- Preparation and root growth-modulatory activity of N-substituted 2-acetylamino-2-ethoxycarbonyl-3-(2-furyl)propanamides
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N-Substituted 2-acetylamino-2-ethoxycarbonyl-3-(2-furyl)propanamides (8) were synthesized through the reaction of amines (13) with 2-acetylamino-2-ethoxycarbonyl-3-(2-furyl)propanoic acid (3b), which was prepared via condensation of 2-(bromomethyl)furan (10b) with diethyl acetamidomalonate, followed by partial hydrolysis of the resultant diethyl ester (3a) in the presence of barium hydroxide. However, bulky amines such as tert-butyl-amine of 2-trifluoromethylaniline did not afford the corresponding diamides (8). The biological activity of the prepared diamides (8) as root growth modulators was examined by germination assay using rape and leek seeds. N-(5-Bromo-2-thiazolyl)- and N-(4-chloro-2-benzothiazolyl)-2-acetylamino-2-ethoxycarbonyl-3-(2-furyl) propanamides (8h, i) both potently inhibited the root growth of rape seedlings, but were less effective in the case of leek seeds. The herbicide 2,4-dichlorophenoxyacetic acid completely inhibited root growth in both cases.
- Kitagawa,Akiyama,Masai
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Read Online
- Design, synthesis, biological screening and molecular docking studies of novel multifunctional 1,4-di (aryl/heteroaryl) substituted piperazine derivatives as potential antitubercular and antimicrobial agents
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In this paper, two series of novel multifunctional 1, 4-di (aryl/heteroaryl) substituted piperazine derivatives (6a-d & 7a-d) were synthesized, characterized, and evaluated for their antitubercular, antibacterial, and antifungal activities. A step-wise reduction, bromination and substitution reactions on various aldehydes resulted in alcohols (2a–d), bromides (3a–d), and titled novel compounds (6a–d & 7a–d) in moderate to good yields (48–85%). The novel compounds were evaluated for their antitubercular and antimicrobial activities. Compound 7a exhibited promising antitubercular activity (MIC: 0.65 μg/mL) almost equal to the Rifampicin, while the rest of the compounds were moderately active against MTB H37Rv except 6b. Compounds 7a and 6b showed good activity against tested fungal pathogens. Compounds 7a and 7b were proven as the best bacterial agents. Molecular docking studies were in agreement with the in-vitro results. Docking analyses show that all the synthesized molecules bind to the target protein Mtb RNAP (PDB ID: 5UHC) fairly strongly. All the compounds were evaluated for their in vitro cytotoxicity effect using the MTT assay method against human cancer cell line MCF-7. The compounds demonstrated growth inhibitory effect on the cell line with significant IC50 values ranging between 8.20 and 34.45 μM. Most importantly, compound 7a displayed good binding affinity towards the tested protein with binding energy ?7.30 kcal/mol and a stronger hydrogen bond distance of 2.2 ? with ASN-493 residue. Thus, the present research highlighted the potential role of novel piperazine derivatives as potential antitubercular, and antimicrobial candidates and further good research into optimization might result in the development of new antitubercular drug candidates.
- Mekonnen Sanka, Bruktawit,Mamo Tadesse, Dereje,Teju Bedada, Endale,Mengesha, Ephriem T.,Babu G., Neelaiah
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- [1,3]-Claisen rearrangement via removable functional group mediated radical stabilization
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A thermal O-to-C [1,3]-rearrangement of α-hydroxy acid derived enol ethers was achieved under mild conditions. The 2-aminothiophenol protection of carboxylic acids facilitates formation of the [1,3] precursor and its thermal rearrangement via stabilization of a radical intermediate. Experimental and theoretical evidence for dissociative radical pair formation, its captodative stability via aminothiophenol, and a unique solvent effect are presented. The aminothiophenol was deprotected from rearrangement products as well as after derivatization to useful synthons.
