cas 698-63-5, 5-Nitrofurfural | Articles data

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An efficient microwave-assisted method to obtain 5-nitrofurfural without solvents on mineral solid supports
5-nitrofurfural (5-NF) was quantitatively prepared by deacetylation of its geminal diacetate on K10 Montmorillonite under microwave irradiation without solvent.
Perez, Eduardo R.,Marrero, Alma L.,Perez, Rolando,Autie, Miguel A.
p. 1779 - 1782
(1995)
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Thermally Sensitive Protecting Groups for Cysteine, and Manufacture and Use Thereof
In a preferred embodiment, there is provided a protecting group for protecting the thiol side chain of a cysteine residue, the protecting group comprising a Diels-Alder cycloadduct of a furan and a maleimide, and optionally, a linker interposed between the thiol side chain and the Diels-Alder cycloadduct.
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Paragraph 0092-0093

(2021/02/12)

Industrial preparation method of nifuratel
The invention provides a preparation method of nifuratel. The preparation method comprises the following steps: (1) reacting sodium methyl mercaptide with epoxy chloropropane to prepare 2-(methylthiomethyl)-oxetane; (2) dropwise adding the 2-(methylthiomethyl)-oxygen heterocyclic propane into hydrazine hydrate, so as to prepare 3-methylthio-2-hydroxyl-propyl hydrazine; (3) adding diethyl carbonate into the 3-(methylthio-2-hydroxy)-propyl hydrazine, so as to prepare N-amino-5-(methylthiomethyl)-2-oxazolidinone; and (4) hydrolyzing the 5-nitrofuran formaldehyde diacetate in the presence of dilute acid to obtain a 5-nitrofurfural solution; under a dark condition, adding the prepared N-amino-5-methylthiomethyl-2-oxazolidinone into a 5-nitrofurfural solution, reacting at room temperature to obtain a nifuratel crude product, and recrystallizing and purifying to obtain a nifuratel pure product.
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Paragraph 0031-0084

(2021/05/05)

An aerobic oxidation of alcohols into carbonyl synthons using bipyridyl-cinchona based palladium catalyst
We have reported an aerobic oxidation of primary and secondary alcohols to respective aldehydes and ketones using a bipyridyl-cinchona alkaloid based palladium catalytic system (PdAc-5) using oxygen at moderate pressure. ThePdAc-5catalyst was analysed using SEM, EDAX, and XPS analysis. The above catalytic system is used in experiments for different oxidation systems which include different solvents, additives, and bases which are cheap, robust, non-toxic, and commercially available on the industrial bench. The obtained products are quite appreciable in both yield and selectivity (70-85%). In addition, numerous important studies, such as comparisons with various commercial catalysts, solvent systems, mixture of solvents, and catalyst mole%, were conducted usingPdAc-5. The synthetic strategy of oxidation of alcohol into carbonyl compounds was well established and all the products were analysed using1H NMR,13CNMR and GC-mass analyses.
Cheedarala, Ravi Kumar,Chidambaram, Ramasamy R.,Siva, Ayyanar,Song, Jung Il
p. 32942 - 32954
(2021/12/02)

Method for synthesizing furacilin under catalysis of supported catalyst
The invention discloses a method for synthesizing furacilin under catalysis of a supported catalyst and belongs to the field of chemical synthesis. A 5-nitrofurfural intermediate is synthesized from furfuryl alcohol used as a raw material through steps of esterification, nitration, deprotection, oxidation and the like, and then, 5-nitrofurfural and semicarbazide are subjected to a condensation reaction under the catalytic action of the supported catalyst CuO/CNTs to produce furacilin. The method is simple to operate, the adopted catalyst has the characteristics of being non-toxic, easy to remove and renewable, and the product yield is high.
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(2018/06/26)

The Hydrazine–O2 Redox Couple as a Platform for Organocatalytic Oxidation: Benzo[c]cinnoline-Catalyzed Oxidation of Alkyl Halides to Aldehydes
An organocatalytic oxidation platform that capitalizes on the capacity of hydrazines to undergo rapid autoxidation to diazenes is described. Commercially available benzo[c]cinnoline is shown to catalyze the oxidation of alkyl halides to aldehydes in a novel mechanistic paradigm involving nucleophilic attack, prototropic shift, and hydrolysis. The hydrolysis and reoxidation events occur readily with only adventitious oxygen and water. A survey of the scope of viable substrates is shown along with mechanistic and computational studies that give insight into this mode of catalysis.
Stone, Ilana B.,Jermaks, Janis,MacMillan, Samantha N.,Lambert, Tristan H.
supporting information
p. 12494 - 12498
(2018/09/18)

