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Topic: Acyl group

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  Acyl halide - Wikipedia, the free encyclopedia
In chemistry, the term acyl halide (also known as acid halide) refers to a compound derived from an acid by replacing a hydroxyl group with a halide group.
A common method for the synthesis of acyl halides in the laboratory is by reaction of carboxylic acids with reagents such as thionyl chloride and phosphorus pentachloride for acyl halides, phosphorus tribromide for acyl bromides and cyanuric fluoride for acyl fluorides
Acyl halides are artificial (meaning not found in nature), rather reactive compounds often synthesized to be used as intermediates in the synthesis of other organic compounds.
en.wikipedia.org /wiki/Acyl_halide   (510 words)

 Acyl - Wikipedia, the free encyclopedia
In chemistry, the term acyl or acyl group refers to a functional group obtained from an acid by removal of a hydroxyl group.
It therefore has the formula RC(=O)-, with a double bond between the carbon and oxygen atoms (thus forming a carbonyl group), and a single bond between R and the carbon; R denotes the group that occurs in the original carboxylic acid RCOOH.
Acyl groups can also be derived from other types of acids such as sulfonic acids, phosphonic acids, and some others.
en.wikipedia.org /wiki/Acyl   (243 words)

 Pharmaceutical preparations containing (+)-cyanidan-3-ol derivatives, the use thereof, novel substituted ...
Lower alkyl groups are for example: methyl as well as ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, isohexyl or n-heptyl groups; lower alkenyl groups are for example: vinyl, allyl, 1-propenyl, isopropenyl, 1- or 2-methylallyl or 2- or 3-butenyl groups, and lower alkynyl groups are for example: propargyl or 2-butynyl groups.
The acyl radicals of an aliphatic carboxylic acid are in particular acyl radicals of alkanecarboxylic acids, especially lower-alkanecarboxylic acids of lower-alkanedicarboxylic-acids, but also of alkenecarboxylic acids, particularly of lower-alkenecarboxylic acids or lower-alkenedicarboxylic acids, and also of substituted lower-alkanecarboxylic acids, such as trifluoroacetic acid.
A reactive esterified hydroxyl group X is preferably a hydroxyl group esterified by a strong mineral or sulfonic acid, such as a hydrohalic acid, sulfuric acid, lower-alkanesulfonic acid or benzene-sulfonic acid, for example hydrochloric, hydrobromic, methanesulfonic, trifluoromethanesulfonic, benzenesulfonic or p-toluenesulfonic acid.
xrint.com /patents/us/4644011   (9471 words)

 O=CHem Nucleophilic Acyl Substitution
The same alternatives outlined in Figure 1 for the carbonyl group are possible for the acyl group.
It is the principal reaction pathway of the acyl group.
In other words, nucleophilic addition of hydroxide ion to the carbon atom of an acyl group is about as likely as nucleophilic addition to the carbon atom of a carbonyl group.
www.usm.maine.edu /~newton/Chy251_253/Lectures/AcylSubstitution/AcylSubstitution.html   (696 words)

 an introduction to acyl chlorides (acid chlorides)
The strong smell of ethanoyl chloride is a mixture of the smell of vinegar (ethanoic acid) and the acrid smell of hydrogen chloride gas.
Acyl chlorides can't be said to dissolve in water because they react (often violently) with it.
Acyl chlorides are extremely reactive, and in their reactions the chlorine atom is replaced by other things.
www.chemguide.co.uk /organicprops/acylchlorides/background.html   (618 words)

 Carboxylic Acids   (Site not responding. Last check: 2007-09-30)
The Acyl Halide Family is a family of organic compounds with the functional group being the -COX.
This group is attached to one of the carbons in the rest of the molecule.
Acyl Halides cannot be prepared from one of the members of the other acyl families because they represent the most reactive of the families.
members.aol.com /profchm/acylhal.html   (1220 words)

 Title of Invention: Fatty acyl reductase
Fatty acyl groups are major components of many lipids, and their long, non-polar hydrocarbon chain is responsible for the water-insoluble nature of these lipid molecules.
A fatty acyl reductase of this invention includes any sequence of amino acids, such as protein, polypeptide or peptide fragment, which is active in catalyzing the reduction of a fatty acyl group to the corresponding alcohol.
In embodiments wherein the expression of the acyl reductase protein is desired in a plant host, the use of all or part of the complete plant acyl reductase gene may be desired, namely the 5' upstream non-coding regions (promoter) together with the structural gene sequence and 3' downstream non-coding regions may be employed.
www.nal.usda.gov /bic/Biotech_Patents/1995patents/05403918.html   (13277 words)

