactors, and new protecting group strategies have shown real progress in cutting down both waste and energy use. Open literature from the last five years highlights enzyme-catalyzed synthesis—showing promise in avoiding harsh chemicals and lowering environmental costs. Several patent filings propose crystalline salts or co-crystals to refine solubility and processability in subsequent steps. Corporate teams, especially those tied to generics giants, throw resources at process optimization, sometimes shaving cents per gram but gaining serious leverage when making metric tons annually.
Safety studies flag aromatic amines as watchpoints because long-term exposure to similar chemicals can bring carcinogenic risk. Animal models show mild to moderate acute toxicity via oral and dermal routes, but the compound’s robust structure stops it from breaking down to more dangerous fragments. Most facilities restrict access to qualified staff, reinforce the use of PPE, and run ongoing health monitoring programs. Toxicological data collected during Posaconazole regulatory submissions back up these hands-on precautions; the compound itself doesn’t show strong mutagenicity or reproductive toxicity. Still, the lack of widespread chronic exposure data keeps regulatory scrutiny high, with ongoing reviews as part of broader pharmaceutical safety audits.
More sustainable, lower-cost manufacturing practices are reshaping the future for intermediates like this one. Pharmaceutical companies, driven by regulations and cost pressure, lean heavily on digital modeling, process intensification, and data automation to drive both quality and output. Advanced analytics shed light on potential impurities and degradation pathways, giving chemists firmer control from raw material to active ingredient. Innovations in catalysis and bio-based feedstocks might shrink both carbon footprints and manufacturing times. With antifungal resistance posing a growing threat, related piperazine analogs stand poised to play larger roles as scaffolds for the next wave of potent agents. My experience suggests that close connections between process chemists, toxicologists, and regulatory experts will unlock both safer products and smoother approval cycles in the years ahead.
Digging into the process of making Posaconazole, it’s clear why 1-(4-Aminophenyl)-4-(4-Hydroxyphenyl)Piperazine comes off as indispensable. For anyone unfamiliar, Posaconazole helps prevent and treat fungal infections, saving lives for folks with weaker immune systems. It’s an antifungal powerhouse, but its chemical complexity demands precise, reliable intermediates at every step.
This compound doesn’t just drop by chance. It forms a crucial building block. Without it, the assembly line hits a snag. The nitrogen atom and the hydroxy group in its structure help snap vital connections. I’ve seen synthesis plans—one misstep spells trouble, making the whole process more costly and slow. Researchers and process chemists lean on this molecule to snap the right links in place, advancing the chain toward a finished antifungal drug.
Big pharma companies keep chasing greater efficiency. Timelines for getting medication to those who need it push every step under a microscope. That’s where this intermediate fits. Its use isn’t flashy—no viral headlines—but without it, batches risk impurities and lower yields. I’ve read about troubleshooting in labs; often, the root boils down to the quality and consistency of key intermediates. In my experience with tight production schedules, using a consistent intermediate prevents expensive reruns and, far more importantly, helps avoid shortages of essential medicine.
I’ve watched manufacturers face tough calls sourcing this chemical. Quality matters. Supply chain disruptions during global crises threaten more than just profits—they could mean treatment delays for real people. Chemists must choose suppliers with strong documentation and transparent manufacturing histories. Regulatory bodies don’t take risks lightly, and they shouldn’t. Cutting corners with sub-par intermediates simply isn’t an option.
Safe, traceable supply chains reduce risks across the board. Producers need rigorous quality checks and often invest in analytical technologies to confirm purity before each synthesis run. Labs using chromatography and spectroscopy flag problems fast. From what I’ve seen, heavy investment in staff training and supplier partnerships pays off, both in fewer recalls and in stronger trust with regulators.
Researchers constantly search for greener, more sustainable synthesis routes. This isn’t just for good press; tighter regulations mean old ways eventually get retired. Some academic labs explore alternate routes that skip certain hazardous reagents, but for now, this piperazine intermediate remains core to the playbook. Sharing new findings openly—at conferences or in journals—helps the wider industry adopt safer and cleaner processes faster.
Missing or tainted intermediates don’t just slow science or eat budgets; they threaten real progress. Workers, patients, and their families all rely on every molecule in that supply chain doing its job. Investors and regulators watch closely, but the end users feel the impact the most. As someone who’s watched lab-floor tension during a recall, I know how serious even a small slip-up can be. The quieter work of perfecting intermediates like 1-(4-Aminophenyl)-4-(4-Hydroxyphenyl)Piperazine deserves more recognition.