- Alam, Md Nirshad,Dash, Soumya Ranjan,Mukherjee, Anirban,Pandole, Satish,Marelli, Udaya Kiran,Vanka, Kumar,Maity, Pradip
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supporting information
p. 890 - 895
(2021/02/01)
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- Aryl imidazole derivative and application thereof
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The invention relates to an aryl imidazole derivative and application thereof. The aryl imidazole derivative is a compound shown as a formula (I) in the description or pharmaceutically acceptable salt thereof. The invention also discloses application of the aryl imidazole derivative in preparation of drugs for treating cancers. The invention further discloses application of the aryl imidazole derivative in preparation of drugs for treating diseases caused by EGFR mutation.
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Paragraph 0463-0465
(2021/06/23)
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- Visible-Light-Induced Intermolecular Dearomative Cyclization of Furans: Synthesis of 1-Oxaspiro[4.4]nona-3,6-dien-2-one
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A fac-Ir(ppy)3-catalyzed intermolecular dearomative cyclization of 2-bromo-2-((5-bromofuran-2-yl)methyl)malonate and alkynes affording substituted spirolactones in yields of 19-91% via a 5-exo-dig radical cyclization under visible light is presented. This method provides a new access to the synthesis of spirocycle skeletons applying water as an external oxygen source under mild reaction conditions.
- Dong, Wuheng,Yuan, Yao,Gao, Xiaoshuang,Keranmu, Miladili,Li, Wanfang,Xie, Xiaomin,Zhang, Zhaoguo
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p. 1461 - 1467
(2019/01/21)
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- Synthesis method of furan-2-methylene boronic acid pinacol ester
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The invention relates to a synthesis method of furan-2-methylene boronic acid pinacol ester. The method is simple; the operation is easy; unstable factors unfavorable for large-scale production, suchas column chromatography are avoided; through solvent selection, the generation of byproducts can be greatly reduced; the method is applicable to large-scale production. The method comprises the synthesis steps of (1) performing bromination on furan-2-methanol; (2) coupling the furan-2-curafume and duplex boron to generate the furan-2-methylene boronic acid pinacol ester.
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Paragraph 0009
(2018/04/01)
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- Carbocation Catalyzed Bromination of Alkyl Arenes, a Chemoselective sp3 vs. sp2 C?H functionalization.
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The versatility of the trityl cation (TrBF4) as a highly efficient Lewis acid organocatalyst is demonstrated in a light induced benzylic brominaion of alkyl-arenes under mild conditions. The reaction was conducted at ambient temperature under common hood light (55 W fluorescent light) with catalyst loadings down to 2.0 mol% using N-bromosuccinimide (NBS) as the brominating agent. The protocol is applicable to an extensive number of substrates to give benzyl bromides in good to excellent yields. In contrast to most previously reported strategies, this protocol does not require any radical initiator or extensive heating. For electron-rich alkyl-arenes, the trityl ion catalyzed bromination could be easily switched between benzylic sp3 C?H functionalization and arene sp2 C?H functionalization by simply alternating the solvent. This chemoselective switch allows for high substrate control and easy preparation of benzyl bromides and bromoarenes, respectively. The chemoselective switch was also applied in a one-pot reaction of 1-methylnaphthalene for direct introduction of both sp3 C?Br and sp2 C?Br functionality. (Figure presented.).
- Ni, Shengjun,El Remaily, Mahmoud Abd El Aleem Ali Ali,Franzén, Johan
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supporting information
p. 4197 - 4204
(2018/09/25)
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- Enantioselective Total Synthesis of (+)-Wortmannin
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A concise and enantioselective total synthesis of the potent PI3K inhibitor (+)-wortmannin is described. A Pd-catalyzed cascade reaction was first developed to connect a synthon derived from Hajos-Parrish ketone to a furan moiety. The subsequent Friedel-Crafts alkylation of the β-position of a furan ring to an epoxide was optimized to establish the C10 quaternary center. (+)-Wortmannin was eventually accomplished by transformations following a late-stage oxidation of the furan allylic position. Kinome profiling and in vitro enzymatic assays were performed on 17-β-hydroxy-wortmannin and an epoxide analogue.
