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The coagulation enzyme factor Xa (FXa) is a valuable target for developing anticoagulants to treat thrombotic diseases. In this work, we designed and synthesized a series of conformationally restricted compounds containing the benzo[1,3]oxazinyloxazolidinone scaffold. The target compounds were synthesized by 11 steps reaction. The preliminary SAR showed that on the phenyl ring of benzo[1,3]oxazinyloxazolidinone, lactam replacements at the 6-position were favorable for FXa inhibition. Compound 16b showed good FXa inhibitory activity with an IC50 of 0.43 μM. The results indicate that benzo[1,3]oxazinyloxazolidinone is a promising scaffold for developing FXa inhibitors as antithrombotic agents. [ABSTRACT FROM AUTHOR]

The synthesis and structure of 2,4,6,-tricyclobutyl-1,3,5-trioxane, C15H24O3 1, is described. It was formed in 39% yield during the work-up of the Swern oxidation of cyclobutylmethanol and may serve as a stable precursor of the cyclobutane carbaldehyde. The molecule of 1 occupies a special position (3.m) located at the center of its 1,3,5-trioxane ring. The latter is in a chair conformation, with the symmetry-independent O and C atoms deviating by 0.651 (4) Å from the least-squares plane of the other atoms of the trioxane ring. All three cyclobutane substituents, which have a butterfly conformation with an angle between the two planes of 25.7 (3)°, are in the cis conformation relative to the 1,3,5-trioxane ring. Intermolecular C—H...O interactions between the 1,3,5-trioxane rings consolidate the crystal structure, forming stacks along the c-axis direction. The crystal studied was refined a as a racemic twin.

Maresins are among the most potent antiinflammatory lipid metabolites. We report stereoselective syntheses of maresin 2 and maresin 2n-3 DPA. The anti -diol was constructed through epoxide ring opening of an optically active β,γ-epoxy aldehyde, synthesized in situ by Swern oxidation of the corresponding alcohol. Finally, the target compounds were synthesized through a Sonogashira coupling of a C9–C22 iodide and methyl (Z)-oct-4-en-7-ynoate or methyl oct-7-ynoate, respectively. [ABSTRACT FROM AUTHOR]

Maresins are among the most potent antiinflammatory lipid metabolites. We report stereoselective syntheses of maresin 2 and maresin 2n-3 DPA. The anti -diol was constructed through epoxide ring opening of an optically active β,γ-epoxy aldehyde, synthesized in situ by Swern oxidation of the corresponding alcohol. Finally, the target compounds were synthesized through a Sonogashira coupling of a C9–C22 iodide and methyl (Z)-oct-4-en-7-ynoate or methyl oct-7-ynoate, respectively. [ABSTRACT FROM AUTHOR]

The synthesis and structure of 2,4,6,-tri­cyclo­butyl-1,3,5-trioxane, C15H24O3 1, is described. It was formed in 39% yield during the work-up of the Swern oxidation of cyclo­butyl­methanol and may serve as a stable precursor of the cyclo­butane carbaldehyde. The mol­ecule of 1 occupies a special position (3.m) located at the center of its 1,3,5-trioxane ring. The latter is in a chair conformation, with the symmetry-independent O and C atoms deviating by 0.651 (4) Å from the least-squares plane of the other atoms of the trioxane ring. All three cyclo­butane substituents, which have a butterfly conformation with an angle between the two planes of 25.7 (3)°, are in the cis conformation relative to the 1,3,5-trioxane ring. Inter­molecular C—H∙∙∙O inter­actions between the 1,3,5-trioxane rings consolidate the crystal structure, forming stacks along the c-axis direction. The crystal studied was refined a as a racemic twin. [ABSTRACT FROM AUTHOR]

In a one pot procedure , a series of novel Triazole linked thiazolidenone derivatives 8 a-g and 9 a-g was prepared by condensation of (3aR,5S,6R,6aR)- 6-((1-(4-fluorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-2,2-dimethyltetrahydro[2,3-d][1,3]dioxole-5- carbaldehyde 7 with mercapto acids and primary amines in presence of ZnCl2 under both micro wave irradiation and conventional heating conditions. Compound 7 prepared from di Acetone D- Glucose with oxidation followed by reduction , click reaction, primary acetonide deprotection and with oxidative cleavage .Characterization of new compounds has been done by means of IR, NMR, MS and elemental analysis. The nematicidal and anti bacterial activity of the compounds has also been evaluated.

