- Stereoselective Palladium-Catalyzed Arylation of Exo-Glycals with Aryl Iodides
-
A novel methodology for the arylation of exo-glycals has been developed. A range of exo-glycals underwent reactions with aryl iodides in the presence of a palladium catalyst. The transformation proceeded in a stereoselective manner to afford Z-isomers. Th
- Regier, Jeffery,Ghanty, Supriya,Bolshan, Yuri
-
supporting information
p. 524 - 530
(2022/01/12)
-
- Weinreb Amide Approach to the Practical Synthesis of a Key Remdesivir Intermediate
-
Currently, remdesivir is the first and only FDA-approved antiviral drug for COVID-19 treatment. Adequate supplies of remdesivir are highly warranted to cope with this global public health crisis. Herein, we report a Weinreb amide approach for preparing the key intermediate of remdesivir in the glycosylation step where overaddition side reactions are eliminated. Starting from 2,3,5-tri-O-benzyl-d-ribonolactone, the preferred route consisting of three sequential steps (Weinreb amidation, O-TMS protection, and Grignard addition) enables a high-yield (65%) synthesis of this intermediate at a kilogram scale. In particular, the undesirable PhMgCl used in previous methods was successfully replaced by MeMgBr. This approach proved to be suitable for the scalable production of the key remdesivir intermediate.
- Xie, Yuanchao,Hu, Tianwen,Zhang, Yan,Wei, Daibao,Zheng, Wei,Zhu, Fuqiang,Tian, Guanghui,Aisa, Haji A.,Shen, Jingshan
-
p. 5065 - 5072
(2021/04/12)
-
- Synthesis and evaluation of a collection of purine-like C-nucleosides as antikinetoplastid agents
-
The kinetoplastid parasites Trypanosoma brucei, Trypanosoma cruzi and Leishmania spp. are the causative agents of neglected tropical diseases with a serious burden in several parts of the world. These parasites are incapable of synthesizing purines de nov
- Bouton, Jakob,Maes, Louis,Karalic, Izet,Caljon, Guy,Van Calenbergh, Serge
-
-
- Compound for treating viral infection and preparation method and application of compound
-
The invention provides a preparation for treating viral infection and pneumovirus subfamily viral infection, a method, a compound as shown in a formula (I) and a method and intermediate for synthesis of the compound as shown in the formula (I).
- -
-
Paragraph 0149-0154
(2021/08/07)
-
- Compound containing guanidyl group, and preparation method and application thereof
-
The invention provides a preparation containing a guanidino compound and used for treating pneumoviridae virus infection, a method, a compound of a formula I, and a method and an intermediate for synthesizing the compound of the formula I.
- -
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Paragraph 0138-0143
(2021/08/07)
-
- Novel compound and application thereof
-
The invention relates to a novel compound and application thereof, and also relates to an application of the compound in preparation of antiviral drugs and the like. In particular, AIDS virus is present. Application of hepatitis B virus, paramyxovirus and
- -
-
Paragraph 0081-0083
(2021/09/08)
-
- ISOMORPHS OF REMDESIVIR AND METHODS FOR SYNTHESIS OF SAME
-
A new isoform of 2-ethylbutyl (2S)-2-[[[(2R,3S,4R,5R)-5-(4-aminopyrrolo[2,1-f][1,2,4]triazin-7-yl)-5-cyano-3/4-dihydroxyoxolan-2-yl]methoxy-phenoxyphosphoryl]amino]propanoate (Remdesivir) having increased water solubility is disclosed, along with methods
- -
-
Paragraph 0083
(2021/06/04)
-
- ANTIVIRAL NUCLEOSIDES AND DERIVATIVES THEREOF
-
Disclosed herein are nucleoside compounds and derivatives thereof, pharmaceutical compositions containing same, and their methods of synthesis. The compounds are useful in treating orthomyxovirus infections, such as influenza infections.