- Guo, Yinliang,Quan, Tianfei,Lu, Yandong,Luo, Tuoping
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supporting information
p. 6815 - 6818
(2017/05/31)
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- Novel approach towards the synthesis of poly heterocyclic compounds: Total synthesis of 12-Oxa-6,10b-epoxy-4b,5,6,10b,11,12-hexahydrochrysene
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A simple and facile synthesis of the hexahydrochrysene derivative, 12-oxa-6,10b-epoxy-4b,5,6,10b,11,12-hexahydrochrysene has been reported through the use of conventional and green methodologies. The key steps are, microwave assisted O-alkylation of a bro
- Kaur, Jasamrit
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p. 2091 - 2094
(2017/07/25)
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- An efficient and selective method for the iodination and bromination of alcohols under mild conditions
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A straightforward and effective procedure for the conversion of a variety of alcohols into the corresponding alkyl iodides and bromides is described using KX/P2O5 (X = I, Br). The reactions were easily carried out in acetonitrile under mild conditions. Using this method, the selective conversion of benzylic alcohols in the presence of aliphatic alcohols was achieved.
- Khazdooz, Leila,Zarei, Amin,Aghaei, Hamidreza,Azizi, Ghobad,Gheisari, Mohammad Mehdi
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p. 168 - 171
(2015/12/30)
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- Asymmetric Dearomatization of 1-Aminonaphthalene Derivatives through C-C Bond Formation with Electron-Rich Heterocycles as Nucleophiles
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A cationic gold(I)/axially chiral biaryl bis(phosphine) complex has been employed to catalyze the asymmetric dearomatization reactions of 1-aminonaphthalene derivatives through a C-C bond-forming reaction with electron-rich heterocycles as the nucleophiles. These reactions afford pentacyclic heterocycles in good yields with moderate enantiomeric excess (ee) values. A cationic gold(I)/axially chiral biaryl bis(phosphine) complex has been employed to catalyze the asymmetric dearomatization of 1-aminonaphthalene derivatives through a C-C bond-forming reaction with electron-rich heterocycles as the nucleophiles. These reactions afford pentacyclic heterocycles in good yields with moderate enantiomeric excess (ee) values.
- Baba, Takafumi,Oka, Junko,Noguchi, Keiichi,Tanaka, Ken
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p. 4374 - 4382
(2015/07/27)
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- Method for producing hematopoietic stem cells using pyrazole compounds
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An expanding agent for hematopoietic stem cells and/or hematopoietic progenitor cells useful as a therapy for various hematopoietic diseases and useful for improvement in the efficiency of gene transfer into hematopoietic stem cells for gene therapy is provided. A method of producing hematopoietic stem cells and/or hematopoietic progenitor cells, which comprises expanding hematopoietic stem cells by culturing hematopoietic stem cells ex vivo in the presence of a compound represented by the formula following (I), a tautomer or pharmaceutically acceptable salt of the compound or a solvate thereof (wherein R1 to R8 are as defined in the description).
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Page/Page column 184
(2016/01/10)
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- PYRAZOLE COMPOUNDS HAVING THERAPEUTIC EFFECT ON MULTIPLE MYELOMA
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Novel therapeutic agents for myeloma are provided. A therapeutic agent for multiple myeloma containing a pyrazole compound represented by the formula (1): wherein R1 is C1-C6 alkyl, C1-C6 alkyl substituted with R17, C1-C6 haloalkyl, phenyl, phenyl substituted with a R11's or the like, R2 is a hydrogen atom, C1-C6 alkyl, phenyl or phenyl optionally substituted with e R21's or the like, R3 is a hydrogen atom or the like, X is a single bond or —(CR6, R7)n—, each of R4 and R5 is independently C1-C6 alkyl or the like, R6 and R7 are hydrogen atoms or C1-C6 alkyl, R8 is phenyl, phenyl optionally substituted with k R81's or the like, a tautomer of the compound or a pharmaceutically acceptable salt or solvate thereof, as an active ingredient.