The total synthesis of 16-membered C2–Symmetric dilactone (-)-Pyrenophorol was accomplished starting from commercially available (S)-epoxide prepared by hydrolytic kinetic resolution of (±) – epoxide with key steps of Grignard reaction, Swern oxidation, Wittig reaction and cyclization was achieved by intermolecular Mitsunobu cyclization. The synthesis of (-)-Pyrenophorol accomplished from cheaply available starting material, easily work-up procedures and reduction of cost in industrial process were major advantages of this route. [ABSTRACT FROM AUTHOR]

Swern oxidation is widely used to convert alcohols into their corresponding carbonyl compounds. However, the conventional method with use of the volatile oxalyl chloride as an activator requires the reaction to be conducted below -60 °C. We discovered that 3,3-dichloro- 1,2-diphenylcyclopropene (DDC) can be used as a new activator for Swern-type oxidations of alcohols, which can be conducted at -20 °C. This new protocol features mild and fast reactions with easy operation. Furthermore, the activator DDC is easy to handle, and diphenylcyclopropenone can be recovered quantitively. This new type of Swern oxidation shows a broad scope of substrates including benzylic, allylic, aliphatic, and biobased alcohols, and gives high yields of up to 93%. [ABSTRACT FROM AUTHOR]

Abstract: Lignin, the planet's most abundant renewable source of aromatic compounds, is difficult to degrade efficiently to welldefined aromatics. We developed a microwave‐assisted catalytic Swern oxidation system using an easily prepared catalyst, MoO2Cl2(DMSO)2, and DMSO as the solvent and oxidant. It demonstrated high efficiency in transforming lignin model compounds containing the units and functional groups found in native lignins. The aromatic ring substituents strongly influenced the selectivity of β‐ether phenolic dimer cleavage to generate sinapaldehyde and coniferaldehyde, monomers not usually produced by oxidative methods. Time‐course studies on two key intermediates provided insight into the reaction pathway. Owing to the broad scope of this oxidation system and the insight gleaned with regard to its mechanism, this strategy could be adapted and applied in a general sense to the production of useful aromatic chemicals from phenolics and lignin. [ABSTRACT FROM AUTHOR]

Preparation of benzaldehyde by Swern oxidation of benzyl alcohol was carried out in a continuous ow microreactor system. Dimethyl sulfoxide (Me2 SO) was used as oxidizing agent and oxalyl chloride or p-toluenesulfonyl (p-TsCl) chloride was used as the activating agent. Benzyl alcohol was oxidized to benzaldehyde by the Me2 SOactivating agent mixture in the continuous ow microreactor system. The optimized reaction conditions of the Swern oxidation were as follows: oxalyl chloride was used as the activating agent; the mole ratio of Me2SO, oxalyl chloride, and benzyl alcohol was 4:2:1; the ow rate of Me2SO was 1.5 mL/min; the reaction temperature was 15°C; length of delay loop was 1.5 m; a Caterpillar Split-Recombine Micro Mixer was used; and all of the experiments were completed at atmospheric pressure. The yield of benzaldehyde can reach 84.7% with selectivity of 98.5%. Due to the small reactor volume and short residence times, the Swern oxidation of benzyl alcohol in a continuous ow microreactor system can be operated at nearly room temperature (5{19°C) instead of {70°C in a batch reaction, with residence time of reactants in microreactors in milliseconds instead of several hours in a batch reaction. [ABSTRACT FROM AUTHOR]

A series of 4-hydroxyl-Δ2-isoxazol-6(6aH)-one derivatives was prepared by magnesium ion-mediated diastereoface-selective 1,3-dipolar cycloaddition of aromatic nitrile oxides with pyrrolidinone derivatives. The reaction of 4-hydroxyl-Δ2-isoxazol-6(6aH)-one derivatives with dimethylsulfoxide and oxalyl chloride under Swern conditions led to a Δ2-isoxazole-4,6(5H,6aH)-dione.

