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[No title] base oil soluble) soluble as opposed to one which is highly crosslinked, given the teachings herein, by selecting the appropriate ratio of amino groups to fullerenes and by analyzing the resulting compositions by known techniques for measuring solubility. base oil) soluble polymer unit, described elsewhere in the specification, of the polymer R-N-R', and wherein when R or R' is not a polymer unit it is selected from the group consisting of H and hydrocarbon or oil (e.g. Base oils suitable for use in preparing the lubricating oil compositions of the present invention include natural and synthetic oils well known in the art, e.g., crankcase lubricating oils spark-ignited and compression-ignited internal combustion engines, power transmitting fluids, hydraulic fluids, and power steering fluids. www.godunov.com /Bucky/patents-fulltext/05292444   (5389 words)

Medscape MEDLINE search: Mannich Bases Some mono Mannich bases (1-phenyl-3-amino-1-propanone salts) and bis Mannich bases (1-phenyl-3-amino-2-amino-methyl-1-propanone salts) derived from acetophenone and a few representative quaternary derivatives were synthesised and their cytotoxicity was tested using the brine shrimp bioassay. The effect of the acetophenone derived mono Mannich bases 1-3 and bis Mannich base 7 (bis derivative of compound 3) on cellular glutathione level was investigated in Jurkat cells. This manuscript reports the synthesis of two series of Mannich Bases 3-12 and 21-40 obtained respectively by the reaction of either 2-ethoxycarbonylindoles 1-2 or 5H-pyridazino [4,5b]inoles 17-20 as a substrate with formalin and the appropriate 2 degrees amines under the suitable Mannich conditions. search.medscape.com /uslclient/searchMedline.do?queryText=Mannich+Bases   (1049 words)

Molecular dynamics study of the tautomeric equilibrium in the 4-nitro- and 2,4,6-trichloro- derivatives of ... The adjustment of the force field was based on the application of the atomic charges obtained from fitting to the electrostatic field with the presence of the surrounding solvent modeled by the solvent reaction field. Another interesting feature which was found based on analysis of the radial distribution functions is the fact that there were not any hydrogen bonds between solute molecules and the solvent molecules with participation of the hydrogen from the intramolecular hydrogen bond bridge and with participation of the amine nitrogen (Table 4) for all systems studied. The free energy difference associated with the tautomeric equilibrium in the Mannich bases (2-[N,N-dialkylaminomethyl]-3,4,6-trichlorophenols) in methanol solution was estimated by using the DFT method with solvent reaction field and a combination of the quantum-mechanical energy difference and free energy of solvation provided by an all atom representation of the solvent. www.stat.wvu.edu /~afedorow/ECCC8/index.html   (2927 words)

U.S. Patent: 5162049 - Middle distillate fuels and additives therefor - November 10, 1992 The middle distillate fuel of claim 15 wherein the Mannich base is N-(2,6-dialkyl-4-hydroxybenzyl)hexahydropyrimidine. The middle distillate fuel of claim 15 wherein the Mannich base is N,N-bis(2,6-dialkyl-4-hydroxybenzyl)hexahydropyrimidine. The additive composition of claim 18 wherein R.sub.6 is one or a mixture of tertiary alkyl groups having from 12 to 14 carbon atoms and R.sub.7 is methyl. www.everypatent.com /comp/pat5162049.html   (3083 words)

Selective Ring C-Methylation of Hydroxybenzaldehydes via Their Mannich Bases- [www.rhodium.ws]   (Site not responding. Last check: 2007-10-21) CN reduction of the methiodide of the Mannich base Mannich base 3 was first treated with excess acetic anhydride under reflux to give the diacetate 4. A solution of the Mannich base 3 (104.5 g, 500 mmol), in 500 mL of Ac O was refluxed for 24 h protected from moisture. www.erowid.org /archive/rhodium/chemistry/5-methyl-vanillin.html   (1130 words)

Lubrication Theory and Practice   (Site not responding. Last check: 2007-10-21) Volatility characteristics are essentially inherent in the choice of base oil for a particular type of service and cannot be improved by the use of additive materials. Flow characteristics largely depend on the choice of base oil; however, they can be improved through the use of pour point depressants and viscosity modifiers. The tail section, an oleophilic group, serves as a solubilizer in the base fluid, while the polar group is attracted to contaminants in the lubricant. www.lubrizol.com /LubeTheory/prop.asp   (2397 words)

