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Amino acids with oxygen functions didn’t show up out of nowhere. Their story stretches back to the fundamental puzzle of how living things tick. Early chemists picked apart proteins, finding certain pieces popped up time after time—pieces like serine, threonine, aspartic acid, and glutamic acid, each including oxygen groups often in the form of alcohol or acid functions. At first, protein chemistry struggled to pinpoint why these oxygenated bits stood out. As techniques evolved, like the use of chromatographic separation and mass spectrometry, research teams began to unravel the deeper roles these specialized amino acids had in cellular signaling, metabolism, and enzyme function. The Nobel-winning protein sequencing efforts by Sanger and later advances sharpened our view: these amino acids weren’t extras in the biochemical drama. They were essential for turning the gears, transferring charges, and binding water—all tasks vital for life as we know it.
In today’s labs, amino acids with oxygen-bearing functions no longer spark confusion but serve as familiar tools and building blocks. Serine and threonine, with their simple hydroxyl-bearing side chains, anchor processes from enzyme regulation to protein stabilization. Aspartic acid and glutamic acid, sporting carboxylic acids, handle charge balance and metabolite transport with a directness that more complicated molecules struggle to match. These amino acids show up in feeds, medical supplements, biotechnological fermentation batches, and food fortification. Their accessibility depends on fermentation yield, purity profiles, and, increasingly, microbial engineering that swaps out classic chemistry for resilient new production strains. Nobody talks about the mystery of their structures now; instead, people focus on how these components ease nutrition gaps or serve as raw material for research.
The physical traits are straightforward. Most of these oxygenated amino acids present as fine crystalline powders, varying in solubility. For example, aspartic and glutamic acids tend toward moderate water solubility under neutral or alkaline conditions due to their carboxyl groups, showing mild acidity, with sharp dissolution point shifts depending on pH. Serine and threonine carry side chains with alcohol groups, improving their water affinity but leaving them sensitive to heat and light in some forms. These acids and alcohols influence how these amino acids behave in proteins—serine and threonine add points for hydrogen bonding, while aspartic and glutamic acids introduce negative charges at neutral pH. These properties turn into practical issues too, like the tendency for certain forms to cake or clump if left in humid environments, and the chance of decomposition if stored in sunlight or under poor temperature control.
Regulatory guidelines keep tight standards on identity and purity, especially in fields like pharmaceuticals and food manufacturing. These amino acids often appear labeled by their common or systematic names, with required notations on purity—often exceeding 98% for pharmaceutical grade. Batch-specific documentation details residual solvents and trace metal levels, reflecting the importance of avoiding contamination in sensitive applications. Labeling for feed additives or food supplements often requires origin disclosure, potential allergens, and concentration per serving or use rate, enforced by authorities such as FDA and EFSA. Safety data sheets flag respiratory or skin irritation potential for industrial users. Poorly labeled supplies bring real risks: misidentified batches can contaminate millions of dollars’ worth of productions, and even small changes in isomer composition affect research results. The industry had to evolve a zero-tolerance mindset, forced by hard lessons from past errors.
Synthesizing amino acids with oxygen functions once relied on laborious extraction from protein hydrolysates, but that approach wasted more of the valuable starting material than it saved. Soon, direct chemical synthesis and, better yet, microbial fermentation took over. Nowadays, companies genetically program microbes to crank out amino acids like serine, threonine, or glutamic acid in vast fermenters using precise feeding regimens—no cows, no pig bladders, just well-trained bacteria and yeast. Once cultures finish, downstream processing steps like centrifugation, pH adjustment, and painstaking filtration get pure crystals. For special research needs, enantiomerically pure forms might come from chiral resolution or clever enzymatic tweaks on precursors. Simple as this process may look in industrial schematics, it disguises a surprising complexity—controlling yield, purity, and low byproduct formation has pushed fermentation engineering’s limits year by year.
Amino acids with oxygen functions attract chemists for their reactive side chains. These groups aren't just decorative: serine’s hydroxyl can be a hook for phosphorylation, changing protein activity or cell signaling pathways. Threonine, with that extra methyl group, cranks up the steric demands, making its modifications even trickier. Aspartic and glutamic acids, holding carboxylates, get tapped for peptide couplings, crosslinking, and cyclization reactions in the synthesis of peptides or small-molecule drugs. Researchers tinker with these features to craft pegylated forms, fluorescent derivatives, and crosslinked biomaterials—spanning antibody-drug conjugates to novel hydrogels. On the flip side, these reactive groups sometimes turn into headaches: unwanted oxidation or polymerization in storage, especially under damp or impure conditions, can wreck a batch and drive up costs.