- -
-
-
- Synthesis of remdesivir key intermediate 2, 3, 5-tribenzyloxy-D-ribotide-1, 4-lactone
-
The invention relates to synthesis of a remdesivir key intermediate 2, 3, 5-tribenzyloxy-D-ribotide-1, 4-lactone. The invention discloses a synthesis method of 2, 3, 5-tribenzyloxy-D-ribotide-1, 4-lactone, and belongs to the field of organic synthesis. The method includes: taking D-ribose as an initial raw material, in methanol, using concentrated sulfuric acid as a catalyst, synthesizing a methoxy compound 2, then fully stirring the substances in a saturated sodium hydroxide solution, adding tetrahydrofuran and n-butylammonium hydrogen sulfate, and then adding benzyl bromide to synthesize a compound 3, dissolving the compound 3 in tetrahydrofuran and then performing catalysis with concentrated sulfuric acid, and performing reflux stirring overnight treatment to obtain a compound 4, dissolving the compound 4 into dichloromethane and water, adding sodium bicarbonate and TEMPO, slowly adding sodium hypochlorite at 0DEG C, raising the temperature to room temperature, and conducting stirring overnight treatment to obtain a compound 5. The method has the characteristics of easily available raw materials and low production cost, each process step is simple and easy to treat, the yield ofthe whole route reaches 43% or above, industrial production is easy to realize, and a basis is provided for industrialization of remdesivir and subsequent derivatives thereof.
- -
-
-
- Method for preparing 2, 3, 5 -tribenzyloxy - D D-ribose -1, 4 - lactone in continuous flow microchannel reactor (by machine translation)
-
The method disclosed by the invention has the advantages of simple operation, safety, 3 short 5 - reaction time,1 high 4 - product conversion rate, high product purity and the like 2, 3 and 5 - has the advantages of simple operation, 2 safety 3, 5 - short
- -
-
Paragraph 0040-0081
(2020/09/02)
-
- Preparation method of 2, 3, 5-tribenzyloxy-D-ribose-1, 4-lactone
-
The invention provides a preparation method of 2, 3, 5-tribenzyloxy-D-ribose-1, 4-lactone. In the preparation method, in the oxidation step, sodium bromide/TEMPO is creatively used as a catalyst, sodium hypochlorite serves as an oxidizing agent, a large a
- -
-
Paragraph 0030-0064
(2020/07/02)
-
- Efficient and regioselective synthesis of γ-lactone glycosides through a novel debenzylative cyclization reaction
-
An efficient and regioselective approach for the construction of synthetically important γ-lactone glycosides is reported from unprotected aldoses through a new debenzylative lactonization (DBL) reaction. The scope and limitations of this DBL reaction are described starting from a series of commercially available hexoses (l-fucose, d-galactose, d-glucose) and pentoses (d-arabinose, d-ribose, d-lyxose, d-xylose) to afford the corresponding γ-lactones in good yields and without concomitant δ-lactone formation.
- Delbrouck, Julien A.,Tikad, Abdellatif,Vincent, Stéphane P.
-
supporting information
p. 9845 - 9848
(2018/09/10)
-
- Synthetic process for benzyl ribose lactone
-
The invention discloses a synthetic process for benzyl ribose lactone, relates to the technical field of medicine synthesis, and solves the technical problems that crystal purification steps in an existing process are complex, and reaction still locking can appear. According to the process, different reagent and solvent are selected, intermediate does not undergo the purification treatment and directly gets into the next step with an oily matter or without further concentration treatment, the intermediate undergoes separation and purification and crystallization at the final step, the processhas the advantages that the purification and crystallization steps are simple, and the problem of the reaction still locking can not appear, the loss is reduced, the yield coefficient reaches to 79%,and the purity reaches to 99% or above; According to the process, the expensive solvent is replaced by the cheap reagent, under the circumstance of not affecting the product quality and yield coefficient, the synthesis cost of the benzyl ribose lactone is reduced.
