- Synthesis and evaluation of the antimalarial, anticancer, and caspase 3 activities of tetraoxane dimers
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The synthesis of a range of mono spiro and dispiro 1,2,4,5-tetraoxane dimers is described. Selected molecules were examined in in vitro assays to determine their antimalarial and anticancer potential. Our studies reveal that several molecules possess potent nanomolar antimalarial and single digit micromolar antiproliferative IC50s versus colon (HT29-AK and leukemia (HL60) cell lines.
- Amewu, Richard K.,Chadwick, James,Hussain, Afthab,Panda, Somnath,Rinki, Rinki,Janneh, Omar,Ward, Stephen A.,Miguel, Candel,Burrell-Saward, Hollie,Vivas, Livia,O'Neill, Paul M.
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- Synthesis and antileishmanial activity of 1,2,4,5-tetraoxanes against leishmania donovani
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A chemically diverse range of novel tetraoxanes was synthesized and evaluated in vitro against intramacrophage amastigote forms of Leishmania donovani. All 15 tested tetraoxanes displayed activity, with IC50 values ranging from 2 to 45 μm. The most active tetraoxane, compound LC140, exhibited an IC50 value of 2.52 ± 0.65 μm on L. donovani intramacrophage amastigotes, with a selectivity index of 13.5. This compound reduced the liver parasite burden of L. donovani-infected mice by 37% after an intraperitoneal treatment at 10 mg/kg/day for five consecutive days, whereas miltefosine, an antileishmanial drug in use, reduced it by 66%. These results provide a relevant basis for the development of further tetraoxanes as effective, safe, and cheap drugs against leishmaniasis.
- Cabral, Lília I.L.,Pomel, Sébastien,Cojean, Sandrine,Amado, Patrícia S.M.,Loiseau, Philippe M.,Cristiano, Maria L.S.
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- A new method for the synthesis of bishydroperoxides based on a reaction of ketals with hydrogen peroxide catalyzed by boron trifluoride complexes
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A reaction of cycloalkanone, alkanone and alkyl aryl ketone ketals with H2O2 catalyzed by boron trifluoride etherate and boron trifluoride-methanol complexes was studied. A new versatile method for the synthesis of bishydroperoxides and their derivatives, viz. 1,1′ -dihydroperoxyperoxides and 1,2,4,5-tetraoxacyclohexanes, was developed based on this reaction.
- Terent'ev, Alexander O.,Kutkin, Alexander V.,Platonov, Maxim M.,Ogibin, Yuri N.,Nikishin, Gennady I.
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Read Online
- Synthesis of Non-symmetrical Dispiro-1,2,4,5-Tetraoxanes and Dispiro-1,2,4-Trioxanes Catalyzed by Silica Sulfuric Acid
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A novel protocol for the preparation of non-symmetrical 1,2,4,5-tetraoxanes and 1,2,4-trioxanes, promoted by the heterogeneous silica sulfuric acid (SSA) catalyst, is reported. Different ketones react under mild conditions with gem-dihydroperoxides or peroxysilyl alcohols/β-hydroperoxy alcohols to generate the corresponding endoperoxides in good yields. Our mechanistic proposal, assisted by molecular orbital calculations, at the ωB97XD/def2-TZVPP/PCM(DCM)//B3LYP/6-31G(d) level of theory, enhances the role of SSA in the cyclocondensation step. This novel procedure differs from previously reported methods by using readily available and inexpensive reagents, with recyclable properties, thereby establishing a valid alternative approach for the synthesis of new biologically active endoperoxides.
- Amado, Patrícia S. M.,Coelho, Jaime A. S.,Cristiano, Maria L. S.,Frija, Luís M. T.,O'neill, Paul M.