Method for preparing nitro compound by using graphene to catalyze carbon dioxide
The invention discloses a method for preparing a nitro compound by using graphene to catalyze carbon dioxide. A graphene material is applied to catalysis of a reaction of carbon dioxide and a nitrification substrate such as an aromatic compound to prepare the nitro compound. The method is used for replacing a traditional nitric acid/sulfur acid method to prepare the nitro compound, so that the atom utilization rate of the reaction is increased, the energy is saved, and the emission is reduced; and the method has the characteristic of atom economy during industrial preparation of the nitro compound.
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Paragraph 0037-0038

(2018/06/16)

Synthesis, characterization and antiinflammatory activity of chalcone derivatives linked with apocynin and 5-nitrofuran moiety
The present paper describes the synthesis of some new chalcone derivatives i.e. 1-[3-methoxy-4-(5-nitro-furan-2-ylmethoxy)-phenyl]-3-(substituted phenyl)-propenone derivatives (9A-9K) from furfural and apocynin as starting materials. Claisen-Schmidt reaction of 1-(4-((5-nitrofuran-2-yl)methoxy)-3-methoxyphenyl)ethanone (7) with aromatic aldehydes (8A-K) under solvent free conditions using solid NaOH as catalyst at room temperature resulted in the formation of chalcone derivatives (9A-9K) in 86-96 % yield. These compounds were characterized by 1H NMR, Mass and IR spectroscopy and were evaluated for their anti-inflammatory activity.
Kumar Reddy,Kathale, Niren E.
p. 312 - 316
(2018/01/11)

Preparation and Characterization of a Small Library of Thermally-Labile End-Caps for Variable-Temperature Triggering of Self-Immolative Polymers
The reaction between furans and maleimides has increasingly become a method of interest as its reversibility makes it a useful tool for applications ranging from self-healing materials, to self-immolative polymers, to hydrogels for cell culture and for the preparation of bone repair. However, most of these applications have relied on simple monosubstituted furans and simple maleimides and have not extensively evaluated the potential thermal variability inherent in the process that is achievable through simple substrate modification. A small library of cycloadducts suitable for the above applications was prepared, and the temperature dependence of the retro-Diels-Alder processes was determined through in situ 1H NMR analyses complemented by computational calculations. The practical range of the reported systems ranges from 40 to >110 °C. The cycloreversion reactions are more complex than would be expected based on simple trends expected based on frontier molecular orbital analyses of the materials.
Taimoory, S. Maryamdokht,Sadraei, S. Iraj,Fayoumi, Rose Anne,Nasri, Sarah,Revington, Matthew,Trant, John F.
supporting information
p. 4427 - 4440
(2018/04/26)

Preparation process of anti-infective drug nifuratel
The invention belongs to the technical field of drug synthesis and in particular relates to a preparation process of an anti-infective drug nifuratel. The preparation process comprises the following steps: taking iodomethane, sodium sulfide and chlorocyclopropane as initial raw materials to obtain epoxy propyl methyl sulfide, carrying out ring-opening reaction with hydrazine hydrate to obtain 3-methylmercapto-2-hydroxyl-propylhydrazine, carrying out a ring-closure reaction to obtain N-amino-5-methylthiomethyl-2-oxazolidinone, hydrolyzing 5-nitro furfural diacetate in the presence of trifluoroacetic acid to obtain 5-nitro-2-furancarboxaldehyde, and performing condensation with N-amino-5-methylthiomethyl-2-oxazolidinone, thereby obtaining the nifuratel. Safe and cheap reagents are selected in the process route, and environment hazards are reduced. Meanwhile, the operating difficulty and reaction after-treatment burdens are reduced, the production safety is ensured, the process is a simple, green and economic process route for preparing the nifuratel, and the obtained product is high in yield, excellent in purity and suitable for large-scale industrial production of the nifuratel.
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Paragraph 0024; 0066-0071

(2018/05/16)

Nifuratel preparation method
The invention belongs to the technical field of synthesis of medicines and particularly relates to a nifuratel preparation method. The nifuratel preparation method comprises the following steps: taking epoxy propyl dimethyl sulfide as the starting material, having a ring-opening reaction with tert-butyl carbazate to obtain N'-(2-hydroxyl-3-methylmercapto-propyl)-tert-butyl carbazate; having a ringclosing reaction with urea under the catalytic action of cuprous bromide, obtaining a key intermediate N-(Boc-amino)-5-methylmercapto-methyl-2-oxazolidinone; hydrolyzing 5-nitro furfural diacetate under the action of trifluoroacetic acid to obtain 5-nitrofurfural, condensing with N-(Boc-amino)-5-methylmercapto-methyl-2-oxazolidinone, and obtaining nifuratel. In the process route, the cheap easy-to-get agents are chose, the operation difficulty and the processing burden caused after the reaction are reduced, the environmental harm is reduced, the production safety is guaranteed, and the preparation method is an easy, green and economical process route for the preparation of the nifuratel.
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Paragraph 0068; 0069; 0070; 0073