- -
-
-
- Synthesis and Biological Evaluation of Pyrrolo[2,1-f][1,2,4]triazine C-Nucleosides with a Ribose, 2′-Deoxyribose, and 2′,3′-Dideoxyribose Sugar Moiety
-
The synthesis of hitherto unknown pyrrolo[2,1-f][1,2,4]triazine C-nucleosides is described. Structural variations (chlorine, bromine, iodine, and cyano groups) were introduced at position 7 of 4-aza-7,9-dideazaadenine. In addition, pyrrolo[2,1-f][1,2,4]triazine C-nucleosides bearing a 2′-deoxy-, 2′,3′-dideoxy-, and 2′,3′-dehydrodideoxyribose moiety were also prepared. Among these analogues, the pyrrolo[2,1-f][1,2,4]triazine C-ribonucleosides with either a hydrogen atom or cyano group at position 7 of the nucleobase displayed potent cytotoxic activity in a panel of various cancer cell lines.
- Li, Qingfeng,Lescrinier, Eveline,Groaz, Elisabetta,Persoons, Leentje,Daelemans, Dirk,Herdewijn, Piet,De Jonghe, Steven
-
-
- METHODS FOR TREATING ARENAVIRIDAE AND CORONAVIRIDAE VIRUS INFECTIONS
-
Provided are methods for treating Arenaviridae and Coronaviridae virus infections by administering nucleosides and prodrugs thereof, of Formula I: wherein the 1′ position of the nucleoside sugar is substituted. The compounds, compositions, and methods provided are particularly useful for the treatment of Lassa virus and Junin virus infections.
- -
-
Paragraph 0517-0518
(2017/04/04)
-
- METHODS FOR TREATING FLAVIVIRIDAE VIRUS INFECTIONS
-
Provided are methods for treating Flaviviridae virus infections by administering ribosides, riboside phosphates and prodrugs thereof, of Formula I:, wherein the 1' position of the nucleoside sugar is substituted. The compounds, compositions, and methods provided are particularly useful for the treatment of Zika virus infections.
- -
-
Paragraph 0256
(2017/11/15)
-
- Synthesis of Unprecedented Sulfonylated Phosphono-exo-Glycals Designed as Inhibitors of the Three Mycobacterial Galactofuranose Processing Enzymes
-
This study reports a new methodology to synthesize exo-glycals bearing both a sulfone and a phosphonate. This synthetic strategy provides a way to generate exo-glycals displaying two electron-withdrawing groups and was applied to eight different carbohydrates from the furanose and pyranose series. The Z/E configurations of these tetrasubstituted enol ethers could be ascertained using NMR spectroscopic techniques. Deprotection of an exo-glycal followed by an UMP (uridine monophosphate) coupling generated two new UDP (uridine diphosphate)-galactofuranose analogues. These two Z/E isomers were evaluated as inhibitors of UGM, GlfT1, and GlfT2, the three mycobacterial galactofuranose processing enzymes. Molecule 46-(E) is the first characterized inhibitor of GlfT1 reported to date and was also found to efficiently inhibit UGM in a reversible manner. Interestingly, GlfT2 showed a better affinity for the (Z) isomer. The three enzymes studied in the present work are not only interesting because, mechanistically, they are still the topic of intense investigations, but also because they constitute very important targets for the development of novel antimycobacterial agents.
- Frédéric, Christophe J.-M.,Tikad, Abdellatif,Fu, Jian,Pan, Weidong,Zheng, Ruixiang B.,Koizumi, Akihiko,Xue, Xiaochao,Lowary, Todd L.,Vincent, Stéphane P.
-
p. 15913 - 15920
(2016/10/25)
-
- METHODS FOR TREATING FILOVIRIDAE VIRUS INFECTIONS
-
Provided are compounds, methods, and pharmaceutical compositions for treating Filoviridae vims infections by administering ribosides, riboside phosphates and prodrugs thereof, of Formula (IV): The compounds, compositions, and methods provided are particularly useful for the treatment of Marburg virus, Ebola virus and Cueva virus infections.
- -
-
Paragraph 0181
(2016/05/19)
-
- