(4S)-4-(Phenylsulfanyl)-L-Proline stands as a distinctive synthetic amino acid derivative, drawing attention not only for its chemical structure but also for its presence in research settings and specialized chemical manufacturing. The molecule represents an alteration of L-proline through the connection of a phenylsulfanyl group at the fourth position, specifically featuring the S stereochemistry that relates to its three-dimensional orientation. Folks in the field of organic chemistry know this compound by its systematic IUPAC name, (2S,4S)-4-(phenylsulfanyl)pyrrolidine-2-carboxylic acid. This name signals its place among amino acids, but the phenylsulfanyl moiety changes both its reactivity and its applications compared to standard proline.
Looking at physical details, (4S)-4-(Phenylsulfanyl)-L-Proline commonly appears as a solid, tending toward a white or off-white powder. It can also appear as flakes, depending on synthesis and drying techniques. Some vendors offer it as crystalline pearls or larger crystalline forms, but the powder variation usually provides the easiest handling and measurement. Rarely seen as a solution or a liquid, this amino acid stays firm in solid form under standard temperature and pressure. Density falls close to typical amino acid values, hovering in the region of 1.2 g/cm³, making it straightforward to weigh out for precise lab scale reactions. Crystallinity and solubility change slightly based on how tightly the phenylsulfanyl arm packs with the proline core, affecting solubility in water and organic solvents.
Chemists studying structure notice a proline ring — a five-membered pyrrolidine — with a phenylsulfanyl substituent on the fourth carbon. The configuration sticks to the (4S) stereoisomer, which becomes crucial for certain enantioselective syntheses in pharmaceutical and medical fields. The molecular formula, C11H13NO2S, underlines the presence of one sulfur atom, connecting the aromatic ring and the pyrrolidine. This formula also cues researchers to its moderate molecular weight and its potential for both hydrogen bonding (thanks to the carboxyl and amino groups) and hydrophobic contacts (from the aromatic ring).
Industry shipment and global trading require concrete identification, and (4S)-4-(Phenylsulfanyl)-L-Proline generally carries an HS Code classed within the amino acid or heterocyclic compound categories. The Harmonized System Code for most amino acids, often 2922.50, might be adapted by region or for special sulfur-containing derivatives. Analytical standards usually demand purity over 98%, with trace impurity details available through HPLC and NMR analysis. Certificates of analysis commonly list melting point ranges around 170–175°C, a clear marker of substance consistency.
Even specialty building blocks pose risks worthy of attention. (4S)-4-(Phenylsulfanyl)-L-Proline doesn’t fall into the most acutely toxic chemicals; basic lab precautions guard against most issues. Skin contact, ingestion, and inhalation should be avoided since untested compounds can trigger irritation or allergic response. Standard hazard statements refer to potential respiratory or skin sensitization. Good practice uses nitrile gloves, well-ventilated working spaces, and eye protection to keep any accidental exposure in check. Material Safety Data Sheets emphasize safe storage away from heat or strong oxidizing agents, a rule owing more to perfectionist lab practice than strict reactivity.
(4S)-4-(Phenylsulfanyl)-L-Proline attracts research teams searching for new catalysts, peptidomimetics, or modified amino acid residues with properties distinct from natural proteinogenic molecules. Sulfur substitutions in proline frequently shift folding, recognition, or reactivity in peptides, offering new levers in drug design and catalyst construction. Raw material sourcing often starts with commercially available L-proline, which is then subjected to targeted derivatization steps introducing the phenylsulfanyl group via thiolation and arylation chemistry. Efficient synthesis and reliable access to the right stereoisomer makes this building block available for forward-looking applications, though prices can rise with scale or chirality demand.
Any lab or production site storing (4S)-4-(Phenylsulfanyl)-L-Proline commits to secure, dry containers, often in amber glass or tightly sealed polyethylene to block out excess humidity and light. Spills and cleanup do not pose reactive dangers, but regular powdered-proline dust causes minor irritation if not cleaned up promptly. Disposal usually proceeds in line with non-halogenated organic waste protocols, with collected waste containers sent to accredited chemical waste disposal services. Workers get trained in hazard recognition and quick isolation of any container leaks or spills, anchoring personal safety in routine vigilance.
Maintaining product quality and authenticity in specialty chemicals often ties to consistency in synthesis, clear labeling, and robust analytical documentation. Labs seeking reproducible results rely on suppliers providing batch-specific spectra and detailed certificates of analysis. Verifying isomeric purity — crucial with synthetic amino acids — needs vigilant attention using tools like chiral HPLC and NMR. Sourcing raw materials responsibly can address environmental or ethical worries, especially as chemical manufacturing faces scrutiny over waste management and carbon footprint. A commitment to greener synthetic routes and transparent provenance stands to benefit both producers and labs in the long run.
Years spent handling amino acid derivatives hammered home the importance of knowing each substance beyond a simple label. Even minor tweaks, like the phenylsulfanyl group here, shift how an amino acid acts, how it feels to work with, and how it influences larger assemblies in peptides or catalysts. Running reactions with (4S)-4-(Phenylsulfanyl)-L-Proline brings its own practical quirks: a tendency to form cohesive lumps if humidity creeps in, a faint odor from the sulfur group, and slight stickiness compared to vanilla proline. Careful technique goes a long way in maintaining purity through each transfer and blending session, preventing cross-contamination that could wreck weeks of work.
Experienced chemists find (4S)-4-(Phenylsulfanyl)-L-Proline to be a niche but highly useful addition to the roster of modified amino acids. Its value grows in hands willing to match attention to detail with creative synthetic thinking. Keeping materials safe, clean, and traceable relies on clear communication — between suppliers, researchers, and regulatory agencies — and a shared commitment to technical rigor. Supply chain transparency plus sustainable synthesis signals progress in chemical manufacturing, setting new benchmarks for the field.
