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In the world of organic chemistry, some molecules don’t get flashy introductions or splashy headlines, yet quietly anchor plenty of lab work and product development. 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone fits this pattern. Developed through decades of research into cyclic urea derivatives, its story tracks broader trends in medicinal chemistry and industrial chemistry. The search for versatile, easily modifiable scaffolds runs deep into the last century—pyrimidinone structures offered a handy platform for exploration. Early chemists noticed their promising hydrogen-bonding behavior and stability, making them appealing not just in theory but in hands-on synthetic work. Over time, the molecule’s accessibility and adaptability brought it into steady demand, showing up in research focused on pharmaceuticals, crop protection, and specialty material science.
The compound stands out for its compact structure. With two methyl groups on the nitrogen atoms, ring saturation, and a retained carbonyl, it manages to be more than the sum of its parts. These features don’t just affect how it reacts in the lab. They influence properties like water solubility, melting point, and capacity to participate in both nucleophilic and electrophilic reactions on demand. Chemists appreciate chemicals that don’t make life too complicated with wild reactivity or unpredictable toxicity, and this compound generally delivers a straightforward, approachable experience in handling and storage—though nothing is entirely risk-free. Factoring in batch-to-batch consistency and labeling makes a real difference for quality control and research reproducibility. Clear labeling on purity—usually expressed in percent, residual solvents, and the presence of isomers—remains critical to minimizing error. Consistent supply lines and transparency matter much more than fancy branding.
So much of a chemical’s value hangs on its physical attributes: solids that don’t clump, powders that don’t turn cake-like in humid air, and liquids that aren’t excessively irritating. This molecule is often found as a white crystalline solid, melting between 85 to 90°C, soluble in many polar solvents, and capable of handling moderate heat before breaking down. It brings a certain reliability—reactions set up with it often follow documented routes without unexpected detours, a feature any bench chemist can appreciate after wrestling with more mercurial reagents. The moderate molecular weight makes it manageable in purification steps, crucial in scaling up lab results to pilot plant runs or small production batches.
It’s easy to underestimate the impact of plain old labeling. A bottle marked simply with a chemical name but missing the CAS number or molecular formula can gum up procurement or compliance processes. In my own experience, coming across half-labeled containers is a headache that wastes as much time as it risks safety. Full disclosure on the label—compound identity, purity range, any hazardous impurities—turns into a simple act of respect for researchers and ensures compliance with safety rules. Proper hazard statements, storage advice, and handling icons prevent missteps, both in research labs and industrial settings. This seems basic, yet gaps still crop up, showing the need for ongoing attention to labeling and information transfer.
Bench chemists gravitate to syntheses that deliver consistent results and scale up with minimal fuss. 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone usually starts with condensation of dimethylurea and a suitable dialdehyde or diester under mild heating. Reaction times don’t sprawl into days, and purification often involves straightforward recrystallization. The ease of synthesis means researchers can whip up what they need or order reliable commercial batches without the logistical headaches that plague more exotic compounds. Straightforward work-ups and purification help labs keep costs under control—a practical win more meaningful than any theoretical efficiency.
The molecule’s cyclic structure and amide functionality give it a balanced profile—reactive enough for derivatization, stable enough to store on a shelf without constant babysitting. Methyl groups on the nitrogens reduce some reactivity, making it less vulnerable to unwanted side-reactions but still open to modifications at the carbonyl or on the ring. I’ve seen it used as a starting material for crafting libraries of functionalized pyrimidinones, building blocks for new ligands, or even as a protected amine source. Reactions like alkylation, acylation, and even ring opening aren’t out of reach, letting chemists tweak structure and tune properties for their own projects. Even small advances in lab methodology—using greener solvents or gentler reagents—have improved yields and reduced waste, progress everyone can support.
Tracking down compounds often turns into detective work, especially when catalog names pile up. 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone appears under synonyms like Dimethyltetrahydropyrimidinone, DMPU (though this acronym applies most accurately to the 1,3-dimethyltetrahydropyrimidin-2(1H)-one variant), or as an N,N-dimethyl derivative in some catalog lists. Mixing up names across suppliers, publications, or regulatory filings wastes time and risks real confusion. Standard nomenclature—always including the CAS number—makes life easier for procurement teams and researchers hunting through literature or inventory systems.