(2018/08/04)

Process for removing nifuratel cyclization impurities
The invention relates to nifuratel, in particular to a process for removing nifuratel cyclization impurities. The process for removing the nifuratel cyclization impurities comprises the step of preparing a hydrazinolysis product, namely 3-methyl thio-2-hydroxyl-propyl hydrazine and is characterized in that the 3-methyl thio-2-hydroxyl-propyl hydrazine, diethyl carbonate and sodium methoxide are mixed, then cyclized and filtered to obtain cyclization mother liquor, and the cyclization mother liquor is subjected to adsorption treatment through a macro-porous resin packing column, then is condensed with 5-nitro furfural and is re-crystallized to obtain nifuratel. The process provided by the invention has the beneficial effects that through performing treatment on the cyclization mother liquorthrough the macro-porous resin packing column, a cyclized product is completely separated from cyclized impurities and other impurities. The invention overcomes the defect that an existing process cannot completely remove the cyclized impurities and the other impurities and finds a simple, effective, safe and environment-friendly method suitable for industrialization.
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Paragraph 0032; 0035; 0037; 0042; 0047

(2018/09/11)

Dehydrogenation of 5-hydroxymethylfurfural to diformylfuran in compressed carbon dioxide: An oxidant free approach
The dehydrogenation of biomass-based 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) was achieved utilizing an activated carbon supported rhodium (Rh/C) catalyst under mild reaction conditions. The developed method successfully afforded complete conversion and the highest selectivity of DFF (>99%) without any additive, conventional hydrogen acceptor and oxidant. The efficiency of the method is achieved by the addition of compressed carbon dioxide (scCO2) and the synergistic effect of scCO2 and Rh/C, where scCO2 plays a pivotal role in accelerating the reaction by removing hydrogen, and consequently shifting the equilibrium to the forward direction. Optimization of different reaction parameters ensures the achievement of high conversion and selectivity. Characterization of the catalyst using different spectroscopic techniques suggests an interaction between the substrate and the catalyst and provides an indication of the possible reaction pathway, thus a mechanism would be outlined. The rate determining step of the reaction was calculated through mechanistic investigations involving theoretical calculations together with experimental analysis. One of the most attractive features of the method developed in this study is the reverse reaction of DFF, which can be achieved in one-pot without the addition of any external hydrogen. This process has successful application to the dehydrogenation of a variety of alcohols with different substituents.
Chatterjee, Maya,Ishizaka, Takayuki,Chatterjee, Abhijit,Kawanami, Hajime
p. 1315 - 1326
(2017/08/15)

NOVEL COMPOUND, ORGANIC CATION TRANSPORTER 3 DETECTION AGENT, AND ORGANIC CATION TRANSPORTER 3 ACTIVITY INHIBITOR
[Problem] The present invention addresses the problem of providing a novel compound. The present invention also addresses the problem of providing an OCT3 detection agent or an OCT3 activity inhibitor, which comprises the novel compound. [Solution] A compound represented by formula (A), a pharmaceutically acceptable salt thereof, or a pharmaceutically acceptable solvate thereof. ????????R1-R2-R3-R4?????(A)
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Paragraph 0874-0876

(2016/08/17)

Development of Glucose Regulated Protein 94-Selective Inhibitors Based on the BnIm and Radamide Scaffold
Glucose regulated protein 94 (Grp94) is the endoplasmic reticulum resident of the heat shock protein 90 kDa (Hsp90) family of molecular chaperones. Grp94 associates with many proteins involved in cell adhesion and signaling, including integrins, Toll-like receptors, immunoglobulins, and mutant myocilin. Grp94 has been implicated as a target for several therapeutic areas including glaucoma, cancer metastasis, and multiple myeloma. While 85% identical to other Hsp90 isoforms, the N-terminal ATP-binding site of Grp94 possesses a unique hydrophobic pocket that was used to design isoform-selective inhibitors. Incorporation of a cis-amide bioisostere into the radamide scaffold led to development of the original Grp94-selective inhibitor, BnIm. Structure-activity relationship studies have now been performed on the aryl side chain of BnIm, which resulted in improved analogues that exhibit better potency and selectivity for Grp94. These analogues also manifest superior antimigratory activity in a metastasis model as well as enhanced mutant myocilin degradation in a glaucoma model compared to BnIm.
Crowley, Vincent M.,Khandelwal, Anuj,Mishra, Sanket,Stothert, Andrew R.,Huard, Dustin J. E.,Zhao, Jinbo,Muth, Aaron,Duerfeldt, Adam S.,Kizziah, James L.,Lieberman, Raquel L.,Dickey, Chad A.,Blagg, Brian S. J.
p. 3471 - 3488
(2016/05/19)

