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In this letter, we successfully explored a cascade Pd/Cu-catalyzed intermolecular C(sp3)-H arylation of amides and intramolecular C-N coupling reaction. This method provides a one-pot strategy to synthesize 3,4-2H-quinolinone with good regioselectivity of C-H arylation and C-N coupling from C-I and C-X bonds from readily available starting materials.

Palladium-catalyzed arylation of unactivated β-C(sp3)-H bonds in carboxylic acid derivatives with aryl iodides is described for the first time using 2-amino-5,6-difluorophenyl-1H-pyrazole as an efficient and readily removable directing group. Two fluoro groups are installed at the 5- and 6-position of the anilino moiety in 2-aminophenyl-1H-pyrazole, clearly enhancing the directing ability of the auxiliary. In addition, the protocol employs Cu(OAc)2/Ag3PO4 (1.2/0.3) as additives, evidently reducing the stoichiometric amount of expensive silver salts. Furthermore, this process exhibits high β-site selectivity, compatibility with diverse substrates containing α-hydrogen atoms, and excellent functional group tolerance.

The stereochemistry of 2′-methylbutyrophenone oxime, the rates of ortho-palladation of its E- and Z-isomers, and catalytic activity of the respective Pd complexes were studied. The full stereoisomeric composition of oximes was established for the first time by means of supercritical fluid chromatography on chiral polysaccharide column. It was shown that enantiomeric excesses of both E/Z-isomers of (S)-2′-methylbutyrophenone oxime (1S) and (R)-2′-methylbutyrophenone oxime (1R) were equal to 92 ± 2. The cyclopalladation study revealed that while E-isomer is ortho-palladated very quickly its Z-counterpart does not enter this reaction. However, upon coordination to Pd(II), Z-oxime slowly isomerizes into E-form with fast subsequent cyclopalladation, so it was possible to perform ortho-palladation of E-oxime in kinetic resolution mode with removal of unreacted Z-oxime. Comparatively rare cis-structure of cyclopalladated oxime dimer was proved by means of single-crystal X-ray study. For the first time, it was shown that ortho-palladated chiral oximes behave as enantioselective catalyst in the hydrolysis of chiral esters.

Pd-catalyzed β-C-H functionalizations of carboxylic acid derivatives using an auxiliary as a directing group have been extensively explored in the past decade. In comparison to the most widely used auxiliaries in asymmetric synthesis, the simplicity and practicality of the auxiliaries developed for C-H activation remains to be improved. We previously developed a simple N-methoxyamide auxiliary to direct β-C-H activation, albeit this system was not compatible with carboxylic acids containing α-hydrogen atoms. Herein we report the development of a pyridine-type ligand that overcomes this limitation of the N-methoxyamide auxiliary, leading to a significant improvement of β-arylation of carboxylic acid derivatives, especially α-amino acids. The arylation using this practical auxiliary is applied to the gram-scale syntheses of unnatural amino acids, bioactive molecules, and chiral bis(oxazoline) ligands.

A Pd(II)-catalyzed sulfonylation of unactivated C(sp3)-H bonds with sodium arylsulfinates using an 8-aminoquinoline auxiliary is described. This reaction demonstrates excellent functional group tolerance with respect to both the caboxamide starting material and the sodium arylsulfinate coupling partner, affording a broad range of aryl alkyl sulfones. Moreover, the late-stage modification of complex molecules was achieved via this sulfonylation protocol.

A novel palladium catalyzed hydroxylation of unactivated aliphatic C(sp3)-H bonds was successfully developed. Different from conventional methods, water serves as the hydroxyl group source in the reaction. This new reaction demonstrates good reactivity and broad functional group tolerance. The C-H hydroxylated products can be readily transformed into various highly valuable chemicals via known transformations. Based on experimental and theoretical studies, a mechanism involving the Pd(ii)/(iv) pathway is proposed for this hydroxylation reaction.