Mannich reaction - Wikipedia, the free encyclopedia The Mannich reaction is an example of nucleophilic addition of an amine to a carbonyl group followed by elimination of a hydroxyl anion to the Schiff base. The Schiff base is an electrophile which reacts in step two in a second nucleophilic addition with a carbanion generated from a compound containing an acidic proton. In the Mannich reaction ammonia or primary or secondary amines are employed for the activation of formaldehyde. en.wikipedia.org /wiki/Mannich_reaction   (796 words)

Supplemental Topics The trihalo derivatives formed from methyl ketones are then cleaved by base attack at the carbonyl group, reflecting the relative stability of the trihalomethyl anion as a leaving group. The Mannich reaction is similar to a crossed aldol reaction in that a nucleophilic enol-donor forms a carbon-carbon bond to an electrophilic iminium-acceptor. This double Mannich sequence is known as the Robinson-Schopf synthesis in honor of the two chemists who first reported it in the first quarter of the 20th century. www.cem.msu.edu /~reusch/VirtualText/suppmnt3.htm   (4083 words)

LECTURE 5 Mannich Reaction - This is nucleophilic addition reaction of an aldehyde and at least a secondary amine to produce what is known as a schiff base on protonation and elimination of a water molecule. The Schiff base is often stabilized by resonance. The Mannich base formed can readily eliminate the secondary amine to give the synthetic usefulness of the reaction, but when primary amines or ammonia are used the hydrogen on nitrogen atom can participate in a further reaction to give more complex products. www.uiowa.edu /intlinet/unijos/departments/pharmacology/additional.htm   (1340 words)

US Chemical Patent 5182038 Lubricating Oil Additive DC Lawyer Agent - Law Firm McNeely IP Law Attorneys Washington ... Many of the known dispersant/detergent compounds are based on the reaction of an alkenylsuccinic acid or anhydride with an amine or polyamine to produce an alkyl succinimide or an alkenylsuccinamic acid as determined by selected conditions of reaction. It is also known to chlorinate alkenylsuccinic acid or anhydride prior to the reaction with an amine or polyamine in order to produce a reaction product in which a portion of the amine or polyamine is attached directly to the alkenyl radical of the alkenyl succinic acid or anhydride. A concentration range for the additive ranging from about 0.5 to 15 wei-ht percent based on the total weight of the oil composition is preferred with a still more preferred concentration range being from about 1 to 8.0 weight percent. www.patentek.com /CM/Patent/Patent183.asp   (2640 words)

Mannich base - Wikipedia, the free encyclopedia A mannich base is an amine, which is formed in the reaction of electrophilic imine salt and enol of a carbonyl compound (usually ketone or aldehyde). Mannich base is an endproduct in the Mannich reaction, which is is nucleophilic addition reaction of an aldehyde and any primary or secondary amine to produce resonance stabilized schiff base (iminium ion or imine salt). The addition of a carbanion from a CH acidic compound (in the example below diethyl malonate or other enolizable carbonyl compound, amide, carbamate, hydantoin or urea) to the schiff base gives the Mannich base. en.wikipedia.org /wiki/Mannich_base   (172 words)

abstract 13   (Site not responding. Last check: 2007-10-21) Ab initio and density functional calculations are applied to analyse the structure of the Mannich base orrho-dimethylaminomethylphenol with emphasis on a detailed description of the properties of the intramolecular hydrogen bond. The calculated structures of the components, phenol and dimethylbenzylamine, are compared to the geometries of the hydrogen-bonded and open forms of the Mannich base. Additionally, the gas-phase infrared spectra of the Mannich base and of dimethylbenzylamine are presented. www.tbi.univie.ac.at /atbi/abstracts/abstract13.htm   (147 words)

