cas 5736-03-8, 2,2-Dimethyl-1,3-dioxolane-4-carboxaldehyde

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Preparation method of antitumor drug gemcitabine hydrochloride
The invention discloses a preparation method of an antitumor drug gemcitabine hydrochloride. The preparation method specifically comprises the following processes: (1) preparing an antitumor drug gemcitabine hydrochloride intermediate: Step 1, synthesis of T1; Step2, synthesis of T2; Step3, synthesis of T3; Step4, synthesis of T4; Step5, synthesis of T5; and Step6, synthesis of T6; and (2) preparing gemcitabine hydrochloride from the gemcitabine hydrochloride intermediate: Step7, firstly reducing T6 with lithium tri (tert-butoxy) aluminum hydride, and then acylating with paratoluensulfonyl chloride to prepare T7, wherein T7 is 2-deoxy-2, 2-difluoro-D-ribofuranose-3, 5-dibenzoate; and Step8, reacting T7 with cytosine under the action of a catalyst to generate T8, wherein T8 is 2'-deoxy-2',2'-difluorocytidine-D-ribofuranose-3',5'-dibenzoate. The preparation method of the antitumor drug gemcitabine hydrochloride has the advantages of low production cost, favorability for industrial production and small environmental pollution.
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Paragraph 0045; 0049; 0054-0055

(2020/12/31)

Chemoenzymatic Access to Chiral Tetrols Produced by Thiamine Diphosphate Dependent Benzaldehyde Lyase
Highly functionalized polyol building blocks have been synthesized by means of stereoselective chemoenzymatic C–C bond formation followed by stereoselective reduction. Catalysis by thiamine diphosphate (ThDP) dependent benzaldehyde lyase (BAL) with glyceraldehyde acetonide as acceptor substrate gave highly stereoenriched polyols such as (1S,2S,3R)-1-phenylbutane-1,2,3,4-tetrol (1), the 3,4-protected anti-1,2-diol 5, and the precursor of both compounds, 2-hydroxyketone 4.
Zecevic, Damir,Germer, Philipp,Walter, Lydia,Gauchenova, Ekaterina,Müller, Michael
p. 6465 - 6468
(2018/10/24)

Method for catalytic synthesis for glyceraldehyde acetonide
The invention relates to a method for catalytic synthesis for glyceraldehyde acetonide. The method specifically comprises the following steps: dissolving glycerol acetonide into acetone, adding a proper amount of a fullerene zinc oxide selenium (C60/ZnO/Se) composite material, introducing oxygen to carry out a reaction at a room temperature till a reaction liquid has no glycerol acetonide, centrifuging to remove the fullerene zinc oxide selenium (C60/ZnO/Se) composite material, carrying out vacuum concentration on supernate, and drying to obtain the glyceraldehyde acetonide.
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Paragraph 0056-0059

(2018/11/22)

A versatile route to polythiophenes with functional pendant groups using alkyne chemistry
A new versatile polythiophene building block, 3-(3,4-ethylenedioxythiophene)prop-1-yne (pyEDOT) (3), is prepared from glycidol in four steps in 28% overall yield. pyEDOT features an ethynyl group on its ethylenedioxy bridge, allowing further functionalization by alkyne chemistry. Its usefulness is demonstrated by a series of functionalized polythiophene derivatives that were obtained by pre- and post-electropolymerization transformations, provided by the synthetic ease of the Sonogashira coupling and click chemistry.
Huang, Xiao,Yang, Li,Emanuelsson, Rikard,Bergquist, Jonas,Str?mme, Maria,Sj?din, Martin,Gogoll, Adolf
supporting information
p. 2682 - 2688
(2017/01/09)

Synthesis of Cryptochiral (R,R)-2,3-Dideuterooxirane as Stereochemical Reference Compound and Chemical Correlation with D-(+)-Glyceraldehyde
Chirality plays a pivotal role in chemistry and biology, e.g., structure-specific targeting in drug development or the lock-and-key theory of enzyme interactions. Determining absolute configurations of chiral molecules is essential to understanding such mechanisms and to developing chemical processes involving chiral compounds. In particular, this becomes obvious in the understanding of chemical reaction networks in the context of the origins of life. A stereochemical reference compound that can be correlated with sugars, amino acids, etc. is of great interest. Here, we present the synthesis of enantiopure (R,R)-2,3-dideuterooxirane, of which the absolute configuration has been unambiguously determined by foil-induced Coulomb explosion imaging, and the correlation with the configuration of D-(+)-glyceraldehyde.
Trapp, Oliver,Zawatzky, Kerstin
p. 1082 - 1090
(2016/11/23)