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Paragraph 0270; 0271; 0272
(2013/10/07)
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- Synthesis of benzyl bromides with hexabromoacetone: An alternative path to drug intermediates
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A series of benzyl bromides were efficiently prepared from the corresponding alcohols with Br3CCOCBr3/PPh3 at low temperatures and under neutral conditions. The present protocol was applied to the heterocyclic analogues and to the successful synthesis of the precursor of the antiulcer drug omeprazole, thus furnishing an alternate, mild method for the preparation of these drug intermediates. A significant steric factor was observed throughout both series supporting a SN2 mechanism.
- Joseph, Kara M.,Larraza-Sanchez, Isabel
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experimental part
p. 13 - 16
(2011/02/25)
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- Enantiomerically pure and highly substituted alicyclic α,α- difluoro ketones: Potential inhibitors for malarial aspartic proteases, the plasmepsins
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The design and synthesis of novel fluorinated building blocks is of major interest in the development of new pharmaceuticals and agrochemicals. A quantitative search in the Protein Data Bank (PDB) manifests the use of di- and trifluoro hydrates for bindin
- Faeh, Christoph,Mathys, Roland,Hardegger, Leo A.,Meyer, Solange,Bur, Daniel,Diederich, Francois
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supporting information; experimental part
p. 4617 - 4629
(2010/10/21)
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- ANTIVIRAL PHOSPHINATE COMPOUNDS
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The invention is related to anti-viral phosphinate compounds, compositions containing such compounds, and therapeutic methods that include the administration of such compounds, as well as to processes and intermediates useful for preparing such compounds.
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Page/Page column 196-198
(2008/06/13)
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- Integrase inhibitors
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Tricyclic compounds, protected intermediates thereof, and methods for inhibition of HIV-integrase are disclosed.
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Page/Page column 31-32
(2008/06/13)
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- Platinum-catalyzed intramolecular [4C+3C] cycloaddition between dienes and allenes
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(Chemical Equation Presented) Crossing the seven C's: The three carbon atoms of several allenyl fragments can be incorporated into seven-membered carbocycles by means of a Pt-catalyzed intramolecular [4C+3C] cycloaddition with dienes (see scheme). The tra
- Trillo, Beatriz,Lopez, Fernando,Gulias, Moises,Castedo, Luis,Mascarenas, Jose L.
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p. 951 - 954
(2008/09/20)
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- PIPERIDINONES USEFUL IN THE TREATMENT OF INFLAMMATION
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There is provided compounds of formula (I): wherein R1, R2, R3, R4, R5, R6, R7, m and n have meanings given in the description, and pharmaceutically acceptable derivatives thereof, which compounds are useful in the treatment of diseases and conditions associated with inflammation.
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Page/Page column 112
(2008/12/07)
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- COMPOUNDS AND METHODS FOR THE TREATMENT OF VIRUSES AND CANCER
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The present invention relates to compounds according to the formula I: Where Ra is H or an optionally OH-substituted C1-C3 alkyl; R1 is OR1, an optionally substituted C4-12 carbocyclic group which may be saturated or unsaturated (including aromatic) or an optionally substituted heterocyclic group; R1 is an optionally substituted C1-C14 hydrocarbyl group or an optionally substituted heterocyclic group;; R2 , R3 and R4 are each independently H, an optionally substituted C1-C4 alkyl group (preferably CH3, CH2CH3 or CF3), halogen (preferably F, Cl, Br), OR, CN, NO2, a C1-C6 thioether, a C1-C6 thioester group, an optionally substituted CO2R group, an optionally substituted COR group or an optionally substituted OCOR group (preferably R4 is H); R is H or an optionally substituted C1-C6 alkyl group; RHET is an optionally substituted heterocyclic group; and pharmaceutically acceptable salts, solvates or polymorphs thereof.