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p. 10608 - 10620
(2021/07/31)
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- Synthesis, Antimalarial Activity Evaluation and Molecular Docking Studies of Some New Substituted Spiro-1,2,4,5-Tetraoxane Derivatives
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Eight new substituted spiro-1,2,4,5-tetraoxane derivatives were synthesized and characterized by a number of analytical and spectroscopic techniques. The molecules were subsequently screened for in vitro antimalarial activity against chloroquine sensitive (3D7) and chloroquine resistant (RKL-9) strains of Plasmodium falciparum. These substituted spiro-1,2,4,5-tetraoxane derivatives were studied by molecular docking analysis in the active site of Falcipain-2 as a putative protein. Most of the synthesized compounds exhibited moderate to very good activity toward the parasite in comparison to the standard drug, chloroquine. Three compounds showed potent antimalarial activity against chloroquine sensitive strain of P. falciparum (3D7). One compound 5b (3-ethyl-3-methyl-1,2,4,5-tetraoxa-spiro[5.5]undecane) showed a very good activity against both chloroquine sensitive strain (3D7) with MIC = 1.95 ± 0.06 μg/mL and IC50 = 1.95 ± 0.06 μg/mL compared to chloroquine (MIC = 0.4 ± 0.10 μg/mL, IC50 = 0.04 ± 0.01 μg/mL) as well as chloroquine-resistant strain of P. falciparum (RKL-9) with MIC = 15.63 ± 0.70 μg/mL and IC50 = 3.90 ± 0.09 μg/mL compared to chloroquine (MIC = 25.00 ± 0.20 μg/mL, IC50 = 0.39 ± 0.02 μg/mL). The top scored compounds having low binding energy interact with the active site of Falcipain-2 in molecular docking studies.
- Chetia, Dipak,Kumawat, Mukesh Kumar
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p. 814 - 820
(2021/11/26)
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- Tetroxanes as New Agents against Leishmania amazonensis
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Leishmaniasis is a neglected disease, caused by a parasite of Leishmania genus and widespread in the tropical and subtropical areas of the world. Currents drugs are limited due to their toxicity and parasite resistance. Therefore, the discovery of new treatment, more effective and less toxic, is urgent. In this study, we report the synthesis of six gem-dihydroperoxides (2a–2f), with yields ranging from 10 % to 90 %, utilizing a new methodology. The dihydroperoxides were converted into ten tetroxanes (3a–3j), among which six (3b, 3c, 3d, 3g, 3h and 3j) showed activity against intracellular amastigotes of Leishmania amazonensis. The cytotoxicity of all compounds was also evaluated against canine macrophages (DH82), human hepatoma (HepG2) and monkey renal cells (BGM). Most compounds were more active and less toxic than potassium antimonyl tartrate trihydrate, used as positive control. Amongst all tetroxanes, 3b (IC50=0.64 μm) was the most active, being more selective than positive control in relation to DH82, HepG2 and BGM cells. In summary, the results revealed a hit compound for the development of new drugs to treat leishmaniasis.
- Almeida, Raquel M.,Antolínez, Isabel V.,Baldaia, Almodvar,Barbosa, Luiz C. A.,Borgati, Tatiane F.,Ferreira, Sebasti?o R.,Fujiwara, Ricardo T.
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- Perhydrolysis in Ethereal H2O2 Mediated by MoO2(acac)2: Distinct Chemoselectivity between Ketones, Ketals, and Epoxides
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Ketones, ketals, and epoxides were converted into corresponding hydroperoxides in high yields by reaction with ethereal H2O2 in the presence of a catalytic amount of MoO2(acac)2 with distinct (to date unattainable) chemoselectivity.
- An, Xiaosheng,Zha, Qinghong,Wu, Yikang
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supporting information
p. 1542 - 1546
(2019/02/26)
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- Di(hydroperoxy)alkane Adducts of Phosphine Oxides: Safe, Solid, Stoichiometric, and Soluble Oxidizing Agents
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The di(hydroperoxy)alkane adducts of phosphine oxides 1–9, Ph3PO?(HOO)2CMe2, Cy3PO?(HOO)2CMe2, Ph3PO? (HOO)2CMeEt, Cy3PO?(HOO)2CMeEt, Cy3PO?(HOO)2CEt2, Cy3PO? (HOO)2C(CH2)5, Cy3PO?(HOO)2CMePh, (Ph2P(O)CH2CH2P(O)Ph2)? ((HOO)2CEt2)2, and Ph2P(O)CH2P(O)Ph2?(HOO)2CMe2, respectively, are synthesized and fully characterized by 1H, 13C, and 31P NMR, and IR spectroscopies. Single crystal X-ray structures are reported for 3–9. Different one-pot synthetic pathways, starting from R3P, R3PO, R3PO?H2O, and R3PO?H2O2 are explored and discussed and a mechanism for the formation of the di(hydroperoxy)alkane adducts of phosphine oxides is suggested. The longevity of the adducts is tested by monitoring the oxidation of Ph3P with quantitative NMR. The solubilities of the adducts in organic solvents are presented, and their applicability as stoichiometric oxidizing agents for the selective oxidation of sulfides to sulfoxides is reported.
