- Asymmetric Bayer-Villiger oxidation of cyclobutanones
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The asymmetric Baeyer-Villiger oxidation of racemic cyclobutanones 1, 2, and 3 and a prochiral cyclobutanone 4 under Sharpless oxidation conditions resulted in the enantiomeric lactones 5 ee 34%, 6 ee 53%, 7 ee 75% and 8 40% ee respectively.
- Lopp, Margus,Paju, Anne,Kanger, Tonis,Pehk, Tonis
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- Radical addition of 2-iodoalkanamide or 2-iodoalkanoic acid to alkenols using a water-soluble radical initiator in water. A facile synthesis of γ- lactones
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Heating a mixture of 2-iodoacetamide and 5-hexen-1-ol in water at 75 °C in the presence of a water-soluble radical initiator, 4,4'-azobis(4- cyanopentanoic acid), provided γ-(4-hydroxybutyl)-γ-lactone in 95% yield. The use of 2-iodoacetic acid in place of
- Yorimitsu, Hideki,Wakabayashi, Katsuyu,Shinokubo, Hiroshi,Oshima, Koichiro
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- THE TRANSFORMATION OF ALKENES INTO γ-LACTONES USING α-IODOESTERS
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Iodostannyl esters react with alkenes in the presence of AIBN to afford γ-lactones.
- Kraus, George A.,Landgrebe, Kevin
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- DEPLACEMENTS HOMOLYTIQUES INTRAMOLECULAIRES : V - EPOXY-2,3 PROPANATION DES ACIDES ET DERIVES PAR THERMOLYSE DU PEROXYDE D'ALLYLE ET DE t-BUTYLE
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The thermolysis of the allyl t-butylperoxide has been performed in esters, acids, anhydrides, nitriles and amides.Only esters and acetonitrile have been 2,3-epoxy propanated.With acids, the reaction product is the alkanoate of the hydroxymethyl-γ-butyrolactone corresponding to the cyclization of the expected epoxyacid and it is isolated with a good yield; the same compound is obtained putting the anhydride in place of the acid.
- Montaudon, E.,Rakotomanana, F.,Maillard, B.
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- Radical addition of 2-iodoalkanamide or 2-iodoalkanoic acid to alkenes with a water-soluble radical initiator in aqueous media: Facile synthesis of γ-lactones
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Radical reactions in water or aqueous ethanol using a water-soluble radical initiator are described. Heating a mixture of 2-iodoacetamide and 5-hexen-1-ol in water at 75 °C in the presence of a water-soluble radical initiator, 4,4′-azobis 4-cyanopentanoic acid), afforded 5-(4-hydroxybutyl)dihydrofuran-2(3H)-one in 95% yield. The use of 2-iodoacetic acid in place of 2-iodoacetamide also gave the same γ-lactone in 93% yield. The reaction of 2-iodoacetamide with 1-octene in aqueous ethanol was initiated by 2,2′-azobis(2-methylpropanamidine) dihydrochloride to provide γ-decanolactone. Employing water as a solvent is crucial to obtain lactone in satisfactory yield.
- Yorimitsu,Wakabayashi,Shinokubo,Oshima
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- Synthesis of functionalized γ-and δ-lactones via polymer-bound epoxides
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Solid phase synthesis of epoxides from alkenoic acids followed by ring-opening reactions with sodium azide or thiophenols and subsequent cleavage from the polymeric support afford γ- and δ-lactones in good yields and high purity.
- Le Hetet, Claire,David, Michelle,Carreaux, Francois,Carboni, Bertrand,Sauleau, Armelle
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- Heterogeneous Permanganate Oxidation of 1,5-Dienes: A Novel Synthesis of 5-Substituted Butanolides
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In the presence of a catalytic amount of water, 1,5-dienes undergo novel and unusual oxidation with potassium permanganate-copper sulfate in dichloromethane to give substituted butanolides in good yields under very mild conditions.