Home Page for Tad Koch Subsequent linking of the amino group of the drug to the amino group of a guanine base of double stranded DNA produces a drug-DNA virtual crosslink. The research group is presently developing the photocrosslinking technology to select and identify photo reactive nucleic acids, from a large combinatorial library of nucleic acids, which will bind and photocrosslink to a target protein and to no other protein in high yield. The protocol is called PhotoSELEX and is based upon the SELEX protocol for the selection of high affinity nucleic acid aptamers from a combinatorial library of nucleic acid sequences. stripe.colorado.edu /~kocht/Home.html   (883 words)

IngentaConnect Total synthesis of (-)-xyloketal D and its enantiomer - Confirmat... The ortho-quinone methide was generated by reaction of an appropriately functionalized Mannich base with methyl iodide. The Mannich base was prepared in one step from 2,4-dihydroxyacetophenone, formaldehyde, and morpholine. La base de Mannich a été préparée en une étape à partir de la 2,4-dihydroxyacétophénone, du formaldéhyde et de la morpholine. www.ingentaconnect.com /content/nrc/cjc/2004/00000082/00000011/art00010   (419 words)

Hydroxy aromatic mannich base condensation products and the use thereof as soot dispersants in lubricating oil ... Low molecular weight Mannich base condensates of hydroxy aromatic compounds, an aldehyde; and an amine, wherein the combined number of substituent carbon atoms does not exceed 80. Such compounds are useful as soot dispersants in lubricating oils when used alone, or in combination with high molecular weight dispersants. Condensats bas de Mannich de poids à faible poids moléculaire des composés aromatiques hydroxy, un aldéhyde ; et une amine, où le nombre combiné d'atomes de carbone de substituant n'excède pas 80. www.patentalert.com /docs/000/z00054109.shtml   (131 words)

Alkyl Halides to Aldehydes and Ketones using 2-Nitropropane/NaOH - [www.rhodium.ws]   (Site not responding. Last check: 2007-10-21) Among a number of routes that could conceivably lead to a phenyl-substituted α-butylamine was a Mannich reaction involving benzaldehyde, dimethylamine and 2-nitropropane. When this reaction was attempted, no Mannich base formed. The expected reaction, forming Mannich base, should have been carbon alkylation of the active hydrogen compound, 2-nitropropane, by the cation 1 resulting from the interaction of benzaldehyde and dimethylamine. www.erowid.org /archive/rhodium/chemistry/halide.carbonyl.html   (2128 words)

Agidol-3 (Mannich base) (eng) It is used as a thermopolymerization inhibitor, non-staining antioxidant for white colored rubbers based It is used as an inhibitor for gasoline and diesel fuel oxidation, it permits to prolong AVAILABILITY: Mannich base is available in laminated paper sacks of 15 kg. www.bashnet.ru /~spp/pre07.htm   (117 words)

Sequenced Reactions Applied to Natural Product Synthesis For instance, the first reported sequenced reaction is the Mannich reaction. Under the reaction conditions, a hydrochloride salt of a secondary amine 3 is stirred with acetophenone 1 and formaldehyde 2 to give an intermediate iminium salt 4. The earliest reported application of a sequenced transform toward the synthesis of a natural product was based on a tandem Mannich-decarboxylation reaction. www.chem.umn.edu /studsem/abstract9697/judd4897/judsem.html   (1012 words)

DMS | Uses Methylated quaternary salts also serve as flocculants, which are used in water treatment, such as in sewage sludge control. An example is a quarternized Mannich base of low molecular weight polyacrylamides:3 In actual practice, not all of the amide groups of the polyacrylamide are used in the Mannich reaction. www.dupont.com /dms/uses/commercial.html   (269 words)

Organic Lecture Ketones + Amines etc   (Site not responding. Last check: 2007-10-21) This is usually done in the presence of a weak base. However the hydyoxylammonium salt is inactive as there is no lone pair of electrons on the nitrogen to donate and there is a positive charge on the nitrogen. This reaction can be considered to be a more general reaction; the linking of a carbanion site (enolate (or phenolate)) with an aldehyde and an amine. freon.chem.swin.edu.au /~marg/hes2520/orgacids_7_8.html   (279 words)

Doxorubicin-formaldehyde conjugates targeting {alpha}v{beta}3 integrin -- Burkhart et al. 3 (12): 1593 -- Molecular ... based on the known half-life for the trigger (9). Doxsaliform: a novel N-Mannich base prodrug of a doxorubicin formaldehyde conjugate. Free radicals and anticancer drug resistance: oxygen free radicals in the mechanisms of drug cytotoxicity and resistance by certain tumors. mct.aacrjournals.org /cgi/content/full/3/12/1593   (5814 words)