Method for preparing 5-nitro-2-furaldehyde and nifuratel
The invention discloses a method for preparing 5-nitro-2-furaldehyde. The method comprises the following steps: a) 5-nitryl furfural ester diacetate, low alcohol, inorganic acid, lewis acid or a mixture of the above components are subjected to a reaction for 1-2 hours at the temperature of 70-90 DEG C to obtain a reaction solution containing 5-nitro-2-furaldehyde; b) removing low alcohol from the reaction solution in the step a) through vacuum concentration to obtain a concentrate; dissolving the concentrate by dichloromethane, washing the concentrate, drying the concentrate, performing vacuum concentration to obtain a crude product; and c) purifying the crude product in the step b) through silica-gel column chromatography to obtain 5-nitro-2-furaldehyde. The method has the advantages of less side reaction and short reaction time, and can increase the yield and purity of the 5-nitro-2-furaldehyde. The prepared 5-nitro-2-furaldehyde has the advantages that impurity is little, purifying treatment is not required, the 5-nitro-2-furaldehyde can be directly used for preparing nifuratel, preparation operation steps of nifuratel are simplified, and the yield and the purity of nifuratel are increased.
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Paragraph 0075-0081

(2017/04/25)

Nifuratel method for the preparation of
The invention relates to a method for preparing nifuratel. The method comprises the steps of (1) synthesizing 2-(methylmercapto-methyl)-oxacyclopropane through epoxy chloropropane and sodium methyl mercaptide; (2) generating reaction between hydrazine hydrate and the 2-(methylmercapto-methyl)-oxacyclopropane to synthesize 3-methylmercapto-2-hydroxy-propyl hydrazine; (3) generating reaction between diethyl carbonate and 3-methylmercapto-2-hydroxy-propyl hydrazine to prepare N-amino-5-methylmercapto-methyl-2-oxazolidinone; (4) hydrolyzing 5-nitrofuran formaldehyde diacetate ester under an acidic condition to prepare 5-nitro-2-furaldehyde; (5) generating reaction between the 5-nitro-2-furaldehyde and the N-amino-5-methylmercapto-methyl-2-oxazolidinone obtained in the step (3) to obtain the nifuratel, wherein in the step (1), 15-crown ether-5 is used as a catalyst, so that the conversion rate is high; no organic solvent is used during posttreatment of a product, and the posttreatment is simple.
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Paragraph 0049

(2016/12/01)

As shown in a formula E micromolecule method for the preparation of the compounds of
The invention discloses a preparation method of a compound nifuratel as shown in the formula E. purity of the compound nifuratel product as shown in the formula E reaches more than 99.97%; postprocessing yield reaches more than 96%; and total yield reaches more than 104%. The preparation method is simple and easy to control. Postprocessing operation is convenient and easy to implement. The preparation method is more beneficial to large-scale industrial production and application. Raw materials used in the invention are greatly supplied at home and are cheap in price. Thus, environmental pollution is further minimized.
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Paragraph 0067; 0071; 0072; 0073

(2016/12/01)

A method for synthesizing micromolecule
The invention discloses a synthetic method of nifuratel. The synthetic method comprises the steps of carrying out a substitution reaction between epoxy chloropropane and sodium methyl mercaptide in the presence of a phase transfer catalyst to obtain epoxy propyl dimethyl sulfide, and then performing hydrazinolysis, cyclization and condensation on the obtained epoxy propyl dimethyl sulfide to obtain the nifuratel. The synthetic method is high in nifuratel yield, high in purity and low in impurity content; besides the method has the advantages that a ring-closure reaction is carried out under the alkaline condition of sodium methoxide, the use of metal sodium is avoided, production safety is ensured, and simultaneously, the reaction is easy to arouse, easy to control in process, the used raw materials are easy to get, basically no waste liquid is generated in the reaction of each step, and therefore, industrial pollution is greatly reduced; and as a result, the synthetic method of nifuratel is applicable to industrial production.
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Paragraph 0047

(2016/12/01)

Silver(I)-Promoted ipso-Nitration of Carboxylic Acids by Nitronium Tetrafluoroborate
A novel and efficient method for the regioselective nitration of a series of aliphatic and aromatic carboxylic acids to their corresponding nitro compounds using nitronium tetrafluoroborate and silver carbonate in dimethylacetamide has been described. This transformation is believed to proceed via the alkyl-silver or aryl-silver intermediate, which subsequently reacts with the nitronium ion to form nitro substances. Mild reaction conditions, tolerant of a broad range of functional groups, and formation of only the ipso-nitrated products are the key features of this methodology when compared to known methods for syntheses of nitroalkyls and nitroarenes.
Natarajan, Palani,Chaudhary, Renu,Venugopalan, Paloth
p. 10498 - 10504
(2015/11/18)