Talking safety doesn’t always get the attention it deserves, right until the lack of it causes accidents or near misses. This compound, solid at room temperature, avoids the volatility problems of many organic reagents, but storage away from direct sunlight and in dry, well-ventilated areas remains a baseline. Material safety data shows moderate concern for eye and skin irritation on contact, prompting glove and goggle use—not negotiable in responsible labs. Any dust or spilled powder needs prompt cleanup, and regular review of storage and labeling policies keeps small oversights from snowballing into incidents. Sound protocols and a culture of care win out over clever workarounds. Real safety gains have come from treating labeling, storage, and disposal as ongoing habits rather than annual checkboxes.
Applications span across research in medicinal chemistry, crop protection, advanced polymers, and solvents for specialty syntheses. Medicinal chemists value the pyrimidinone motif for its bioactive potential, using derivatives to probe enzyme inhibition or new antiviral models. Agrochemical researchers chase improved stability and selectivity in their candidates using similar scaffolds. Polymer and materials scientists test it as a building block for new resins or amide-rich networks. Even with all this, the compound hasn’t become a household name, partly because it’s often a starting block—a molecule that hands off its features instead of dazzling on its own.
The compound’s versatility makes it a prime candidate for scaffolding chemical libraries in drug discovery. Advances in green chemistry have cut the environmental impact of synthesizing related compounds, opening new doors for scalable, responsible manufacturing. Researchers tinker with its core to unlock tweaks in pharmacological profiles: shifting methyl groups, testing substitutions on the ring, or altering ring size and saturation to modulate solubility or binding. Real breakthroughs tend to come from patient, incremental work—applying new tools in computational chemistry or automated synthesis to old problems like target selectivity and metabolic stability. Its steady presence in these efforts shows more impact than hype.
Toxicity gets some attention in lab handbooks, but in industrial or agricultural use, it becomes front and center. Data on 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone suggests moderate, but not severe, acute toxicity. Exposure controls—gloves, eye protection, and careful segregation from incompatible substances—keep incidents rare. Long-term hazard assessments stay active topics in regulatory and research circles, with ongoing studies focused on chronic effects that take years to emerge. The demands of modern safety regulations, covering air pollutants and water runoff, push researchers and producers to minimize emissions, improve waste treatment, and close the loop from product to disposal. Building a safety culture takes vigilance and support from management, not just handbooks on the shelf.
The future often rests on what researchers and companies can accomplish with molecules like this in hand. Ongoing innovations in medicinal chemistry look at more complex versions as enzyme modulators or backbone templates for new classes of drugs. Crops with tailored resistance or synthetic materials with smart-responsive properties depend on subtle chemical tweaks—often only possible with sturdy, modifiable building blocks. The biggest future shifts could involve green synthesis methods, using bio-based starting materials or milder reactions to meet stricter environmental standards. Digital tools—automation, machine learning for reaction planning—promise to cut development time and predict hazards or performance before a single batch hits the flask. Researchers remain on alert for emerging toxicity or environmental persistence, to avoid surprises from yesterday’s miracle molecules. The best progress often comes from discipline: sticking to sound science, demanding transparency from suppliers, and never letting convenience become an excuse. With these habits, advances grow on a solid foundation.
Some chemical names stick in your mind, but 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone does the opposite. The scientific world calls it DMPU. Most people have never heard of it. Those of us with any background in labs come across DMPU once in a while, especially around reactions that call for something a little stronger and safer than old friends like dimethylformamide (DMF). DMPU isn’t household vocabulary, but it can make or break a synthetic process behind the scenes, affecting everything from medicines to materials.