The world of amino acids is full of nicknames and code numbers. In scientific literature, you spot serine as "Ser" or “HO-CH2-CH(NH2)COOH,” threonine as "Thr," aspartic acid as "Asp," glutamic acid as "Glu"—short, functional, but to the casual observer as cryptic as ancient shorthand. Commercial packaging sometimes lists them using E numbers for food use (E620-E625 for glutamates) or under International Nonproprietary Names (INN) for active pharmaceutical ingredients. The logic seems messy but serves a purpose: clear separation between grades and uses. Misnaming can slip a food-grade raw material into a clinical trial, or a technical grade byproduct into a dietary supplement, with consequences that go beyond an annoyed customer. Facts and records keep quality up and mistakes down.
Handling amino acids with oxygen groups brings less risk than classic toxins but more than pure sugar. Most pose mild irritant risks if dust accumulates, especially in busy production areas. Hygiene matters—clean spills quickly, avoid inhaling dust, keep materials dry and cool to prevent degradation. Regulatory audits don’t cut corners on documentation and lot traceability, partly due to past incidents where poor record-keeping let adulterated lots reach the market. For pharmaceutical or medical uses, manufacturing complies with Good Manufacturing Practices (GMP) or analogous frameworks in food production. Audited suppliers log every step: inputs, operator shifts, temperature swings, and packaging controls. This data-heavy trail means one bad lot can be traced, isolated, and recalled before it snowballs into a larger safety risk.
The practical reach of these amino acids is enormous. Pharmaceutical developers count on them for peptide synthesis and as starting points for antibiotics and cancer drugs. Nutritionists focus on their role as dietary essentials for humans, livestock, and pets, using fortification to address deficiencies that stunt growth or disrupt metabolism. Food technologists value them as taste enhancers, texture improvers, or fermentation boosters—think of glutamic acid in soy sauce or miso, or aspartic acid in meat tenderization. The reach doesn’t stop at chemistry labs. Bioplastic makers and tissue engineers tap into the flexible chemistry of these amino acids for ultralight building blocks. In diagnostic kits, their distinct properties serve as standards or calibration points—simpler and cheaper than full-scale protein fragments.
Research on amino acids with oxygen functions spikes during any wave of investment in biotechnology, personalized nutrition, or materials science. Their functional groups make them prime targets for modification, unlocking new biomaterials or enzyme designs. CRISPR and synthetic biology empower labs to tune bacterial and yeast strains to customize yields or maximize the rate of production with less waste. Instead of old-style trial and error, AI-driven modeling predicts which changes in the metabolic pathway ramp up production or steer outputs to selected forms. University and pharmaceutical teams hunt for new reactions on these side chains—using bio-orthogonal chemistry to label or modulate protein functions in living systems. These advances blend traditional know-how with high-tech insight in a way never imagined fifty years ago.
On their own, the major amino acids with oxygen functions rarely trigger acute toxicity issues. At reasonable doses, they blend into the background of protein metabolism. Yet, more isn’t always better. Overconsumption, especially of glutamic acid in sensitive individuals, can rage up so-called “Chinese Restaurant Syndrome”—transient discomfort, headaches, and tingling. Industrial exposure to dust or solutions calls for respect for the possibility of respiratory irritation or skin reactions, especially among workers handling multi-ton production batches. Recent studies scan for subtler long-term effects, checking metabolic overload or rare allergies, but most headlines about their toxicity melt away on closer reading. The drive for ultra-pure, low-residual byproducts stems from a desire to head off any avoidable risks, not a proven wave of harm.
