ChemicalName stringlengths 3 104 | Definition stringlengths 12 791 |
|---|---|
spiro compounds | Cyclic compounds that include two rings which share a single atom (usually a carbon). The simplest example of this type of compound is Spiro[2.2]pentane, which looks like a bow tie. |
spironolactone | A potassium sparing diuretic that acts by antagonism of aldosterone in the distal renal tubules. It is used mainly in the treatment of refractory edema in patients with congestive heart failure, nephrotic syndrome, or hepatic cirrhosis. Its effects on the endocrine system are utilized in the treatments of hirsutism and acne but they can lead to adverse effects. (From Martindale, The Extra Pharmacopoeia, 30th ed, p827) |
spirooxindoles | Compounds that consist of cycloalkyl or heterocyclic moieties fused at the C-3 position of an oxindole. Their applications include use as scaffolds in drug design processes. |
spirostans | Cholestane derivatives containing a fused lactone ring at the 16,17-position and a spiroglycosidic linkage at C-22. Members include sarsaponin, DIOSGENIN and yamogenin. |
sporidesmins | A group of related mycotoxins produced by the pasture fungus Pithomyces chartarum (formerly Sporidesmium bakeri); causes liver damage and facial eczema in cattle and sheep. |
squalene | A natural 30-carbon triterpene. |
srs-a | A group of LEUKOTRIENES; (LTC4; LTD4; and LTE4) that is the major mediator of BRONCHOCONSTRICTION; HYPERSENSITIVITY; and other allergic reactions. Earlier studies described a slow-reacting substance of ANAPHYLAXIS released from lung by cobra venom or after anaphylactic shock. The relationship between SRS-A leukotrienes was established by UV which showed the presence of the conjugated triene. (From Merck Index, 11th ed) |
ss-b antigen | Nuclear autoantigens implicated in nascent RNA protection. It is a target of AUTOANTIBODIES in patients with SJOGREN'S SYNDROME. |
stage-specific embryonic antigens | Cell-surface molecules that exhibit lineage-restricted patterns of expression during EMBRYONIC DEVELOPMENT. The antigens are useful markers in the identification of EMBRYONIC STEM CELLS. |
stainless steel | Stainless steel. A steel containing Ni, Cr, or both. It does not tarnish on exposure and is used in corrosive environments. (Grant & Hack's Chemical Dictionary, 5th ed) |
stanozolol | A synthetic steroid that has anabolic and androgenic properties. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1194) |
staphylococcal protein a | A protein present in the cell wall of most Staphylococcus aureus strains. The protein selectively binds to the Fc region of human normal and myeloma-derived IMMUNOGLOBULIN G. It elicits antibody activity and may cause hypersensitivity reactions due to histamine release; has also been used as cell surface antigen marker and in the clinical assessment of B lymphocyte function. |
starch | Any of a group of polysaccharides of the general formula (C6-H10-O5)n, composed of a long-chain polymer of glucose in the form of amylose and amylopectin. It is the chief storage form of energy reserve (carbohydrates) in plants. |
staurosporine | An indolocarbazole that is a potent PROTEIN KINASE C inhibitor which enhances cAMP-mediated responses in human neuroblastoma cells. (Biochem Biophys Res Commun 1995;214(3):1114-20) |
stavudine | A dideoxynucleoside analog that inhibits reverse transcriptase and has in vitro activity against HIV. |
steam | Water in its gaseous state. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed) |
stearates | Salts and esters of the 18-carbon saturated, monocarboxylic acid--stearic acid. |
stearic acids | A group of compounds that are derivatives of octadecanoic acid which is one of the most abundant fatty acids found in animal lipids. (Stedman, 25th ed) |
steel | A tough, malleable, iron-based alloy containing up to, but no more than, two percent carbon and often other metals. It is used in medicine and dentistry in implants and instrumentation. |
stem cell factor | A hematopoietic growth factor and the ligand of the cell surface c-kit protein (PROTO-ONCOGENE PROTEINS C-KIT). It is expressed during embryogenesis and is a growth factor for a number of cell types including the MAST CELLS and the MELANOCYTES in addition to the HEMATOPOIETIC STEM CELLS. |
stemona alkaloids | Structurally related ALKALOIDS derived from the plants of the monocotyledonous family STEMONACEAE, characterized by the presence of a pyrrolo(1,2-a)azepine or a pyrido(1,2-a)azepine nucleus. |