Acylcarnitines are intermediates of fatty acid and amino acid oxidation found in tissues and body fluids. They are important diagnostic markers for inherited diseases of peroxisomal and mitochondrial oxidation processes and were recently described as biomarkers of complex diseases like the metabolic syndrome. Quantification of acylcarnitine species can become challenging because various species occur as isomers and/or have very low concentrations. Here we describe a new LC-MS/MS method for quantification of 56 acylcarnitine species with acyl-chain lengths from C2 to C18. Our method includes amino acid-derived positional isomers, like methacrylyl-carnitine (2-M-C3:1-CN) and crotonyl-carnitine (C4:1-CN), and odd-numbered carbon species, like pentadecanoyl-carnitine (C15:0-CN) and heptadecanoyl-carnitine (C17:0-CN), occurring at very low concentrations in plasma and tissues. Method validation in plasma and liver samples showed high sensitivity and excellent accuracy and precision. In an application to samples from streptozotocin-treated diabetic mice, we identified significantly increased concentrations of acylcarnitines derived from branched-chain amino acid degradation and of odd-numbered straight-chain species, recently proposed as potential biomarkers for the metabolic syndrome. In conclusion, the LC-MS/MS method presented here allows robust quantification of isomeric acylcarnitine species and extends the palette of acylcarnitines with diagnostic potential derived from fatty acid and amino acid metabolism.

Chemical fractionation of the southern Australian marine sponge Phoriospongia sp. (CMB-03107) yielded phorioadenine A (1) as a nematocidal agent and the first reported example of a 6-N-acyladenine natural product. The structure of 1 was confirmed by spectroscopic analysis and the chemical synthesis of racemic (1a) and enantiomeric (1b) analogues. HPLC-ESIMS analysis of the crude sponge extract with comparisons to the synthetic 6-N-acyladenosine 2a provided evidence that the biosynthetically related adenosine, phorioadenosine A (2), was present as a trace co-metabolite. The rare starfish metabolite asterubine (3) was also isolated as a co-metabolite, and its structure confirmed by spectroscopic analysis and chemical synthesis. Biological investigations confirmed that natural products 1-3 and synthetic analogues 1a-e and 2a were not cytotoxic to multiple mammalian cancer cell lines, or Gram-positive or -negative bacteria. Nematocidal activity (inhibition of larval development of Haemonchus contortus) detected in the Phoriospongia sp. extract was attributed to 1 (LD9931 μg/mL), with preliminary structure-activity relationship investigations confirming the importance of the N-acyl side chain.

9-Methylacridine was identified as a generally effective ligand to promote a Pd(II)-catalyzed C(sp3) - H and C(sp2) - H alkylation of simple amides with various alkyl iodides. This alkylation reaction was applied to the preparation of unnatural amino acids and geometrically controlled tri- and tetrasubstituted acrylic acids.

Reduction of (S)-N-(2-bromoallyl)-N-(tert-butyl)-2-methyl-3- phenylpropanamide with tributyltin hydride provides (3S,4S)-3-benzyl-1-(tert- butyl)-3,4-dimethylpyrrolidin-2-one with about 80% retention of chirality at the stereocenter adjacent to the amide carbonyl group. This memory of chirality is suggested to occur by transfer of chirality from a stereocenter to an axis, then from the axis back to a new stereocenter.

Plinabulin (11, NPI-2358) is a potent microtubule-targeting agent derived from the natural diketopiperazine "phenylahistin" (1) with a colchicine-like tubulin depolymerization activity. Compound 11 was recently developed as VDA and is now under phase II clinical trials as an anticancer drug. To develop more potent antimicrotubule and cytotoxic derivatives based on the didehydro-DKP skeleton, we performed further modification on the tert-butyl or phenyl groups of 11, and evaluated their cytotoxic and tubulin-binding activities. In the SAR study, we developed more potent derivatives 33 with 2,5-difluorophenyl and 50 with a benzophenone in place of the phenyl group. The anti-HuVEC activity of 33 and 50 exhibited a lowest effective concentration of 2 and 1 nM for microtubule depolymerization, respectively. The values of 33 and 50 were 5 and 10 times more potent than that of CA-4, respectively. These derivatives could be a valuable second-generation derivative with both vascular disrupting and cytotoxic activities.

The present invention concerns a family of sulfanilamide derivatives of formula (I) as anticonvulsant agents, where R1 is selected from optionally substituted C4-C9 alkyl, optionally substituted C6-C10 aryl, optionally substituted C6-C10 alkylenearyl and optionally substituted C5-C10 heteroaryl; R2 is selected from -H and optionally substituted C1-C6 alkyl; each of R3 and R4, independently of each other, is selected from -H, optionally substituted C1-C6 alkyl, optionally substituted C6-C10 aryl and optionally substituted C5-C10 heteroaryl; n is 0, 1, 2, 3 or 4. The derivatives have been prepared and their anticonvulsant profile was evaluated for the control of epileptic seizures.

The present invention relates to the use of novel macrocyclic compounds of Formula I, wherein the variables Q, Q1, Q2, Q3, and Q4 are defined as described herein, which inhibit JAK and are useful for the treatment of auto-immune and inflammatory diseases.

Three new glycosides, 7-O-tigloylsecologanol (1), 7-O-tigloylsecologanolic acid (2), and 3'-O-[(2S)-2-methylbutanoyl]henryoside (3), together with seven known ones, were isolated from the leaves of Viburnum plicatum Thunb. var. tomentosum Miq. Their structures were established on the basis of spectral and chemical data.

Despite the availability of 14 new antiepileptic drugs (AEDs), about 30% of epileptic patients are not seizure-free. Consequently there is substantial need to develop new effective AEDs. A novel class of aromatic amides composed of phenylacetic acid or branched aliphatic carboxylic acids, with five to nine carbons in their carboxylic moiety, and aminobenzenesulfonamide were synthesized and evaluated in the anticonvulsant rat-maximal electroshock (MES) and subcutaneous metrazol seizure (scMet) tests. Fourteen of the synthesized amides had an anticonvulsant ED50 of 50 values of 7.6, 9.9, and 9.4 mg/kg and remarkable protective index (PI = TD 50/ED50) values of 65.7, 50.5, and 53.2, respectively. These potent sulfanylamides caused neural tube defects only at doses markedly exceeding their effective dose. The anticonvulsant properties of these compounds make them potential candidates for further development as new, potent, and safe AEDs.

Ethnopharmacological relevance: Hofmeisteria schaffneri (Asteraceae) is a medicinal plant widely commercialized in the most important Markets of Mexico City for the treatment of gastro-intestinal complaints and skin afflictions. Aim of the study: The main goals of this study were to establish the potential acute toxicity and the antinociceptive activity in animal models of several preparations and compounds from Hofmeisteria schaffneri. Materials and methods: The aqueous and organic extracts as well as the essential oil of Hofmeisteria schaffneri were prepared by infusion, maceration and hydrodistillation, respectively. Investigation of the acute toxicity was accomplished by the Lorke method. The antinociceptive effect was assessed using the writhing and the hot plate tests. Natural compounds were isolated by standard phytochemical procedures. In addition, a few thymol esters were prepared by chemical synthesis. The stability of natural and synthetic esters was qualitatively analyzed by measuring their susceptibility to hydrolysis by pig liver estearase and mouse plasma at 37°C. Results: The LD50 for each preparation tested was higher than 5000mg/kg revealing that they were not toxic to mice after exposure for short space of time. On the other hand, the extracts showed significant antinociceptive effect when tested in the hot plate model. The most active natural product as antinociceptive agent was hofmeisterin III (1) which also was the most stable in the stability study. Its pharmacological effect seems to be partially mediated by an opioid mechanism since naloxone inhibits its action. Using compound 1 as a lead molecule, several synthetic thymol esters were prepared and only compounds 13, 15 and 17 were antinoceptive at the dose of 1mg/kg. Conclusions: The present investigation provided evidence of the efficacy of several preparations of Hofmeisteria schaffneri as antinociceptive agents. The most active preparation was the essential oil which contained large amount of hofmeisterin III (1) and other thymol derivatives. Some novel synthetic analogs of hofmeisterin III with antinociceptive properties were discovered. The nature of the ester chain of these analogs did not have a clear impact on the antinociceptive activity. The phyto-preparations analyzed in this study were not toxic to mice according to the Lorke's test; therefore considering their long term use of the plant they might be secure for human consumption.

