All articles starting with S
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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.
Sulfonylurea
A sulfonylurea, plural sulfonylureas, is an oral antidiabetic drug used in type 2 diabetes that lowers blood glucose by stimulating insulin secretion from pancreatic beta cells.
Sulforaphane
Sulforaphane is an isothiocyanate compound found in broccoli and broccoli sprouts, isolated at Johns Hopkins in 1992 and known for activating the KEAP1-NRF2 cellular defense pathway.
Sulfosulfuron
Sulfosulfuron (CAS 141776-32-1) is a sulfonylurea ALS-inhibiting herbicide developed by Takeda for wheat weed control at 25-50 g ai/ha; EU-approved to 2030, highly soil-mobile, low mammalian toxicity.
Sulfotep
Sulfotep (sulfotepp, tetraethyl dithiopyrophosphate, CAS 3689-24-5) is a highly toxic organophosphate acetylcholinesterase-inhibiting insecticide/acaricide used on US greenhouse ornamentals since 1951; not EU-approved.
Sulfotransferase
Sulfotransferases (SOTs, STs, EC 2.8.2.-) are PAPS-dependent enzymes transferring a sulfuryl group to hydroxyl or amino groups of substrates, spanning cytosolic SULTs, Golgi TPSTs and CHSTs, and plant SULT, TPST and NFST subfamilies.
Sulfoxaflor
Sulfoxaflor (Isoclast) is a sulfoximine insecticide, IRAC Group 4C nicotinic acetylcholine receptor agonist, first US-registered 2013, vacated 2015, re-registered 2019; EU restricted over bee risks.
Sulfoxidation
Sulfoxidation is the chemical oxidation of a sulfide (thioether) to a sulfoxide, a named synthetic method whose catalytic asymmetric variants are used industrially to make chiral drugs such as esomeprazole.
Sulfoxide
A sulfoxide is an organosulfur compound in which a sulfur atom is bonded to two carbon substituents and one oxygen, sitting one oxidation level above sulfides and one below sulfones.
Sulfoxone
Sulfoxone (aldesulfone, Diasone sodium) is a water-soluble dapsone-derived sulfone formerly used to treat leprosy and dermatitis herpetiformis; it inhibits dihydropteroate synthase and its US product is discontinued.
Sulfoxonium ylides as carbene precursors
Sulfoxonium ylides are zwitterionic organosulfur compounds, typically bench-stable crystalline solids, that transfer carbene units under metal or photochemical catalysis as safer alternatives to diazo compounds, with wide use in C–H activation and cyclopropanation.