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Pfitzinger Reaction
The Pfitzinger reaction (also known as the Pfitzinger-Borsche reaction) is the chemical reaction of isatin with base and a carbonyl compound to yield substituted quinoline-4-carboxylic acids. Several reviews have been published. Reaction mechanism The reaction of isatin with a base such as potassium hydroxide hydrolyses the amide bond to give the keto-acid 2. This intermediate can be isolated, but is typically not. A ketone (or aldehyde) will react with the aniline to give the imine (3) and the enamine (4). The enamine will cyclize and dehydrate to give the desired quinoline (5). Variations Halberkann variant Reaction of ''N''-acyl isatins with base gives 2- hydroxy-quinoline-4-carboxylic acids. See also *Camps quinoline synthesis *Friedländer synthesis *Niementowski quinazoline synthesis *Talnetant, Cinchocaine Cinchocaine (INN/ BAN) or dibucaine (USAN) is an amide local anesthetic. Among the most potent and toxic of the long-acting local anesthetics, current use of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilhelm Pfitzinger , the Dutch national anthem
{{Disambiguation ...
Wilhelm may refer to: People and fictional characters * William Charles John Pitcher, costume designer known professionally as "Wilhelm" * Wilhelm (name), a list of people and fictional characters with the given name or surname Other uses * Mount Wilhelm, the highest mountain in Papua New Guinea * Wilhelm Archipelago, Antarctica * Wilhelm (crater), a lunar crater See also * Wilhelm scream, a stock sound effect * SS ''Kaiser Wilhelm II'', or USS ''Agamemnon'', a German steam ship * Wilhelmus "Wilhelmus van Nassouwe", usually known just as "Wilhelmus" ( nl, Het Wilhelmus, italic=no; ; English translation: "The William"), is the national anthem of both the Netherlands and the Kingdom of the Netherlands. It dates back to at least 1572 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imine
In organic chemistry, an imine ( or ) is a functional group or organic compound containing a carbon–nitrogen double bond (). The nitrogen atom can be attached to a hydrogen or an organic group (R). The carbon atom has two additional single bonds. Imines are common in synthetic and naturally occurring compounds and they participate in many reactions. Structure For ketimines and aldimines, respectively, the five core atoms (C2C=NX and C(H)C=NX, X = H or C) are coplanar. Planarity results from the sp2-hybridization of the mutually double-bonded carbon and the nitrogen atoms. The C=N distance is 1.29-1.31 Å for nonconjugated imines and 1.35 Å for conjugated imines. By contrast, C-N distances in amines and nitriles are 1.47 and 1.16 Å, respectively. Rotation about the C=N bond is slow. Using NMR spectroscopy, both E- and Z-isomers of aldimines have been detected. Owing to steric effects, the E isomer is favored. Nomenclature and classification The term "imine" was coine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinoline Forming Reactions
Quinoline is a heterocyclic aromatic organic compound with the chemical formula C9H7N. It is a colorless hygroscopic liquid with a strong odor. Aged samples, especially if exposed to light, become yellow and later brown. Quinoline is only slightly soluble in cold water but dissolves readily in hot water and most organic solvents. Quinoline itself has few applications, but many of its derivative (chemistry), derivatives are useful in diverse applications. A prominent example is quinine, an alkaloid found in plants. Over 200 biologically active quinoline and quinazoline alkaloids are identified. 4-Hydroxy-2-alkylquinolines (HAQs) are involved in antibiotic resistance. Occurrence and isolation Quinoline was first extracted from coal tar in 1834 by German chemist Friedlieb Ferdinand Runge; he called quinoline ''leukol'' ("white oil" in Greek). Coal tar remains the principal source of commercial quinoline. In 1842, French chemist Charles Frédéric Gerhardt, Charles Gerhardt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensation Reactions
In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a dehydration synthesis. However other molecules can also be lost, such as ammonia, ethanol, acetic acid and hydrogen sulfide. The addition of the two molecules typically proceeds in a step-wise fashion to the addition product, usually in equilibrium, and with loss of a water molecule (hence the name condensation). The reaction may otherwise involve the functional groups of the molecule, and is a versatile class of reactions that can occur in acidic or basic conditions or in the presence of a catalyst. This class of reactions is a vital part of life as it is essential to the formation of peptide bonds between amino acids and to the biosynthesis of fatty acids. Many variations of condensation reactions exist. Common examples include the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinchocaine
Cinchocaine (INN/ BAN) or dibucaine (USAN) is an amide local anesthetic. Among the most potent and toxic of the long-acting local anesthetics, current use of cinchocaine is generally restricted to spinal and topical anesthesia. It is sold under the brand names Cincain, Nupercainal, Nupercaine and Sovcaine. Medical use Cinchocaine is the active ingredient in some topical hemorrhoid creams such as Proctosedyl. It is also a component of the veterinary drug Somulose, used for euthanasia of horses and cattle. Physical properties Cinchocaine is relatively insoluble in alkaline aqueous solutions. See also * Dibucaine number Dibucaine, also known as cinchocaine, is an amino amide local anesthetic. When administered to humans intravenously, it is capable of inhibiting the plasma cholinesterase (butyrylcholinesterase) enzyme. The dibucaine number is used to differentiate ... References Further reading * * * * Local anesthetics Quinolines Phenol ethers Carboxamides Diethyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Talnetant