sterigmatocystin | A carcinogenic mycotoxin produced in high yields by strains of the common molds, Aspergillus versicolor, A. nidulans, and an unidentified species of Bipolaris. It causes necrosis of the liver and kidney and has an inhibitory effect on orotic acid incorporation into nuclear RNA. |
steroids | A group of polycyclic compounds closely related biochemically to TERPENES. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (STEROLS), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus. (From Hawley's Condensed Chemical Dictionary, 11th ed) |
steroids, brominated | Steroids which are substituted with one or more bromine atoms in any position. |
steroids, chlorinated | Steroids which are substituted with one or more chlorine atoms in any position. |
steroids, fluorinated | Steroids which are substituted with one or more fluorine atoms in any position. |
steroids, heterocyclic | Steroidal compounds in which one or more carbon atoms in the steroid ring system have been substituted with non-carbon atoms. |
steroid synthesis inhibitors | Compounds that bind to and inhibit enzymes involved in the synthesis of STEROIDS. |
sterols | Steroids with a hydroxyl group at C-3 and most of the skeleton of cholestane. Additional carbon atoms may be present in the side chain. (IUPAC Steroid Nomenclature, 1987) |
stilbamidines | STILBENES with AMIDINES attached. |
stilbenes | Organic compounds that contain 1,2-diphenylethylene as a functional group. |
stilbestrols | Stilbene derivatives the contain one or more hydroxyl groups attached to the benzene ring structures. |
stimuli responsive polymers | Polymeric materials designed to change properties in response to a stimulus. |
stratospheric ozone | Ozone in the Earth's stratosphere. It is produced continuously by the action of solar ULTRAVIOLET RAYS on oxygen in the stratosphere. The stratospheric ozone (especially at the ozone layer) blocks much of the solar UV radiation of wavelengths of 320 nanometers or less from being transmitted to lower ATMOSPHERE of the Earth. |
streptococcal vaccines | Vaccines or candidate vaccines used to prevent STREPTOCOCCAL INFECTIONS. |
streptogramin a | A specific streptogramin group A antibiotic produced by Streptomyces graminofaciens and other bacteria. |
streptogramin b | A specific streptogramin group B antibiotic produced by Streptomyces graminofaciens and other bacteria. |
streptogramin group a | A structural subclass of streptogramins that includes molecules containing unsaturated macrocyclic lactones with approximate molecular weight of 500 KDa. |
streptogramin group b | A structural subclass of streptogramins. They are cyclic hexadepsipeptides with approximate molecular weight of 800 that contain a characteristic 3-hydroxy picolinoyl exocyclic component. |
streptogramins | A class of natural cyclic peptide antibiotics produced by certain subspecies of STREPTOMYCES. They include two structurally unrelated components, STREPTOGRAMIN GROUP A and STREPTOGRAMIN GROUP B, which generally act synergistically to inhibit bacterial growth. |
streptolysins | Exotoxins produced by certain strains of streptococci, particularly those of group A (STREPTOCOCCUS PYOGENES), that cause HEMOLYSIS. |
streptomycin | An antibiotic produced by the soil actinomycete Streptomyces griseus. It acts by inhibiting the initiation and elongation processes during protein synthesis. |
streptonigrin | Complex cytotoxic antibiotic obtained from Streptomyces flocculus or S. rufochronmogenus. It is used in advanced carcinoma and causes leukopenia. |
streptothricins | A group of antibiotic aminoglycosides differing only in the number of repeating residues in the peptide side chain. They are produced by Streptomyces and Actinomyces and may have broad spectrum antimicrobial and some antiviral properties. |
streptovaricin | A complex of ansamycin antibiotics consisting of streptovaricins A, B, C, D, E, F, G, J, and K of which streptovaricin C is the major component. (From Merck Index, 11th ed) |
streptozocin | An antibiotic that is produced by Stretomyces achromogenes. It is used as an antineoplastic agent and to induce diabetes in experimental animals. |
strobilurins | Benzene or pyrimidine derivatives of methacrylic acid that block the Qo site of CYTOCHROME B. They are widely used as agricultural fungicides. |
strontium | An element of the alkaline earth family of metals. It has the atomic symbol Sr, atomic number 38, and atomic weight 87.62. |