- Ahn, Shin Hye,Bhuvanesh, Nattamai,Blümel, Janet
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p. 16998 - 17009
(2017/10/12)
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- Heteropoly acid/NaY zeolite as a reusable solid catalyst for highly efficient synthesis of gem-dihydroperoxides and 1,2,4,5-Tetraoxanes
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Gem-Dihydroperoxides and 1,2,4,5-Tetraoxanes were synthesised from aldehydes and ketones catalysed by heteropoly acid/NaY zeolite (HPA/NaY) as a new, effective and reusable solid catalyst using 30% aqueous hydrogen peroxide at room temperature. The reactions proceeded with high rates and excellent yields.
- Khosravi, Kaveh,Zendehdel, Mojgan,Naserifar, Shirin,Tavakoli, Fatemeh,Khalaji, Kobra,Asgari, Atefeh
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p. 744 - 749
(2016/12/30)
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- Synthesis, antimalarial activity evaluation and docking studies of some novel tetraoxaquines
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Tetraoxaquines, molecular hybrids of 1,2,4,5-tetraoxane and 4-aminoquinoline, were designed via molecular docking analysis against Falcipain-2. Among the studied compounds, 11 top scoring analogues showing low binding energy were further selected for synthesis and evaluated for their in vitro antimalarial activity. In inhibitory assay, five compounds showed significant activity against chloroquine-resistant strain of P. falciparum-RKL-9 with IC50 values of 3.906, 3.942, 4.272, 3.906, 4.814 μg/ml.
- Kumawat, Mukesh Kumar,Parida, Pratap,Chetia, Dipak
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p. 1993 - 2004
(2016/10/03)
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- Catalyst-free and selective oxidation of pyridine derivatives and tertiary amines to corresponding N-oxides with 1,2-diphenyl-1,1,2,2-tetrahydroperoxyethane
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The catalyst-free oxidation of various pyridine derivatives and tertiary amines to their corresponding N-oxides with 1,1,2,2-tetrahydroperoxy-1,2-diphenylethane as an efficient oxidant has been developed. The methodology proved to tolerate a number of functional groups. The reactions proceeded smoothly under solvent-free and mild conditions at room temperature. All the products were easily extracted from the reaction mixtures in excellent yields. Graphical abstract: The catalyst-free oxidation of various pyridine derivatives and tertiary amines to their corresponding N-oxides with 1,1,2,2-tetrahydroperoxy-1,2-diphenylethane as an efficient oxidant has been developed. The methodology proved to tolerate a number of functional groups. The reactions proceeded smoothly under solvent-free and mild conditions at room temperature. All the products were easily extracted from the reaction mixtures in excellent yields.
- Azarifar, Davood,Mahmoudi, Boshra
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p. 645 - 651
(2016/02/19)
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- Sulfamic acid: as a green and reusable homogeneous catalyst for peroxidation of ketones and aldehydes using aqueous 30 % H2O2
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Abstract Sulfamic acid has been used as an active, low-cost and reusable solid catalyst for conversion of ketones and aldehydes to corresponding gem-dihydroperoxides using 30 % aqueous hydrogen peroxide at room temperature. The reactions proceed with high rates and excellent yields.
- Khosravi, Kaveh,Pirbodaghi, Fariba,Kazemi, Samira,Asgari, Atefe
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p. 1333 - 1337
(2015/06/22)
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- Tetraoxanes as inhibitors of apicomplexan parasites Plasmodium falciparum and Toxoplasma gondii growth and anti-cancer molecules
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New cyclohexylidene 1,2,4,5-tetraoxanes with polar guanidine and urea based groups were synthesized and evaluated for their antimalarial activity against chloroquine resistant and susceptible Plasmodium falciparum strains. The derivatives showed moderate, nM range antimalarial activities and low cytotoxicity. The N-phenylurea derivative 24 exhibited the best resistance indices (RIW2 = 0.44, RITM91C235 = 0.80) and was not toxic against human normal peripheral blood mononuclear cells (IC50 > 200 μM). Seven derivatives were tested in vitro against four human cancer cell lines and they demonstrated high selectivity toward leukaemia K562 cells. One compound, derivative 21 with a primary amino group, was the first tetraoxane tested in vivo against Toxoplasma gondii as another apicomplexan parasite. Subcutaneous administration at a dose of 10 mg kg-1 day-1 for 8 days allowed the survival of 20 % of infected mice, thus demonstrating the high potential of tetraoxanes for the treatment of apicomplexan parasites.