Valproic acid (VPA, 1) is a major broad spectrum antiepileptic and central nervous system drug widely used to treat epilepsy, bipolar disorder, and migraine. VPA's clinical use is limited by two severe and lifethreatening side effects, teratogenicity and hepatotoxicity. A number of VPA analogues and their amide, N-methylamide and urea derivatives, were synthesized and evaluated in animal models of neuropathic pain and epilepsy. Among these, two amide and two urea derivatives of 1 showed the highest potency as antineuropathic pain compounds, with ED50 values of 49 and 51 mg/kg for the amides (19 and 20) and 49 and 74 mg/kg for the urea derivatives (29 and 33), respectively. 19, 20, and 29 were equipotent to gabapentin, a leading drug for the treatment of neuropathic pain. These data indicate strong potential for the above-mentioned novel compounds as candidates for future drug development for the treatment of neuropathic pain. 2009 American Chemical Society.

The total synthesis of racemic γ-indomycinone (rac-3) was achieved by Baker-Venkataraman rearrangement of ester 11 to the diketone 12, acid-catalyzed cyclization to the anthrapyranone 13, followed by methyl ether cleavage and acetylation to 16, selective bromination of the branched side chain with simultaneous SN1-type hydroxy substitution to 23 and transesterification to rac-3. The corresponding γ-indomycin-one 11-methyl ether (rac-20) was prepared in a similar reaction sequence. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.

A Wittig reaction between (+)-3 and the phosphoranylide derived from the bithiazole-type phosphonium iodide [(±)-4] using lithium bis(trimethylsilyl)amide afforded a diastereomeric mixture of the (+)-(4R,5S,6E,14R)- and (4R,5S,6E,14S)-melithiazols G (1), whose NMR spectral data were identical with those of the natural product (1). The antifungal activity of the synthetic diastereomeric mixture of melithiazols G (1) against the phytopathogenic fungus, Phytophthora capsici, was evaluated by using a paper disc assay method.

The alkylation of the lithium enolate of (IR)-3-endo-(p-methoxybenzyl)isobornyl propionate in THF gives predominantly the (R)-2-methylalkanoic esters in de's of 25-42%. The structure of the alkyl halide does not affect the outcome, although the most reactive halides give the greatest de levels. The formation of the enolate in THF-HMPA reverses the stereochemistry of the alkylation with ethyl bromide from 42% R to 23% S. The stereochemistry of the reaction is interpreted in terms of a conformational shift on deprotonation of the ester.

Readily preparable morpholine amides hitch in good yields with organocerium reagents to produce ketones. Even in the presence of substrates and reagents with high steric hindrance, the organometallic compounds prepared from dry cerium(III) chloride and organomagnesium or organolithium compounds at -78 degrees C add cleanly to morpholine amides. The low cost of starting materials makes this new scheme of synthesis very interesting for the preparation of biologically important pheromones.

Natural 1-amidopyrrolizidines, absouline and laburnamine, were synthesized via stable pyrrolizidin-1-one hydrobromide. Amides, ester derivatives and aminopyrrolidinoimidazole analogues were also prepared and their biological activities tested. (C) 2000 Elsevier Science Ltd.