strontium isotopes | Stable strontium atoms that have the same atomic number as the element strontium, but differ in the atomic weight. Sr-84, 86, 87, and 88 are the stable strontium isotopes. |
strontium radioisotopes | Unstable isotopes of strontium that decay or disintegrate spontaneously emitting radiation. Sr 80-83, 85, and 89-95 are radioactive strontium isotopes. |
strophanthidin | 3 beta,5,14-Trihydroxy-19-oxo-5 beta-card-20(22)-enolide. The aglycone cardioactive agent isolated from Strophanthus Kombe, S. gratus and other species; it is a very toxic material formerly used as digitalis. Synonyms: Apocymarin; Corchorin; Cynotoxin; Corchorgenin. |
strophanthins | A number of different cardioactive glycosides obtained from Strophanthus species. OUABAIN is from S. gratus and CYMARINE from S. kombe. They are used like the digitalis glycosides. |
struvite | The mineral magnesium ammonium phosphate with the formula NH4MgPO4. It is associated with urea-splitting organisms in a high magnesium, high phosphate, alkaline environment. Accumulation of crystallized struvite is found in the urinary tract as struvite CALCULI and as scale on sewage system equipment and wastewater pipes. |
strychnine | An alkaloid found in the seeds of STRYCHNOS NUX-VOMICA. It is a competitive antagonist at glycine receptors and thus a convulsant. It has been used as an analeptic, in the treatment of nonketotic hyperglycinemia and sleep apnea, and as a rat poison. |
styrene | A colorless, toxic liquid with a strong aromatic odor. It is used to make rubbers, polymers and copolymers, and polystyrene plastics. |
styrenes | Derivatives and polymers of styrene. They are used in the manufacturing of synthetic rubber, plastics, and resins. Some of the polymers form the skeletal structures for ion exchange resin beads. |
substance p | An eleven-amino acid neurotransmitter that appears in both the central and peripheral nervous systems. It is involved in transmission of PAIN, causes rapid contractions of the gastrointestinal smooth muscle, and modulates inflammatory and immune responses. |
succimer | A mercaptodicarboxylic acid used as an antidote to heavy metal poisoning because it forms strong chelates with them. |
succinates | Derivatives of SUCCINIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a 1,4-carboxy terminated aliphatic structure. |
succinic acid | A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawley's Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851) |
succinic anhydrides | A subclass of anhydrides with the general structure of dihydrofurandione. They can be substituted on any carbon atom. They modify and inhibit proteins and enzymes and are used in the acylation of amino- and hydroxyl groups. |
succinimides | A subclass of IMIDES with the general structure of pyrrolidinedione. They are prepared by the distillation of ammonium succinate. They are sweet-tasting compounds that are used as chemical intermediates and plant growth stimulants. |
succinylcholine | A quaternary skeletal muscle relaxant usually used in the form of its bromide, chloride, or iodide. It is a depolarizing relaxant, acting in about 30 seconds and with a duration of effect averaging three to five minutes. Succinylcholine is used in surgical, anesthetic, and other procedures in which a brief period of muscle relaxation is called for. |
sucralfate | A basic aluminum complex of sulfated sucrose. |
sucrose | A nonreducing disaccharide composed of GLUCOSE and FRUCTOSE linked via their anomeric carbons. It is obtained commercially from SUGARCANE, sugar beet (BETA VULGARIS), and other plants and used extensively as a food and a sweetener. |
sufentanil | An opioid analgesic that is used as an adjunct in anesthesia, in balanced anesthesia, and as a primary anesthetic agent. |
sugammadex | A gamma-cyclodextrin that functions as a reversal agent for the neuromuscular blocker ROCURONIUM BROMIDE. |
sugar acids | MONOSACCHARIDES and other sugars that contain one or more carboxylic acid moieties. |
sugar alcohols | Polyhydric alcohols having no more than one hydroxy group attached to each carbon atom. They are formed by the reduction of the carbonyl group of a sugar to a hydroxyl group. (From Dorland, 28th ed) |
sugars | Short chain carbohydrate molecules that have hydroxyl groups attached to each carbon atom unit with the exception of one carbon that has a doubly-bond aldehyde or ketone oxygen. Cyclical sugar molecules are formed when the aldehyde or ketone groups respectively form a hemiacetal or hemiketal bond with one of the hydroxyl carbons. The three dimensional structure of the sugar molecule occurs in a vast array of biological and synthetic classes of specialized compounds including AMINO SUGARS; CARBASUGARS; DEOXY SUGARS; SUGAR ACIDS; SUGAR ALCOHOLS; and SUGAR PHOSPHATES. |