- Opsenica, Dejan M.,Radivojevic, Jelena,Matic, Ivana Z.,?tajner, Tijana,Kne?evic-U?aj, Slavica,Djurkovic-Djakovic, Olgica,?olaja, Bogdan A.
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p. 1339 - 1359
(2016/02/18)
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- Poly(N-vinylpyrrolidone)-H2O2 and poly(4-vinylpyridine)-H2O2 complexes: Solid H 2O2 equivalents for selective oxidation of sulfides to sulfoxides and ketones to gem-dihydroperoxides
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Complexes of poly(N-vinylpyrrolidone) (PVD) and poly(4-vinylpyridine) (PVP) with hydrogen peroxide have been prepared and their synthetic utility as solid H2O2 equivalents for the selective oxidation of sulfides to sulfoxides and ketones to gem-dihydroperoxides has been studied. These complexes are convenient and safe alternatives to H2O2 solutions and it is found that various symmetric as well as unsymmetrical sulfides undergo oxidation under mild conditions to provide the respective sulfoxides in high yields. A series of gem-dihydroperoxides were obtained from the corresponding ketones in good yields under ambient conditions. This journal is the Partner Organisations 2014.
- Surya Prakash,Shakhmin, Anton,Glinton, Kevin E.,Rao, Sneha,Mathew, Thomas,Olah, George A.
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supporting information
p. 3616 - 3622
(2014/07/08)
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- Synthesis of gem-dihydroperoxides from ketones and aldehydes using silica sulfuric acid as heterogeneous reusable catalyst
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Silica sulfuric acid (SSA) was found to efficiently catalyze the conversion of aldehydes and ketones directly into the corresponding gem-dihydroperoxides (DHPs) on treatment with aqueous 30% H2O2 at room temperature. Mild reaction conditions, good to excellent yields, short reaction times, low environmental impact, and recyclability of the catalyst are the main advantages of this synthetic method.
- Azarifar, Davood,Najminejad, Zohreh,Khosravi, Kaveh
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p. 826 - 836
(2013/02/23)
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- Triflic acid-functionalized silica-coated magnetic nanoparticles as a magnetically separable catalyst for synthesis of gem-dihydroperoxides
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Triflic acid-functionalized silica-coated magnetic nanoparticles [γ-Fe2O3@SiO2-TfOH] were readily prepared and identified as an effictive catalyst for the transformation of aldehydes or ketones into their corresponding gem-dihydroperoxides with 30% aqueous hydrogen peroxide. The catalyst was easily separated by magnetic decantation and the recovered catalyst was reused for seven cycles without significant loss of catalytic activity. Copyright
- Liu, Yong-Hui,Deng, Jia,Gao, Jian-Wu,Zhang, Zhan-Hui
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experimental part
p. 441 - 447
(2012/04/04)
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- Zinc chloride anhydrous as new and effective catalyst for conversion of ketones and aldehydes to corresponding gem-dihydroperoxides
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Zinc chloride anhydrous has been used as an efficient and new catalyst for conversion of ketones and aldehydes to corresponding gem-dihydroperoxides by aqueous hydrogen peroxide (30%) in room temperature with excellent yields and notable reaction times.
- Khosravia, Kaveh,Kazemib, Samira
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experimental part
p. 641 - 644
(2012/09/07)
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- A facile and efficient Bi(III) catalyzed synthesis of 1,1-dihydroperoxides and 1,2,4,5-tetraoxanes
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Bismuth triflate is a remarkably efficient and mild catalyst for the synthesis of both 1,1-dihydroperoxides and 1,2,4,5-tetraoxanes. The successful application of this methodology for the synthesis of both symmetrical and unsymmetrical tetraoxanes is demonstrated.
- Sashidhara, Koneni V.,Avula, Srinivasa Rao,Ravithej Singh,Palnati, Gopala Reddy
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supporting information; experimental part
p. 4880 - 4884
(2012/09/07)
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- Unique trifurcated hydrogen bonding in a pseudopolymorph of tricyclohexane triperoxide (TCTP) and its thermal studies
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Tricyclohexane triperoxide (TCTP) was synthesized as a main by-product of tetraoxane synthesis and was characterized by spectroscopic techniques viz. 1H NMR, 13C NMR, FT-IR and Raman. The single crystal X-ray structure revealed the inclusion of solvent in 1:1 stoichiometric ratio involving a unique trifurcated C(sp3)-H...O hydrogen bonding imparting remarkable symmetry to the molecule. The thermal stability of single crystal was determined by TG-DTA and DSC.
