Building Blocks
Subcategorias de "Building Blocks"
- Ácidos Borónicos e Derivados de Ácido Borónico(5.786 produtos)
- Building Blocks Quirais(1.246 produtos)
- Building Blocks Hidrocarbonetos(6.107 produtos)
- Building Blocks orgânicos(61.079 produtos)
Foram encontrados 205461 produtos de "Building Blocks"
Methyl 2-(2-chloropyrimidin-4-yl)acetate
CAS:Versatile small molecule scaffold
Fórmula:C7H7ClN2O2Pureza:Min. 95%Peso molecular:186.59 g/mol2,7-Naphthyridin-1(2H)-one
CAS:Cabozantinib is a small molecule that is the first to target VEGFR-2, which is a receptor tyrosine kinase involved in the development of fibrosis. Cabozantinib inhibits the activity of VEGFR-2 by binding to its ATP-binding site and blocking the phosphorylation of downstream signaling pathways. Cabozantinib has been shown to have antifibrotic properties in both preclinical and clinical models. The drug candidate has been shown to reduce kidney fibrosis in animal models. The standard dose for cabozantinib was found to be 5 mg/kg, with a maximum tolerated dose of 20 mg/kg. In vitro studies have indicated that cabozantinib binds with high affinity to the ATP-binding pocket of VEGFR-2, exhibiting competitive inhibition against other kinases such as PDGFR-beta and cKit, as well as diaryliodonium (a specific inhibitor). Caboz
Fórmula:C8H6N2OPureza:Min. 95%Peso molecular:146.14 g/mol8-Bromo-2-methylimidazo[1,2-a]pyridine
CAS:Versatile small molecule scaffold
Fórmula:C8H7N2BrPureza:Min. 95%Peso molecular:211.05 g/mol7-bromo-3-iodoimidazo[1,2-a]pyridine
CAS:Versatile small molecule scaffold
Fórmula:C7H4BrIN2Pureza:Min. 95%Peso molecular:322.9 g/mol2-(2-Chloro-4-nitrophenyl)acetic acid
CAS:Versatile small molecule scaffold
Fórmula:C8H6ClNO4Pureza:Min. 95%Peso molecular:215.59 g/mol4-Bromo-2-ethyliodobenzene
CAS:Versatile small molecule scaffold
Fórmula:C8H8BrIPureza:Min. 95%Peso molecular:310.96 g/mol5-(3-Hydroxyphenyl)-1H-pyrazole-3-carboxylic acid
CAS:Versatile small molecule scaffold
Fórmula:C10H8N2O3Pureza:Min. 95%Peso molecular:204.18 g/molEthyl 4-methoxy-3-oxobutanoate
CAS:Versatile small molecule scaffold
Fórmula:C7H12O4Pureza:Min. 95%Peso molecular:160.17 g/molDiethyl Acetylphosphonate
CAS:Diethyl Acetylphosphonate is a synthetic chemical that is used in the production of ethyl esters, which are used as intermediates for the production of epoxides. It has shown to be a bidentate ligand and reacts with primary amines. Diethyl Acetylphosphonate can be made by reacting phosphorus pentachloride with ethyl acetate and hydrochloric acid. The reaction mechanism is similar to that of other organophosphorus compounds, in which a phosphine oxide intermediate reacts with an organic halide. Diethyl Acetylphosphonate has shown to be effective in detergent compositions and triethyl orthoformate, as well as alkanoic acid.
Fórmula:C6H13O4PPureza:Min. 95%Peso molecular:180.14 g/mol3-(iodomethyl)oxetane
CAS:Versatile small molecule scaffold
Fórmula:C4H7IOPureza:Min. 95%Peso molecular:198 g/mol2,2-Paracyclophane
CAS:2,2-Paracyclophane is a high-sensitivity c-reactive protein (hsCRP) that has been isolated from the fungus Cryptococcus neoformans. This compound has shown to have anti-cancer properties in animal studies. 2,2-Paracyclophane binds to fatty acids and is soluble in water, which may be due to its hydrogen bonding with the hydroxyl group at C1. The crystal structure of this compound reveals that it has a cyclohexane ring and two fatty acids. The thermal expansion coefficient of this molecule is also high, which suggests that it may be suitable for use as a solid lubricant.