IBX works efficiently under solvent free conditions in ball milling
IBX (2-iodoxybenzoic acid), discovered in 1893, is an oxidant in synthetic chemistry whose extensive use is impeded by its explosiveness at high temperature and poor solubility in common organic solvents except DMSO. Since the discovery of Dess-Martin Periodinane in 1983, several modified IBX systems have been reported. However, under ball milling conditions, IBX works efficiently with various organic functionalities at ambient temperature under solvent free conditions. Also, the waste IBA (2-iodosobenzoic acid) produced from the reactions was in situ oxidized to IBX in the following step using oxone and thus reused for multiple cycles by conserving its efficiency (only ～6% loss after 15 cycles). This work describes an overview of a highly economical synthetic methodology which overcomes the problems of using IBX, efficiently in gram scale and in a non-explosive way. This journal is the Partner Organisations 2014.
Achar, Tapas Kumar,Maiti, Saikat,Mal, Prasenjit
p. 12834 - 12839
(2014/04/03)

Simple preparation and application of TEMPO-coated Fe3O 4 superparamagnetic nanoparticles for selective oxidation of alcohols
The organic oxidant TEMPO (2,2,4,4-tetramethylpiperdine-1-oxyl) was immobilized on iron oxide (Fe3O4) superparamagnetic nanoparticles by employing strong metal-oxide chelating phosphonates and azide/alkyne "click" chemistry. This simple preparation yields recyclable TEMPO-coated nanoparticles with good TEMPO loadings. They have excellent magnetic response and efficiently catalyze the oxidation of a wide range of primary and secondary alcohols to aldehydes, ketones, and lactones under either aerobic acidic MnII/CuII oxidizing Minisci conditions, or basic NaOCl Anelli conditions. The nanoparticles could be recycled more than 20 times under the Minisci conditions and up to eight times under the Anelli conditions with good to excellent substrate conversions and product selectivities. Immobilization of the catalyst through a phosphonate linkage allows the particles to withstand acidic oxidizing environments with minimal catalyst leaching. Clicking TEMPO to the phosphonate prior to phosphonate immobilization, rather than after, ensures the clicked catalyst is the only species on the particle surface. This facilitates quantification of the catalyst loading. The stability of the phosphonate linker and simplicity of this catalyst immobilization method make this an attractive approach for tethering catalysts to oxide supports, creating magnetically separable catalysts that can be used under neutral or acidic conditions. Recycling to a different TEMPO: An extremely simple and economic synthesis of a recyclable 2,2,4,4-tetramethylpiperdine-1-oxyl(TEMPO)-coated superparamagnetic catalyst is described. The catalyst shows excellent performance in the rapid oxidation of primary and secondary benzylic and aliphatic alcohols by using oxygen and MnII/CuII or biphasic NaOCl/KBr conditions.
Tucker-Schwartz, Alexander K.,Garrell, Robin L.
experimental part
p. 12718 - 12726
(2011/02/21)

Sulphated zirconia as an eco-friendly catalyst in acylal preparation under solvent-free conditions, acylal deprotection assisted by microwaves, and the synthesis of anhydro-dimers of o-hydroxybenzaldehydes
A solvent-free approach is described for the regioselective synthesis of acylals (1,1-diacetates) in shorter reaction times and higher yields, compared to conventional methodology using solvents. In the protection reaction of the o-hydroxybenzaldehyde the formation of acetyl compounds and anhydro-dimers was observed. The deprotection reaction involves microwave (MW) exposure of diluted reactants in the presence of solid sulphated zirconia (SZ) catalyst that can be easily recovered and reused. The sulphated zirconia was recycled several times without any loss of activity.
Palacios-Grijalva, Laura Nadxieli,Cruz-Gonzalez, Deysi Y.,Lomas-Romero, Leticia,Gonzalez-Zamora, Eduardo,Ulibarri, Gerardo,Negron-Silva, Guillermo E.
experimental part
p. 4065 - 4078
(2010/03/01)

Synthesis, antitubercular and anticancer activities of substituted furyl-quinazolin-3(4H)-ones
Some novel substituted-3-{[(1E)-(substituted-2-furyl)-methylene]amino} quinazolin-4(3H)-one (5, 6, 7) a-f were synthesized by a multi-step process. These synthesized compounds are characterized by various spectroscopic techniques and evaluated for their antitubercular and anticancer activities. Biological activity indicated that some of the title compounds are potent antitubercular and anticancer agents.
Raghavendra, Nulgulmnalli M.,Thampi, Parameshwaran,Gurubasavarajaswamy, Purvarga M.,Sriram, Dharmarajan
p. 635 - 641
(2008/12/21)