Coulomb explosion imaged cryptochiral (R,R)-2,3-dideuterooxirane: Unambiguous access to the absolute configuration of (+)-glyceraldehyde
The absolute configuration of (R,R)-2,3-dideuterooxirane, which has been independently determined using Coulomb explosion imaging, has been unambiguously chemically correlated with the stereochemical key reference (+)-glyceraldehyde. This puts the absolute configuration of D(+)-glyceraldehyde on firm experimental grounds. 100% Absolute: The absolute configuration of (R,R)-2,3-dideuterooxirane, which has been independently determined by Coulomb explosion imaging (CEI), has been unambiguously chemically correlated with the stereochemical key reference (+)-glyceraldehyde. This puts the absolute configuration of D(+)-glyceraldehyde on firm experimental grounds (see scheme).
Zawatzky, Kerstin,Herwig, Philipp,Grieser, Manfred,Heber, Oded,Jordon-Thaden, Brandon,Krantz, Claude,Novotny, Oldrich,Repnow, Roland,Schurig, Volker,Schwalm, Dirk,Vager, Zeev,Wolf, Andreas,Kreckel, Holger,Trapp, Oliver
supporting information
p. 5555 - 5558
(2014/05/20)

Oxoammonium salt oxidations of alcohols in the presence of pyridine bases
Oxoammonium salt oxidations (using 4-acetylamino-2,2,6,6- tetramethylpiperidine-1-oxoammonium tetrafluoroborate) of alcohols containing a β-oxygen atom in the presence of pyridine yield dimeric esters, while in the presence of 2,6-lutidine the product is a simple aldehyde. The formation of a betaine between pyridine and an aldehyde is presented to explain this disparity in reactivity. The betaine is oxidized by the oxoammonium salt to give an N-acylpyridinium ion that serves as an acylating agent for ester formation. Steric effects deter the formation of such a betaine with 2,6-disubstituted pyridines. A series of alcohols containing a β-oxygen substituent were oxidized to aldehydes in the presence of 2,6-lutidine, and a short study of the relative reactivity of various alcohols is given. An overall mechanism for oxoammonium cation oxidations is suggested, premised on nucleophilic additions to the oxygen atom of the positively charged nitrogen-oxygen double bond. Possible mechanisms for both dimeric oxidations and simple oxidations are given.
Bobbitt, James M.,Bartelson, Ashley L.,Bailey, William F.,Hamlin, Trevor A.,Kelly, Christopher B.
p. 1055 - 1067
(2014/03/21)

Access to functionalized steroid side chains via modified Julia olefination
Various functionalized steroidal side chains were conveniently accessed by a modified Julia olefination strategy using a common sulfone donor and an appropriate α-branched aldehyde acceptor. For the coupling of these hindered classes of reaction partners (and in contrast to typically observed trends), the benzothiazolyl(BT)-sulfone anion gave superior outcomes compared to the phenyltetrazolyl(PT)-sulfone anion.
Izgu, Enver Cagri,Burns, Aaron C.,Hoye, Thomas R.
supporting information; scheme or table
p. 703 - 705
(2011/04/26)

SUBSTITUTED BENZOAZEPINES AS TOLL-LIKE RECEPTOR MODULATORS
Provided are compositions and methods useful for modulation of signaling through the Toll- like receptors TLR7 and/or TLR8. The compositions and methods have use in treating or preventing disease, including cancer, autoimmune disease, infectious disease, inflammatory disorder, graft rejection, and graft-verses-host disease.
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Page/Page column 68

(2011/04/13)

Stereoselective triplet-sensitised radical reactions of furanone derivatives
The stereo- and regioselectivity of triplet-sensitised radical reactions of furanone derivatives have been investigated. Furanones 7a,b were excited to the 3ππ* state by triplet energy transfer from acetone. Intramolecular hydrogen abstraction then occurred such that hydrogen was transferred from the tetrahydropyran to the β position of the furanone moiety. Radical combination of the tetrahydropyranyl and the oxoallyl radicals led to the final products 8a,b. In the intramolecular reaction, overall, a pyranyl group adds to the a position of the furanone. The effect of conformation was first investigated with compounds 9a,b carrying an additional substituent on the tether between the furanone and pyranyl moiety. Further information on the effect of conformation and the relative configuration at the pyranyl anomeric centre and the furanone moiety was obtained from the transformations of the glucose derivatives 12, 14, 17 and 18. Radical abstraction occurred at the anomeric centre and at the S′-position of the glucosyl moiety. Computational studies of the hydrogen-abstraction step were carried out with model structures. The activation barriers of this step for different stereoisomers and the abstraction at the anomeric centre and at the 6' -position of the tetrahydropyranyl moiety were calculated. The results of this investigation are in accordance with experimental observations. Furthermore, they reveal that the reactivity and regioselectivity are mainly determined in the hydrogen-abstraction step. Intramolecular hydrogen abstraction (almost simultaneous electron and proton transfer) in 3ππ * excited furanones only takes place under restricted structural conditions in a limited number of conformations that are defined by the relative configuration of the substrates. It is observed that in the biradical intermediate, back-hydrogen transfer occurs leading to the starting compound. In the case of glucose derivatives, this reaction led to epimerisation at the anomeric centre.
Jahjah, Rabih,Gassama, Abdoulaye,Bulach, Veronique,Suzuki, Chikako,Abe, Manabu,Hoffmann, Norbert,Martinez, Agathe,Nuzillard, Jean-Marc
supporting information; scheme or table
p. 3341 - 3354
(2010/06/19)

USE OF 4-AMINO-PIPERIDINES FOR TREATING SLEEP DISORDERS
Inverse agonists and antagonists of serotonin receptors are disclosed for use in treating sleep disorders such as insomnia, and specifically sleep maintenance insomnia. The compound increase slow wave sleep, decrease the number of awakenings after sleep onset, and decrease the time awake after sleep onset.
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Page/Page column 170

(2010/11/28)

Engineering stereocontrol into an aldolase-catalysed reaction
A novel thermostable aldolase has been developed for synthetic application, and substrate engineering has been used to induce stereocontrol into aldol reactions of this naturally-promiscuous enzyme.
Lamble, Henry J.,Danson, Michael J.,Hough, David W.,Bull, Steven D.
p. 124 - 126
(2007/10/03)

PROCESS FOR THE PREPARATION OF GLYCERALDEHYDE ACETONIDE
The invention relates to a process for the preparation of glyceraldehyde acetonide by oxidation of 2,2-dimethyl-1,3-dioxolane-4-methanol by an oxidizing agent, wherein the 2,2-dimethyl-1,3-dioxolane-4-methanol is oxidized by an organic N-chloro compound in the presence of an inert base and TEMPO or a TEMPO-derivative. In one embodiment of the invention enantiomerically enriched glyceraldehyde acetonide is prepared from the corresponding enantiomerically enriched 2,2-dimethyl-1,3-dioxolane-4-methanol. Preferably, the organic N-chloro compount is trichloroisocyanuric acid or dichlorodimethyl hydantoin. Preferably, the inert base is sodium acetate or sodium bicarbonate.
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Page/Page column 10-11

(2008/06/13)

Pd-catalyzed nucleophilic allylic alkylation of aliphatic aldehydes by the use of allyl alcohols
Under catalysis of Pd(OAc)2-(P-n-Bu)3, Et 2Zn promotes a variety of allyl alcohols to undergo nucleophilic allylation of aliphatic aldehydes and ketones at room temperature and provides homoallyl alcohols in 60-90 and ca. 60% isolated yield, respectively. The reaction is irreversible and kinetically controlled, and unique regio- and stereoselectivities observed for the allylation with unsymmetrically substituted allyl alcohols are discussed.
Kimura, Masanari,Shimizu, Masamichi,Tanaka, Shuji,Tamaru, Yoshinao
p. 3709 - 3718
(2007/10/03)