Fórmula:C16H16Pureza:Min. 98.5 Area-%Cor e Forma:White PowderPeso molecular:208.3 g/molPhentolamine methanesulfonate
CAS:Phentolamine is a synthetic mesylate that is used as an antihypertensive agent, and for the treatment of Raynaud's syndrome and pheochromocytoma. Phentolamine is also used to prevent frostbite and to treat various types of shock. Phentolamine blocks alpha-2-adrenergic receptors, thereby decreasing sympathetic nerve impulses to the heart, blood vessels, kidneys, and other organs. This drug also acts as a histamine antagonist by blocking H1-receptors on vascular smooth muscle cells. Phentolamine has been shown to have no significant effects on 5-hydroxytryptamine (5HT) release in vitro or in vivo.
Fórmula:C18H23N3O4SPureza:Min. 95%Cor e Forma:White PowderPeso molecular:377.46 g/molSHR 0302
CAS:Please enquire for more information about SHR 0302 including the price, delivery time and more detailed product information at the technical inquiry form on this page
Fórmula:C18H22N8O2SPureza:Min. 95%Peso molecular:414.49 g/molRef: 3D-FS182635
Produto descontinuado6-fluoroquinoline-8-carboxylicacid
CAS:Versatile small molecule scaffold
Fórmula:C10H6FNO2Pureza:Min. 95%Peso molecular:191.16 g/moltert-Butyl (2,2-difluoro-3-hydroxypropyl)carbamate
CAS:Versatile small molecule scaffoldFórmula:C10H13NO4Pureza:Min. 95%Peso molecular:211.21 g/molMethyl 1-methylnaphthalene-2-carboxylate
CAS:Versatile small molecule scaffold
Fórmula:C13H12O2Pureza:Min. 95%Peso molecular:200.23 g/mol(R)-4-N-Boc-2-hydroxymethyl-piperazine
CAS:Please enquire for more information about (R)-4-N-Boc-2-hydroxymethyl-piperazine including the price, delivery time and more detailed product information at the technical inquiry form on this page
Fórmula:C10H20N2O3Pureza:Min. 95%Peso molecular:216.28 g/mol3-Cyano-2-methylphenylboronic acid
CAS:3-Cyano-2-methylphenylboronic acid is a high quality compound that can be used as a reagent, intermediate, or building block in the synthesis of complex compounds. This chemical is also useful as a speciality chemical and research chemical. 3-Cyano-2-methylphenylboronic acid has versatile uses in organic synthesis due to its versatility in reactions and building blocks.
Fórmula:C8H8BNO2Pureza:Min. 95%Cor e Forma:PowderPeso molecular:160.97 g/mol5-Bromo-2-iodopyridine
CAS:5-Bromo-2-iodopyridine is an antibiotic that is used to treat bacterial infections. It has been shown to inhibit the growth of bacteria by binding to the 50S ribosomal subunit. This drug also has a toxic effect on respiratory system cells, which may be due to its ability to induce apoptosis. 5-Bromo-2-iodopyridine interacts with DNA in a triazine ring and inhibits bacterial growth by inhibiting protein synthesis. The drug binds to the 50S ribosomal subunit at a site that is different from that of rifampin and other antibiotics. The reaction is catalyzed by palladium at high temperatures and takes place in organic solvents such as chloroform or benzene. This synthetic process can be made more efficient by using inexpensive starting materials, such as bromine, iodine, and acetone, rather than expensive starting materials like platinum or gold salts.