CARBO- AND HETERO-CYCLIC ANTIBIOTICS AND USE THEREOF
The present invention relates to compounds of the formula (1.0); and pharmaceutically acceptable salts of such compounds. The present invention relates to chemical entities containing a nitrofuran or other antibiotic linked to an activity enhancing distal ring system either directly or via an imine group, vinyl group, carbo- or hetero-cyclic chain or ring or a combination of an imine group or a vinyl group and a carbo- or hetero-cyclic chain or ring. Antibiotic activity is obtained, for example, by the nitrofuran moiety, while the remaining structure of the molecule contributes to additional antimicrobial activity and/or extends the antimicrobial spectrum of activity, by facilitating nitroreduction by microorganisms, uptake in target bacteria, and/or intracellular penetration, while also contributing to pharmacological properties (absorption, body distribution, and others).
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Page/Page column 27

(2008/06/13)

COMBRETASTATIN DERIVATIVES WITH CYTOTOXIC ACTION
The invention described herein relates to new combretastatin derivatives obtained by total synthesis and having the following general formula (I) in which the groups are as defined in the description here below. Said compounds, though chemically related to the structure of cis/trans-combretastatin, do not always bind tubulin, but nevertheless exhibit cytotoxic activity of interest in the oncological field as anticancer and/or antiangiogenic agents.
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Page 32

(2010/02/10)

HALOGENATED QUINAZOLINYL NITROFURANS AS ANTIBACTERIAL AGENTS
The present invention includes novel compounds of the formula (I) wherein X is absent or trans or cis CHCH, R1 is (C1-C10) alkyl unsubstituted or substituted by one to three hydroxy, (C1-C10) alkenyl unsubstituted or substituted by one to three hydroxy, (C1-C10) alkynyl unsubstituted or substituted by one to three hydroxy, or aryl unsubstituted or substituted by one to three hydroxy; R2 is hydrogen, alkyl or aryl; R3 and R4 are, independently of each other, H, halogen, or a solubilizing group, with the proviso that at least one of R3 and R4 is halogen; and pharmaceutically acceptable salts thereof. The invention also includes pharmaceutically acceptable formulations of said compounds which exhibit antibiotic activity against a wide spectrum of microorganisms including organisms which are resistant to multiple antibiotic families and are useful as antibacterial agents for treatment or prophylaxis of bacterial infections, or their use as antiseptics, agents for sterilization or disinfection.
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Page/Page column 18

(2008/06/13)

Caro's acid supported on silica gel. Part VI. A mild reagent for regeneration of carbonyl compounds from acetals, ketals, and 1,1-diacetates
Efficient conversion of acetals, ketals, and diacetates to carbonyl compounds is described using Caro's acid supported on silica gel. The deacetalization reactions are carried out in acetonitrile at room temperature. Reaction of diacetates is performed in refluxing dichloromethane, and their parent carbonyl compounds are obtained in good-to-excellent yields.
Lakouraj,Tajbakhsh,Khojasteh,Gholami
p. 2645 - 2651
(2007/10/03)

Spontaneous dehydration mechanism of aromatic aldehyde reactions with hydroxyl and non-hydroxyl amines
The plot of rate constants vs. pH for the dehydration step of the reaction between furfural and 5-nitrofurfural with hydroxylamine, N-methylhydroxylamine, and O-methylhydroxylamine, shows two regions corresponding to the oxonium ion-catalyzed and spontaneous dehydration. The oxonium ion-catalyzed dehydration region of the reaction of furfural with the above mentioned hydroxylamines exhibits general acid catalysis with excellent Bronsted correlation (Bronsted coefficients: 0.76 (r = 0.986), 0.68 (r = 0.987), and 0.67 (r = 0.993) respectively). However, the rate constants of the spontaneous dehydration of these hydroxylamines, where water is considered the general acid catalyst, exhibit a large positive deviation from the Bronsted line. This fact was not observed in the reaction of non-hydroxyl amines with different aromatic aldehydes by other authors, thus supporting that the spontaneous dehydration steps for these reactions proceed by intramolecular catalysis. The mechanism of intramolecular catalysis might be stepwise. First, a zwitterionic intermediate is formed. It can then evolve in the second step by loss of water, or follow a concerted pathway, with the transference of a proton through a five-membered ring (general intramolecular acid catalysis). In the case of non-hydroxyl amines, data suggested the possibility of a mechanism of intramolecular proton transfer through one or two water molecules, from the nitrogen of the amine to the leaving hydroxide ion.
Travalon, Silvana Azzolini,Brighente, Ines Maria Costa,Yunes, Rosendo Augusto
p. 685 - 692
(2007/10/03)

Isoquinoline compound melanocortin receptor ligands and methods of using same
The invention relates to melanocortin receptor ligands and methods of using the ligands to alter or regulate the activity of a melanocortin receptor. The invention further relates to tetrahydroisoquinoline aromatic amines that function as melanocortin receptor ligands and as agents for controlling cytokine-regulated physiologic processes and pathologies, and combinatorial libraries thereof.
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(2008/06/13)