- Baskaran, Sundarababu,Islam, Imadul,Vankar, Padma S.,Chandrasekaran, Srinivasan
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- Efficient Catalysts for the Green Synthesis of Adipic Acid from Biomass
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Green synthesis of adipic acid from renewable biomass is a very attractive goal of sustainable chemistry. Herein, we report efficient catalysts for a two-step transformation of cellulose-derived glucose into adipic acid via glucaric acid. Carbon nanotube-supported platinum nanoparticles are found to work efficiently for the oxidation of glucose to glucaric acid. An activated carbon-supported bifunctional catalyst composed of rhenium oxide and palladium is discovered to be powerful for the removal of four hydroxyl groups in glucaric acid, affording adipic acid with a 99 % yield. Rhenium oxide functions for the deoxygenation but is less efficient for four hydroxyl group removal. The co-presence of palladium not only catalyzes the hydrogenation of olefin intermediates but also synergistically facilitates the deoxygenation. This work presents a green route for adipic acid synthesis and offers a bifunctional-catalysis strategy for efficient deoxygenation.
- Deng, Weiping,Yan, Longfei,Wang, Binju,Zhang, Qihui,Song, Haiyan,Wang, Shanshan,Zhang, Qinghong,Wang, Ye
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- Epoxidation of alkenes bearing a carboxylic acid group by iron complexes of the tetradentate ligand N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)-1, 2-diaminoethane and its derivatives
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The addition of carboxylic acids enhances the rate and selectivity of alkene oxidations catalyzed by [(bpmen)Fe(OTf)2] (bpmen = N,N′-dimethyl-N,N′-bis(2-pyridylmethyl)-1,2-diaminoethane). The syntheses and characterizations of four derivatives of this iron complex with varying substitutions on the pyridine ring and with a substituted piperazine backbone are reported. These [(L)Fe(OTf)2] complexes and [(bpmen)Fe(OTf)2] are employed as catalysts for the oxidation of alkenes bearing a carboxylic acid functional group, namely oleic acid, undecylenic acid, 5-hexenoic acid and 4-pentenoic acid, with hydrogen peroxide as the oxidant. Comparisons with the analogous ester substrates demonstrate the beneficial impact of the acid functional group on conversion and selectivity when using [(bpmen)Fe(OTf)2] as a catalyst. For the oleic and undecylenic acids, epoxide product is formed with moderate to high conversions and high selectivities. Under the conditions employed, 4-pentenoic acid is oxidized to a γ-lactone, most likely via the epoxide intermediate, and 5-hexenoic acid to a mixture of epoxide and δ-lactone. Of the iron complexes with bpmen derivatives as ligands, only the N,N′-dimethyl-N, N′-bis(5-chloropyridin-2-ylmethyl)-1,2-diaminoethane variant shows appreciable activity. The effect of solvent choice is also investigated.
- Morris, Lilliana S.,Girouard, Michael P.,Everhart, Matthew H.,McClain, William E.,Van Paridon, John A.,Pike, Robert D.,Goh, Christopher
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- Method for preparing 5-hydroxymethyldihydrofuran-2-one by taking furfural as raw material
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The invention discloses a method for preparing 5-hydroxymethyldihydrofuran-2-one by using furfural as a raw material, and relates to a preparation method of an organic chemical raw material. The method is as follows: furfural is used as a raw material, ethanol is used as a solvent, a Raney nickel catalyst is used, and tetrahydrofurfuryl alcohol is prepared by catalytic hydrogenation reduction; gamma-Al2O3 is taken as a carrier, cerium nitrate and silver nitrate are taken as raw materials, and an Ag/CeO2/Gamma-Al2O3 catalyst is prepared by adopting an impregnation method, a roasting method anda natural cooling method; and the prepared tetrahydrofurfuryl alcohol is used as a raw material, the prepared Ag/CeO2/gamma-Al2O3 catalyst is adopted, and oxygen is introduced for a reaction to obtain5-hydroxymethyl dihydrofuran-2-one. The method is beneficial to improving the product selectivity; the catalyst is prepared by adopting a dipping-roasting method, the method is simple, the dispersityof active metal elements is good, and the product selectivity is high; and the product 5-hydroxymethyldihydrofuran-2-one has hydroxyl, furan ring and keto functional groups, is a raw material for synthesizing a plurality of antiviral, anticancer and anti-AIDS medicines, and has the advantages of high added value, high economic benefit and high social benefit.