Fórmula:C5H3BrINPureza:Min. 95%Cor e Forma:Slightly Yellow PowderPeso molecular:283.89 g/moltrans,trans-1,4-Diphenyl-1,3-butadiene
CAS:Used in the preparation of metal-diene reagents (e.g. for carbocyclization)
Fórmula:C16H14Pureza:Min. 95%Peso molecular:206.28 g/molMethyl 4-chlorobenzenesulfonate
CAS:Versatile small molecule scaffold
Fórmula:C7H7ClO3SPureza:Min. 95%Peso molecular:206.65 g/molInosine 5'-monophosphate disodium hydrate
CAS:Please enquire for more information about Inosine 5'-monophosphate disodium hydrate including the price, delivery time and more detailed product information at the technical inquiry form on this page
Fórmula:C10H13N4O8P•Na2•(H2O)xPureza:Min. 95%Ref: 3D-FI183272
Produto descontinuado6-Bromo-3-fluoropyridine-2-carbonitrile
CAS:Versatile small molecule scaffoldFórmula:C6H2N2FBrPureza:Min. 95%Peso molecular:200.99 g/mol1H,1H,7H-Dodecafluoroheptanol
CAS:1H,1H,7H-Dodecafluoroheptanol is a perfluorinated compound. It has been shown to be an efficient scavenger of reactive oxygen species (ROS) and to have a protective effect on collagen. The reaction mechanism of 1H,1H,7H-dodecafluoroheptanol is not fully understood. However, it has been shown that the chloride ion plays a key role in the formation of this product from 1H,1H,7F-dodecafluoroheptane. The reaction vessel used in this synthesis is critical because it must be anhydrous to prevent the formation of 1HF3OCl. Magnetic resonance spectroscopy has been used to study the chemical structures of this compound.
Fórmula:C7H4F12OPureza:Min. 95%Cor e Forma:Colorless PowderPeso molecular:332.09 g/molRef: 3D-FD37544
Produto descontinuado4-Bromo-4-methyltetrahydropyran
CAS:Versatile small molecule scaffold
Fórmula:C6H11BrOPureza:Min. 95%Peso molecular:179.06 g/mol(-)-Corey lactone diol
CAS:(-)-Corey lactone diol is a synthetic compound that is soluble in organic solvents. It is used for the synthesis of carbocyclic nucleosides, which are analogs of pyrimidine nucleosides. (-)-Corey lactone diol has been shown to inhibit cholesterol synthesis and the synthesis of alkene. (-)-Corey lactone diol also shows anti-inflammatory properties, which may be due to its inhibition of prostaglandin synthesis.
Fórmula:C8H12O4Pureza:Min. 95%Peso molecular:172.18 g/mol2-Furanamine hydrochloride
CAS:Please enquire for more information about 2-Furanamine hydrochloride including the price, delivery time and more detailed product information at the technical inquiry form on this page
Fórmula:C4H5NO•HClPureza:Min. 95%Cor e Forma:PowderPeso molecular:119.55 g/molRef: 3D-FF183657
Produto descontinuado4-Bromopyridine hydrochloride
CAS:4-Bromopyridine HCl is a chemical compound with the molecular formula C6H5BrN. It is an aromatic heterocycle and is used in organic synthesis as a coupling partner in cross-coupling reactions. The bromine atom of 4-bromopyridine is replaced by chloride, resulting in 4-chloropyridine. The chlorination reaction can be conducted using either hydrochloric acid or thionyl chloride. This process can be done on an industrial scale and the chlorinated product has been used in the manufacture of pharmaceuticals, dyes, and pesticides. The reaction mechanism for this substitution reaction involves a nucleophilic attack by chlorine on the pyridine ring at carbon atom 2 followed by displacement of hydrogen from the adjacent position on nitrogen atom 3. Acylation reactions are oxidation processes that involve conversion of carboxylic acids to acyl halides or acyl chlorides through treatment with acidified halogenating agents such
Fórmula:C5H4BrN•HClPureza:Min. 95%Cor e Forma:White PowderPeso molecular:194.46 g/mol2,4-Dichloro-6-(propan-2-yl)pyrimidine
CAS:Versatile small molecule scaffold
Fórmula:C7H8Cl2N2Pureza:Min. 95%Peso molecular:191.05 g/molMethyl 5-Hexynoate
CAS:Methyl 5-hexynoate is a synthetic product that can be synthesized from soybean lipoxygenase and hydrogenation reduction. This product has been shown to be a useful synthon for the synthesis of monoclonal antibodies with high binding affinity. The synthetic pathway, which involves cross-coupling and asymmetric synthesis, is outlined in the diagram below. The following are the steps involved in the production of methyl 5-hexynoate: 1) Addition of ethyl bromide to terminal alkynes 2) Addition of hydrochloric acid 3) Reaction with potassium tert-butoxide 4) Hydrogenation reduction 5) Cross-coupling reaction 6) Asymmetric synthesis
Fórmula:C7H10O2Pureza:Min. 95%Peso molecular:126.15 g/mol1-(3,3-Difluorocyclobutyl)ethan-1-one
CAS:Versatile small molecule scaffold
Fórmula:C6H8F2OPureza:Min. 95%Peso molecular:134.13 g/mol4-(2-Bromoethyl)morpholine hydrobromide
CAS:4-(2-Bromoethyl)morpholine hydrobromide is a solvent that is used as an agent in the production of other chemicals. It is a colorless, crystalline solid with a constant melting point of 130 to 131 degrees Celsius. 4-(2-Bromoethyl)morpholine hydrobromide is soluble in acetone, ethanol, ether, and water. This chemical has been shown to be toxic and should be handled with care.
