144-49-0

Asymmetric cyclocondensation of N-sulfonylimines with fluoroacetic acid promoted by isothiourea catalyst HBTM-2 generates 3-fluoro-β-lactams with high enantio- and diastereoselectivity. These reactive compounds are opened with alcohols or amines to produce the corresponding α-fluoro-β-amino acid derivatives in moderate yields.

The decomposition of perfluorodiethyl ether on alumina has been studied at 300 and 500 K by transmission infrared spectroscopy using excess ether under high-pressure conditions.It was found in this study that the reaction products include trifluoro-, difluoro-, and monofluoroacetate, fluoroformate, alkyl acetate, and alkyl formate.The initial formation of trifluoroacetate probably results from a nucleophilic attack at the α-carbon of the ether by a surface oxygen anion.Subsequently, fluorine atoms, abstracted by coordinately unsaturated (cus) aluminum atoms, are replaced by hydrogen atoms donated by isolated surface hydroxyls.There is also evidence that fluoroalkene and fluoroalkyne resulted from the decomposition of initial surface adsorbates.

The invention discloses a compound for inhibiting three-mutant epidermal growth factor receptor tyrosine kinase, and is characterized in that the structural formula is as follows. Among them: Substituent R1 . One of: Substituent R2 . One of: The substituent X is H or Cl. Substituent R3 To H. One of the following.

Fluoroacetamide (FAM) is a small (77 Da) and highly toxic chemical, formerly used as a rodenticide and potentially as a poison by terrorists. Poisoning with FAM has occurred in humans, but few reliably rapid detection methods and antidotes have been reported. Therefore, producing a specific antibody to FAM is not only critical for the development of a fast diagnostic but also a potential treatment. However, achieving this goal is a great challenge, mainly due to the very low molecular weight of FAM. Here, we design two groups of FAM haptens for the first time, maximally exposing the fluorine or amino groups, with the aid of linear aliphatic or phenyl-contained spacer arms. Interestingly, whereas the hapten with fluorine at the far end of the hapten did not induce an antibody response to FAM, the hapten with an amino group at the far end and phenyl-contained spacer arm triggered a significantly specific antibody response. Finally, a monoclonal antibody (mAb) named 5D11 was successfully obtained with an IC50 value of 97 μg mL?1 and negligible cross-reactivities to the other nine functional and structural analogs.

A method for preparing a fluorinated organic compound (II) from an organic compound (I) comprising at least one nucleofugal group Nu, and also a preparation of different specific organic compounds, in particular a fluoro-methylpyrazole compound. The method comprises: a reaction, in the presence of water, of the organic compound (I) and at least one salt providing at least one fluoride anion; and a replacement of at least one nucleofugal group Nu of the compound (I) with a fluorine atom, in order to obtain the fluorinated organic compound (II).

Fluorinated analogues of bioactive amino sugars are of high interest in medicinal chemistry. We developed a straightforward synthetic route towards this class of carbohydrates by applying a titanium-mediated aldol addition. Thus, two-carbon chain elongations of serine- and threonine-derived aldehydes with a chiral fluoroacetyl-oxazolidinone could be achieved in good yields and excellent diastereoselectivities to generate a fluorohydrin-containing carbon skeleton. A short deprotection sequence subsequently furnished the pyranoid forms of various 4-amino-2-fluoropentoses and -hexoses, respectively. The versatility of this strategy was demonstrated by the stereoselective synthesis of naturally abundant 4-amino-4-deoxyarabinose and 4-amino-4,6-dideoxygalactose (tomosamine). 4-Amino-2-fluoropentoses and -hexoses were prepared through two-carbon chain elongations by Ti-mediated aldol additions of serine- and threonine-derived amino aldehydes to fluoroacetyl-ephedrine-oxazolidinone. Excellent stereoselectivities were attained for matched-case fluorohydrins, which were deprotected in a short sequence. Copyright

The leaving group ability (nucleofugality) of fluoroacetate, chloroacetate, bromoacetate, dichloroacetate, trifluoroacetate, trichloroacetate, heptafluorobutyrate, formate, isobutyrate, and pivalate have been derived from the solvolysis rate constants of the corresponding X,Y-substituted benzhydryl carboxylates in 60 % and 80 % aqueous acetonitrile and 60 % aqueous acetone, applying the LFER equation: log k = sf(Ef + Nf). The experimental barriers (ΔG?,exp) for solvolyses of 11 reference dianisylmethyl carboxylates in these solvents correlate very well (r = 0.994 in all solvents) with ΔG?,model of the model σ-assisted heterolytic displacement reaction of cis-2,3-dihydroxycyclopropyl trans-carboxylates calculated earlier. Linear correlation observed between the log k for the reference dianisylmethyl carboxylates and the sf values enables estimation of the reaction constant (sfestim). Using the ΔG?,exp vs. ΔG?,model correlation, and taking the estimated sfestim, the nucleofugality parameters for other 34 aliphatic carboxylates have been determined in 60 % and 80 % aqueous acetonitrile and 60 % aqueous acetone. The most important variable that determines the reactivity of aliphatic carboxylates in aprotic solvent/water mixtures is the inductive effect of the group(s) attached onto the carboxylate moiety.

The present invention provides rotenone analogs and methods of making and using them. Labeled with single photon and positron emitting isotopes, the rotenone analogs of the present invention are useful in, for example, clinical imaging applications as tracers to measure cardiac blood flow and detect regions of ischemia.

The invention relates to acetyl 2-hydroxy-1,3-diaminospirocyclohexanes and derivatives thereof that are useful in treating diseases, disorders, and conditions associated with amyloidosis. Amyloidosis refers to a collection of diseases, disorders, and conditions associated with abnormal deposition of A-beta protein.