A new chiral anisotropic reagent, phenylglycine methyl ester (PGME), developed for the elucidation of the absolute configuration of chiral α,α- disubstituted acetic acids, has turned out to be applicable to other substituted carboxylic acids, such as chiral α-hydroxy-, α-alkoxy-, and α- acyloxy-α,α-disubstituted acetic acids, as well as to chiral β,β- disubstituted propionic acids. Because a carboxylic moiety is convertible from other functional groups, e.g., ozonolysis of an olefin and oxidative cleavage of a glycol, the present findings can expand the utility of the PGME method to the absolute configuration determination of various types of organic compounds, even those which initially lack oxygen functions. Several examples of the combination of chemical reactions and the PGME method are described.

Four α,α,α-trisubstituted acetophenones ((1):R1=R2=R3=CH3; (2):R1=R2=CH3, R3=CH2CH3; (3):R1=R2=CH3, R3=CH2Ph; (4):R1=CH3, R2=CH2CH3, R3=CH2Ph) were prepared.Ketones (1)-(4) were treated with aluminium chloride to induce rearrangement to alkyl ketones.The phenyl ketones behaved as follows: (1) gave 3-methyl-3-phenylbutan-2-one (7), (2) gave 3-methyl-3-phenylpentan-2-one (8) and 2-methyl-2-phenylpentan-3-one (9), (3) gave 3-methyl-3,4-diphenylbutan-2-one (10) and 3-methyl-1,3-diphenylbutan-2-one (11), and (4) gave 3-methyl-1,3-diphenylpentan-2-one (12), 2-methyl-1,2-diphenylpentan-3-one (13) and 3-benzyl-3-phenylpentan-2-one (14).A tentative mechanism for the rearrangement is proposed.

This invention provides novel biphenyl compounds represented by the following general formula (I): STR1 (wherein R is an alkyl group, A is selected from the single bond, --COO--, --OCO--, --OCOO-- and --CO--, and each of m and n is an integer of 1 or more, provided mn), optically active bodies thereof, liquid crystal compositions containing at least one of these compounds, light switching elements comprising at least one of the above compounds as a constituent element, and a method of producing the compound.

The separation of diastereomeric phenylglycinolamides of 2-methylbutyric acid by means of MPLC yields the pure enantiomers of the acid, from which (R,Z)- and (S,Z)-14-methyl-8-hexadecenal (1) (trogodermal) can be obtained.

2-Hydroxy-2-alkyl-1,3-dioxolanes T are the cyclic intermediates of the degenerate intramolecular ester interchange reactions of ethylene glycol monoalkanoates A, in which alkanoyl groups transfer from one end of ethylene glycol to the other.This study reports equilibrium constants for the cyclization AT to the tetrahedral intermediate stage with 10 alkanoate derivatives.These equiilibrium constants, which when written as / are all large (1 E7-1 E9) in favor of the ring opened form, were obtained as the ratio of rate constants for equilibration occuring with H+ catalysis.Rate constants for the ring opening of T were directly measured through a study of kinetics of the hydrolysis of 2-methoxy-2-alkyl-1,3-dioxolane ortho esters.These hydrolysis proceed via T, and under acid conditions the breakdown of this intermediate is rate-limiting.Rate constants in the ring-closing direction were obtained by preparing HOCH2CD2OOCR and, with the use of 1H NMR spectroscopy, measuring the kinetics of isomerization to an equilibrium mixture with RCOOCH2CD2OH.The reaction under investigation is an intramolecular analogue of H+-catalyzed alkanoate ester hydrolysis, whose rate constant define the steric substituent parameter Es.The ring-closure rate constant for A -> T do show an excellent correlation with Es.However, the rate constants for ring-opening T -> A and the overall equilibrium constant are badly correlated, showing quite different behavior for series with α and β branching in the alkyl group.Thus, for this system the Es parameter does not correlate free energy differencies between the acyl derivative and tetrahedral intermediate.It is only the free energy differences between the acyl form and the transition state leading to the intermediate that fit Es.