Chemists reach for DMPU when they need a powerful solvent that won’t throw wrenches into their reactions. DMPU holds a spot as a top polar aprotic solvent, especially when reactions require an environment that won’t donate hydrogen atoms (protons) and mess up sensitive molecules. It’s a lifesaver in work with sodium or potassium species, boosting reaction rates and driving tough transformations over the finish line. Anyone who has gotten stuck with low yields using DMF or DMSO has felt the relief when DMPU opens the door to better results.
Pharmaceutical manufacturers use DMPU because it lets them run processes more efficiently and with fewer dangerous byproducts. Unlike DMF, DMPU shows a much lower risk of creating carcinogenic contaminants. That matters a lot with growing concern about the health impacts of residues left behind in finished pills and tablets. Regulatory bodies in regions like Europe keep raising the bar for what’s allowed thanks to tighter safety standards.
I remember coming across DMPU the first time while looking for alternatives for DMF, which leaves a sticky mess on glassware and a real headache during cleanup. DMPU washes out easier, smells less toxic, and has a better safety profile. That counts on a busy production floor, where every minute spent on cleaning means less time making useful products. The Green Chemistry movement keeps touting DMPU as a model case for swapping out old, risky chemicals for safer choices without losing chemical muscle. Less exposure to hazardous fumes in the workplace doesn’t just make life better for chemists—it often helps companies dodge lawsuits, fines, and failed inspections.
No chemical gets a free pass. DMPU pulls high marks for safety compared to some older choices, but disposal, environmental persistence, and cost remain sticking points. It costs more than DMF per kilogram, which starts to pinch at large scales. Replacing old solvents isn’t just about pouring new liquids into reactors—equipment compatibility, availability during supply chain hiccups, and employee retraining all join the conversation. In pharma, even a small tweak can turn into a major headache if it means re-validating established production lines. Not all labs or factories can absorb those costs easily.
If we want wider adoption of safer solvents like DMPU, companies, regulators, and researchers need to pull together. Better incentives for green chemistry, faster approvals for process updates in pharma, and continued funding for safer molecule development all play a role. The next generation of chemists should see DMPU and its successors as the norm, not the exception. Every step away from old hazards is worth celebrating, and getting there calls for a mix of scientific progress, economic realism, and personal accountability on the shop floor and in the boardroom.
Plenty gets made of chemical safety, for good reason. People in research or manufacturing often work with compounds sporting long names, like 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone. While some may treat exotic chemicals with extra caution, there’s a risk of getting too casual about solvents and reagents with less drama on their labels. This one doesn’t set off Geiger counters, but it’s not something to brush off.
There’s not a slick marketing campaign behind this compound, and it won’t make the front page, but it’s showing up in labs across pharmaceuticals, agriculture, and specialty chemical research. Regulatory sheets class it as an irritant. Breathing in the fumes or letting it touch bare skin might not end the workday, but enough exposure often leaves rashes, watery eyes, or a stubborn cough. I’ve met folks who ignored a pair of goggles and ended up with burning eyes for hours. These are the mishaps that quietly dent confidence and productivity.
It’s easy to think splashy hazards only come from corrosives and poisons. Yet, chronic exposure sets up problems that sneak up over time. Reports from seasoned lab workers back this up: someone spends a few years regularly handling mild irritants, and next thing you know, they’re sensitive to things that never bothered them before. Respirators, gloves, and even good old-fashioned lab coats keep that risk down. OSHA recommends standard protective gear for irritant-level solvents, and it’s not just legalese—those guidelines come out of long lists of real workplace injuries.
Nobody walks into the lab planning on getting sick. Still, open bottles, sticky gloves, or splashes mix quickly with a full schedule. I’ve watched colleagues juggle tasks, reaching for a clean pipette only to realize they just smeared their hand across a puddle left on the bench. The mistake rarely spells disaster, but it’s a warning to double-check spills and clean up regularly. Even well-ventilated spaces struggle to keep up when solvents evaporate and join everything else riding the lab air currents.
Facility managers now pay close attention to storage and waste handling for solvents. Containers with tight seals keep vapors from sneaking out overnight. For disposal, capturing used materials in labeled, closed containers keeps staff from tracing odors back to a forgotten beaker tucked away in a hood. In my experience, routine safety checks and short team huddles at the start of each shift do more for safety than anything written in a manual.