New quinoline di-Mannich base compounds with greater antimalarial activity than chloroquine, amodiaquine, or ... New quinoline di-Mannich base compounds with greater antimalarial activity than chloroquine, amodiaquine, or pyronaridine -- Kotecka et al. New quinoline di-Mannich base compounds with greater antimalarial activity than chloroquine, amodiaquine, or pyronaridine Of the 12 Mannich bases tested, 8 were aac.asm.org /cgi/content/abstract/41/6/1369   (300 words)

Open Research Online - Amidomethylation of amodiaquine: antimalarial N-Mannich base derivatives Lopes, Francisca and Capela, Rita and Gonçaves, Jose O. and Horton, Peter N. and Hursthouse, Michael B. and Iley, Jim and Casimiro, Catarina M. and Bom, Joana and Moreira, Rui (2004) Amidomethylation of amodiaquine: antimalarial N-Mannich base derivatives. Novel N-Mannich base-type derivatives of the antimalarial drug amodiaquine were synthesised by reaction with tertiary amodiaquine; malaria; Mannich basel; Amodiaquine; Amidomethylation; antimalarial oro.open.ac.uk /3989   (125 words)

Journal of the Chemical Society C: Organic articles Mechanism of pyrazoline formation from the reactions of substituted hydrazines and Mannich bases These substituted hydrazones do not display hydrazine anchimerism to form pyrazolines, probably because they exist in the wrong geometric form. The suggested mechanism for pyrazoline formation involves elimination from the Mannich base to form a vinyl ketone, which then forms a hydrazone (of the right configuration); subsequently this cyclises to the pyrazoline. www.rsc.org /Publishing/Journals/J3/article.asp?doi=J39710000080   (102 words)

The Mannich Base NC1153 Promotes Long-Term Allograft Survival and Spares the Recipient from Multiple Toxicities -- ... The Mannich Base NC1153 Promotes Long-Term Allograft Survival and Spares the Recipient from Multiple Toxicities -- Stepkowski et al. The Mannich Base NC1153 Promotes Long-Term Allograft Survival and Spares the Recipient from Multiple Toxicities that a Mannich base, NC1153, blocked IL-2-induced activation www.jimmunol.org /cgi/content/abstract/175/7/4236   (292 words)

Grease composition containing borated alkoxylated alcohols (US4780227)   (Site not responding. Last check: 2007-10-21) Metal oxide paste dispersions and use as curing agents Borated derivatives of oil-soluble Mannich bases in combination with coadditive hydrocarbons are flow improvers for middle distillate fuel oils Hydrocarbon-soluble epoxidized fatty acid esters as lubricity modifiers for lubricating oils www.delphion.com /details?pn10=US04780227   (511 words)

pyronaridine   (Site not responding. Last check: 2007-10-21) This drug is a naphthyridin derivative and mannich base synthesised in China. Its structure is similar to mepacrine and amodiaquine (drugs which are now longer used for the treatment of malaria), but it is effective against multi-resistant falciparum parasites. Current Treatments for Malaria last edited on 4 May 2004 at 5:57 am by 217.23.231.70 pbl.cc.gatech.edu /mindy/1328   (54 words)

New Page 2 An expeditious solventless synthesis of novel Mannich bases of thiobarbiturates and barbiturates using montmorillonite clay under microwaves are herein described. This methodology eliminates the use of excess of solvent during the course of reaction. Key words: Thiobarbiturates, Barbiturates, Mannich base, Montmorillonite, Microwave, acta.chem-soc.si /52/52-1-88.htm   (136 words)

Imine - Wikipedia, the free encyclopedia Addition reactions with primary amines give stable imines but with an aryl group or certain stabilizing alkyl substituents on nitrogen, (the imine is then called a Schiff base) the imine is truly stable, see alkylimino-de-oxo-bisubstitution. note that addition of carbonyl compounds to the salt of an amine yields the corresponding Mannich base en.wikipedia.org /wiki/Imine   (387 words)

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