A lot of people see “99% pure” stamped on a bag and shrug—close enough, right? That number holds a lot of weight in the real world. I remember buying lab reagents as a graduate student, always eyeing those purity certificates. One simple number could mean the difference between a perfect reaction and hours wasted on a failed experiment. That small percentage of impurity can change how a chemical behaves, and in some cases, those impurities can cause real problems down the line.
A batch of aspirin can contain trace contaminants left from the manufacturing process. A few parts per million of certain metals could trigger side effects or allergic responses. Pharmacists and food producers follow rigid rules for this reason. Regulatory bodies like the US FDA and the European Medicines Agency work to ensure that chemicals used in foods and medicines don’t carry unwanted hitchhikers. But even outside medicine, think of lithium for batteries, or silicon for microchips—microscopic contaminants cost companies millions, or render a device unreliable.
Purity often gets described in percentages. “Reagent grade,” “technical grade,” or “pharmaceutical grade” appear on labels, but every field sets its own bar. Researchers trust independent lab analyses to verify what’s really in the product. Labs use analytical tools—spectroscopy, chromatography, titration—so people can trust the results printed on those certificates. These tests examine not just the amount of the main chemical, but also what else sneaks into the sample.
I once ran an experiment using “lab grade” sodium chloride. My reaction worked ten times with one jar, but failed miserably with a different batch from another supplier. Closer investigation revealed traces of magnesium and calcium. That tiny difference threw everything off. The lesson stuck: trust, but verify.
In the digital age, buyers now have more power to demand transparency. Certificates of analysis are often available for download, and some companies publish lab reports for every batch. For those who rely on these products—be it for research, industry, or healthcare—that kind of openness can mean better outcomes. The science behind those numbers should always be accessible, and it should stand up to public scrutiny.
Not everyone in the supply chain pays enough attention to purity. Some distributors repackage bulk materials, sometimes without proper testing. Education is key. Regulators need to do regular spot checks. Manufacturers have to keep lines clean and equipment free of cross-contamination. Standards must rise equally everywhere, not just in countries that enforce harsh penalties.
For anyone using fine chemicals—students, engineers, health workers—it pays to ask questions. Check certificates, push for better documentation, and don’t let price alone sway the final choice. Quality always comes with accountability. The science depends on it, and so does safety.
1-(4-Aminophenyl)-4-(4-Hydroxyphenyl)Piperazine doesn’t show up in most kitchens, but it plays a role in research labs across the world. Folks use it for its properties in pharmaceutical development, and every chemist treats storage like a serious job. Leaving chemicals out or handling them wrong leads to ruined samples—or dangerous situations.
Anybody who works with active compounds knows that even small mistakes can set research back by weeks. Some chemicals react with air, others break down in light, and some send volatile fumes through a room if left open to the environment. This one has amine and hydroxy groups, which tells you moisture, heat, and light could start trouble. A bottle left without care gets clumps, color changes, or, worse, failed reactions. Wasted time and wasted money hurt any lab, big or small.
People sometimes think “colder is always better.” For many organic compounds, including this one, refrigeration—between 2 and 8 degrees Celsius—brings stability. Freezing can draw water in when pulling a bottle from ice, making the material clumpy or hard to work with. Room temperature can work only if the environment never swings wildly. A consistent fridge works best, especially if humidity stays low inside. Based on my time in academic and industrial labs, the difference between cold storage and a forgotten shelf can mean tossing a whole batch.
Some researchers ignore moisture, figuring everything stays dry in a capped bottle. Moisture sneaks in with every opening. This molecule’s hydroxy and amino groups love to attract water from the air, leading to degradation or sticky samples. A dry box or a tightly sealed container with desiccant packs offers a reliable line of defense. In a busy lab, keeping a chemical in the original airtight vial—tucked inside a sealed bag with a fresh silica packet—makes all the difference.
Strong direct light breaks down certain compounds over time, even through thick brown bottles. Light damages aromatic groups like those in this molecule, sparking slow changes that show up as yellow tinting or worse performance. I always stow these chemicals away in an opaque cabinet or at least keep them in their dark glass containers, far from sunlight or bright bulbs.
Some chemicals seem to play nice together, but others don’t. Piperazine derivatives, for example, should avoid strong acids, bases, and oxidizing agents. A dedicated shelf or drawer for amines, far from oxidizers or anything that could trigger unexpected reactions, keeps things predictable. In my experience, careless shelving habits lead to more broken containers—and more paperwork—than almost anything else in a lab.