In a one pot procedure a series of novel triazole linked thiazolidinone derivatives 8a-g and 9a-g was prepared by condensation of (3aR,5S,6R,6aR)-6-((1-(4-chlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-2,2-dimethyltetrahydro[2,3-d] [1,3]dioxole-5-carbaldehyde 7 with mercapto acids and primary amines in the presence of ZnCl2 under both microwave irradiation and conventional heating conditions. Compound 7 was prepared from diacetone D-glucose with oxidation followed by reduction, click reaction, primary acetonide deprotection and with oxidative cleavage. Characterization of new compounds has been done by means of IR, NMR, MS and elemental analysis. The nematicidal and antibacterial activity of the compounds has also been evaluated. [ABSTRACT FROM AUTHOR]

The first total synthesis of neurotrophic diacetylenic tetraol, petrosiol A and stereoselective total synthesis of petrosiol E was accomplished. The total synthesis involves Cadiot-Chodkiewicz coupling reaction as the key step for petrosiol A. The diastereorich chiral alcohol (third chiral center) was synthesized from CBS mediated stereoselective ketone reduction reaction for petrosiol E. Of the three chiral centers, the two chiral centers are originated from (+)-diethyl l -tartrate and the third chiral center was generated by an addition reaction of lithium trimethylsilylacetylide leading to two diastereomers which were used for the synthesis of both the natural products and their diastereomer C6- epi -petrosiol A and C6- epi -petrosiol E, respectively. [ABSTRACT FROM AUTHOR]

A new type of sulfoxide, 4-(2-(2-(methylsulfinyl) ethyl)-4-nitrophenyl)- morpholine (I), was designed and prepared in good yield. Upon the combination ofIandbis(trichloromethyl)carbonate, the Swern oxidation of primary and secondary alcohols was significantly promoted under mild conditions, which afforded the corresponding aldehydes or ketones in good yields. It is noteworthy that the reoxidation of the isolated by-product sulfide V could be further recycled in Swern oxidation. [ABSTRACT FROM PUBLISHER]

An environmentally benign approach for one-pot synthesis of 3,4-dihydropyrimidin- 2-(1H)-ones derivative (DHPMs) using ethyl acetoacetate, urea and benzyl alcohol instead of aldehyde under microwave cavity is described. This one-pot oxidation-cyclocondensation protocol based on the Swern oxidation was performed in presence of Bi(NO3)2 without isolation of any intermediate (aldehyde) and thus reducing time, energy and raw materials with good yield of product. This study gave a new strategy of synthesis i.e by employing microwave as a tool in order to diminish reaction time and to avoid side products with increased yield and simplicity of the course of reaction. All the reported reactions were also pursued via conventional methods for a comparative study. The results obtained confirmed the superiority of the microwave irradiation method over the classical reflux heating. The compound was characterized by spectral analysis using UV, FTIR and GC-MS techniques. [ABSTRACT FROM AUTHOR]

A facile and convergent approach for the total synthesis of 14-membered resorcylic acid lactone paecilomycin F is described. The synthesis emanates from the readily available inexpensive (+)-diethyl L-tartrate. Mitsunobu etherification, Stille coupling and ring-closing metathesis are key steps in the synthesis. [ABSTRACT FROM AUTHOR]

An efficient asymmetric synthetic route for the synthesis of anti-glaucoma agent, (15R)-latanoprost using Corey lactone diol as chiral substrate under Swern oxidation, allylic reduction and Wittig reaction conditions has been developed. In this method, reduction of keto and alkene functional groups has been achieved in a single step using low cost catalyst NiCl/NaBH in methanol. This new synthetic protocol is a good alternative for the synthesis of latanoprost with high stereo selectivity and improved yield. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

An improved synthesis of bicyclo[2.2.1]hept-5-ene-2,3-dione by Swern oxidation of bicyclo[2.2.1]hept-5-ene-2,3-diol, and an unexpected ring-opening reaction by the Swern oxidation of pyrazine-fused congeners are described.