The science is clear—no compound, even if it seems “tame,” deserves a cavalier attitude. Getting familiar with Safety Data Sheets, making sure gloves fit, and pulling on a pair of goggles have saved many careers. Cutting corners on small stuff grows into bigger issues over time. Hands stay steady, projects move forward, and people keep showing up healthy, ready to take on the next challenge. That’s what every lab or production floor deserves, no matter what’s in the glassware.
Names of organic molecules might look like puzzles, but they reveal a lot about the chemical itself. When I first came across 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone, what grabbed my attention was its structure. It’s not just another tongue-twisting name. This compound is a heterocycle, something you find constantly when looking into pharmaceutical chemistry or materials research. The hexagon with two nitrogen atoms forms the base—the pyrimidine ring—common to many biologically active compounds.
Break the name into its parts and you see the story in the molecule. “1,3-Dimethyl” tells us that two methyl groups attach to the nitrogen atoms at positions 1 and 3 in the ring. “3,4,5,6-tetrahydro” fills in the picture, meaning hydrogen atoms have saturated four of the ring’s carbons, causing those carbons to lose double bonds and take on a more flexible, non-aromatic character. “2(1H)-pyrimidinone” signals a ketone group at the second position.
To see it in your mind’s eye: draw a six-membered ring. The nitrogens sit at positions 1 and 3. Carbonyl oxygen juts off the second carbon, and methyl groups stick to each nitrogen. Everything else gets filled out with hydrogens—typical for a tetrahydro ring. This gives us a skeleton you’ll see in drug design textbooks and material science lectures. The sum of its pieces brings the molecular formula C6H12N2O.
My laboratory experience tells me why understanding this arrangement matters. A methyl group out of place tweaks physical properties. Drugs with small changes to side groups transform from active to inactive. The carbonyl oxygen acts as a hydrogen bond acceptor, another point chemists target during drug design. When looking at molecules like caffeine or uracil, you find how minor swaps in the ring trigger huge changes in biological effects.
Calculating molecular weight comes straight from the periodic table—add up each atom. Six carbons at 12.01 each, twelve hydrogens, two nitrogens, and one oxygen. The final tally rounds to about 128.17 g/mol. For a synthetic chemist, this is a manageable size; no bulky rings or sprawling chains, just a neat platform for tweaking into analogs. Knowing the weight helps track it in chromatography, balance dosages in the clinic, and keep an eye on purity during synthesis.
Unlocking the secrets of a compound’s structure isn’t just for academic satisfaction. Whether you’re running a synthesis or searching through a pharmacopoeia, precise knowledge of the arrangement and molecular mass keeps you one step ahead. Imagine running a reaction and misidentifying reagents—that leads to wasted material and unknown side products. Mistakes here can reach the scale of wasted weeks or even months, an expensive lesson I learned early on.
Compound databases and chemical suppliers count on accurate naming and structure because downstream research depends on it. A single number out of place, or a missing methyl group, puts entire experiments out of sync. Next time you spot a complex name on a chemical bottle, pick up the periodic table and draw it out by hand. Connecting each functional group to its molecular weight is a simple habit that saves hours later on.
Anyone in chemistry, pharmacy, or manufacturing ends up tracing each compound back to the structure and weight. The more you practice looking beneath the names, the easier it gets to predict outcomes—solubility, reactivity, and even side effects. In my experience, grounding every project with a solid understanding of the building blocks avoids wasted effort and sharpens every result in the lab or on paper.
Dealing with chemicals in a lab teaches you pretty quickly that casual storage habits tend to bring surprise headaches, or worse. Any compound with a name as long as 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone often brings special baggage. This one, valued for use as a solvent and in several pharmaceutical processes, isn’t something to toss on a shelf among half-empty bottles.
You find plenty of caution in chemical handling guidelines for a reason. A single careless placement can mean contamination, unexpected reactions, or exposure that nobody bargaining on. These aren’t imaginary dangers — a simple mix-up once shut down our entire lab for weeks after a container leaked on a humid day, producing sharp odors and putting ventilation through its paces.