Syntheses and spectral properties of unsymmetrically 3,5-disubstituted 2,6-dimethyl-1,4-dihydropyridines
Unsymmetrically 3,5-disubstituted 4-(5-X-2-furyl)-2,6-dimethyl-1,4-dihydropyridines (where X = H, Br, NO2) have been synthesized and characterized by spectral methods (IR, UV, 1H NMR and MS). The modified Hantzsch method made it possible to prepare the title compounds as well as their N-alkylated derivatives. The paper also describes the N-alkylation of sodium salts of substituted 1,4-dihydropyridines using the phase-transfer catalysis.
Ilavsky, Dusan,Milata, Viktor
p. 1233 - 1243
(2007/10/03)

Action of boron trifluoride etherate and stannic chloride on heterocyclic aromatic acetals
Twelve heterocyclic aromatic acetals (1a-12a) have been synthesised and their reactions with Lewis acids, viz. boron trifluoride etherate (BTE) and stannic chloride (STC) have been studied.The acetals yield ethers, esters and aldehydes with BTE, but only esters and aldehydes with STC.Interestingly, pyridine-2-aldehyde acetal (12a), yields aldehyde alone, that too in low yield.Probable mechanisms have been suggested for the product formation.
Raja, S.,Xavier, N.,Arulraj, S. J.
p. 687 - 689
(2007/10/02)

Modified Procedure for the Preparation of 5-Nitro-2-furylmethylene Diacetate and Its Use in the Synthesis of Some Novel (5-Nitro-2-furyl)azomethines via 5-Nitro-2-furaldehyde
A modified two-step procedure for the preparation of 5-nitro-2-furylmethylene diacetate (3) by nitration of 2-furaldehyde (1) or 2-furylmethylene diacetate (4) with acetyl nitrate via 2-acetoxy-5-nitro-2,5-dihydro-2-furylmethylene diacetate (2), or 1,1,5-triacetoxy-2-hydroxy-5-nitro-3-penten (5) and 1,1,5-triacetoxy-2-hydroxy-5-nitro-2,4-pentadiene (6), has been developed.Acid hydrolysis of 3 yields 5-nitro-2-furaldehyde (7) which is used in the carbonylamine condensation with various hydrazines (9-11, 14, 17, 19, 21, 24, 25, 28, 29, 32, 34, 36, 38, 39, 41 and 44-54) prepared by known methods, in order to obtain some novel potentially pharmaceutically active (5-nitro-2-furyl)azomethines.
Vlaovic, Djordje,Milic, Bozidar Lj.,Mackenzie, Kenneth
p. 1201 - 1218
(2007/10/02)

CALCIUM ANTAGONIST N-HETERO ESTER 1,4-DIHYDROPYRIDINES
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(2008/06/13)

Radical-Nucleophillic Substitution (SRN1) Reactions. Part 3. Reactions of α-Substituted 2-Methyl-5-nitrofurans with the Anion of 2-Nitropropane
The anion of 2-nitropropane reacts with α-substituted 2-methyl-5-nitrofurans by a SRN1 mechanism (via carbon) and/or by a SN2 mechanism (via oxygen).
Beadle, Charles D.,Bowman, W. Russell
p. 1814 - 1823
(2007/10/02)

ESR SPECTRA OF ELECTROCHEMICALLY GENERATED ANION RADICALS OF THE NITROFURAN SERIES
ESR spectra of anion radicals for 29 derivatives of 5-nitrofuran, elctrochemically generated in situ, have been obtained and studied.Using spectral HFS constants and quantum chemical model parameters (INDO), the structures of ?- and ?-electron systems of 2-nitrofuran and its anion radical have been investigated.Furan ring substituent effects on lone electron distribution have been investigated.On the lone electron level, transmission of substituent effects through the ring has been found to be higher in the case of furan, and lower in the case of thiophene and selenophene, with respect to the benzene ring.Delocalization of the lone electron in various ring-attached substituents has been elucidated.Kinetic studies of radical decay showed a rise in stability with increasing delocalization of the lone electron.
Gavars, R.,Stradins, J.,Baumane, L.,Baider, L.
p. 183 - 198
(2007/10/02)

Synthesis of Some Transition Metal Chelates of Furfurylidene and 5-Nitrofurfurylidene Benzoyl Hydrazones as Potential Fungicides
Twelve complexes of the general formulae ML2 and M'L2*2H2O, where M = Ni(II), Cu(II) and Zn(II) and M' = Mn(II), Fe(II) and Co(II) and L = Furfurylidene benzoyl hydrazone (FBHZ) or 5-Nitrofurfurylidene benzoylhydrazone (5-NFBHZ), have been synthesised and characterised.The Schiff bases coordinate through O, N atoms behaving as monobasic bidentate ligands, depending on the pH of the medium.These complexes have exhibited significant fungitoxicity against Rhixoctonia solani, the causative organism of sheath blight in rice and groundnut plants.Some of the chelates exhibited more toxicity when compared to Dithane, M-45, a commercial fungicide, screened in similar conditions.The fungitoxicity of the metal chelates was found to be in the following order Cu > Ni > Fe > Zn > Mn > Co.
Rao, Surya D.,Ganorkar, M. C.
p. 217 - 219
(2007/10/02)