A new dimethylsulfoxide activation method employing 1,1-dichlorocycloheptatriene has been developed for a mild Swern-type oxidation of a variety of alcohols. The carbonyl products can be obtained in good to excellent yields from this operationally simple and efficient method. This work is the first report of dimethylsulfoxide activation by a simple chlorinated hydrocarbon reagent, which has the unique ability of equilibrating to its reactive aromatic cationic form. [ABSTRACT FROM AUTHOR]

A practical and efficient alternative version of the Swern oxidation has been successfully developed. Methyltrichlorosilane was used as an efficient activator of dimethylsulfoxide, which could oxidize a wide range of primary and secondary alcohols to the corresponding carbonyl compounds with good to excellent yields. [ABSTRACT FROM PUBLISHER]

Highlights: [•] A simple, efficient and stereoselective synthesis of KDG isopropyl ester. [•] Synthesis ofKDG isopropyl ester via controlled epimerization and a two-step reaction sequence. [•] KDG isopropyl ester specifically promotes growth of ammonium producing bacterial strains. [ABSTRACT FROM AUTHOR]

1,3-Dipolar cycloaddition reaction of 2-diazopropane1with 1,4-benzoquinone2carried out at −20 °C led to a minor mono-cycloadduct4and mixture of bis-cycloadducts6and7. The same addition realized with 3H-pyrazole7at −60 °C for 2 h yields a mixture of compounds8and9and results inO-alkylation. The reaction of 3H-pyrazoles4and7with dimethylsulfoxide and oxalyl chloride under Swern conditions led to pyrazolenines11and12. [ABSTRACT FROM PUBLISHER]

A stereoselective total synthesis of multiplolide A ( 1) and of its diastereoisomer 2 was described from easily accessible starting materials ( Schemes 2- 4). The synthetic strategy involves a Jacobsen resolution, Sharpless epoxidation, Swern oxidation, Yamaguchi reaction, and ring-closing metathesis (RCM). [ABSTRACT FROM AUTHOR]

This study describes an improved one-pot, four-step synthesis of a new series of 1-aryl-3-trifluoroacetyl pyrroles from the reaction of 3-trifluoroacetyl-4,5-dihydrofuran with arylamines, giving 1,1,1-trifluoro-3-(2-hydroxyethyl)-4-arylamino-3-buten-2- ones, which were directly submitted to Swern oxidation to furnish 1,1,1-trifluoro-3-(2-ethanal)-4-arylamino-3-buten-2-ones. Subsequent intramolecular cyclization of the corresponding enaminoaldehydes followed by aromatization rendered the title compounds in a 30 to 56% overall yield. [ABSTRACT FROM AUTHOR]

Abstract: The enantioselective synthesis of oxylipin-3 has been carried out. The synthetic strategy was started from commercially available n-decanal. The chiral source was based on Sharpless asymmetric dihydroxylation and CBS reduction. [Copyright &y& Elsevier]

Abstract: De novo incorporation of N-formylated aminols as strategic substrates in legendary Ugi cyclization. Lactamization of N-formido alkanols is accomplished by a novel Parikh–Doering oxidation–dehydration–Ugi cyclization cascade leading to the formation of lactams up to eight carbons (ring size; n=1–4) in moderate yields using formidoaminol, substituted aniline, and aliphatic/aromatic carboxylic acid derivatives as starting materials. [Copyright &y& Elsevier]

The oxidation of primary and secondary alcohols with ion-supported methyl sulfoxide and oxalyl chloride in the presence of triethylamine in dichloromethane efficiently proceeded to give the corresponding aldehydes and ketones, respectively, in good yields with high purity. Isolation of the product was achieved very easily by simple diethyl ether extraction of the reaction mixture and subsequent removal of solvent from the extract. The reaction did not produce any unpleasant odor. Furthermore, ion-supported methyl sulfide was recovered in good yield and could be re-oxidized to ionsupported methyl sulfoxide for reuse in the same oxidation. [ABSTRACT FROM AUTHOR]