Amino acids with oxygen functions will stay in focus, shaped by both tradition and the race for sustainable bioproducts. Demand for plant-based proteins boosts the need for affordable, scalable production of key amino acids, including the oxygenated ones—no livestock, no environmental baggage, just robust fermentation and downstream engineering. Individualized medicine and nutrition stand to gain from their use: tailored formulas, fortification for at-risk populations, or even as carriers for targeted drug delivery. Researchers want new versions: stereochemically pure, stable under tough conditions, or tweaked for unique reactions. Regulation and technology push suppliers to refine, not just scale up, nourishing safer, cleaner, and greener chemistry. The road forward runs through quieter revolutions: optimizing microbes, smart process controls, and bolder collaborations between chemists, engineers, and clinicians, all keeping these building blocks ready for whatever next challenge arrives.
Amino acids come in all shapes and forms, some carrying a bit more weight in the science world than others. Those with oxygen functions – like serine, threonine, and tyrosine – take center stage in many everyday processes that most folks don't realize. Whether found in proteins that shape our muscles or tucked away in the enzymes that power up our cells, these particular building blocks do more than help build tissue. They twist, tug, and tweak how our bodies handle nutrients, repair damage, and edge closer to peak health.
Folks working in medicine and nutrition have relied on these amino acids for everything from boosting recovery after injuries to keeping metabolism on track. Serine, for instance, helps nerves talk to each other and keeps our brain sharp. I’ve seen how nutrition plans in sports medicine use this fact to speed up healing or improve performance – athletes looking to bounce back from a sprain or stress fracture often get extra attention paid to these nutrients.
Beyond the gym or clinic, amino acids with oxygen functions serve as tools in research and new drug development. Scientists use them to simulate the twists and turns of enzymes in labs, which pushes forward everything from cancer treatments to new materials. Tyrosine stands as a backbone for signal messengers, helping to trigger hormone release and fire off nerve responses. As researchers look for deeper answers about brain disease or aging, these amino acids give them a piece of the puzzle.
I work around lab research on proteins, and one reality is clear: replacing or tweaking these oxygen-rich amino acids often reveals weak spots in our understanding of cellular life. Each time a study manipulates serine or threonine, the data unlocks unknowns about immune functions, stress responses, or how cells repair DNA. This information doesn’t just stay in journals. Over time, it informs vaccine development and gives pharmaceutical companies clear targets for new therapies.
The food world trusts these amino acids to improve flavors, bind ingredients, and even preserve nutrients during processing. Serine and threonine often enhance the taste and texture of everything from sports supplements to plant-based burgers. These applications don’t grab headlines, but I’ve tasted the difference when manufacturers get the formula right—products that deliver on both nutrition and satisfaction.
Watching trends with plant-based diets, attention has shifted to the fine structure of these amino acids. Producers track how different food sources measure up, looking to close the gap between animal and plant proteins. This becomes crucial in areas like elder nutrition, where getting complete amino acid profiles supports muscle retention and health. Better choices for consumers begin with sound research into these building blocks.
Getting these amino acids into enough products, and doing so affordably, still pushes the boundaries of food safety, supply chains, and quality control. Shortcuts or poor ingredient sourcing can lead to products that miss the mark—causing issues for sensitive populations or those relying on precise nutritional regimens. My experience training dietary staff in elder homes showed me that source quality means everything, and any slip-up can have outsized effects on health.
The solution comes down to deeper collaboration between scientists, food producers, and regulators. Stricter sourcing, better labeling, and clearer science-backed advice can bridge the gap. With more transparency and ongoing research, the benefits of amino acids with oxygen functions spread more widely, offering better outcomes not just in labs or elite athletics but across regular kitchens and communities.
Better understanding and smarter use of these unique amino acids could improve lives in small but meaningful ways, from supporting aging populations to creating healthier, tastier food options. Putting in the work now sets the stage for a future where nutrition and medicine harness the full power of these molecular workhorses.
Walk down the supplement aisle or scroll through fitness forums, and you’ll spot talk of amino acids: glycine, serine, threonine — all with that oxygen group hanging from their backbone. In the world of biochemistry, these fall into the “amino acids with oxygen functions.” They’re parts of our diet, they’re in powders and sports drinks, and the body uses them every day to keep our muscles humming, our brains signaling, and our guts working as they should.
Take glycine as an example. This amino acid, with its side-chain oxygen, acts as both a neurotransmitter and a builder of proteins. Add serine to the list, which the body needs for metabolism and to produce phospholipids for cells. Threonine isn’t just another piece of the protein puzzle; it’s also tied up in our immune and digestive systems.