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Paragraph 0022-0027
(2020/07/02)
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- N-SUBSTITUTED TETRAHYDROTHIENOPYRIDINE DERIVATIVES AND USES THEREOF
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A compound of Formula (I) is provided that has been shown to be useful for treating a disease caused by a viral infection: (I) wherein R1, R2, R3, A, L, m, n, p and q are as defined herein.
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- NITRIC OXIDE-RELEASING PRODRUG MOLECULE
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Provided are a type of compounds that can be used for treating cardiovascular diseases and compositions containing the compounds. The compounds and the compositions can improve lipid metabolism disorders by increasing high-density lipoprotein cholesterol in blood; in addition, the compounds and the compositions can also release nitric oxide, and reduce the onset risk of cardiovascular diseases by means of relaxing blood vessels, lowering blood pressure, inhibiting platelet adhesion and aggregation and maintaining vascular tension, and thus play an important role in preventing and treating the occurrence and development of cardiovascular diseases.
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Paragraph 0079
(2018/08/01)
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- Method for synthesizing zidovudine-1,2,3-triazole compound
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The invention discloses a method for synthesizing a zidovudine-1,2,3-triazole compound, belonging to the technical field of antibacterial active medicines. According to the technical scheme of the invention, the specific route of the method for synthesizing the zidovudine-1,2,3-triazole compound is as shown in the specification. According to the method, on the basis that zidovudine molecules comprise azide groups, click reaction can be performed to enable zidovudine to react with aniline allylene compounds with different substituent groups so as to obtain the zidovudine-1,2,3-triazole compound, moreover gram-positive bacterium-staphylococcus aureus, gram-negative bacterium-escherichia coli and fungus-candida albicans are selected to perform in-vitro antibacterial activity testing on the zidovudine-1,2,3-triazole compound, and the results show that the compound has relatively good antibacterial activity.
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Paragraph 0037; 0038; 0039
(2017/08/29)
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- Preparation method of 2,5-piperidione
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The invention relates to a preparation method of 2,5-piperidione. 2-glutamic acid is used as a starting raw material to perform closed loop reaction to produce a compound 2 under the effects of NaNO2; a compound 3 is produced through borane reduction; a compound 4 is produced under the effects of methylsufonyl chloride; a compound 5 is produced through substitution under the sodium azide effect; a compound 6 is produced through Pd/H2 under the reduction effect; a target compound is generated under the effect of Dess-Martin periodinane. The preparation method has the advantages that the raw materials are cheap and can be easily obtained; the synthetic method is simple; the method belongs to a fire-new method for synthesizing 2,5-piperidione. The method meets the requirements of large-scale industrial production.
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Paragraph 0022; 0023; 0025; 0030
(2017/07/26)
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- Zidovudine derivative with antimicrobial activity and preparation method and application thereof
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The invention discloses a zidovudine derivative with the antimicrobial activity and a preparation method and application thereof, and belongs to the technical filed of synthesis of drugs with antimicrobial activity. The zidovudine derivative with the antimicrobial activity is technologically characterized in that the structural formula of the zidovudine derivative with the antimicrobial activity is shown in the specification, wherein R in the structural formula is C1-4 alkyl or halogen atoms. The invention further discloses a specific synthesis process of the zidovudine derivative with the antimicrobial activity and the application of the zidovudine derivative with the antimicrobial activity in antibacterial drug preparation. According to the zidovudine derivative with the antimicrobial activity, zidovudine molecules contain azide groups and are subjected to the click reaction with aniline polyacetylenes with different substituent groups, so that the zidovudine derivative is obtained; and gram-positive bacterium-staphylococcus aureus and Gram-negative bacterium-escherichia coli and fungus-Candida albicans are selected to be used for measuring the in-vitro antimicrobial activity of the synthesized zidovudine derivative, and the result shows that the zidovudine derivative has good antimicrobial activity.