- Neupane, Chiranjeev Sharma,Awasthi, Satish Kumar
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supporting information
p. 6067 - 6070,4
(2020/08/20)
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- AlCl3.6H2O as a catalyst for simple and efficient synthesis of gem-dihydroperoxides from ketones and aldehydes using aqueous H2O2
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AlCl3.6H2O was explored as an efficient catalyst for the synthesis of gem-dihydroperoxides (DHPs) from ketones and aldehydes. The reactions took place within a short period of time using (30%) aqueous H 2O2 as a "green" oxidant in acetonitrile under neutral conditions at room temperature to afford the products in high yields.
- Azarifar,Khosravi
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experimental part
p. 1006 - 1013
(2012/02/04)
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- Efficient synthesis of gem-dihydroperoxides with molecular oxygen and anthraquinone under visible light irradiation with fluorescent lamp
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We developed an efficient dihydroperoxidation protocol of various carbonyl compounds with molecular oxygen and anthraquinone in 2-propanol under visible light irradiation with a fluorescent lamp, which produced corresponding gem-dihydroperoxides in high yields.
- Cui, Lei,Tada, Norihiro,Okubo, Hiroaki,Miura, Tsuyoshi,Itoh, Akichika
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supporting information; experimental part
p. 2347 - 2350
(2011/10/12)
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- Phosphomolybdic acid catalyzed synthesis of 1,2,4,5-tetraoxanes
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1,1-Dihydroperoxides were converted into 1,2,4,5-tetraoxanes through condensation with the corresponding ketones in 36-91% yields using phosphomolybdic acid as the catalyst and anhydrous MgSO4 as the water scavenger. Georg Thieme Verlag Stuttgart · New York.
- Yan, Xing,Chen, Jinglei,Zhu, Yun-Ting,Qiao, Chunhua
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body text
p. 2827 - 2830
(2012/01/03)
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- Mild and efficient strontium chloride hexahydrate-catalyzed conversion of ketones and aldehydes into corresponding gem-dihydroperoxides by aqueous H 2O2
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SrCl2·6H2O has been shown to act as an efficient catalyst for the conversion of aldehydes or ketones into the corresponding gem-dihydroperoxides (DHPs) by treatment with aqueous H 2O2 (30%) in acetonitrile. The reactions proceed under mild and neutral conditions at room temperature to afford good to excellent yields of product.
- Azarifar, Davood,Khosravi, Kaveh,Soleimanei, Fatemeh
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experimental part
p. 1433 - 1441
(2010/09/04)
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- A facile catalyst-free synthesis of gem-dihydroperoxides with aqueous hydrogen peroxide
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gem-Dihydroperoxides were easily obtained from the corresponding carbonyl compounds in high yields through a catalyst-free method with aqueous H 2O2 (35%) in 1,2-dimethoxyethane at room temperature.
- Tada, Norihiro,Cui, Lei,Okubo, Hiroaki,Miura, Tsuyoshi,Itoh, Akichika
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supporting information; experimental part
p. 1772 - 1774
(2010/07/04)
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- An efficient synthesis of gem-dihydroperoxides with molecular oxygen and anthracene under light irradiation
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A new efficient dihydroperoxidation protocol of a wide variety of carbonyl compounds with molecular oxygen, anthracene, and 2-propanol under light irradiation afforded their corresponding gem-dihydroperoxides in high yields.
- Tada, Norihiro,Cui, Lei,Okubo, Hiroaki,Miura, Tsuyoshi,Itoh, Akichika
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supporting information; scheme or table
p. 2383 - 2386
(2010/12/25)
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- Reaction of enol ethers with the I2-H2O2 system: Synthesis of 2-iodo-1-methoxy hydroperoxides and their deperoxidation and demethoxylation to 2-iodo ketones
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The reaction of enol ethers with the I2-H2O 2 system in diethyl ether affords 2-iodo ketones and the previously unknown 2-iodo-1-methoxy hydroperoxides. In the presence of the I 2-H2O2 system, the latter compounds undergo deperoxidation and demethoxylation to form 2-iodo ketones. The reaction conditions were found for the synthesis of 2-iodo ketones from enol ethers in 67-94% yields. Georg Thieme Verlag Stuttgart - New York.