Talnetant (SB-223,412) is a neurokinin 3 receptor antagonist developed by GlaxoSmithKline, which is being researched for several functions (primarily treatment of irritable bowel syndrome, despite a 2007 study finding no statistically significant improvement in rectal hypersensitivity over placebo). Its use as a potential antipsychotic drug for the treatment of schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withdra ... has also been discontinued. See also * Tachykinin receptor 3 § Agonists References Antipsychotics NK3 receptor antagonists Quinolinols Carboxamides {{pharma-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niementowski Quinazoline Synthesis
The Niementowski quinazoline synthesis is the chemical reaction of anthranilic acids with amides to form 4-oxo-3,4-dihydroquinazolines (3''H''-quinazolin-4-ones). Uses Research has demonstrated that the Niementowski quinazoline synthesis could be employed for the creation of potential EGFR-inhibiting molecules. Hensbergen ''et al''. have shown a synthetic route to a new class of privileged tri- and tetra-cyclic quinazolines containing a medium-sized ring. A nucleophilic aromatic substitution is combined with the Niementowski reaction and a BOP-mediated ring closure to afford several analogues. References # # # # {{cite journal, last1 = Hensbergen, first1 = Albertus Wijnand, last2 = Mills, first2 = Vanessa R., last3 = Collins, first3 = Ian, last4 = Jones, first4 = Alan M., year = 2015, title = An expedient synthesis of oxazepino and oxazocino quinazolines, journal = Tetrahedron Lett. ''Tetrahedron Letters'' is a weekly international journal for rapid publication of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedländer Synthesis
The Friedländer synthesis is a chemical reaction of 2-aminobenzaldehydes with ketones to form quinoline derivatives. It is named after German chemist Paul Friedländer (1857–1923). This reaction has been catalyzed by trifluoroacetic acid, toluenesulfonic acid, iodine, and Lewis acids. Several reviews have been published. Mechanism Two viable reaction mechanisms exist for this reaction. In the first mechanism 2-amino substituted carbonyl compound 1 and carbonyl compound 2 react in a rate-limiting step to aldol adduct 3. This intermediate loses water in an elimination reaction to unsaturated carbonyl compound 4 and then loses water again in imine formation to quinoline 7. In the second mechanism the first step is Schiff base formation to 5 followed by Aldol reaction to 6 and elimination to 7. : The Pfitzinger reaction and the Niementowski quinoline synthesis are variations of the Friedländer reaction. See also * Doebner-Miller reaction *Povarov reaction *Skraup reaction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camps Quinoline Synthesis
The Camps quinoline synthesis (also known as the Camps cyclization) is a chemical reaction whereby an o-acylaminoacetophenone is transformed into two different hydroxyquinolines (products A and B) using hydroxide ion. The relative proportions of the hydroxyquinolines (A and B) produced are dependent upon the reaction conditions and structure of the starting material. Although the reaction product is commonly depicted as a quinoline (the enol form), it is believed that the keto form predominates in both the solid state and in solution, making the compound a quinolone. An example of the Camps reaction is given below:''Sequential Cu-Catalyzed Amidation-Base-Mediated Camps Cyclization: A Two-Step Synthesis of 2-Aryl-4-quinolones from o-Halophenones'' Jones, C. P.; Anderson, K. W.; Buchwald, S. L. J. Org. Chem.; (Article); 2007; 72(21); 7968-7973. The amides of 1,3-enaminoketones react to form pyridinones-2 under similar conditions. Camps Reaction and Related Cyclizations. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxyl
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy groups. Both the negatively charged anion , called hydroxide, and the neutral radical , known as the hydroxyl radical, consist of an unbonded hydroxy group. According to IUPAC definitions, the term ''hydroxyl'' refers to the hydroxyl radical () only, while the functional group is called a ''hydroxy group''. Properties Water, alcohols, carboxylic acids, and many other hydroxy-containing compounds can be readily deprotonated due to a large difference between the electronegativity of oxygen (3.5) and that of hydrogen (2.1). Hydroxy-containing compounds engage in intermolecular hydrogen bonding increasing the electrostatic attraction between molecules and thus to higher boiling and melting points than found for compounds that lack this f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acyl
In chemistry, an acyl group is a moiety derived by the removal of one or more hydroxyl groups from an oxoacid, including inorganic acids. It contains a double-bonded oxygen atom and an alkyl group (). In organic chemistry, the acyl group (IUPAC name: alkanoyl) is usually derived from a carboxylic acid, in which case it has the formula , where R represents an alkyl group that is linked to the carbon atom of the group by a single bond. Although the term is almost always applied to organic compounds, acyl groups can in principle be derived from other types of acids such as sulfonic acids and phosphonic acids. In the most common arrangement, acyl groups are attached to a larger molecular fragment, in which case the carbon and oxygen atoms are linked by a double bond. Compounds Well-known acyl compounds are the acyl chlorides, such as acetyl chloride (CH3COCl) and benzoyl chloride (C6H5COCl). These compounds, which are treated as sources of acylium cations, are good reagents for attac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