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Paragraph 0030; 0039; 0040; 0041
(2017/08/28)
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- Fe(PyTACN)-catalyzed cis-dihydroxylation of olefins with hydrogen peroxide
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A family of iron complexes with general formula [Fe(II)( R,Y,XPyTACN)(CF3SO3)2], where R,Y,XPyTACN=1-[2′-(4-Y-6-X-pyridyl)methyl]-4,7-dialkyl-1,4, 7-triazacyclononane, X and Y refer to the groups at positions 4 and 6 of the pyridine, respectively, and R refers to the alkyl substitution at N-4 and N-7 of the triazacyclononane ring, are shown to be catalysts for efficient and selective alkene oxidation (epoxidation and cis-dihydroxylation) employing hydrogen peroxide as oxidant. Complex [Fe(II)(Me,Me,HPyTACN)(CF 3SO3)2] (7), was identified as the most efficient and selective cis-dihydroxylation catalyst among the family. The high activity of 7 allows the oxidation of alkenes to proceed rapidly (30 min) at room temperature and under conditions where the olefin is not used in large amounts but instead is the limiting reagent. In the presence of 3 mol% of 7, 2 equiv. of H2O2 as oxidant and 15 equiv. of water, in acetonitrile solution, alkenes are cis-dihydroxylated reaching yields that might be interesting for synthetic purposes. Competition experiments show that 7 exhibits preferential selectivity towards the oxidation of cis olefins over the trans analogues, and also affords better yields and high [syn-diol]/[epoxide] ratios when cis olefins are oxidized. For aliphatic substrates, reaction yields attained with the present system compare favourably with state of the art Fe-catalyzed cis-dihydroxylation systems, and it can be regarded as an attractive complement to the iron and manganese systems described recently and which show optimum activity against electron-deficient and aromatic olefins. Copyright
- Prat, Irene,Font, David,Company, Anna,Junge, Kathrin,Ribas, Xavi,Beller, Matthias,Costas, Miquel
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supporting information
p. 947 - 956
(2013/05/08)
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- A new solid-phase reaction system utilizing a temperature-responsive catalyst: Oxidative cyclization with hydrogen peroxide
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A switchable catalyst based on temperature change provides a novel solid-phase reaction system in water. An increase in catalyst affinity for organic substrates at higher temperature led to efficient activity driving the solid inner-phase reaction, and loss of affinity at lower temperature allowed easy separation of organic products upon completion of the reaction. Application of this catalyst intelligence to design a novel catalytic system brought about an efficient oxidative cyclization with hydrogen peroxide, a useful method of accessing oxygen heterocycles.
- Hamamoto, Hiromi,Suzuki, Yachiyo,Takahashi, Hideyo,Ikegami, Shiro
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p. 2685 - 2689
(2008/09/20)
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- On the phenyliodine(III)-bis(trifluoroacetate)-mediated olefin amidohydroxylation reaction
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When appropriately substituted amides are treated with PIFA in a non-nudeophilic solvent like trifluoroethanol, a stable N-acylnitrenium ion is generated. If under such conditions a C=C double bond is present in the molecule, an intramolecular cyclization
- Tellitu, Imanol,Urrejola, Andrea,Serna, Sonia,Moreno, Isabel,Herrero, M. Teresa,Dominguez, Esther,SanMartin, Raul,Correa, Arkaitz
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p. 437 - 444
(2008/02/03)
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- Intramolecular PIFA-mediated alkyne amidation and carboxylation reaction
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(Chemical Equation Presented) The hypervalent iodine reagent PIFA promotes the intramolecular electrophilic cyclization of easily accessible alkynylamides and alkynyl carboxylic acids, leading to the formation of pyrrolidinone and lactone skeletons, respe
- Tellitu, Imanol,Serna, Sonia,Herrero, M. Teresa,Moreno, Isabel,Dominguez, Esther,SanMartin, Raul
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p. 1526 - 1529
(2007/10/03)
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- PROCESS FOR PRODUCING HYDROXYLACTONE
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A process of the present invention produces a hydroxylactone by subjecting an unsaturated carboxylic acid having a double bond not conjugated to a carboxyl group or an ester thereof to (i) a reaction with hydrogen peroxide in the presence of a metallic compound containing a metallic element selected from W, Mo, V and Mn or (ii) a reaction with a peroxide containing the metallic element to thereby yield a corresponding hydroxylactone having a hydroxyl group combined with one of carbon atoms constituting the double bond and being cyclized at the other carbon atom position. The metallic compound may be one selected from oxides, oxoacids and salts thereof. The unsaturated carboxylic acid includes, for example, β,γ-unsaturated carboxylic acids, γ,δ-unsaturated carboxylic acids, and δ,ε-unsaturated carboxylic acids. The process can produce hydroxylactones in high yields at low cost.