Eat a typical meal, and you’re getting these amino acids. Chicken, tofu, yogurt, eggs — they’re all packed with them. Your liver breaks down protein, and your blood carries these building blocks where they're needed. Most healthy people don’t need to worry about negative effects just from normal intake.
The story starts to change when supplements enter the picture. Training for a marathon, packing on muscle, or following a strict diet — these moments drive more people to powders and capsules. The trouble pops up with large doses or mixing in these amino acids far above what anyone would get from actual food.
Let’s go back to glycine. Studies show that high doses can lead to nausea or vomiting. Some folks taking threonine and serine notice digestive discomfort. Reports of fatigue and odd tastes in the mouth sometimes make their way into medical journals when the intake gets excessive.
People with inherited metabolic disorders, like those with a serine deficiency or certain enzyme defects, may face risks even at ordinary levels. Anyone with kidney or liver issues should pay attention, since these organs handle the heavy lifting of filtering excess amino acids.
Research on healthy adults keeps shining a light on how much is enough. For example, clinical trials usually dose glycine at five to 15 grams a day. Serine and threonine follow similar lines. Above these amounts, the chance of side effects climbs. Medical professionals have pointed out that the body’s natural control systems can get overwhelmed, leading to odd mental symptoms or metabolic shifts.
This isn’t just theory. PubMed and reputable research centers have documented cases where excessive use, especially in people with chronic conditions, led to headaches, mood changes, and increased stress on the kidneys. Most people do fine, but mega-dosing hasn’t earned a green flag from regulators or nutrition experts.
Most of the worry around amino acids with oxygen functions comes down to dosage. Stick to what healthy eating provides, and supplements rarely disturb the system. Those facing health issues or thinking of heavy supplementation should work with a registered dietitian or medical doctor.
Reading labels and choosing tested supplements matters. The internet is full of bold claims, but clinical research and regulatory approvals tend to be more reliable guides. There’s rarely a need to chase the latest amino craze — a varied, colorful plate does the trick for almost everyone.
People talk about protein and amino acids all the time. Less common is a discussion about the specific types, like amino acids with oxygen functions. Tyrosine, serine, threonine, asparagine, glutamine, and similar neighbors fall in this category. Growing up lifting weights and playing sports, I remember thinking all amino acids did pretty much the same thing. With better science, it’s clear they play unique roles, especially those with oxygen, which often help with brain chemistry and energy production.
Just scooping any supplement doesn’t mean your body puts it all to work. The timing, what you eat with it, and the quality of the amino source matter if you want real results. Eating lean chicken or eggs in a meal sticks with people as classic advice. As research came out, it painted a more nuanced story. For athletes or folks recovering from injury, specific amino acids, especially those with oxygen functions, speed up recovery, regulate mood, and support nerve health. The details matter.
Food beats supplements for getting amino acids. Grilled chicken breast, cottage cheese, and fish deliver the full package. With food, you also absorb co-factors and vitamins needed to fully use the protein. The body processes food slowly, giving a steady stream rather than the fast flood packets from many powders. I still keep powders handy after an early morning gym session, but they should not replace whole foods.
If choosing supplements, check the label. Some so-called “amino mixes” focus almost entirely on branched-chain amino acids. Those sideline options like tyrosine and serine. These oxygen-containing varieties often support neurotransmitters, which does more than just build muscle. Look for blends including a broad spectrum, and with as few additives as possible. Simpler is better. Some flavors rely on fake sweeteners, so steer clear if you can taste a chemical after-burn.
Timing remains a point people debate. Having these aminos on an empty stomach right before a workout can give a slight clarity boost. This has more to do with brain function than building muscle in the short term. Taking them after training can help muscle recovery, especially with a bit of carbohydrate to help shuttle the nutrients into hungry cells. This matches what researchers found with post-workout protein shakes: the presence of carbs speeds absorption, and the amino profile gets into action faster.
Too many get lost in the weeds of micro-managing intake. Real health, though, comes from routines you can stick with. Eating real food, keeping meals balanced, using supplements only when needed — that’s what worked for me and countless others over years of training and office work. Sometimes companies claim miracle results from special forms. There’s no shortcut around quality nutrition and consistency.