Abstract: 1,3-Dipolar cycloaddition of 2-diazopropane to conjugated dienes 1 and α,β-unsaturated ketones 5 is taking place regiospecifically to give cycloadduit 4 and 6. The reaction of 2-pyrazolines derivatives with dimethylsulfoxide and oxalyl chloride under Swern conditions led to a pyrazolenines 7 and 8. [Copyright &y& Elsevier]

Abstract: A number of unexpected reactions were observed during attempts to invert configuration at C16 in 16α,17α,22-triol 3a. The PDC oxidation of 3a produced the D-seco-aldehyde 4a. Analogous compound 4b was obtained by Swern oxidation of the 16α,17α-dihydroxy-22-O-TES-ether 3b in addition to the desired 16-ketone 7. The unprotected triol 3a yielded pentacyclic products 5 and 6 under similar conditions. The Mitsunobu reaction of the triol 3a afforded 16-ketone 8 with inverted configuration of the side chain. During heating of a solution of 3a in THF with NaH at reflux autoxidation to the 16-ketone cyclic hemiketal 5, identical to one of the Swern oxidation products, took place. [Copyright &y& Elsevier]

The synthesis of several 1-substituted cis-bicyclo[3.3.0]octane-3,7-dione derivatives as potential precursors of a triquinacene having a pyramidalized C=C bond from ethyl cis-3,7-dioxobicyclo-[3.3.0]octane-1-carboxylate is described. [ABSTRACT FROM AUTHOR]

An efficient procedure for conversion of alcohols to the corresponding carbonyl compounds, an alternative to the classical Swern oxidation, is described. Pivaloyl chloride is employed as a mild and inexpensive electrophile. A possible reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]

A variety of alcohols have been oxidized under mild conditions by a dimethylsulfoxide (DMSO)-chlorophosphazene complex. Sensitive groups such as silyl and tetrahydropyranyl (THP) ethers are stable under this condition. [ABSTRACT FROM AUTHOR]

We describe a new efficient synthesis of the prescribed racemic drug cetiedil [(�)-2-cyclohexyl-2-(3-thienyl)ethanoic acid 2-(hexahydro-1H-azepin-1-yl)ethylester]. Additionally, we report herein a high yielding large scale, route to its acid precursor 7, subsequently enabling large-scale synthesis of the chiral forms of cetiedil, and detailed pharmacological investigations. Additionally, we describe a novel route to α-ketocarboxylic acids, starting from readily available or easily obtainable aldehydes: The mild conditions utilised opens up its applicability for use on molecules of biological interest. [ABSTRACT FROM AUTHOR]

A method for the rapid synthesis of psoralen and 4-methylpsoralen has been developed. The key intermediates, coumarinyloxyaldehydes, were obtained in only two steps from the easily available starting materials, 7-hydroxycoumarin derivatives, by an oxidative procedure. By using Swern oxidation, psoralen and 4-methylpsoralen were finally produced in the overall yields of 71% and 67%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A facile method for the solid-phase synthesis of pyrrolo[2,1-c][1,4]benzodiazepine dimers has been developed. p-Nitrophenyl carbonate Wang resin attached to 2-amino-5-methoxy-methyl benzoate has been utilized as the resin-bound starting material and these reactions are monitored by FT-IR spectroscopy of resin beads. [Copyright &y& Elsevier]

Abstract: A new class of odorless and non-volatile organosulfur compounds grafted to imidazolium ionic liquid scaffold has been synthesized. The sulfoxides can be used effectively for the oxidation of primary allylic and benzylic alcohols into aldehydes and secondary alcohols to ketones under Swern oxidation conditions and the corresponding sulfides can be recovered and recycled. [Copyright &y& Elsevier]