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Page/Page column 26-27
(2010/11/26)
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- Therapeutic compounds for inhibiting interleukin-12 signals and method for using same
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Novel heterocyclic compounds having a six membered ring structure fused to a five membered ring structure are found to be useful for the treatment and prevention of symptoms or manifestations associated with disorders affected by Interleukin-12 (“IL-12”) intracellular signaling, such as, for example, Th1 cell-mediated disorders. The therapeutic compounds, pharmaceutically acceptable derivatives (e.g., resolved enantiomers, diastereomers, tautomers, salts and solvates thereof) or prodrugs thereof, have the following general formula: Each X, Y and Z are independently selected from a member of the group consisting of C(R3), N, N(R3) and S. Each R1, R2 and R3 is substituted or unsubstituted and is independently selected from a member of the group consisting of hydrogen, halo, oxo, C(1-20)alkyl, C(1-20)hydroxyalkyl, C(1-20)thioalkyl, C(1-20)alkylamino, C(1-20)alkylaminoalkyl, C(1-20)aminoalkyl, C(1-20)aminoalkoxyalkenyl, C(1-20)aminoalkoxyalkynyl, C(1-20)diaminoalkyl, C(1-20)triaminoalkyl, C(1-20)tetraaminoalkyl, C(5-15)aminotrialkoxyamino, C(1-20)alkylamido, C(1-20)alkylamidoalkyl, C(1-20)amidoalkyl, C(1-20)acetamidoalkyl, C(1-20)alkenyl, C(1-20)alkynyl, C(3-8)alkoxyl, C(1-11)alkoxyalkyl, and C(1-20)dialkoxyalkyl.
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- Therapeutic compounds for inhibiting interleukin-12 signaling and methods for using same
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Novel heterocyclic compounds having a six membered ring structure fused to a five membered ring structure are found to be useful for the treatment and prevention of symptoms or manifestations associated with disorders affected by Interleukin-12 (“IL-12”) intracellular signaling, such as, for example, Th1 cell-mediated disorders. The therapeutic compounds, pharmaceutically acceptable derivatives (e.g., resolved enantiomers, diastereomers, tautomers, salts and solvates thereof) or prodrugs thereof, have the following general formula: Each X, Y and Z are independently selected from a member of the group consisting of C(R3), N, N(R3) and S. Each R1, R2 and R3 is substituted or unsubstituted and is independently selected from a member of the group consisting of hydrogen, halo, oxo, C(1-20)alkyl, C(1-20)hydroxyalkyl, C(1-20)thioalkyl, C(1-20)alkylamino, C(1-20)alkylaminoalkyl, C(1-20)aminoalkyl, C(1-20)aminoalkoxyalkenyl, C(1-20)aminoalkoxyalkynyl, C(1-20)diaminoalkyl, C(1-20)triaminoalkyl, C(1-20)tetraaminoalkyl, C(5-15)aminotrialkoxyamino, C(1-20)alkylamido, C(1-20)alkylamidoalkyl, C(1-20)amidoalkyl, C(1-20)acetamidoalkyl, C(1-20)alkenyl, C(1-20)alkynyl, C(3-8)alkoxyl, C(1-11)alkoxyalkyl, and C(1-20)dialkoxyalkyl.
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- One-pot synthesis of aryl sulfones from alcohols
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A one-pot synthesis of aryl sulfones from primary alcohols is described. Alcohols were treated with N-bromosuccinimide and triphenylphosphine, followed by addition of sodium arenesulfinate with a catalytic amount of tetrabutylammonium iodide to afford the aryl sulfones in good to high yields.