Mislabeling costs more than people realize. Grabbing the wrong bottle or losing track of when you opened a vial often leads to confusion or, worse, a full restart. Whenever I handle specialty chemicals, I log the date opened, new expiration date, and any change in appearance. This habit makes inventories quicker and stops small problems before they turn big.
Fancy storage equipment only matters if people follow the basic rules. Consistent cool temperatures, low humidity, protection from light, and clear labeling go farther than complicated systems. Chemical suppliers always include their handling advice—those sheets aren’t just paperwork. After years around research labs, I trust simple, disciplined storage routines more than any high-tech gadget.
Large-scale drug making often hits a critical point: getting reliable supplies of key intermediates. Years spent working with pharma manufacturers taught me sourcing is just as tough as the science. You may find the perfect building block for a new drug, but if it’s not available in large amounts at the right quality and within a predictable delivery window, dreams of full-scale production start to fade.
Demand doesn’t wait. If a new therapy shows clinical promise, manufacturers scramble to line up every ingredient, including intermediates, in quantities enough for commercial launch. Pharma giants sometimes spend months chasing leads for obscure chemicals. Availability in bulk becomes more than a logistics question. Investors, patients, and even entire healthcare systems can feel the ripple effects if that link breaks.
Regulatory bodies like the FDA and EMA have set clear rules, but those rules mean little if companies can’t get what they need in time. That’s not just an inconvenience. Delays can cost millions, or worse, limit access to critical treatments.
Most intermediates come from outside North America and Europe. India and China have scaled up capacity over the past two decades, and they dominate production. It’s not just a question of price. Fewer regulations around waste and labor, easy access to feedstock chemicals, and broad manufacturing know-how made these regions the go-to spot.
Political tension and export controls shake things up. In 2020, the world saw supply lines tested during the early pandemic scramble. Suddenly, the comfort of global supply chains turned into a risk, with companies desperate for any domestic backup.
I’ve reviewed dozens of certificates of analysis and seen major differences between batches, even from respected suppliers. Quality control’s only as strong as the weakest operator on a given shift. This isn’t just an annoyance. Impurities that once seemed trivial can trip up an entire downstream process, requiring time-consuming and expensive fixes.
Securing bulk intermediates calls for more than shopping around. A serious pharma operation develops long-term supplier relationships, audits factories, and sometimes co-invests in facilities. Some firms now keep safety stock or even bring limited manufacturing in-house for the most critical intermediates.
Digital platforms and new marketplaces, which started out with basic catalogs, are slowly getting smarter. Transparent track and trace systems, better documentation, and pooled sourcing have started to help smaller companies punch above their weight.
Smarter regulations could also help. Streamlined review for overseas suppliers who clear high EU or FDA standards would bring in more players without lowering safety standards. With growing interest in decarbonizing pharma, green chemistry offers a path too: if a new synthesis cuts out several toxic reagents or uses renewable feedstocks, it not only helps the planet but can localize supply and cut lead times.
Anyone serious about drug manufacturing quickly learns that dependability in bulk sourcing separates talk from action. As demand grows for innovative medicines, every choke point in the upstream chain will keep drawing scrutiny. Reliable access to intermediates isn’t just an operational detail. It’s the foundation for trust in the entire system — for manufacturers, regulators, and patients alike.
In my years working around chemicals in labs and factories, one thing always stands out—people often rush. They think they remember the routine so well that one shortcut won’t matter. Yet, almost every accident I’ve seen starts with someone skipping basics. Each chemical has its own hazards, whether it burns skin, triggers explosions, or pumps out toxic fumes. Even if a product label looks like a math problem, paying close attention to those warning symbols saves pain and money in the long run.
I never touch a new substance without covering up. Gloves and goggles are standard, but sometimes folks forget the simple lab coat, or they wear shorts and open shoes. It’s tempting in the summer heat, but I’ve witnessed chemical splashes stain skin for life. Proper footwear, long pants, and lab coats aren’t just for a polished look—they keep acids and solvents from turning a small error into a trip to the ER.
Ask anyone who’s worked with harsh solvents: breathing them in for an hour leaves a headache that lingers all day. Fume hoods, vents, or even just cracking a window keep vapor concentrations from becoming a health hazard. OSHA data shows long-term exposure to fumes can impact memory and lung health, even at levels where you barely smell anything.