 [No title]   (Site not responding. Last check: 2007-09-30)
In the first example, the parent chain is a pentane and the acyl group is assigned as carbon #1.
Select the longest continuous carbon chain containing the acyl group, and derive the parent name by replacing the -e ending with -oate, then append the the alcohol to the front of the name.
In the first example, the alcohol is methanol the parent chain is a pentane and the acyl group is assigned as carbon #1.
www.chem.uic.edu /web1/OCOL3/CH21/NOMEN.HTM   (1432 words)

 Substituted guanidine derivatives (US5814654)
is a hydrogen atom, an unsubstituted alkyl group, a substituted alkyl group, a cycloalkyl group, a cycloalkenyl group, a saturated heterocyclic group, an aromatic group, --OR, an acyl aromatic group, --Q--R
is a hydrogen atom, an unsubstituted alkyl group, a substituted alkyl group, a cycloalkyl group, a cycloalkenyl group, a saturated heterocyclic group or an aromatic group;
is a hydrogen atom, an unsubstituted alkyl group, a substituted alkyl group, a cycloalkyl group, a saturated heterocyclic group, an aromatic group, an acyl group or --Q--R
www.delphion.com /details?pn=US05814654__&language=en   (880 words)

 17-methylene- and 17-ethylidene-estratrienes - United States Patent 4,977,147
A pharmaceutical preparation for treating menopausal symptoms, estrogen deficiency and hormone-dependent tumors, and for use as a contraceptive, comprises a compound of formula I ##STR1## wherein R.sub.1 is hydrogen, methyl, a tetrahydropyranyl group or an acyl group and R.sub.2 is hydrogen or methyl.
Suitable acyl groups are physiologically compatible groups derived from acids customarily used for the esterification of hydroxy steroids.
Suitable acyl groups include organic carboxylic acids of 1-12 carbon atoms, e.g., hydrocarbon acids, pertaining to the aliphatic, cycloaliphatic, aromatic or aromatic-aliphatic series which can be saturated or unsaturated, mono- or poly-basic and/or substituted.
xrint.com /patents/us/4977147   (2456 words)

 Catabolism of Fatty Acids
Nucleophilic attack of the sulfur group of CoA on the carbonyl carbon of the fatty acyl-AMP intermediate.
The acyl group is moved from carnitine to CoA in the matrix space.
Acyl chains of fatty acids are hydrocarbon whereas carbohydrates are partially oxidized.
www.nitorig.net /lec34.html   (439 words)

 acyl - Definition, Synonyms, and Reference from OnPedia.com
acyl - any group or radical of the form RCO- where R is an organic group; "an example of the acyl group is the acetyl group"
acetyl, acetyl group, acetyl radical, ethanoyl group, ethanoyl radical - the organic group of acetic acid (CH3CO-)
chemical group, radical, group - (chemistry) two or more atoms bound together as a single unit and forming part of a molecule
www.onpedia.com /dictionary/acyl   (73 words)

 Acylation - Biocrawler   (Site not responding. Last check: 2007-09-30)
In chemistry, acylation is the process of adding an acyl group to a compound.
Because they form a strong electrophile when treated with some metal catalysts, acyl halides are commonly used as acylating agents.
Anhydrides of carboxylic acids are also commonly used acylating agents to acylate amines to form amides or acylate alcohols to form esters.
www.biocrawler.com /encyclopedia/Acylation   (218 words)

 Acyl Families and Nucleophilic Reactions   (Site not responding. Last check: 2007-09-30)
Acyl Families are families that have the acyl group as a part of their structure.
In a nucleophilic reaction that group is the potential leaving group that would be displaced during a nucleophilic substitution.
The factor that decides whether the acyl compound will undergo addition or substitution largely depends upon the ability for the "Y" group attached to the acyl carbon to be displaced by the incoming nucleophile.
members.aol.com /logan20/nucleo.html   (789 words)

 [No title]   (Site not responding. Last check: 2007-09-30)
Acetyl group is transferred to the Cys residue and malonyl group to the phosphopantetheine group from their CoA esters by specific transferases.
The keto group undergoes reduction to hydroxy and then a molecule of water is removed to yield an unsaturated acyl group.
Glycerol phosphate (from carbohydrate metabolism) is acylated by transferring saturated fatty acyl group to the hydroxyl at C-1 and unsaturated fatty acyl group to C-2 from the respective CoA esters to generate phosphatydic acid.
www.neurobiotech.ohio-state.edu /Handout.doc   (2186 words)

