All articles A–Z
519,064 articles
Sulfentrazone
Sulfentrazone (Authority, Dismiss) is an aryl triazolinone, group 14 PPO-inhibiting herbicide first US-registered in 1997, used preemergence in soybeans and turf, highly soil-mobile with a 1.5-year aerobic half-life.
Sulfhydryl oxidase
Sulfhydryl oxidase (QSOX, Quiescin-sulfhydryl oxidase; EC 1.8.3.-) is a FAD-dependent enzyme family oxidizing thiols to disulfides with oxygen, producing H2O2, in secretory-pathway protein folding.
Sulfide
Sulfide, also called sulfide, names two classes of sulfur chemistry: organic compounds of the structure RSR, once called thioethers, and inorganic salts derived from hydrogen sulfide.
Sulfide minerals
Sulfide minerals are minerals in which sulfur combines as an anion with metal or semi-metal cations, including pyrite and galena; they supply most copper, lead, zinc, and nickel, but their oxidation causes acid mine drainage.
Sulfide solid electrolyte
A sulfide solid electrolyte is a sulfur-based ceramic that conducts lithium or sodium ions while blocking electrons, serving as the ion-transporting separator in all-solid-state batteries.
Sulfide solid-state battery
Solid-state lithium batteries with sulfide electrolytes are rechargeable batteries in which the flammable liquid electrolyte is replaced by a sulfide solid, such as LGPS or Li₆PS₅Cl, matching liquid electrolytes in ionic conductivity and enabling lithium-metal anodes.
Sulfide stress cracking
Sulfide stress cracking (SSC) is a form of hydrogen embrittlement that cracks steel under tensile stress in wet hydrogen sulfide environments, mainly in sour oil and gas service.
Sulfinpyrazone
Sulfinpyrazone (Anturane) is an oral uricosuric drug, a phenylbutazone analog that lowers serum urate in chronic gout by blocking uric acid reabsorption in the kidney.
Sulfiredoxin
Sulfiredoxin (Srx, human gene SRXN1) is an ATP- and Mg2+-dependent enzyme that repairs hyperoxidized typical 2-Cys peroxiredoxins by reducing active-site cysteine sulfinic acid, restoring peroxidase activity; discovered in yeast in 2003, regulated by Nrf2 and AP-1, implicated in cancer, Parkinson's disease, and liver disease.
Sulfisomidine
Sulfisomidine (sulfaisodimidine, Elkosin) is a short-acting sulfonamide antibacterial, CAS 515-64-0, formula C12H14N4O2S, ATC J01EB01, studied for urinary tract infections in the 1950s and now withdrawn.
Sulfisoxazole
Sulfisoxazole is a synthetic sulfonamide antibiotic that stops bacterial growth, available in the United States only combined with erythromycin, prescribed mainly for bacterial ear infections in children.
Sulfite
Sulfite, also known as the sulfite ion, is the SO₃²⁻ anion whose salts and related sulfur dioxide compounds are widely used as food preservatives and reducing agents.
Sulfite activation
Sulfite activation is a water-treatment method in which an activator, such as UV light, a transition metal, or carbon, converts sulfite into radicals that degrade organic pollutants.
Sulfite ester
A sulfite ester, also called an organosulfite or alkyl sulfite, is the diester of sulfurous acid, RO–S(=O)–OR, including cyclic members like ethylene sulfite used as lithium-ion battery electrolyte additives.
Sulfite oxidase
Sulfite oxidase (SOX, SUOX, EC 1.8.3.1) is a molybdenum cofactor and heme enzyme in the mitochondrial intermembrane space that oxidizes sulfite to sulfate, the terminal step of sulfur amino acid catabolism; its loss causes severe neonatal sulfite intoxication.
Sulfite process
The sulfite process is a chemical pulping method that dissolves lignin from wood chips using sulfur dioxide and a bisulfite base, freeing cellulose fibers for papermaking.
Sulfolane
Sulfolane, also known as tetramethylene sulfone, is an organosulfur compound used as a high-boiling polar solvent in aromatics extraction and gas sweetening, later linked to groundwater contamination in North Pole, Alaska.
Sulfolene
Sulfolene (butadiene sulfone) is an organosulfur compound, a five-membered cyclic sulfone formed from butadiene and sulfur dioxide, best known as a stable crystalline surrogate for gaseous 1,3-butadiene in Diels–Alder reactions.
Sulfolobales
Sulfolobales is an order of thermoacidophilic archaea found in acidic hot springs worldwide, growing at 65 to 90°C and pH around 2, used in biomining metals from ores.
Sulfolobus
Sulfolobus is a genus of thermoacidophilic archaea from volcanic hot springs; type species S. acidocaldarius (Brock, 1972, Yellowstone) grows near 75°C, pH 2–3, and is the leading genetic model of the Thermoproteota.
Sulfolobus acidocaldarius
Sulfolobus acidocaldarius (DSM 639) is a thermoacidophilic archaeon isolated by Thomas Brock from Yellowstone in 1972, growing optimally at ~75°C and pH 2–3, with a 2.23 Mbp genome and the MW001 genetic toolbox making it a leading archaeal model organism.
Sulfolobus metallicus
Sulfolobus metallicus is a thermoacidophilic archaeon, isolated from an Icelandic solfataric field in 1991, that oxidizes iron and sulfur and dominates bioleaching operations at about 70 °C.
Sulfolobus spindle-shape virus 1 F-112 protein-like
F-112 protein-like (Pfam PF09645, UniProt P20220) is the winged-helix DNA-binding protein F112 of Sulfolobus spindle-shape virus 1, a 112-residue monomer with an intrachain disulfide bond, PDB 2VQC, likely a transcription regulator.
Sulfonamide (medicine)
Sulfonamide (medicine): sulfa drugs, the oldest synthetic antibacterial class, PABA analogues inhibiting bacterial DHPS; includes sulfamethoxazole, TMP-SMX, sulfadoxine-pyrimethamine; distinguished from non-antibiotic sulfonamides like furosemide and celecoxib, which lack cross-reactivity.
Sulfonate
A sulfonate is a salt or ester of a sulfonic acid; its esters, such as tosylates, mesylates, and triflates, rank among the best leaving groups in organic synthesis.
Sulfonation
Sulfonation is a chemical reaction that introduces a sulfonic acid group, –SO₃H, onto an organic molecule, most often by attack of sulfur trioxide on an aromatic ring.
Sulfone
A sulfone is an organosulfur compound of structure RS(=O)₂R′, in which a sulfur atom bonded to two carbons also carries two oxygens; it appears in drugs and polymers.
Sulfonic acid
Sulfonic acid, also written sulphonic acid, is a strong organosulfur acid of formula R−S(=O)₂−OH; its sulfonate salts are used in detergents, ion-exchange resins, and proton-exchange fuel-cell membranes such as Nafion.
Sulfonium salt
A sulfonium salt is an ionic compound whose cation is a trivalent sulfur bonded to three organic groups, R3S+, with an anion such as chloride.
Sulfonium salt cross-coupling
Sulfonium salt cross-coupling uses organosulfonium salts, most often arylsulfonium salts, as electrophilic coupling partners in transition-metal-catalyzed, photochemical, and metal-free carbon-carbon and carbon-heteroatom bond-forming reactions, replacing the aryl halide C-halogen bond.