Technical production of aldehydes by continuous bleach oxidation of alcohols catalyzed by 4-hydroxy-TEMPO
Aldehydes can be easily prepared from the corresponding alcohols in good to excellent yields by oxidation with technical bleach and catalytic amounts of 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (1b, 4-hydroxy TEMPO, "HOT"). Whereas the well-known batch process performed on lab scale is not suitable for the technical synthesis especially of activated β-substituted aldehydes, this transformation can be performed continuously in a simple tube reactor. This layout meets all requirements necessary for the process, i.e., turbulent mixing of the biphasic mixture, removal of heat, short contact times, and high output. Thus, a single tube of 3 mm diameter renders about 60 mol of aldehyde per day.
Fritz-Langhals, Elke
p. 577 - 582
(2012/12/25)

Hemisynthesis of methyl pyrethroates from γ-alkoxy-alkylidene malonates and isopropylidenediphenylsulfurane and isopropylidenetriphenylphosphorane
Hemisynthesis of methyl pyrethroates from γ-alkoxy-alkylidene malonates and isopropylidenediphenylsulfurane and isopropylidenetriphenylphosphorane is disclosed. It takes advantage of the high degree of stereocontrol observed in the cyclopropanation of γ-alkoxy- alkylidene malonates by the above mentioned ylides.
Krief, Alain,Froidbise, Alexandre
p. 7637 - 7658
(2007/10/03)

Stereocontrolled synthesis of novel 6′(α)-hydroxy carbovir analogues
This paper describes the racemic and stereoselective synthetic route for a novel 6′(α)-hydroxy-carbovir from a simple acyclic precursor, Solketal. The relative stereochemistry of the target nucleosides was successfully controlled by a sequential stereoselective glycolate Claisen rearrangement followed by a ring-closing metathesis (RCM). Adenine and cytosine were coupled using a Pd(0) catalyzed allylic alkylation strategy in a high regio- and stereoselective manner.
Hong, Joon Hee,Oh, Chang-Hyun,Cho, Jung-Hyuck
p. 6103 - 6108
(2007/10/03)

Catalyst-controlled diastereoselective hetero-Diels-Alder reactions
The diastereoselective hetero-Diels-Alder reaction between Danishefsky's diene and chiral aldehydes is catalyzed by chiral chromium-Schiff base complexes. High levels of catalyst control are obtained in several cases, allowing access to all four stereoisomeric products through appropriate choice of aldehyde and catalyst enantiomers.
Joly, Guy D.,Jacobsen, Eric N.
p. 1795 - 1798
(2007/10/03)

Julia-Colonna stereoselective epoxidation of some α,β-unsaturated enones possessing a stereogenic centre at the γ-position: Synthesis of a protected galactonic acid derivative
The oxidation of enones 6-8 using peroxide or percarbonate and polyleucines as catalysts gave the corresponding diastereomers 9-12 in high yield. The compound 9 was converted into the galactonic acid derivative 16 in five steps and in an overall yield of nearly 60%. Polyleucines are shown to be catalysts powerful enough to overturn the intrinsic stereocontrol in the chosen substrates.
Ray, Peter C.,Roberts, Stanley M.
p. 149 - 153
(2007/10/03)

Diastereoselective synthesis of dimethyl cyclopropane-1,1-dicarboxylates from a γ-alkoxy-alkylidene malonate and sulfur and phosphorus ylides
Isopropylidene diphenylsulfurane and isopropylidene triphenylphosphorane react by the same (Re) face of the alkylidene malonate derived from the acetonide of (d)-glyceraldehyde to produce almost exclusively a single diastereoisomer of the corresponding dimethyl cyclopropane-1,1-dicarboxylate.
Krief, Alain,Provins, Laurent,Froidbise, Alexandre
p. 1437 - 1440
(2007/10/03)