- Murakami, Teiichi,Furusawa, Kiyotaka
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p. 479 - 482
(2007/10/03)
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- THERAPEUTIC COMPOUNDS FOR INHIBITING INTERLEUKIN-12 SIGNALING AND METHODS FOR USING SAME
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Novel heterocyclic compounds having a six membered ring structure fused to a five membered ring structure are found to be useful for the treatment and prevention of symptoms or manifestations associated with disorders affected by Interleukin-12 (“IL-12”) intracellular signaling, such as, for example, Th1 cell-mediated disorders. The therapeutic compounds, pharmaceutically acceptable derivatives (e.g., resolved enantiomers, diastereomers, tautomers, salts and solvates thereof) or prodrugs thereof, have the following general formula: Each X, Y and Z are independently selected from a member of the group consisting of C(R3), N, N(R3) and S. Each R1, R2 and R3 is substituted or unsubstituted and is independently selected from a member of the group consisting of hydrogen, halo, oxo, C(1-20)alkyl, C(1-20)hydroxyalkyl, C(1-20)thioalkyl, C(1-20)alkylamino, C(1-20)alkylaminoalkyl, C(1-20)aminoalkyl, C(1-20)aminoalkoxyalkenyl, C(1-20)aminoalkoxyalkynyl, C(1-20)diaminoalkyl, C(1-20)triaminoalkyl, C(1-20)tetraaminoalkyl, C(5-15)aminotrialkoxyamino, C(1-20)alkylamido, C(1-20)alkylamidoalkyl, C(1-20)amidoalkyl, C(1-20)acetamidoalkyl, C(1-20)alkenyl, C(1-20)alkynyl, C(3-8)alkoxyl, C(1-11)alkoxyalkyl, and C(1-20)dialkoxyalkyl.
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- An Expedient Route for the Stereoselective Construction of Bridged Polyheterocyclic Ring Systems Using the Tandem "Pincer" Diels-Alder Reaction
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The tandem "pincer" Diels-Alder reaction, consisting of two consecutive [4 + 2] cycloadditions between two dienes and an acetylenic bis-dienophile, has been applied toward the rapid construction of bridged polyoxacyclic ring systems when furan derivatives are used as the diene components. The study has demonstrated the stereoselectivity (exo-exo adduct), the chemoselectivity ("pincer" vs "domino"), as well as the regioselectivity of the reaction. The reaction has been successfully applied to a variety of 2-substituted furans and tethered bis-furans in combination with mono-activated and diactivated dienophiles. The synthesis of unsymmetrical cycloadducts starting from the aza- and oxanorbornadiene-type intermediate has also been realized.
- Lautens, Mark,Fillion, Eric
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p. 4418 - 4427
(2007/10/03)
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- An improved method for the synthesis of DL-3-(2-furyl)alanine
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DL-3-(2-Furyl)alanine (1) was prepared by the condensation of 2- (bromomethyl)furan (7) with diethyl formamidomalonate (2), followed by the traditional saponification-decarboxylation techniques.
- Kitagawa, Tokujiro,Akiyama, Naohiro
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p. 1865 - 1866
(2007/10/03)
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- (Hetero)-aryl ketones derivatives with antibacterial properties
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Conformationally restricted aryl and heteroaryl ketones derived from monic acid have useful antibacterial properties.
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- Halogenation of benzyl- and (heteroaromatic methyl)cobaloximes: Direct competition between ring halogenation and cobalt-carbon bond cleavage
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(4-Acetamidobenzyl)- and (4-(dimethylamino)benzyl)cobaloximes react rapidly with low concentrations of chlorine and bromine in acetic acid or chloroform at room temperature under nitrogen. Both ring-halogenated organometallic products and direct Co-C cleavage products are formed. However, (4-methoxybenzyl)cobaloxime forms 4-methoxy-2-halotoluene as the exclusive product. (3-Methylbenzyl)cobaloxime undergoes a substantial proportion of ring substitution by both Br2 and Cl2 in competition with the cleavage of the Co-C bond. (3-Methoxybenzyl)cobaloxime forms only the ring-substituted organometallic product. A remarkable difference in reactivity between 2- and 3-isomers of the (thienylmethyl)- and (furylmethyl)cobaloximes is observed; for example, Co-C cleavage is the primary process in furfuryl- and (2-thienylmethyl)cobaloximes whereas ring halogenation occurs much faster in the 3-isomer. The results are discussed in terms of a σ-π delocalization phenomenon by which the electronic effect of a substituent in the benzyl group is effectively transmitted to the Co-C bond reactivity. The substituent effect of the metallomethyl group -CH2Co(dmgH)2py is found to be more than that of the methoxy group. The mechanism of the Co-C cleavage is described.