sulbactam | A beta-lactamase inhibitor with very weak antibacterial action. The compound prevents antibiotic destruction of beta-lactam antibiotics by inhibiting beta-lactamases, thus extending their spectrum activity. Combinations of sulbactam with beta-lactam antibiotics have been used successfully for the therapy of infections caused by organisms resistant to the antibiotic alone. |
sulbenicillin | Semisynthetic penicillin-type antibiotic. |
sulfacetamide | An anti-bacterial agent that is used topically to treat skin infections and orally for urinary tract infections. |
sulfachlorpyridazine | A sulfonamide antimicrobial used for urinary tract infections and in veterinary medicine. |
sulfadiazine | One of the short-acting SULFONAMIDES used in combination with PYRIMETHAMINE to treat toxoplasmosis in patients with acquired immunodeficiency syndrome and in newborns with congenital infections. |
sulfadimethoxine | A sulfanilamide that is used as an anti-infective agent. |
sulfadoxine | A long acting sulfonamide that is used, usually in combination with other drugs, for respiratory, urinary tract, and malarial infections. |
sulfaguanidine | A sulfanilamide antimicrobial agent that is used to treat enteric infections. |
sulfalene | Long-acting plasma-bound sulfonamide used for respiratory and urinary tract infections and also for malaria. |
sulfamerazine | A sulfanilamide that is used as an antibacterial agent. |
sulfameter | Long acting sulfonamide used in leprosy, urinary, and respiratory tract infections. |
sulfamethazine | A sulfanilamide anti-infective agent. It has a spectrum of antimicrobial action similar to other sulfonamides. |
sulfamethizole | A sulfathiazole antibacterial agent. |
sulfamethoxazole | A bacteriostatic antibacterial agent that interferes with folic acid synthesis in susceptible bacteria. Its broad spectrum of activity has been limited by the development of resistance. (From Martindale, The Extra Pharmacopoeia, 30th ed, p208) |
sulfamethoxypyridazine | A sulfanilamide antibacterial agent. |
sulfamonomethoxine | Long acting sulfonamide antibacterial agent. |
sulfamoxole | A sulfanilamide antibacterial agent. |
sulfanilamide | A short-acting sulfonamide used as an anti-infective agent. It has lower anti-bacterial activity than SULFAMETHOXAZOLE. |
sulfanilamides | Compounds based on 4-aminobenzenesulfonamide. The '-anil-' part of the name refers to aniline. |
sulfanilic acids | Aminobenzenesulfonic acids. Organic acids that are used in the manufacture of dyes and organic chemicals and as reagents. |
sulfaphenazole | A sulfonilamide anti-infective agent. |
sulfapyridine | Antibacterial, potentially toxic, used to treat certain skin diseases. |
sulfaquinoxaline | An antiprotozoal agent used to combat coccidial infections of swine, cattle, fowl, and other veterinary animals. Also used in controlling outbreaks of fowl typhoid and fowl cholera and in treatment of infectious enteritis. |
sulfasalazine | A drug that is used in the management of inflammatory bowel diseases. Its activity is generally considered to lie in its metabolic breakdown product, 5-aminosalicylic acid (see MESALAMINE) released in the colon. (From Martindale, The Extra Pharmacopoeia, 30th ed, p907) |
sulfates | Inorganic salts of sulfuric acid. |
sulfathiazole | A sulfathiazole compound that is used as a short-acting anti-infective agent. It is no longer commonly used systemically due to its toxicity, but may still be applied topically in combination with other drugs for the treatment of vaginal and skin infections, and is still used in veterinary medicine. |
sulfathiazoles | Sulfanilamides consisting of a 4-aminobenzenesulfonamido group at the 2-position of 1,3-thiazole. They are often used as ANTI-INFECTIVE AGENTS. |
sulfenic acids | Oxy acids of sulfur with the general formula RSOH, where R is an alkyl or aryl group such as CH3. They are often encountered as esters and halides. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) |
sulfhydryl compounds | Compounds containing the -SH radical. |
sulfides | Chemical groups containing the covalent sulfur bonds -S-. The sulfur atom can be bound to inorganic or organic moieties. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.