Fórmula:C6H13Br2NOPureza:Min. 95%Peso molecular:274.98 g/molCASIN
CAS:CASIN is a lysine-derived antimicrobial agent that inhibits the growth of bacteria by binding to the peptide chains of collagen, which are found in skin and mucous membranes. CASIN has been shown to inhibit the growth of many bacterial species, including those that are resistant to other antibiotics. CASIN can be used for the treatment of infectious diseases caused by bacteria, such as bacterial vaginosis or chlamydia. CASIN has also been shown to reduce body mass index in animal models. The mechanism of action is not known but may involve interference with an enzyme that controls the biosynthesis of fatty acids. The use of CASIN in humans is limited due to its toxicity on human cells and potential safety concerns.
Fórmula:C20H22N2OPureza:Min. 95%Peso molecular:306.4 g/mol1-Hydroxycyclopentane-1-carbonitrile
CAS:1-Hydroxycyclopentane-1-carbonitrile is a monomer that is hydrolyzed to form benzoin and cyanohydrins. It can be used in the production of scifinder as a monomer or dimerizer.
Fórmula:C6H9NOPureza:Min. 95%Peso molecular:111.14 g/moltert-Butyl 6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)picolinate
CAS:Versatile small molecule scaffoldFórmula:C16H24BNO4Pureza:Min. 95%Peso molecular:305.2 g/mol2-(4-Methoxy-1H-indol-3-yl)ethan-1-amine
CAS:Produto Controlado2-(4-Methoxy-1H-indol-3-yl)ethan-1-amine is a synthetic compound that belongs to the class of organocatalysts. It is a serotonin receptor agonist, and has been shown to act as an antagonist at the 5HT2AR. This drug has been shown to have stereoselective effects in vitro, with high affinity for the S form of 5HT2AR. 2-(4-Methoxy-1H-indol-3-yl)ethan-1-amine also has some activity against dopamine receptors, but not as much as other compounds in its class. !--[if !supportLists]-->· !--[endif]-->This drug binds to speciogynine and alstovenine receptors, which are part of the opioid system.!--[if !supportLists]-->· !--[endif]-->Modelling studies suggest that 2-(4-M
Fórmula:C11H14N2OPureza:Min. 95%Cor e Forma:PowderPeso molecular:190.24 g/mol1-(4-Ethylphenyl)-2,2,2-trifluoroethan-1-ol
CAS:Versatile small molecule scaffold
Fórmula:C10H11F3OPureza:Min. 95%Peso molecular:204.19 g/mol1-Cyclobutylpiperidine-4-carboxylic acid
CAS:Versatile small molecule scaffold
Fórmula:C10H17NO2Pureza:Min. 95%Peso molecular:183.25 g/molPoly(dioxanone)
CAS:Poly(dioxanone) is a biocompatible polymer that has been shown to promote bone growth in animal models. It is a cross-linking agent and can be used as an alternative to copper chromite, which is the most common cross-linking agent used in tissue engineering. Poly(dioxanone) has been shown to promote bone growth by stimulating the production of growth factors and increasing the activity of osteoblasts, cells that produce new bone. The material also promotes matrix deposition and remodeling, leading to increased bone density.
Fórmula:(C4H6O3)nPureza:Min. 95%Cor e Forma:Powder6-Methylbenzimidazole-5-carboxylic acid
CAS:Versatile small molecule scaffold
Fórmula:C9H8N2O2Pureza:Min. 95%Peso molecular:176.17 g/molTripropylphosphine
CAS:Tripropylphosphine is a fatty acid that can be synthesized by reacting tripropyl alcohol with phosphorus trichloride. Tripropylphosphine is soluble in organic solvents, and has an optical rotation of +58°. It has been shown to have cancer-inhibiting properties, as well as the ability to inhibit tumor growth and induce apoptosis in cancer cells. This compound may also be used as a growth regulator, since it inhibits the synthesis of certain proteins and enzymes.