 Carboxyl Derivative Reactivity
Carboxylic acids have a hydroxyl group bonded to an acyl group, and their functional derivatives are prepared by replacement of the hydroxyl group with substituents, such as halo, alkoxyl, amino and acyloxy.
The exceptional reactivity of acyl halides, on the other hand, facilitates their reduction under mild conditions, by using a poisoned palladium catalyst similar to that used for the partial reduction of alkynes to alkenes.
The organometallic reagent is a source of a nucleophilic alkyl or aryl group (colored purple), which bonds to the electrophilic carbon of the carbonyl group (colored orange).
www.cem.msu.edu /~reusch/VirtualText/crbacid2.htm   (3950 words)

 Pesticidal use of N-chlorocrotyl acyl compositions - Patent 4177289
The method of claim 3 wherein the inert diluent is selected from the group consisting of finely divided inert solids, granular solids, surface active dispersing agents, beeswax, paraffin waxes, water, organic solvents, nitrogen fertilizer and potassium fertilizer.
The method of claim 1 wherein R.sub.2 to R.sub.7 are selected from the group consisting of hydrogen, chlorine and alkyl groups having from 1 to 5 carbon atoms.
The pesticidal composition of claim 8 wherein R.sub.2 to R.sub.7 are selected from the group consisting of hydrogen, chlorine and alkyl groups having from 1 to 5 carbon atoms.
www.freepatentsonline.com /4177289.html   (4409 words)

 Fatty Acids -- Enzymes and Isolated Reactions: Activities of FA Synthase   (Site not responding. Last check: 2007-09-30)
Mechanistically this is a two step process, in which the group is first transferred to the ACP (acyl carrier peptide), and then to the cysteine -SH group of the condensing enzyme domain.
In the third reaction the acetyl group is transferred to the malonyl group with the release of carbon dioxide:
In the fifth reaction the beta-hydroxybutyryl-ACP is dehydrated to form a trans- monounsaturated fatty acyl group by the beta-hydroxyacyl dehydratase activity:
www-medlib.med.utah.edu /NetBiochem/FattyAcids/5_2b.html   (333 words)

 [No title]
—CO—A—Hal group, wherein A is an alkylene or alkylidene group, X is hydrogen or an acyl radical of an organic or inorganic acid, Hal is a halogen atom, and n is 0 or 1 [3]
 the reactive group being an esterified or non-esterified hydroxyalkyl sulfonyl or mercaptoalkyl sulfonyl group, a quaternised or non-quaternised aminoalkyl sulfonyl group, a heterylmercapto alkyl sulfonyl group, a vinyl sulfonyl or a substituted vinyl sulfonyl group, or a thiophene-dioxide group [3]
 the reactive group being an esterified or non-esterified hydroxyalkyl sulfonyl amido or hydroxyalkyl amino sulfonyl group, a quaternised or non-quaternised amino alkyl sulfonyl amido group, or a substituted alkyl amino sulfonyl group, or a halogen alkyl sulfonyl amido or halogen alkyl amino sulfonyl group or a vinyl sulfonylamido or a substituted vinyl sulfonamido group [3]
www.wipo.int /ibis/ipc7beta6/pview.php?entry=C09B06244   (282 words)

 Process for preparing 1.alpha.-hydroxylated compounds - Patent 4260549
It is evident that Paaren et al protected the 1.alpha.-hydroxy function group by conversion to a 1.alpha.-O-acyl group, because of the reasonable expectation that the sensitive allylic 1.alpha.-hydroxy function would be subject to degradative reaction during solvolysis using a fairly strong acid such as p-toluene sulfonic acid.
To overcome this separation problem, Paaren et al suggested a scheme in which a 1.alpha.-O-acyl cyclovitamin D compound (where acyl may represent any acyl group but not formyl) is solvolyzed in formic acid to produce the 5,6-cis and 5,6-trans mixture of the 1.alpha.-O-acyl-3.beta.-O-formyl-vitamin D compounds.
Reductive or hydrolytic methods for acyl removal are equally convenient and a choice between them would depend on the nature of other functionalities that may be present in the molecule.
www.freepatentsonline.com /4260549.html   (3017 words)

 group | English | Dictionary & Translation by Babylon
Group (sociology), a sub-set of a culture or of a society
Group theory originated with the work of Évariste Galois in 1830, which concerned the problem of when an algebraic equation is soluble by radicals.
Elements that belong to the same group usually show chemical similarities, although the element at the top of the group is usually atypical.
www.babylon.com /definition/group/?uil=English   (679 words)