Smart supplementation makes sense for people with specific needs: vegans, older adults, high-intensity athletes, or those who can’t always get good protein. But plain truth stands — eat a varied diet, keep processed foods low, and you’ll get the amino acids, including the ones with oxygen functions, that your body craves for strong muscles, a clear mind, and lasting energy.
Every time I walk through the supplement aisle, the shelves catch my eye with products promising better energy, sharper focus, and quicker recovery. Amino acids and supplements that claim “oxygen functions” often show up in gym bags and fitness forums. Amino acids help the body build muscle, repair tissue, and keep the immune system strong. Products described as supporting “oxygen functions” tend to focus on improved circulation, endurance, or faster recovery. Mixing these products sounds appealing, but it’s not just about throwing everything together and hoping for the best.
I’ve trained for half-marathons, and I remember friends doubling up on supplements, expecting magic results. Amino acids, especially essentials like leucine, isoleucine, and valine, help muscles recover after a tough session. Supplements with “oxygen functions” usually contain things like nitric oxide boosters (think beetroot extract, L-citrulline, or arginine). These ingredients help blood vessels relax and increase blood flow, giving muscles more fuel and carrying away waste faster.
Research backs up these effects. Studies show that proper amino acid intake can speed up muscle recovery and reduce soreness. Nitric oxide boosters, found in plenty of "oxygen-focused" supplements, help runners and lifters push a bit further by delivering more oxygen during heavy exercise. Both supplement families play their part, working on different sides of the recovery process.
Plenty of trainers I’ve worked with mix these for clients chasing fitness goals. The science says that amino acids don’t block what's happening with oxygen boosters. They work on different systems: amino acids rebuild tissues, oxygen boosters open up blood vessels. Products combining amino acids with beetroot or arginine are already common in pre-workouts. No strong evidence says healthy adults face big risks if they take these together.
Still, nobody should grab every bottle on the shelf. Some combinations can go overboard. Taking huge doses of L-arginine can cause stomach troubles. Mixing multiple nitric oxide boosters hikes the risk of headaches or blood pressure drops, especially for people with underlying conditions. Taking only a few ingredients at recommended levels means fewer surprises for the body.
A registered dietitian pushed me to keep a simple rule: less is more unless you’re working with a medical pro. Checking for overlapping ingredients on labels makes a big difference. Two separate products might double the dose without making it clear on the front label. Sticking with brands that have been batch-tested or certified by groups like NSF or Informed-Sport reduces the risk of contamination or wild claims.
Looking at the bigger picture, nutrition still runs the show. Whole foods provide a balance of amino acids and the vitamins or minerals needed to process oxygen. Gym supplements can fill gaps, but meals built around lean meats, beans, vegetables, and grains help more in the long run.
Anyone thinking about mixing these products should ask why they're supplementing. Is there a real need, like a high training load or a restricted diet, or is it just the latest internet trend? For those with heart, kidney, or blood pressure issues, a doctor’s appointment comes before a supplement order. Training logs, food diaries, and open talks with health professionals make adjustments safer.
In the end, combining amino acids with oxygen-action supplements can fit into a smart routine, but only with careful attention to what goes in the body. Food, careful label reading, and honest assessment of personal fitness goals matter more than chasing the newest blend.
Walking through a health store or scrolling online, amino acids always pop up as building blocks for the body. Some, like serine and threonine, have oxygen in their side chains. These don’t just sound fancy—they play real roles. That’s why people wonder about safety, especially if taking supplements every day makes a difference. Health isn’t just about what you add, but how long you keep it going.
Amino acids with oxygen functions have groups in their structures (like hydroxyl in serine, or carboxyl in aspartic and glutamic acids) that can form important bonds inside the body. Our cells already use these for protein building, nerve function, and metabolism. Most people get them from food without any problem. The body knows what to do with them because evolution has baked them into our diets for thousands of years.
Adding more through pills or powders starts a fresh conversation. Plenty of research has looked at single doses or short-term use. Not as much on what happens over years. For example, studies show that a small boost from something like L-serine can help nerves and even fight off some rare diseases. Still, high doses over months can affect kidney function, and excess glutamic acid could bring up concerns for people with certain brain conditions.
I’ve spoken with dietitians and seen folks in gyms try protein powders loaded with these amino acids. Most tell me they feel fine, sometimes even better, especially when recovering from workouts. It’s the unknowns over the long haul that make some people nervous. Too much of a good thing can tip the scales, especially if someone already has a medical condition or takes other medications.