Photochemistry of 1-Alkoxy- and 1-(Benzyloxy)-9,10-anthraquinones in Methanol: A Facile Process for the Preparation of Aldehydes and Ketones
The facile production of acid sensitive aldehydes and ketones via photochemical intramolecular δ-hydrogen atom transfer in 1-alkoxy- and 1-(benzyloxy)-9,10-anthraquinones (1) was investigated.Irradiation of 1 in argon purged methanol generates the primary photoproducts, 1-(RCH(OMe)O)- and 1-(ArCH(OMe)O)-9,10-anthrahydroquinones (2), respectively.Upon exposure to air, the intermediate anthrahydroquinone is rapidly converted to the corresponding aldehyde and 1-hydroxy-9,10-anthraquinone (3), which can be recycled.Aldehydes containing an acetal or ketal were prepared in high yields using this photoprocess.Apparent rate constants for the photodemethylation of 1-methoxy-2-X-9,10-anthraquinones (X = H, Me, Et, Pr, i-Bu, and benzyl) were measured and found to vary by a factor of 10 separating the slowest anthraquinone (X = H) and the fastest (X = benzyl), indicating a strong dependency upon the size of the substituent at the 2-position.These rate constants are ascribed to equilibrium populations of conformers in the geometry required for the reaction in the n,?* triplet state.
Blankespoor, Ronald L.,Smart, Robert P.,Batts, Eric D.,Kiste, Alan A.,Lew, Rebecca E.,Vliet, Marc E. Vander
p. 6852 - 6859
(2007/10/03)

Free-Radical Chemistry of Imines
Aryl radicals bearing an aldimino functional group as part of an ortho substituent cyclized by addition to C and/or N of the imino group.When the choice was between 5-exo closure to C and 6-endo closure to N, the former predominated.However, 6-endo closure to C predominated over 5-exo cyclization to N in isomeric imines.Absolute values of cyclization rate constants were determined and an explanation for the unusual 6-endo preference is offered.Chiral induction in 6-endo cyclization to C of an aldimine from D-glyceraldehyde acetonide was observed, and its sense was determined.
Tomaszewski, Miroslaw J.,Warkentin, John,Werstiuk, Nick H.
p. 291 - 322
(2007/10/02)

An azido-functionalized isocarbacyclin analogue acting as an efficient photoaffinity probe for a prostacyclin receptor
A stable prostacyclin analogue, (15S)-18c, having an azidophenyl group as a photoaffinity labeling functionality has been synthesized. This compound has a sufficiently high affinity to the prostacyclin receptor protein in mastocytoma P-815 cells, exhibiting an IC50 value of 3 nM for the replacement of iloprost bound to the receptor protein. A photoaffinity probe compound, [3H]-(15S)-18c, is obtainable by reduction of the ketone 16c with [3H]NaBH4 - CeCl3 followed by alkaline hydrolysis of the methyl ester.
Suzuki, Masaaki,Koyano, Hiroshi,Noyori, Ryoji,Hashimoto, Hitoshi,Negishi, Manabu,Ichikawa, Atsushi,Ito, Seiji
p. 2635 - 2658
(2007/10/02)

Dihydropyridines chirales modeles de NADH: preparation d'esters de Hantzsch substitues par des monosaccharides
The 1,4-dihydropyridine ring of Hantzsch esters (HEH) was chosen as NADH models to perform chemical reductions; chiral HEH were prepared for the sake of asymmetric reductions and, for that purpose, sugar substituents were introduced on the 4- or both 3- and 5- position of the HEH ring by means of a one pot cyclisation reaction using suitable monosaccharides derivatives.
Zehani, Sadek,Llauro, Marie-France,Gelbard, Georges
p. 104 - 113
(2007/10/02)

A New and Efficient Heterogeneous System for the Oxidative Cleavage of 1,2-Diols and the Oxidation of Hydroquinones
Sodium periodate/wet silica gel in the presence of dichloromethane is an efficient reagent for the oxidative cleavage of 1,2-diols and the oxidation of hydroquinones.This easily prepared reagent provides a good alternative of classical metaperiodate oxidation, especially for the preparation of aldehydes, which easily form hydrates.
Daumas, M.,Vo-Quang, Y.,Vo-Quang, L.,Goffic, F. Le
p. 64 - 65
(2007/10/02)

