24759-97-5Relevant articles and documents
Synthesis of Non-symmetrical Dispiro-1,2,4,5-Tetraoxanes and Dispiro-1,2,4-Trioxanes Catalyzed by Silica Sulfuric Acid
Amado, Patrícia S. M.,Coelho, Jaime A. S.,Cristiano, Maria L. S.,Frija, Luís M. T.,O'neill, Paul M.
, p. 10608 - 10620 (2021/07/31)
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.
Exploring a pocket for polycycloaliphatic groups in the CXCR3 receptor with the aid of a modular synthetic strategy
Wijtmans, Maikel,Verzijl, Dennis,van Dam, Cindy M.E.,Bosch, Leontien,Smit, Martine J.,Leurs, Rob,de Esch, Iwan J.P.
supporting information; scheme or table, p. 2252 - 2257 (2009/12/03)
A CXCR3 pocket capable of accommodating polycycloaliphatics was explored using a modular synthetic strategy. The systematic studies reveal that the tricyclic 2-adamantane and bicyclic (iso)bornyl group are efficiently recognized by CXCR3.
Two-step synthesis of achiral dispiro-1,2,4,5-tetraoxanes with outstanding antimalarial activity, low toxicity, and high-stability profiles
Ellis, Gemma L.,Amewu, Richard,Sabbani, Sunil,Stocks, Paul A.,Shone, Alison,Stanford, Deborah,Gibbons, Peter,Davies, Jill,Vivas, Livia,Charnaud, Sarah,Bongard, Emily,Hall, Charlotte,Rimmer, Karen,Lozanom, Sonia,Jesús, María,Gargallo, Domingo,Ward, Stephen A.,O'Neill, Paul M.
, p. 2170 - 2177 (2008/12/21)
A rapid, two-step synthesis of a range of dispiro-1,2,4,5-tetraoxanes with potent antimalarial activity both in vitro and in vivo has been achieved. These 1,2,4,5-tetraoxanes have been proven to be superior to 1,2,4-trioxolanes in terms of stability and to be superior to trioxane analogues in terms of both stability and activity. Selected analogues have in vitro nanomolar antimalarial activity and good oral activity and are nontoxic in screens for both cytotoxicity and genotoxicity. The synthesis of a fluorescent 7-nitrobenza-2-oxa-1,3-diazole (NBD) tagged tetraoxane probe and use of laser scanning confocal microscopy techniques have shown that tagged molecules accumulate selectively only in parasite infected erythrocytes and that intraparasitic formation of adducts could be inhibited by co-incubation with the iron chelator desferrioxamine (DFO).
Piperidine dispiro-1,2,4-trioxane analogues
Sabbani, Sunil,Stocks, Paul A.,Ellis, Gemma L.,Davies, Jill,Hedenstrom, Erik,Ward, Stephen A.,O'Neill, Paul M.
scheme or table, p. 5804 - 5808 (2009/06/30)
Dispiro N-Boc-protected 1,2,4-trioxane 2 was synthesised via Mo(acac)2 catalysed perhydrolysis of N-Boc spirooxirane followed by condensation of the resulting β-hydroperoxy alcohol 10 with 2-adamantanone. N-Boc 1,2,4-trioxane 2 was converted to the amine 1,2,4-trioxane hydrochloride salt 3 which was subsequently used to prepare derivatives (4-7). Several of these novel 1,2,4-trioxanes had nanomolar antimalarial activity versus the 3D7 strain of Plasmodium falciparum. Amine intermediate 3 represents a versatile derivative for the preparation of achiral arrays of trioxane analogues with antimalarial activity.
Sulfur ylides in reactions with 5-X-adamantan-2-ones. Stereochemistry and reactivity
Catanoso, Giada,Di Credico, Barbara,Vecchi, Elisabetta
, p. 2151 - 2160 (2007/10/03)
This work describes the stereochemistry and the relative rates of epoxidation reactions of the title compounds with sulfur ylides (methylenedimethylsulfurane and methylenedimethyloxysulfurane) in DMSO and C6H6. The electronic perturbative effect of substituent X depends on the solvent and on the reactant. It is transmitted in opposite way in solvents of different polarity depending on the reactant. The electronegativity of the substituent scarcely affects the percentages of axial/equatorial attack. The percentage of equatorial attack with methylenedimethyloxysulfurane is markedly lower for 5-X-adamantan-2-ones than for 4-X-cyclohexanones.
Substituted perhydrofuropyrans: Easy preparation from 2-chloromethyl-3- (2-methoxyethoxy)propene through 3-methylene-1,6-diols
Lorenzo, Emilio,Alonso, Francisco,Yus, Miguel
, p. 1661 - 1665 (2007/10/03)
The reaction of 2-chloromethyl-3-(2-methoxyethoxy)prop-1-ene (1) with an excess of lithium powder and a catalytic amount of naphthalene (2.5%) in the presence of a carbonyl compound (E1=R1R2CO) in THF at -78 to 0°C, followed by treatment with an epoxide [E2=R3R4C(O)CHR5] at 0 to 20°C leads, after hydrolysis, to the expected unsaturated diols 2. When some compounds 2 (2e-h) are successively hydroborated (BH3 · THF) and oxidised (33% H2O2 and then PCC), the expected perhydrofuropyrans 3e-h are isolated directly. (C) 2000 Elsevier Science Ltd.
Face Selection in Claisen Rearrangements
Mukherjee, Ashis,Wu, Qianhong,Noble, William J. le
, p. 3270 - 3274 (2007/10/02)
An investigation is reported of the stereochemistry of the Claisen rearrangement of 2-(5-phenyl-2-adamantylidene)ethyl vinyl ether (1-Ph) and of allyl (5-fluoro-2-adamatylidene)methyl ether (2-F).Both ethers undergo the rearrangement principally with the
Preparation of Crowded Olefins. Alkylidenation of Polycycloalkanones by Corey Homologative Epoxidation Followed by Reaction with Lithium Dialkylcuprates and with Thionyl Chloride
Olah, George A.,Wu, An-hsiang
, p. 887 - 889 (2007/10/02)
Preparation of crowded olefins from polycycloalkanones via Corey homologative epoxidation by trimethylsulfoxonium iodide/potassium tert-butoxide followed by reaction with lithium dialkylcuprates and thionyl chloride giving the corresponding alkylidenepoly