Abstract: X-ray crystallographic studies performed on the product of the ketalization reaction of 13β-ethyl-11α-hydroxy-gon-5-ene-3,17-dione have lead to the unequivocal assignment of the 10α stereochemistry to C10, showing that an inversion of configuration occurred during formation of the 3,17-diketal. From the Swern oxidation of this compound, 11α-(methylthio)methoxy-10α-gonene was obtained as the major product instead of the desired 11-ketone. Modeling studies showed that the configurational instability at C10 is determined by the presence of the 11α-hydroxyl group. [Copyright &y& Elsevier]

Abstract: Various 2-arylmethylimidazolines were prepared by treating readily available 2-aryl-1,1-dibromoethenes with ethylenediamine under mild conditions and further converted into the corresponding imidazoles smoothly with Swern oxidation. [Copyright &y& Elsevier]

Two new soluble polystyrene-based sulfoxide reagents are introduced. These polymeric reagents are used in Swern oxidation reactions where the resulting sulfide polymers are easily separated from the product by simple precipitation and filtration. The recovered reduced polymer reagents can be recycled by oxidation with tert-butyl hydroperoxide in the presence of acid. Attempts to use these reagents in a multi-polymer Swern oxidation reaction system were unsuccessful. [Copyright &y& Elsevier]

The total synthesis of the polyenoyltetramic acid polycephalin C is described. Key steps of the synthesis include a double Swern oxidation, double Takai reaction and a double Stille reaction. In addition, the absolute stereochemistry of the ring junction has been determined by synthesis of both isomers and comparison of their CD spectra with natural polycephalin C. [Copyright &y& Elsevier]

A new synthesis of tert-butyl [(4R,6R)-6-aminoethyl-2,2-dimethyl-1,3-dioxan-4-yl]acetate, a key intermediate of the synthesis of an effective HMG-CoA reductase inhibitor atorvastatin, is described. The synthesis is based on the Henry reaction of nitromethane and tert-butyl [(4R,6S)-6-formyl-2,2-dimethyl-1,3-dioxan-4-yl] acetate. The formed nitroaldol was then O-acetylated and the sodium borohydride reduction of the intermediate provided tert-butyl [(4R,6R)-2,2-dimethyl-6-nitroethyl-1,3-dioxan-4-yl] acetate. Catalytic hydrogenation of the nitro group led to the title compound. [ABSTRACT FROM AUTHOR]

Abstract: An efficient synthesis of cis-2,6-di-(2-quinolylpiperidine) has been developed. The key steps involve Wittig reaction of N-Cbz-protected cis-piperidine-2,6-dicarboxaldehyde (3) with 2-(triphenylphosphinyl-methyl)quinoline bromide (4) and sequential removal of the N-Cbz group and double bond reduction. This synthetic procedure provides an efficient preparation for this useful norlobelane analogue. [Copyright &y& Elsevier]

The protecting group free synthesis of Anomala Osakana Pheromone isomer has been achieved with high enantioselectivity (92% ee). A chiral γ-hydroxy-α, β-acetylenic ester was used as the key intermediate, which was obtained via asymmetric alkynylation of aldehyde. This was followed by readily handled selective hydrogenation and lactonization in three steps with a high overall yield (86%). [ABSTRACT FROM AUTHOR]

Abstract: A rapid, mild and high yielding method for the synthesis of methylthiomethyl esters is reported from the corresponding aliphatic, aromatic and unsaturated carboxylic acids under Swern oxidation conditions using dimethylsulfoxide, oxalyl chloride and triethylamine at low temperature. [Copyright &y& Elsevier]

Abstract: An efficient utilisation of RCM leading to a convenient synthesis of a pentacyclic indole alkaloid is described. [Copyright &y& Elsevier]

Using a copper-catalyzed coupling reaction of amino acid and aryl halide, followed by intramolecular cyclization of N-aryl-1-hydroxyl-3-propylamines under the Swern’s condition as the key steps, (S)-2-hydroxymethyl-1,2,3,4-tetrahydroquinoline was synthesized as an example of optically pure 2-functionalized 1,2,3,4-tetrahydroquinolines. [Copyright &y& Elsevier]