Potential inhibitors of S-adenosylmethionine-dependent methyltransferases. 11. Molecular dissections of neplanocin A as potential inhibitors of S-adenosylhomocysteine hydrolase
A series of 9-(hydroxyalkenyl)purines (adenines and 3-deazaadenines), which are analogues of neplanocin A, were synthesized. The analogues were tested as inhibitors of bovine liver and murine L929 cell S-adenosylhomocysteine (AdoHcy) hydrolase (EC 3.3.1.1) and as inhibitors of vaccinia virus replication in murine L929 cells. Compounds 1b, 2a, 2b, 4a, 4b, 7, 9a, and 9b showed the best inhibitory effects toward bovine liver AdoHcy hydrolase, with compound 4b being the most potent. The compounds that were shown to be the most potent inhibitors of the bovine liver AdoHcy hydrolase all contained an allylic hydroxyl group in the cis position to the adenine or the 3-deazaadenine rings. It was concluded that the cis arrangement of the allylic hydroxyl groups in these acyclic compounds represented the minimum structural requirement of the trihydroxycyclopentenyl ring of neplanocin A to show inhibitory effects against AdoHcy hydrolase. The antiviral effects of these acyclic analogues were significantly less than neplanocin A; however, there appears to be a correlation between the antiviral activity and the inhibition of AdoHcy hydrolase for compounds 2a, 2b, 4a, 4b, and 7. Analogue 4b, which exhibited the best antiviral activity (IC50=70 μM) in this acyclic series, is substantially less potent than neplanocin A (IC50=0.08 μM) as an antiviral agent.
Borcherding,Narayanan,Hasobe,McKee,Keller,Borchardt
p. 1729 - 1738
(2007/10/02)

A USEFUL PREPARATION OF L-(S)-GLYCERALDEHYDE ACETONIDE
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Huss, Keith E. Maloney
p. 273 - 278
(2007/10/02)

Chiral Buildung Units from Carbohydrates, IX. - Synthesis of Enantiomeric 2,8-Dimethyl-1,7-dioxaspiroundecan-4-ols, Components from the Pheromone Bouquet of Andrena wilkella
The enantiomeric spiro acetals 29 and 35 are synthesized via the open-chained compounds 27 and 33 which are obtained by connecting the open-chained, D- or L-threo configurated, blocked trideoxytrimethylene dithioacetals IV with 1-iodo-4-(tetrahydropyranoloxy)pentane (1).One of the two enantiomers 29 or 35 represents a component from the pheromone bouquet of Andrena wilkella.The synthesis of racemic 1 is described as well as the synthesis of 1 in optically pure form in two different, independent ways, starting from D-glyceraldehyde and D-glucose.
Redlich, Hartmut,Schneider, Bernd
p. 412 - 424
(2007/10/02)

Acyclic Stereoselection. 12. Double Stereodifferentiation with Mutual Kinetic Resolution. A Superior Class of Reagents for Control of Cram's Rule Stereoselection in Synthesis of erythro-α-Alkyl-β-hydroxy Carboxylic Acids from Chiral Aldehydes
Chiral α- ketones 7-9 have been prepared and their aldol condesations studied.Compound 8 shows from good to excellent inherent diastereoface selectivity in reactions with achiral aldehydes.Stereoselectivity is related to the size of the alkyl group attached to the aldehyde carbonyl; highest selectivity is observed with diphenylacetaldehyde (>10:1) and pivaldehyde (>19:1).Ketone 8 also shows high diastereoface selectivity in its reactions with chiral, racemic aldehydes 21, 25, 29, and 17, only one stereoisomeric aldol being obtained in each case.Furthermore, the four aforementioned aldehydes show much higher diastereoface selectivity with ketone 8 than they do with the related ketone 1.As a result, the reactions of racemic 8 with these chiral, racemic aldehydes show a high degree of "mutual kinetic resolution".In fact, the rate of the (R)-enolate plus (R)-aldehyde condensation is at least 35 times the rate of the (R)-enolate plus (S)-aldehyde condensation.It is shown by simple logical argument that such mutual kinetic resolution is expected in reactions between two chiral racemic compounds and that the magnitude of the effect should be proportional to the inherent diastereoselectivity shown by each compound in its reaction with achiral reaction partners.Thus, reagents such as 8 can be used to obtain the benefits of double stereodifferentiation even in the racemic form.As an application of the chemistry developed, (+/-)-blastmycinone (47) has been prepared in four steps from ketone 9 (20percent overall yield).
Heathcock, Clayton H.,Pirrung, Michael C.,Lampe, John,Buse, Charles T.,Young, Steven D.
p. 2290 - 2300
(2007/10/02)