The Reaction of Aniline with 5-Nitro-2-furaldehyde. A Model for Non-Enzymic Browning Reactions
The condensation between 5-nitro-2-furaldehyde and aniline, a model for food browning reactions, yields the corresponding Schiff base, 5-nitro-2-furfurylideneaniline, cleanly.The corresponding reaction with 2-furaldehyde itself yields, in contrast, a mixture of products.Since the equilibrium constant for formation of the Schiff base from 5-nitro-2-furaldehyde and aniline, 177 dm3mol-1, is not large enough to drive the reaction to completion at moderate concentrations of aniline, phenylhydrazine was employed to trap the Schiff base as it was formed: that is, the reaction with aniline was studied by examining aniline-catalysed phenylhydrazone formation.
Rio, Maria D. del,Ojeda, Olga D. de,Urquia, M.,Scarabino, Carlos,Yunes, Rosendo A.
p. 519 - 525
(2007/10/02)

THE CONVERSION OF 5-NITROFURFURYL DERIVATIVES INTO 5-AMINOFURFURYLIDENEMALONODINITRILE
The reaction of 5-nitrofurfuryl bromide or 5-nitrofurfuryl iodide with sodium azide and malonodinitrile afforded 5-aminofurfurylidenemalonodinitrile.The intermediate of the reaction is 5-nitrofurfuryl azide which decomposes to give 5-nitrofurfurylideneamine.Its reaction with malonodinitrile gives 5-nitrofurfurylidenemalonodinitrile which react further with sodium azide and malonodinitrile to give 5-aminofurfurylidenemalonodinitrile.
Povazanec, Frantisek,Kovac, Jaroslav,Hesek, Dusan
p. 752 - 754
(2007/10/02)

βLactam antibiotics and process for their use
6-[α-(Imidazolidin-2-on-1-ylcarbonylamino)-substutited acetamido]penicillanic acids, and the correspondingly 7-substituted ceph-3-em-4-carboxylic acids, characterized by the presence of a methyleneamino or substituted methyleneamino group on the 3-nitrogen atom of the imidazolidine ring are antibacterial agents. The compounds, of which 6-[α-(3-benzaliminoimidazolidin-2-on-1-ylcarbonylamino)cyclohexa-1,4-dien-1-ylacetamido]penicillanic acid and 7-[α-(3-furylideneaminoimidazolidin-2-on-1-ylcarbonylamino)phenylacetamido]-3-(3-methylthiadiazol-5-ylthiomethyl)ceph-3-em-4-carboxylic acid are typical examples, are prepared through acylation of an 6-[α-(amino)substituted acetamido]penicillanic acid or the corresponding 7-[α-(amino)substituted acetamido]ceph-3-em-4-carboxylic acid with a reactive nucleofugic derivative of a 3-methyleneaminoimidazolidin-2-on-1-carboxylic acid.
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(2008/06/13)

Synthesis and quantitative structure-activity relationships of antibacterial 1-(substituted benzhydryl)-4-(5-nitro-2- furfurylideneamino)piperazines
1-Benzhydryl-4-(5-nitro-2-furfurylideneamino)piperazine and 11 substituted analogs were prepared and examined for in vitro antimicrobial activity. The compounds were active against Bacillus cereus 7, Bacillus megaterium 122, Bacillus subtilis 104, Clostridium perfringens 13, and the tetracycline-resistant Clostridium perfringens 37. Regression analyses on the antibacterial activity data based on the Hansch approach, using π, π2, and σ parameters, yielded several statistically significant correlation equations. 1-Benzhydryl-4-(5-nitro-2-furfurylideneamino)piperazine stopped the protein and DNA syntheses in C. perfringens 13, as indicated by precipitable radioactivity. The compound, however, showed no effect on the cell wall synthesis in the bacteria.
Yung,Gilroy,Mahony
p. 900 - 905
(2007/10/04)

2-[2-(5-Nitro-2-furyl)vinyl]-4-(anilino)quinazolines
2-[2-(5-Nitro-2-furyl)vinyl]-4-(anilino)quinazolines and 2-[2-(5-nitro-2-furyl)vinyl]-4-(hydroxyanilino)quinazolines are prepared and used as pesticides and animal growth promotants. These quinazolines also improve the feed efficiency of animals.
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(2008/06/13)