A dry spot with solid ventilation works best. Humidity creeps into containers and speeds up hydrolysis, which can weaken or ruin the material. Temperature swings, especially in basement storage areas, push chemicals beyond the safety edge. Keeping this compound around room temperature, usually between 15-25°C, helps avoid both decomposition and unwanted evaporation.
Sunlight does chemicals few favors, especially organic ones. It’s easy to stash bottles by the window for convenience, but that mistake has turned clear liquids murky and forced expensive replacements. The dark, steady environment of a chemical cabinet serves both quality and safety.
A clean, well-marked glass or compatible plastic bottle with a tight cap saves a world of trouble. In shared labs, bold labeling stands between simple oversight and accidents. A clearly visible hazard label helps even someone new to the space understand caution is required.
I once watched a frustrated coworker pour a “nearly empty” bottle of solvent into the wrong waste container, not realizing that trace residues could set off a reaction. That lesson isn’t easy to forget. Keeping 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone away from oxidizers, acids, and incompatible solvents means you dodge surprise reactions. Even small spills can raise indoor air contaminant readings above recommended levels, so keeping related compounds a safe distance apart isn’t just a rule, it’s common-sense prevention.
Improper handling can lead to chemical burns or respiratory irritation. Even well-behaved compounds turn hazardous if lids loosen and fumes leak. Wearing protective gear feels like overkill to some, but a few minutes spent with a burning throat or irritated skin changes that mindset fast. OSHA keeps stats on chemical accidents that mostly boil down to sloppy storage.
Every lab I’ve worked in that prioritized careful chemical management saw accidents drop. Consistency builds trust within teams, and fewer incidents keep insurance rates and maintenance costs from ballooning. If I had to suggest one thing above all else: treat every container as if someone you care about will handle it next. Document every move, close containers tightly, use fresh labels every time, and make routines visible to others.
Small shifts toward safe storage of chemicals like 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone won’t just protect samples. They safeguard health, save money, and turn any lab into a place where people want to work.
Most people don’t encounter chemicals like 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone in their everyday lives, at least not knowingly. The full name rolls off the tongue about as smoothly as gravel. In a lab, it may show up as a solvent or building block in making more complex molecules, and that’s where questions kick in: what do we really know about the side effects? What happens if this stuff gets on your skin, into your eyes, or — worst case — inside your body?
Experience tells me the gap between textbook knowledge and harsh lab experience can be broad. Handling new or obscure chemicals pushes you to dig deeper into safety sheets, academic papers, and sometimes informal stories shared among researchers. Searching through published literature and safety databases for this compound doesn’t turn up mountains of data. There’s a frustrating lack of detailed, peer-reviewed studies. That’s often a red flag: if no one’s published the toxicity data, people can overlook actual risks until an incident forces the issue.
I’ve seen other solvents — even ones with similar structures — cause significant skin irritation, dry out hands, or pose real inhalation hazards. Chemicals that don’t scream “danger” may not seem like a threat, but anyone who has seen the slow impact of repeated low-level exposure knows not to treat any laboratory solvent lightly. Many organic solvents, especially those with nitrogen rings, can be irritating or worse if absorbed. Even “rare” compounds can vaporize, and with possible volatility, inhalation exposures come into play. The way a molecule interacts with proteins or membranes in living tissue matters.
Regulatory agencies and chemical suppliers suggest basic protective gear when handling 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone. Standard gloves, goggles, and good ventilation come up all the time. The reason is simple: without clear chronic exposure data, the safest bet is to reduce contact as much as possible. Some safety sheets point out risk of eye and skin irritation, with no clear evidence for or against more severe outcomes like carcinogenicity or reproductive toxicity. Even so, the silence doesn’t equal safety.
Stories of missed risks are common in lab environments. Not too long ago, I watched a colleague confident in one solvent's low toxicity start having skin problems after repeated exposure. The connection only became apparent after tracing symptoms back through work logs and safety data sheets. That's not a lesson anyone wants to repeat.