- Terent'ev, Alexander O.,Borisov, Alexander M.,Platonov, Maxim M.,Starikova, Zoya A.,Chernyshev, Vladimir V.,Nikishin, Gennady I.
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experimental part
p. 4159 - 4166
(2011/03/18)
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- A broadly applicable mild method for the synthesis of gem-diperoxides from corresponding Ketones or 1,3-dioxolanes
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Ketones or ketals were readily converted into the corresponding gem-dihydroperoxides in high yields by treatment with ethereal H 2O2 at ambient temperature in the presence of 2-5 mol % of phosphomolybdic acid.
- Li, Yun,Hao,Zhang, Qi,Wu, Yikang
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supporting information; experimental part
p. 1615 - 1618
(2009/08/07)
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- PROCESS FOR THE PREPARATION OF FIPRONIL AND ANALOGUES THEREOF
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The present invention relates to a new and efficient process for preparing 5-amino-1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-4-(trifluoromethylthio)-IH-pyrazole-3-carbonitrile (hereinafter referred to as compound of formula I), which is useful as an intermediate for the antiparasitic agent fipronil, and a process for preparing 5-amino-3-cyano-l-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethyl sulfinylpyrazole (hereinafter referred to as compound of formula II or fipronil). In one aspect, there is provided a process for preparing fipronil comprising: a) a step of reacting CF3S(=O)ONa with the compound of formula (III) in the presence of a reducing/halogenating agent; and b) a step of oxidizing the compound of formula (I) obtained in step a) in the presence of a selective oxidizing agent, under suitable conditions, wherein the selective oxidizing agent selectively effects oxidation of (I) to the corresponding sulfoxide, Fipronil. In certain exemplary embodiments, the selective oxidizing agent is MHSO5, wherein M is an alkaline metal cation.
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(2009/07/18)
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- Stannous chloride dihydrate: A novel and efficient catalyst for the synthesis of gem-dihydroperoxides from ketones and aldehydes
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Ketones and aldehydes undergo facile hydroperoxidation on treatment with aqueous hydrogen peroxide (30%) in the presence of 10 mol% stannous chloride dihydrate in acetonitrile under very mild conditions to afford the corresponding gem-dihydroperoxides in satisfactory yields. Georg Thieme Verlag Stuttgart.
- Azarifar, Davood,Khosravi, Kaveh,Soleimanei, Fatemeh
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experimental part
p. 2553 - 2556
(2009/12/25)
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- A novel rapid sulfoxidation of sulfides with cyclohexylidenebishydroperoxide
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Cyclohexylidenebishydroperoxide was successfully used as the oxygen source for the oxidation of sulfides to sulfoxides for the first time. The sulfoxides were obtained in good to high yields without any detectable over-oxidation to sulfones under normal conditions.
- Jon Paul Selvam,Suresh,Rajesh,Chanti Babu,Suryakiran,Venkateswarlu
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p. 3463 - 3465
(2008/09/21)
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- Oxidation of cycloalkanones with hydrogen peroxide: an alternative route to the Baeyer-Villiger reaction. Synthesis of dicarboxylic acid esters
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The acid-catalyzed oxidation of cycloalkanones C5-C8 and C12 with hydrogen peroxide in alcohols was performed, and dicarboxylic acid esters were obtained as the major products in 53-70% yields. In the first step, geminal bishydroperoxides are generated from five-to-seven-membered cyclic ketones. The Baeyer-Villiger reaction is a side process accompanied by the formation of ω-hydroxycarboxylic acid esters.
- Terent'ev, Alexander O.,Platonov, Maxim M.,Kashin, Alexey S.,Nikishin, Gennady I.
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p. 7944 - 7948
(2008/12/21)
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- Mild and efficient Re(VII)-catalyzed synthesis of 1,1-dihydroperoxides
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(Chemical Equation Presented) Re2O7 in CH 3CN is a remarkably efficient and mild catalyst for the peroxyacetalization of ketones, aldehydes, or acetals by H2O 2 to generate 1,1-dihydroperoxides. Me3SiOReO3 and methyl rhenium trioxide (MTO) are also effective catalysts under these reaction conditions.
- Ghorai, Prasanta,Dussault, Patrick H.