- Gupta,Kumar, Manoj,Roy, Sujit
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- Herbicidal 1-aryl-delta2-1,2,4-triazolin-5-ones
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Aryltriazolinones of the formula STR1 in which W is oxygen or sulfur; X1 and X2 are independently selected from halogen, haloalkyl, and alkyl; R is a three- to eight-membered ring heterocyclic group of one or two, same or different, ring heteroatoms selected from oxygen, sulfur, and nitrogen, or an alkyl radical substituted with said heterocyclic group; R1 is alkyl, haloalkyl, cyanoalkyl, alkenyl, alkynyl, or a group of the formula -alkyl-Y--R3 ; R2 is halogen, alkyl, cyanoalkyl, haloalkyl, arylalkyl, or a group of the formula -alkyl-Y--R3 ; R3 is alkyl, alkenyl, or alkynyl; and Y is oxygen or S(O)r in which r is 0 to 2 are disclosed and exemplified.
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- Intramolecular Diels-Alder Additions of Benzynes to Furans. Exploratory Studies
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A series of 3-alkoxyanthranilic acids, in which a furan ring is attached to the terminal carbon atom of the alkoxy group, has been prepared.When the chain linking the anthranilic acid and furan ring systems is three or four atoms long, decomposition of th
- Best, Wayne M.,Wege, Dieter
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p. 635 - 645
(2007/10/02)
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- Studies Dealing with the Aza-Claisen Rearrangement of 2-Allyloxy-Substituted Oxazoles
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The scope of the thermal -sigmatropic rearrangement of a number of 2-allyloxy-substituted 4,5-diphenyloxazoles has been examined.These systems undergo a facile aza-Claisen rearrangement to give 3-allyl-substituted 4,5-diphenyl-4-oxazolin-2-ones.In contrast to the thermal results, irradiation of the 2-allyloxy- or benzyloxy-substituted oxazole gave rise to a mixture of 3- and 5-substituted oxazolinones.The photolysis proceeds via C-O bond scission to generate a radical pair which subsequently recombines to produce the mixture of oxazolinones.A series of related oxazoles was prepared in which the heterocyclic ring and the ? bond are connected by an alkoxy side chain.All attempts to induce an intramolecular Diels-Alder reaction failed.The only product that could be obtained corresponds to that derived from an intramolecular ene reaction.The excited-state behavior of several 2- and 5-allyloxy-substituted oxazoles was also studied.The rationale for the difference in thermal and photochemical behavior is discussed.
- Padwa, Albert,Cohen, Leslie A.
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p. 399 - 406
(2007/10/02)
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- HALOGENATION OF THENYL AND FURYL COBALOXIMES
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The reactions of thenyl and furyl cobaloximes with halogens (bromine and chlorine) in acetic acid and chloroform indicate that, Co-C bond cleavage occurs in 2-thenyl and 2-furyl case whereas the ring substitution is faster than Co-C bond cleavage in 3-thenyl and 3-furyl cobaloximes.
- Gupta, B.D.,Roy, S.
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p. 3255 - 3256
(2007/10/02)
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- α-Amino Acids as Nucleophilic Acyl Equivalents, IV. Synthesis of Symmetrical Ketones by Means of 2-Phenyl-2-oxazolin-5-one
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2-Phenyl-2-oxazolin-5-one (2), itself easily derivable from hippuric acid (1), on reaction with allyl, benzyl or phenacyl halides undergoes 4,4-disubstitution, if the reaction is conducted in dipolar aprotic solvents in presence of weak bases.Hydrolysis of the resulting oxazolinones 3 leads to α,α-dialkylaed hippuric acids 4, which may be oxidized to symmetrical ketones 5 by means of lead tetraacetate.
- Lohmar, Rainald,Steglich, Wolfgang
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p. 3706 - 3715
(2007/10/02)
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- Bis-[5-(4-chlorophenyl)furfuryl]dialkylammonium bromides
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This invention provides a series of bis-[5-(4-chlorophenyl)furfuryl]alkylammonium bromides having utility as antibacterial agents.
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