Radicals generated by photolysis (W light) of esters derived from N-hydroxy-2-thiopyridone react with electrophilic isocyanides 2a and (in the presence of trifluoroacetic acid) 2b to give adducts of type 3.Convenient reaction procedures have been worked out to hydrolyse the adducts to amides of type 5, from which the original acid can be regenerated under mild conditions.The three important acids oleic, linoleic and arachidonic have all given smooth reactions.In suitable examples, quantitative evolution of carbon dioxide and incorporation of 13C without dilution have been demonstrated.This reaction sequence will be useful for the labelling in the carboxyl group of prostaglandins, leukotrienes, and the side chain carboxyls of peptides.

Attempts to prepare 2-bromo-2,4-dimethyl,3-trimethylsiloxy 3-pentene reacting lithium diisopropylamide (LDA) with 2-bromo-2,4-dimethyl-3 pentanone have revealed two new reactions.After a few minutes quantitative yields are obtained of either the dehalogenated ketone (after hydrolysis) or the trimethylsilyl enol ether (after addition of trimethylsilyl chloride).These reactions are general and have been extended to other α-monobromoketones and α,α'-dibromoketones.In the latter case, the reaction is more complex and leads generally to dehalogenation or reduction products.

The condensation of a Grignard reagents with hindered acid chlorides in THF at low temperature, yields ketones which are generally difficult to obtain and avoids the side reaction caused with a CuCl catalyst.Applied to unsaturated Grignard reagents and acid chlorides, this method also yields unsaturated ketones, such as the Artemisia ketone.

The relative selectivity of atomic halogenation of 2-substituted butanes is influenced by the phase and by solvents.There are solvents which increase the selectivity compared with the gas phase and solvents which decrease the relative selectivity.However the most striking feature of the halogenation (especially the bromination) of 2-substituted butanes is the high reactivity of the 2-position notwithstanding very unfavourable polar effects.This reactivity is attributed to the release of steric compression associated with the abstraction of the tertiary hydrogen atom.The halogenation of butan-2-ol esters is associated with some decomposition of 2-butyl radical (OCOR)CH3> and the chlorination of 2-phenylbutane with the formation of olefins 2-phenylbut -1-ene and 2-phenylbut-2-ene.

Die Regio- und Stereospezifitaeten der α-Alkinon-Cyclisierung, einer thermischen Umwandlung von Alkinyl-alkyl-ketonen, welche in β'-Stellung mindestens ein H-Atom tragen, zu 2-Cyclopentenonen wurden untersucht.Cyclisierung zum hoeher substituierten C(β')-Atom ist dabei bevorzugt, vorausgesetzt, dass die zur Insertion zur Verfuegung stehende C(β'),H-Bindung zur Propioloylseitenkette eine moeglichst synplanare Anordnung einnehmen kann.In Cyclisierungen zu β'-Methylen-C-Atomen, welche diastereotope H-Atome tragen, wird daher eines der moeglichen epimeren Produkte bevorzugt oder ausschliesslich gebildet.Die mechanistischen Konsequenzen der gefundenen Specifitaeten werden diskutiert.

The chlorination of pentanoic, 3-methylbutanoic, 2-methylbutanoic and 2,2-dimethylpropanoic acids and their derivatives with chlorine in the liquid phase have been investigated.The monochloro products formed were determined by gas-liquid chromatography (GLC) and gas-liquid chromatography-mass spectrometry (GLC-MS) as their esters through the comparison with authentic samples.The deactivation of position 2 decreases in the order COCl > CO2H > CO2CH2Cl > CO2CH3, the effect of the COCl-group in pentanoic acid derivatives being 4.3 times stronger than that of the CO2CH3-group.The deactivation is smallest in 2-methylbutanoic acid derivatives owing to the electron-donating methyl group.The EI mass spectra of the methyl and chloromethyl esters have been studied in detail.