 3AA-6 to 3AA-10
Groups formed by loss of hydrogen atoms from carbon, sulfur or oxygen atoms (excluding the carboxylic oxygen atoms, which are dealt with under 3AA-9) are named by substituting '-x-yl' for the terminal 'e' of the trivial name, where 'x' is the locant of the atom from which the hydrogen atom has been lost, e.g.
The acyl groups derived from asparagine and glutamine are termed asparaginyl and glutaminyl respectively.
If the hydroxyl group of the 1-carboxyl is replaced by an alkyl group, the name of the ketone formed can use the name of the amino acid by naming the compound as a substituted hydrocarbon, e.g.
www.chem.qmul.ac.uk /iupac/AminoAcid/AA610.html   (1367 words)

The discussion of carboxylic acids, introduced the members of the carboxylic acid family; carboxylic acids, esters, amides, anhydrides, and acyl halides.
Regeneration of the carbonyl group is accompanied by expulsion of the leaving group, either chloride ion, amide ion, or benzoate ion.
The tosylate group was introduced into the molecule by esterification of an alcohol in an earlier step in the synthesis.
www.usm.maine.edu /~newton/Chy251_253/Lectures/Esterification/Esterification.html   (1475 words)

A carboxyl group has a OH group bonded to the carbon of the carbonyl group.
Though a carboxyl group contains both carbonyl and OH groups, this functional group neither behaves as an aldehyde (or ketone) and nor as an alcohol.
An acyl group is the R-CO unit contained in a carboxylic acid.
www.wiu.edu /users/mftkv/Chemistry102/carboxylacylgps.html   (92 words)

 Title of Invention: Fatty acyl reductases
Also considered are amino acid and nucleic acid sequences obtainable from such fatty acyl reductases, which sequences may be used for preparation of recombinant constructs useful for expression of reductase in host cells, which results in the production of fatty alcohols in said cells.
By this invention it is demonstrated that jojoba acyl reductase activity binds to such a column when loaded in a buffer containing approximately 0.2 M NaCl, and more preferred 0.5 M NaCl, or more preferred 0.4 M NaCl, while greater than approximately 85% of other protein passes through or is removed in subsequent washes.
The recombinant construct of claim 1 wherein said reductase is active toward a fatty acyl substrate having a carbon chain of the formula C.sub.2x wherein X is selected from the group 8-12.
www.nal.usda.gov /bic/Biotech_Patents/1994patents/05370996.html   (16107 words)

The residual structure after the hydroxyl group has been removed from the carboxyl group of acids, i.e.
A restriction on the reactivity of a group due to the spatical arrangements of neighboring groups.
This is true whether the protein is transporting the ligand, as hemoglobin does when it carries oxygen, or when the protein performs a chemical reaction on the ligand, as an enzyme does.
www.towson.edu /~sshah/gobglossaryver2.htm   (1022 words)

 InterPro: IPR006162 Phosphopantetheine attachment site
Phosphopantetheine (or pantetheine 4' phosphate) is the prosthetic group of acyl carrier proteins (ACP) in some multienzyme complexes where it serves as a 'swinging arm' for the attachment of activated fatty acid and amino-acid groups [ 1 ].
The DSL sequence is present at the amino terminus of helix II, a domain of the protein referred to as the recognition helix and which is responsible for the interaction of ACPs with the enzymes of type II fatty acid synthesis [ 2 ].
The prosthetic group of acyl carrier protein and the mode of its attachment to the protein.
www.ebi.ac.uk /interpro/IEntry?ac=IPR006162   (3204 words)

 MCE-Summer2000CHEM501-BPgraph   (Site not responding. Last check: 2007-09-30)
Acyl halides react fast with water, a nucleophile, and the hydrolysis process produces the corresponding halogen acid.
Acyl halides are the most reactive of carboxylic acid derivatives.
The carboxyl group is weakly acidic and all carboxylic acids neutralize OH-.RCOOH + NaOH ==> RCOONa + H
www.sas.upenn.edu /~bsalazar/ALKENEbprsch.html   (1346 words)

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