Relying on trusted safety data, err on the side of caution. Always use gloves rated for chemical resistance, not just what’s handy. Check ventilation and, if working with volatile amounts, step up to a fume hood or respiratory protection. Quick access to eyewash and showers is smarter than hoping for the best. Document every exposure, and don’t skip medical check-ups if you have symptoms like headaches, skin irritation, or chronic fatigue. Supervisors and lab managers should track newer solvents, keep up communication, and push for access to toxicological reports from manufacturers.
The absence of long-term studies leaves room for surprises, and as seen with many synthetic chemicals, risks may appear after years of use. Open dialogue with suppliers, ongoing research, and transparent training help protect both experienced workers and newcomers. Knowing what you’re handling, and demanding the facts even when a chemical seems obscure, builds a culture that guards health before it’s at risk.
| Names | |
| Preferred IUPAC name | 3,5-Dimethyl-1,4,5,6-tetrahydropyrimidin-2(1H)-one |
| Other names |
Metcamifen 1,3-Dimethylhexahydropyrimidin-2-one 1,3-Dimethyl-3,4,5,6-tetrahydropyrimidin-2(1H)-one |
| Pronunciation | /ˈwʌn, θri daɪˈmɛθɪl ˈθɛtrəˌhaɪdrə tuː pɪˈrɪmɪdɪnˌoʊn/ |
| Identifiers | |
| CAS Number | 702-98-7 |
| Beilstein Reference | 110904 |
| ChEBI | CHEBI:18841 |
| ChEMBL | CHEMBL141637 |
| ChemSpider | 66888 |
| DrugBank | DB06813 |
| ECHA InfoCard | 03a8d8cf-347b-4b12-9157-1a086e404f5e |
| EC Number | 207-361-6 |
| Gmelin Reference | 9274 |
| KEGG | C05843 |
| MeSH | D013073 |
| PubChem CID | 18967 |
| RTECS number | UY7525000 |
| UNII | 7T1C4Y9DJR |
| UN number | UN2810 |
| Properties | |
| Chemical formula | C6H12N2O |
| Molar mass | 128.17 g/mol |
| Appearance | White to off-white solid |
| Odor | Odorless |
| Density | 1.14 g/cm³ |
| Solubility in water | slightly soluble |
| log P | -0.32 |
| Vapor pressure | 0.102 mmHg (25°C) |
| Acidity (pKa) | pKa = 12.0 |
| Basicity (pKb) | pKb = 11.02 |
| Magnetic susceptibility (χ) | -44.3×10⁻⁶ cm³/mol |
| Refractive index (nD) | 1.471 |
| Viscosity | 1.308 mPa·s (25 °C) |
| Dipole moment | 3.74 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 322.1 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | –333.8 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -3994 kJ/mol |
| Pharmacology | |
| ATC code | N06BX13 |
| Hazards | |
| Main hazards | Harmful if swallowed. Causes skin and serious eye irritation. May cause respiratory irritation. |
| GHS labelling | GHS02,GHS07 |
| Pictograms | GHS07 |
| Signal word | Warning |
| Hazard statements | H315, H319, H335 |
| Precautionary statements | P261, P280, P305+P351+P338, P337+P313 |
| NFPA 704 (fire diamond) | 1,2,0 |
| Flash point | > 108°C |
| Autoignition temperature | 387 °C |
| Lethal dose or concentration | Lethal Dose or Concentration (LD50/LC50): LD50 Oral Rat 940 mg/kg |
| LD50 (median dose) | LD50 (median dose): Oral rat LD50: 980 mg/kg |
| NIOSH | DY1575000 |
| PEL (Permissible) | PEL: Not established |
| REL (Recommended) | 10 mg/m3 (NIOSH REL TWA) |
| IDLH (Immediate danger) | Unknown |
| Related compounds | |
| Related compounds |
Barbituric acid Thiobarbituric acid Pyrimidone 2,4,6-Trimethylpyrimidine Phenobarbital |