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supporting information; experimental part
p. 4577 - 4579
(2009/05/11)
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- DISPIRO TETRAOXANE COMPOUNDS
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A compound having the formula (I) wherein ring A represents a substituted or unsubstituted monocyclic or multicyclic ring; m=any positive integer; n=0-5; X=CH and Y=-C(O)NR1R2, -NR1R2 or -S(O)2R4, where R1, R2 and R4 are each individually selected from the group consisting of H, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted amine, substituted or unsubstituted carbocyclic ring, substituted or unsubstituted heterocyclic ring, or any combination thereof, or R1 and R2 are linked so as to form part of a substituted or unsubstituted heterocyclic ring, or X=N and Y=-S(O)2R3 or -C(O)R3, where R3 is selected from the group consisting of H, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted amine, substituted or unsubstituted carbocyclic ring, substituted or unsubstituted heterocyclic ring or any combination thereof.
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Page/Page column 48
(2008/06/13)
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- Chemical stability of the peroxide bond enables diversified synthesis of potent tetraoxane antimalarials
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Of 17 prepared 1,2,4,5-tetraoxacyclohexanes stable to reductive and acidic conditions, 3 of them were more active than artemisinin against CQ and MFQ resistant strain TM91C235 and all compounds were more active in vitro against W2 than against D6 strain. In vivo, amines 10 and 11a cured all mice at higher doses with MCD ≤ 37.5 (mg/kg)/day. Triol 13 was exceptionally active against melanoma (LOX IMVI) and ovarian cancer (IGROV1), both with LC50 = 60 nM.
- Opsenica, Igor,Opsenica, Dejan,Smith, Kirsten S.,Milhous, Wilbur K.,?olaja, Bogdan A.
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p. 2261 - 2266
(2008/12/20)
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- Synthesis of cyclic peroxides containing the Si-gem-bisperoxide fragment. 1,2,4,5,7,8-hexaoxa-3-silonanes as a new class of peroxides
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(Chemical Equation Presented) A method was developed for the synthesis of the previously unknown class of organic peroxides, 1,2,4,5,7,8-hexaoxa-3- silonanes, based on the reaction of dialkyldichlorosilanes with 1,1′-dihydroperoxyperoxides. 1,2,4,5,7,8-Hexaoxa-3-silonanes are rather stable under ambient conditions and were characterized by NMR spectroscopy, X-ray diffraction, and elemental analysis. Their yields are in a range of 59-96%. The attempts were made to prepare 1,2,4,5-tetraoxa-3-silinanes by the reaction of dialkyldichlorosilanes with gem-bishydroperoxides. 1,2,4,5-Tetraoxa-3-silinanes were detected by NMR spectroscopy; these compounds rapidly decompose upon isolation.
- Terent'ev, Alexander O.,Platonov, Maxim M.,Tursina, Anna I.,Chernyshev, Vladimir V.,Nikishin, Gennady I.
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p. 3169 - 3174
(2008/09/19)
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- Synthesis of spiro-1,2-dioxolanes and their activity against Plasmodium falciparum
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Artemisinin-derived compounds play an integral role in current malaria chemotherapy. Given the virtual certainty of emerging resistance, we have investigated spiro-1,2-dioxolanes as an alternative scaffold. The endoperoxide functionality was generated by the SnCl4-mediated annulation of a bis-silylperoxide and an alkene. The first set of eight analogs gave EC50 values of 50-150 nM against Plasmodium falciparum 3D7 and Dd2 strains, except for the carboxylic acid analog. A second series, synthesized by coupling a spiro-1,2-dioxolane carboxylic acid to four separate amines, afforded the most potent compound (EC50 ~5 nM).
- Martyn, Derek C.,Ramirez, Armando P.,Beattie, Meaghan J.,Cortese, Joseph F.,Patel, Vishal,Rush, Margaret A.,Woerpel,Clardy, Jon
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scheme or table
p. 6521 - 6524
(2009/10/02)
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- Facile epoxidation of α,β-unsaturated ketones with cyclohexylidenebishydroperoxide
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Cyclohexylidenebishydroperoxide was successfully used as the oxygen source for the oxidation of α,β-unsaturated ketones for the first time. The corresponding epoxides were obtained in excellent yields under the Weitz-Scheffer reaction conditions.