The gut handles most amino acids pretty smoothly. The body either uses them or gets rid of extras, usually through urine. Still, taking supplements for years without a real need can stress the kidneys or liver over time. One clinical review, published in the Journal of Nutrition, pointed out that most healthy adults can handle moderate supplementation, but children, pregnant people, or those with kidney or liver issues should stay cautious.
Nature built a check and balance into real food. Eating eggs, beans, or fish gives people amino acids in amounts the body expects. Supplements, though, can bypass that natural guardrail. Many companies do minimal testing, and the FDA only steps in if people report harm. History with other supplements shows it’s usually not a single dose, but piling on large amounts day after day that creates risk.
So much of safety comes from moderation and knowing personal health. Doctors and dietitians recommend sticking to well-tested brands, looking for certifications from groups that test for purity and strength. Regular bloodwork helps catch any trouble early, especially for those with health challenges. Food-first remains the smartest path, using supplements to fill gaps rather than as a daily habit for everyone.
Research should keep rolling, covering real humans over years, not just animals or lab tubes. Product labels need to spell out risks more clearly. That way, people know more than just a promise on a shiny package.
| Names | |
| Preferred IUPAC name | 2-Amino-3-hydroxypropanoic acid |
| Other names |
Hydroxy Amino Acids Oxo Amino Acids Amino Alcohols |
| Pronunciation | /əˈmiːnoʊ ˈæsɪdz wɪð ˈɒksɪdʒən ˈfʌŋkʃənz/ |
| Identifiers | |
| CAS Number | 9016-42-2 |
| Beilstein Reference | 4 IV 115 |
| ChEBI | CHEBI:33523 |
| ChEMBL | CHEMBL5095 |
| ChemSpider | 36691216 |
| DrugBank | DB01677 |
| ECHA InfoCard | 03-2119482327-43-0000 |
| EC Number | 1.4.-.- |
| Gmelin Reference | 42931 |
| KEGG | C00047 |
| MeSH | D-amino acids with oxygen functions |
| PubChem CID | 5697 |
| RTECS number | WV6950000 |
| UNII | D8K3JZOJ8M |
| UN number | 2811 |
| Properties | |
| Chemical formula | C2H5NO2 |
| Molar mass | 147.13 g/mol |
| Appearance | White crystals or crystalline powder |
| Odor | Characteristic |
| Density | 1.016 g/cm³ |
| Solubility in water | Soluble |
| log P | -2.5 |
| Vapor pressure | 0 mm Hg (approx) |
| Acidity (pKa) | 2.2, 9.1 |
| Basicity (pKb) | 1.8 - 10.57 |
| Magnetic susceptibility (χ) | -6.8E-6 |
| Refractive index (nD) | 1.4800 |
| Viscosity | 50 mPa.s |
| Dipole moment | 11.28 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 150.0 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -376.8 |
| Std enthalpy of combustion (ΔcH⦵298) | –968.6 kJ·mol⁻¹ |
| Pharmacology | |
| ATC code | B05BA |
| Hazards | |
| GHS labelling | GHS07, GHS08 |
| Pictograms | GHS07, GHS08 |
| Signal word | Warning |
| Hazard statements | Harmful if swallowed. Causes serious eye irritation. |
| Precautionary statements | Keep container tightly closed. Store in a cool, dry, well-ventilated place. Avoid breathing dust, fumes, gas, mist, vapors, or spray. Wash thoroughly after handling. Wear protective gloves, protective clothing, eye protection, and face protection. |
| NFPA 704 (fire diamond) | 2-1-0 |
| Autoignition temperature | Autoignition temperature: 450 °C |
| Lethal dose or concentration | LD₅₀ Oral Rat 5,000 mg/kg |
| LD50 (median dose) | 8600 mg/kg (Rat) |
| NIOSH | H0398 |
| PEL (Permissible) | PEL (Permissible Exposure Limit) for Amino Acids with Oxygen Functions: "Not Established |
| REL (Recommended) | 200 mg |
| Related compounds | |
| Related compounds |
Amino acids Amino acid esters Amino acid amides Amino acid derivatives Peptides Hydroxy acids Oxo acids Amino alcohols |