Fórmula:C9H21PPureza:Min. 95%Peso molecular:160.24 g/mol8-Chloro-3,7-dihydro-1H-purine-2,6-dione
CAS:8-Chloro-3,7-dihydro-1H-purine-2,6-dione is a reactive molecule that binds to the active site of bacterial cyclic nucleotide phosphodiesterases and inhibits their activity. This inhibition prevents the breakdown of cAMP and cGMP, which are important second messengers in eukaryotic cells. 8-Chloro-3,7-dihydro-1H-purine-2,6-dione is also a potent inhibitor of protein synthesis and has been used in research studies on wheat leaves.
Fórmula:C5H3N4O2ClPureza:Min. 95%Cor e Forma:PowderPeso molecular:186.56 g/molRef: 3D-FC09024
Produto descontinuadoH-Ala-Ala-Pro-OH trifluoroacetate
CAS:Please enquire for more information about H-Ala-Ala-Pro-OH trifluoroacetate including the price, delivery time and more detailed product information at the technical inquiry form on this page
Fórmula:C11H19N3O4•C2HF3O2Pureza:Min. 95%Peso molecular:371.31 g/molRef: 3D-FA183453
Produto descontinuado4,5-Dihydroxy-2,3-Pentanedione
CAS:4,5-Dihydroxy-2,3-pentanedione is a carbonyl compound that is the product of the oxidation of ascorbic acid. It is used in wastewater treatment and has antimicrobial properties against infectious diseases. This compound has been shown to inhibit protein synthesis by binding to the ribosome and preventing the formation of peptide bonds between amino acids. 4,5-Dihydroxy-2,3-pentanedione has also been shown to bind to plasma proteins, which may be due to its acyl chain structure. 4,5-Dihydroxy-2,3-pentanedione can be synthesized in a catalytic mechanism that involves dehydroascorbic acid and molecular oxygen.
Fórmula:C5H8O4Pureza:Min. 95%Cor e Forma:PowderPeso molecular:132.11 g/molRef: 3D-FD180770
Produto descontinuado5-Chloro-3-methylpyridazine hydrochloride
CAS:Versatile small molecule scaffoldFórmula:C5H6Cl2N2Pureza:Min. 95%Peso molecular:165 g/mol1-(3-Amino-1H-pyrazol-1-yl)-2-methylpropan-2-ol
CAS:Versatile small molecule scaffold
Fórmula:C7H13N3OPureza:Min. 95%Peso molecular:155.2 g/mol(R)-tert-Butyl 1-(3-aminopyridin-2-yl)pyrrolidin-3-ylcarbamate
CAS:Versatile small molecule scaffoldFórmula:C14H22N4O2Pureza:Min. 95%Peso molecular:278.35 g/molRef: 3D-IZB85984
Produto descontinuadoFmoc-2,6-dichloro-L-phenylalanine
CAS:Please enquire for more information about Fmoc-2,6-dichloro-L-phenylalanine including the price, delivery time and more detailed product information at the technical inquiry form on this page
Fórmula:C24H19Cl2NO4Pureza:Min. 95%Peso molecular:456.32 g/mol2-[(tert-Butoxy)carbonyl]-2-azabicyclo[3.1.0]hexane-5-carboxylic acid
CAS:Versatile small molecule scaffold
Fórmula:C11H17NO4Pureza:Min. 95%Peso molecular:227.26 g/mol1-(Pyrimidin-5-yl)propan-1-one
CAS:Versatile small molecule scaffold
Fórmula:C7H8N2OPureza:Min. 95%Peso molecular:136.15 g/molChloromethyl cyclohexyl ether
CAS:Chloromethyl cyclohexyl ether is a light-sensitive cross-linking agent that can be activated by light. It has two functional groups, a hydroxyl group and a chlorine atom. The skeleton of chloromethyl cyclohexyl ether is composed of an alicyclic hydrocarbon with six carbons and the molecule contains two divalent hydrocarbons, one of which is a trifluoromethyl group. Chloromethyl cyclohexyl ether has been used as a solid catalyst in the synthesis of amides and is also used in hyperproliferative diseases such as cancer.