Handwritten scribbles on a bottle lead to confusion, and confusion fuels danger. Clear labels help the team avoid mistakes at a glance, especially in mixed workplaces where two chemicals look the same. Seeing someone mix container contents because their handwriting faded off the side made me rethink how important it is to use permanent markers and waterproof tape for labels.
Spills happen fast. The last place anyone wants to scramble for is the store room hunting for an absorbent pad or neutralizer. In my lab, we kept spill kits near every station. Read over the procedure for cleaning up the chemical you use—some powders kick up dust clouds, some liquids eat through gloves. Always store cleanup materials where you can grab them within seconds.
People underestimate the value of a buddy system. You can have the most careful worker in the world, but all it takes is one accident—fainting from fumes, splashing corrosive on eyes—and you need someone there to call for help. I always make sure at least two people are in the lab when handling anything stronger than a simple cleaner. Buddy systems don’t just save lives, they speed up response when seconds count.
Every close call carries a lesson. I keep a notebook, jotting down accidents or even times I almost made a mistake. Reporting unsafe conditions doesn’t make enemies; it keeps the next shift from learning things the hard way. OSHA encourages this habit, and over my career, I’ve watched it keep teams sharp and companies out of legal trouble.
It’s easy to coast after ten years in the field and think you know every chemical inside out. New hires especially need regular reminders, but even veterans find value in updated training on everything from new regulations to different equipment. Real expertise comes from a cycle of learning, practicing, and teaching others what you’ve learned from every small slip or success.
| Names | |
| Preferred IUPAC name | 4-[4-(4-aminophenyl)piperazin-1-yl]phenol |
| Other names |
1-(p-Aminophenyl)-4-(p-hydroxyphenyl)piperazine 4-(4-Hydroxyphenyl)-1-(4-aminophenyl)piperazine Posaconazole Intermediate 1 p-Aminophenyl-p-hydroxyphenylpiperazine |
| Pronunciation | /wʌn-fɔːr-əˈmiːnəˌfɛn.əl-fɔːr-haɪˈdrɒk.siˌfɛn.əl-paɪˈpɛr.əˌziːn/ |
| Identifiers | |
| CAS Number | 1076198-18-1 |
| Beilstein Reference | 5228283 |
| ChEBI | CHEBI:139857 |
| ChEMBL | CHEMBL2177309 |
| ChemSpider | 21542727 |
| DrugBank | DB08715 |
| ECHA InfoCard | ECHA InfoCard: 100.123.996 |
| EC Number | No EC Number assigned. |
| Gmelin Reference | 1369737 |
| KEGG | C16297 |
| MeSH | C21H23N3O2 |
| PubChem CID | 16360024 |
| RTECS number | VW6650000 |
| UNII | QGX9P34D0G |
| UN number | UN3467 |
| CompTox Dashboard (EPA) | DTXSID20836073 |
| Properties | |
| Chemical formula | C16H19N3O |
| Molar mass | 334.41 g/mol |
| Appearance | White to off-white solid |
| Odor | Odorless |
| Density | 1.19 g/cm³ |
| Solubility in water | Slightly soluble in water |
| log P | 2.7 |
| Acidity (pKa) | 9.41 |
| Basicity (pKb) | 3.77 |
| Magnetic susceptibility (χ) | -83.98×10^-6 cm³/mol |
| Refractive index (nD) | 1.646 |
| Dipole moment | 4.87 Debye |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 472.3 J·mol⁻¹·K⁻¹ |
| Std enthalpy of combustion (ΔcH⦵298) | -3146 kJ/mol |
| Hazards | |
| Main hazards | Harmful if swallowed. Causes skin irritation. Causes serious eye irritation. May cause respiratory irritation. |
| GHS labelling | GHS07, GHS08 |
| Pictograms | GHS07 |
| Signal word | Warning |
| Hazard statements | H302, H315, H319, H335 |
| Precautionary statements | P264, P270, P273, P280, P301+P312, P305+P351+P338, P330, P501 |
| NFPA 704 (fire diamond) | 1-2-0 |
| Flash point | 150.2°C |
| LD50 (median dose) | LD50 (median dose): >2000 mg/kg (rat, oral) |
| REL (Recommended) | 8 hours |
| IDLH (Immediate danger) | IDLH not established |
| Related compounds | |
| Related compounds |
1-(4-Aminophenyl)piperazine 4-(4-Hydroxyphenyl)piperazine 4-Aminophenol 4-Hydroxyaniline Posaconazole |
