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Oxatomide Synthesis
Oxatomide, sold under the brand name Tinset among others, is a first-generation antihistamine of the diphenylmethylpiperazine family which is marketed in Europe, Japan, and a number of other countries. It was discovered at Janssen Pharmaceutica in 1975. Oxatomide lacks any anticholinergic effects. In addition to its H1 receptor antagonism, it also possesses antiserotonergic activity similarly to hydroxyzine. It was patented in 1976 and came into medical use in 1981. Chemistry Synthesis Reaction of 2-Benzimidazolinone with isopropenyl acetate leads to the singly protected imidazolone derivative (2). Alkylation of this with 3-chloro-1-bromopropane affords the functionalized derivative (3). Alkylation of the monobenzhydryl derivative of piperazine (4) with 3 gives oxatomide (5), after hydrolytic removal of the protecting group A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oral Administration
Oral administration is a route of administration where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for medication to be taken orally. Many medications are taken orally because they are intended to have a systemic effect, reaching different parts of the body via the bloodstream, for example. Oral administration can be easier and less painful than other routes, such as injection. However, the onset of action is relatively low, and the effectiveness is reduced if it is not absorbed properly in the digestive system, or if it is broken down by digestive enzymes before it can reach the bloodstream. Some medications may cause gastrointestinal side effects, such as nausea or vomiting, when taken orally. Oral administration can also only be applied to conscious patients, and patients willing and able to swallow. Terminology ''Per os'' (; ''P.O.'') is an adverbial phrase meaning literally from Latin "through the mouth" or "by mouth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isopropenyl Acetate
Isopropenyl acetate is an organic compound, which is the acetate ester of the enol tautomer of acetone. This colorless liquid is significant commercially as the principal precursor to acetylacetone. In organic synthesis, it is used to prepare enol acetates of ketones and acetonides from diols. Preparation and reactions Isopropenyl acetate is prepared by treating acetone with ketene In organic chemistry, a ketene is an organic compound of the form , where R and R' are two arbitrary monovalent chemical groups (or two separate substitution sites in the same molecule). The name may also refer to the specific compound eth .... Upon heating over a metal surface, isopropenyl acetate rearranges to acetylacetone. Isopropenyl acetate is used to prepare other isopropenyl esters by transesterification.{{cite journal, journal=Org. Synth., year=2012, volume=89, pages=307–310, doi=10.15227/orgsyn.089.0307, title=Discussion Addendum for: Iridium-catalyzed Synthesis of Vinyl Ethers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
H1 Receptor Antagonists
H1 antagonists, also called H1 blockers, are a class of medications that block the action of histamine at the H1 receptor, helping to relieve allergic reactions. Agents where the main therapeutic effect is mediated by negative modulation of histamine receptors are termed antihistamines; other agents may have antihistaminergic action but are not true antihistamines. In common use, the term "antihistamine" refers only to H1-antihistamines. Virtually all H1-antihistamines function as inverse agonists at the histamine H1-receptor, as opposed to neutral antagonists, as was previously believed. Medical uses H1-antihistamines are clinically used in the treatment of histamine-mediated allergic conditions. These indications may include:Rossi S (Ed.) (2004). ''Australian Medicines Handbook 2004''. Adelaide: Australian Medicines Handbook. * Allergic rhinitis * Allergic conjunctivitis * Allergic dermatological conditions ( contact dermatitis) * Rhinorrhea (runny nose) * Urticari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belgian Inventions
Belgian may refer to: * Something of, or related to, Belgium * Belgians, people from Belgium or of Belgian descent * Languages of Belgium, languages spoken in Belgium, such as Dutch, French, and German *Ancient Belgian language, an extinct language formerly spoken in Gallia Belgica *Belgian Dutch or Flemish, a variant of Dutch *Belgian French, a variant of French *Belgian horse (other), various breeds of horse *Belgian waffle, in culinary contexts * SS ''Belgian'', a cargo ship in service with F Leyland & Co Ltd from 1919 to 1934 *''The Belgian'', a 1917 American silent film See also * *Belgica (other) Gallia Belgica was a province of the Roman Empire in present-day Belgium, Luxembourg, and the Netherlands. Belgica may also refer to: Places * Belgica Glacier, Antarctica * Belgica Guyot, an undersea tablemount off Antarctica * Belgica Mountai ... * Belgic (other) {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzimidazoles
Benzimidazole is a heterocyclic aromatic organic compound. This bicyclic compound may be viewed as fused rings of the aromatic compounds benzene and imidazole. It is a colorless solid. Preparation Benzimidazole is produced by condensation of o-phenylenediamine with formic acid,. or the equivalent trimethyl orthoformate: :C6H4(NH2)2 + HC(OCH3)3 → C6H4N(NH)CH + 3 CH3OH 2-substituted derivatives are obtained when the condensation is conducted with aldehydes in place of formic acid, followed by oxidation.Robert A. Smiley "Phenylene- and Toluenediamines" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. Reactions Benzimidazole is a base: :C6H4N(NH)CH + H+ → 6H4(NH)2CHsup>+ It can also be deprotonated with stronger bases: :C6H4N(NH)CH + LiH → Li 6H4N2CH + H2 The imine can be alkylated and also serves as a ligand in coordination chemistry. The most prominent benzimidazole complex features ''N''-ribosyl-dimethylbenzimidazole as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharmacodynamics
Pharmacodynamics (PD) is the study of the biochemical and physiologic effects of drugs (especially pharmaceutical drugs). The effects can include those manifested within animals (including humans), microorganisms, or combinations of organisms (for example, infection). Pharmacodynamics and pharmacokinetics are the main branches of pharmacology, being itself a topic of biology interested in the study of the interactions between both endogenous and exogenous chemical substances with living organisms. In particular, pharmacodynamics is the study of how a drug affects an organism, whereas pharmacokinetics is the study of how the organism affects the drug. Both together influence dosing, benefit, and adverse effects. Pharmacodynamics is sometimes abbreviated as PD and pharmacokinetics as PK, especially in combined reference (for example, when speaking of PK/PD models). Pharmacodynamics places particular emphasis on dose–response relationships, that is, the relationships betwee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protecting Group
A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectivity in a subsequent chemical reaction. It plays an important role in multistep organic synthesis. In many preparations of delicate organic compounds, some specific parts of their molecules cannot survive the required reagents or chemical environments. Then, these parts, or groups, must be protected. For example, lithium aluminium hydride is a highly reactive but useful reagent capable of reducing esters to alcohols. It will always react with carbonyl groups, and this cannot be discouraged by any means. When a reduction of an ester is required in the presence of a carbonyl, the attack of the hydride on the carbonyl has to be prevented. For example, the carbonyl is converted into an acetal, which does not react with hydrides. The acetal is then called a protecting group for the carbonyl. After the step involving the hydride is complete, the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piperazine
Piperazine () is an organic compound that consists of a six-membered ring containing two nitrogen atoms at opposite positions in the ring. Piperazine exists as small alkaline deliquescent crystals with a saline taste. The piperazines are a broad class of chemical compounds, many with important pharmacological properties, which contain a core piperazine functional group. Origin and naming Piperazines were originally named because of their chemical similarity with piperidine, part of the structure of piperine in the black pepper plant (''Piper nigrum''). The -az- infix added to "piperazine" refers to the extra nitrogen atom, compared to piperidine. It is important to note, however, that piperazines are ''not'' derived from plants in the '' Piper'' genus. Chemistry Piperazine is freely soluble in water and ethylene glycol, but insoluble in diethyl ether. It is a weak base with two pKb of 5.35 and 9.73 at 25 °C.; the pH of a 10% aqueous solution of piperazine is 10.8–11.8. Pipe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzhydryl Compounds
The benzhydryl compounds are a group of organic compounds whose parent structures include diphenylmethane (which is two benzene rings connected by a single methane), with any number of attached substituents, including bridges. This group typically excludes compounds in which either benzene is fused to another ring (bicyclic, tricyclic, polycyclic) or includes a heteroatom, or where the methane connects to three or four benzenes. The benzhydryl ''radical'' can be abbreviated or Bzh. Carboaromatic Alcohols *''Acyclic:'' pridinol *''Pyrolidino:'' diphenylprolinol *''2-Piperidine:'' pipradrol *''4-Piperidine:'' terfenadine, fexofenadine *''Benzilic ester:'' QNB, JB-336, JB-318, benactyzine Alkenes *''Tricycle:'' amitriptyline, melitracen, cyclobenzaprine, tianeptine, amineptine, clopenthixol, chlorprothixene, flupentixol, thiothixene, zuclopenthixol *''Tricyclic and piperidine:'' pimethixene, cyproheptadine *''Acyclic:'' gilutensin Alkyl(amine)s *''Acyclic:'' (3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkylation
Alkylation is the transfer of an alkyl group from one molecule to another. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting alkylation. Alkyl groups can also be removed in a process known as dealkylation. Alkylating agents are often classified according to their nucleophilic or electrophilic character. In oil refining contexts, alkylation refers to a particular alkylation of isobutane with olefins. For upgrading of petroleum, alkylation produces a premium blending stock for gasoline. In medicine, alkylation of DNA is used in chemotherapy to damage the DNA of cancer cells. Alkylation is accomplished with the class of drugs called alkylating antineoplastic agents. Nucleophilic alkylating agents Nucleophilic alkylating agents deliver the equivalent of an alkyl anion ( carbanion). The formal "alkyl anion" attacks an electrophile, forming a new cova ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