Fórmula:C7H13ClOPureza:Min. 95%Peso molecular:148.63 g/mol5-Methyl-1-(piperidin-4-yl)-1H-pyrazole-4-carboxylic acid dihydrochloride
CAS:Versatile small molecule scaffoldFórmula:C10H17Cl2N3O2Pureza:Min. 95%Peso molecular:282.16 g/mol4-(Benzyloxy)thiophenol
CAS:Versatile small molecule scaffold
Fórmula:C13H12OSPureza:Min. 95%Peso molecular:216.3 g/mol±,±,±²,±²-Tetramethyl-1,3-benzenedipropionic acid
CAS:Versatile small molecule scaffold
Fórmula:C16H22O4Pureza:Min. 95%Peso molecular:278.34 g/molN-(2-Methyl-6-benzoxazolyl)-2-propenamide
CAS:Please enquire for more information about N-(2-Methyl-6-benzoxazolyl)-2-propenamide including the price, delivery time and more detailed product information at the technical inquiry form on this page
Fórmula:C11H10N2O2Pureza:Min. 95%Peso molecular:202.21 g/molRef: 3D-FM184094
Produto descontinuadoMethyl 4-chloro-5-hydroxy-3-pyridinecarboxylate
CAS:Versatile small molecule scaffold
Fórmula:C7H6ClNO3Pureza:Min. 95%Peso molecular:187.58 g/molPiperyline
CAS:Piperyline is an alkanoic acid that has shown to be effective against skin cancer. It also has antimicrobial properties, which may be due to its ability to bind metal ions and form polymeric compounds. Piperyline inhibits microbial growth by inhibiting the synthesis of proteins and nucleic acids. The antimicrobial activity is related to its cationic polymerization with hydroxyl groups, which forms a structure that can inhibit microbial enzymes and disrupt microbial cell membranes. This compound also interacts with the skin's natural lipids, making it difficult for microorganisms to attach and grow on the skin. Piperyline is synthesized in organic chemistry laboratories as an amide precursor of other pharmaceuticals such as penicillin.
Fórmula:C16H17NO3Pureza:Min. 95%Peso molecular:271.31 g/molMacaridine
CAS:Please enquire for more information about Macaridine including the price, delivery time and more detailed product information at the technical inquiry form on this page
Fórmula:C13H13NO2Pureza:Min. 95%Peso molecular:215.25 g/molRef: 3D-FM183770
Produto descontinuado2,5-Dimethoxytetrahydrofuran
CAS:2,5-Dimethoxytetrahydrofuran is an organic compound that can be synthesized from 2,5-dimethoxybenzaldehyde and tetrahydrofuran. The asymmetric synthesis of this compound was first reported in 1968. The nmr spectrum of 2,5-dimethoxytetrahydrofuran shows two signals at δ 5.89 and δ 7.03 ppm. This compound is soluble in water and organic solvents such as dichloromethane, benzene, toluene, chloroform, and methanol. 2,5-Dimethoxytetrahydrofuran has been shown to have pain-relieving effects using the formalin test in mice and rats. It also has antineoplastic properties when used with other quinoline derivatives.br>br> 2,5-Dimethoxytetrahydrofuran is a white solid
Fórmula:C6H12O3Pureza:Min. 95%Cor e Forma:PowderPeso molecular:132.16 g/molRef: 3D-FD00819
Produto descontinuadoNor reticuline
CAS:Norreticuline is a virus-induced gene that is primarily found in the opium poppy, Papaver somniferum. Norreticuline has been shown to be biosynthesized from reticuline by a series of enzymatic reactions. It is also involved in the metabolic pathway of papaverine, which is an alkaloid that has been used as a vasodilator and anti-hypertensive drug. The optimum pH for norreticuline production is between 6 and 7. Norreticuline has demonstrated anticancer activity against various tumor cells, such as breast cancer cells and colon cancer cells. Norreticuline may also have antiviral properties due to its ability to inhibit viral DNA replication and synthesis of viral proteins.
Fórmula:C18H21NO4Pureza:Min. 95%Peso molecular:315.36 g/mol4-Bromothiophene-2-acetic acid
CAS:Versatile small molecule scaffold
Fórmula:C6H5BrO2SPureza:Min. 95%Peso molecular:221.07 g/mol