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- Anti-viral compounds
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Nucleotide analogues having the general formula (I) and pharmaceutically acceptable derivatives: STR1 wherein n is 0 or an integer; X is O or S, CH2, CH-halogen, CH--N3, or C=CH2 ; Q and U are independently selected from: O, S, and CH(Ra) wherein Ra is hydrogen, OH, halogen, N3, NH2, SH, carboxyl, C1-6 alkyl or Ra is CH2 (Rb) wherein Rb is hydrogen, OH, SH, NH2, C1-6 alkyl or carboxyl; or both Q and U are CH when Q and U are linked by a double bond; Z is selected from: O, a C1-6 alkoxy, a C1-6 thioalkyl, a C1-6 aminoalkyl, (CH2)m wherein m is 0 or an integer, and N(Rc)2 wherein both Rc are independently hydrogen or a C1-6, alkyl; and R2 is a purine or pyrimidine base or an analogue or derivative thereof are disclosed. Members of this series of analogues possess anti-viral activity.
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- Expeditious syntheses of sugar-modified nucleosides and collections thereof exploiting furan-, pyrrole-, and thiophene-based siloxy dienes
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A series of individual sugar-modified pyrimidine nucleosides including enantiomerically enriched 2',3'-dideoxynucleosides 14a-c (α and β anomers of L- and D-series), 2',3'-dideoxy-4'-thionucleosides 21a-c (α and β anomers of L- and D-series), and 2',3'-dideoxy-4'-azanucleosides 28a-c (β anomers of L- and D-series) were synthesized, with uniform chemistry and high stereochemical efficiency, exploiting a triad of versatile heterocyclic siloxy dienes, namely, 2-(tert-butyldimethylsiloxy)furan (TBSOF), 2-(tert- butyldimethylsiloxy)thiophene (TBSOT), and N-(tert-butoxycarbonyl)-2-(tert- butyldimethylsiloxy)pyrrole (TBSOP). The synthetic procedure advantageously used both enantiomers of glyceraldehyde acetonide (D-1 and L-1) as sources of chirality and as synthetic equivalents of the formyl cation. The outlined chemistry also allowed for the rapid assemblage of a 30-member collection of racemic nucleosides (D,L-L) as well as one 15-member ensemble of chiral analogues (L-L), along with some related sublibraries.
- Rassu, Gloria,Zanardi, Franca,Battistini, Lucia,Gaetani, Enrico,Casiraghi, Giovanni
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p. 168 - 180
(2007/10/03)
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- STANNYL ESTER CYCLIZATIONS
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Alpha halo stannyl esters react with alkenes to afford lactones.The reaction is catalyzed by AIBN.The reaction proceeds best with electron rich alkenes.The mechanistic aspects of this novel reaction are discussed.This reaction can also be conducted intramolecularly to produce bicyclic lactones.An approach to the lignan system is presented.
- Kraus, George A.,Landgrebe, Kevin
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p. 4039 - 4046
(2007/10/02)
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- Process for preparing unsaturated six-membered lactones
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There are disclosed and claimed substituted cyclic lactones and process for preparation thereof. In particular, there are disclosed substituted cyclic lactones having alkyl substituents on the ring, especially such lactones having substituents on the ring of which two on the same carbon atom. Additionally, the invention herein disclosed and claimed relates to a process for the preparation of lactones by heating a six-membered hydroxy substituted lactone in the presence of a catalyst.
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- Substituted lactones and processes for their preparation
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There are disclosed substituted lactones of the formula STR1 wherein A stands for --CH--CH2 X (X being Cl, Br or OH), --CHY--CHY-- (Y being Cl or Br), or STR2 and R1, R2 and R3 are the same or different radicals from the group of hydrogen and C1 to C10 alkyls, at least one of the radicals R1, R2 and R3 being such an alkyl radical, and process for making the same.
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