The invention relates to acetyl 2-hydroxy-1,3-diaminospirocyclohexanes and derivatives thereof that are useful in treating at least one disease, disorder, and condition associated with amyloidosis. Amyloidosis refers to a collection of diseases, disorders, and condition associated with abnormal deposition of A-beta protein.

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Fluoroacetaldehyde is converted to fluoroacetate and 4-fluorothreonine in Streptomyces cattleya indicating that it is the biosynthetic precursor of both of these secondary metabolites.

A compound having the formula: STR1 wherein R is a straight chain or branched chain lower alkyl, cyclic lower alkyl, lower alkenyl (except for 1-carboxy-1-vinyl), lower alkynyl, aralkyl, phenyl or 2-pyrrolidon-3-yl group which may be substituted, and Q is STR2 (wherein R1 is a hydrogen atom or an acetyl group, R2 is a hydrogen atom, a carboxyl group or a carboxymethyl group, Y is a sulfur atom or an oxygen atom, Z is a sulfur atom, an oxygen atom or an imino group which may be substituted by a lower alkyl group); or a pharmaceutically acceptable salt, physiologically hydrolyzable ester or solvate thereof.

Photoreduction in hexamethylphosphortriamide was found to be an efficient method to selectively reduce C-F bonds α to the carboxyl group of alkyl perfluoroesters.The reation proceeds by photoinduced electronic transfer from the excited phosphoramide.Conditions were found to remove selectively one fluorine and the reaction was applied to the synthesis of alkyl 2-hydro perfluoroesters.

Measurements of the gas phase proton transfer equilibrium : AH + B- = A- + BH with a pulsed electron high pressure mass spectrometer (PHPMS) lead to ΔG01 and ΔH01 data.These relative acidities are converted to the absolute acidities : AH = A- + H+ by calibration of the relative ΔG01 and ΔH01 scale to the known values for ΔG01 and ΔH01 of a reference compound (HCl).Earlier determinations that included 16 aliphatic AH are extended in the present work and provide data for 47 aliphatic carboxylic acids.These include halogen, OH, CH3O, C2H5O, PhO, and NH2 substituted acetic acids, and halogen substituted, unsaturated, and cyclic RCO2H of higher carbon number.The effects of the various substituents on the gas phase acidity are briefly examined.Key words: acidities in gas phase, proton transfer equilibria, ion-molecule equilibria, mass spectrometry.

The reaction of dimethylsulfoxonium methylide with α-fluoro α-ethylenic esters: R1-CH=CF-COOR' leads to the formation of β-keto-sulfoxonium ylides 3: R1CH=CF-CO=C-H-S+(O)(CH3)2.Reaction of ylides 3 with anhydrous HCl, at room temperature, provides β-keto γ,γ-fluoro-ethylenic sulfoxonium salts, whose decomposition, at high temperatures, leads to the formation of fluorinated chloromethyl-ketones: R1-CH=CF-CO-CH2Cl, which are not available by other methods.

The influence of polar substituents on the hydrolysis of acetic acid esters is in perfect agreement with the predictions of an electrostatic model of the activated complex both for alkaline and neutral hydrolysis.Acid hydrolysis involves the counteraction of two polar effects and is not accessible to this model.In agreement with this result, the steric parameter ES of Taft's linear energy relationship is not helpful for the discussion of steric effects of polar substituents in ester hydrolysis reactions. - Keywords: Ester hydrolysis / Neutral ester hydrolysis / Polar substituent effect / Electrostatic reaction model

Date are reported for the multiphoton, pulsed, infrared laser-induced unimolecular reactions of a series of organic esters.The dependence of the reaction probability and absorption cross sections on the laser fluence, laser frequency, reactant pressure, and bath gas pressure was determined for ethyl acetate, ethyl fluoroacetate, ethyl acrylate, n-butyl acetate, sec-butyl acetate, and ethyl 2-bromopropionate.The extent of collisional energy transfer from excited ester molecules to cold molecules was characterized by a thermal monitor molecule; collisional energy transfer leading to reaction of the monitor was negligible at pressures -2-10-4 with slopes of 4-6.At high fluences P(Φ) values asymptotically approach constant values between 0.6 and 1.0.For ethyl acetate and ethyl fluoroacetate the reacion probability for the same amount of absorbed energy was dependent on laser frequency and fluence; this is evidence that only a certain, fluence-dependent, fraction of molecules absorb the laser energy.Addition of bath gas reduced the reaction probabilities, especially at low laser fluence, indicating that postpulse reaction was very important for P(Φ) 0.1.

The reactions of some α-aminoacids with excess sodium nitrite in polyhydrogen fluoride-pyridine are described.

Anchimerically assisted rearrangement, observed in the fluorination of some α-amino acids with 70:30 (w/w) hydrogen fluoride/pyridine (by weight) in the presence of NaNO2, is substantially or fully suppressed by using the less acidic reagent 48:52 (w/w) hydrogen fluoride/pyridine.

The nitrosation of α-amino acids in hydrogenfluoride/pyridine was reinvestigated.In contrast to recent reports it was found that this reaction takes place either with entire (phenylalanine, tyrosine, threonine) or partial (valine, isoleucine) rearrangement to yield β-fluorocarboxylic acids.Glycine, alanine and α-amino-butanoic acid were converted exclusively into the α-fluorocarboxylic acids.The substitution of the amino group takes place with stereochemical retention as revealed by NMR. examination of the 2-fluoro-3-methylpentanoic acids obtained from L-isoleucine and D-alloisoleucine, respectively.