- Jakka, Kavitha,Liu, Jinyun,Zhao, Cong-Gui
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p. 1395 - 1398
(2007/10/03)
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- A simple and efficient synthesis of gem-dihydroperoxides from ketones using aqueous hydrogen peroxide and catalytic ceric ammonium nitrate
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Ketones were efficiently converted into the corresponding gem-dihydroperoxides in high yields within a short period of time on treatment with aqueous H2O2 (50%) in the presence of a catalytic amount of CAN in acetonitrile at room temperature.
- Das, Biswanath,Krishnaiah, Maddeboina,Veeranjaneyulu, Boyapati,Ravikanth, Bommena
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p. 6286 - 6289
(2008/02/10)
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- Convenient synthesis of geminal bishydroperoxides by the reaction of ketones with hydrogen peroxide
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A convenient procedure was developed for the synthesis of geminal bishydroperoxides by the sulfuric acid-catalyzed reaction of ketones with hydrogen peroxide in THF. Gem-bishydroperoxides were prepared by the reactions of five- to seven-membered cycloalkanones without additional purification in 80-95% yields with a purity of more than 95%; their acyclic analogs were prepared in 43-72% yields. Copyright Taylor & Francis Group, LLC.
- Terent'ev,Platonov,Ogibin,Nikishin
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p. 1281 - 1287
(2008/02/01)
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- Spiro- and dispiro-1,2-dioxolanes: Contribution of iron(II)-mediated one-electron vs two-electron reduction to the activity of antimalarial peroxides
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Fourteen spiro- and dispiro-1,2-dioxolanes were synthesized by peroxycarbenium ion annulations with alkenes in yields ranging from 30% to 94%. Peroxycarbenium ion precursors included triethylsilyldiperoxyketals and -acetals derived from geminal dihydroperoxides and from a new method employing triethylsilylperoxyketals and -acetals derived from ozonolysis of alkenes. The 1,2-dioxolanes were either inactive or orders of magnitude less potent than the corresponding 1,2,4-trioxolanes or artemisinin against P. falciparum in vitro and P. berghei in vivo. In reactions with iron(II), the predominant reaction course for 1,2-dioxolane 3a was two-electron reduction. In contrast, the corresponding 1,2,4-trioxolane 1 and the 1,2,4-trioxane artemisinin undergo primarily one-electron iron(II)-mediated reductions. The key structural element in the latter peroxides appears to be an oxygen atom attached to one or both of the peroxide-bearing carbon atoms that permits rapid β-scission reactions (or H shifts) to form primary or secondary carbon-centered radicals rather than further reduction of the initially formed Fe(III) complexed oxy radicals.
- Wang, Xiaofang,Dong, Yuxiang,Wittlin, Sergio,Creek, Darren,Chollet, Jacques,Charman, Susan A.,Tomas, Josefina Santo,Scheurer, Christian,Snyder, Christopher,Vennerstrom, Jonathan L.
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p. 5840 - 5847
(2008/03/17)
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- Design and synthesis of orally active dispiro 1,2,4,5-tetraoxanes; Synthetic antimalarials with superior activity to artemisinin
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The design and synthesis of dispiro- and spirotetraoxanes through acid-catalyzed cyclocondensation of bis(hydroperoxides) with ketones were investigated. Various modular synthetic methods were used to enable many different analogues to be prepared from common achiral synthetic intermediates and some of the key reactions employed include reductive amination and mixed anhydride amide coupling reactions. The synthesis of 1,2,4,5-tetraoxanes was also dependent on several factors, including the structure of the ketone or aldehyde, temperature, solvent, pH, and the equilibria between the ketone and the precursors of cyclic peroxides. The required 1,2,4,5-tetraoxane was formed by crosscondensation of the bis(hydroperoxide) and the 1,4-cyclohexanedione was obtained in low temperature. Reductive amination of the ketone with various amino compounds also produced compounds in moderate to good quantities.
- Amewu, Richard,Stachulski, Andrew V.,Ward, Stephen A.,Berry, Neil G.,Bray, Patrick G.,Davies, Jill,Labat, Gael,Vivas, Livia,O'Neill, Paul M.
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p. 4431 - 4436
(2008/09/19)
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- A New Method for the Synthesis of gem-Dihydroperoxides
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The tungstic acid-catalysed reaction of ketals with hydrogen peroxide provides a convenient and efficient method for preparing gem-dihydroperoxides.
- Jefford, Charles W.,Li, Yun,Jaber, Amer,Boukouvalas, John
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p. 2589 - 2596
(2007/10/02)
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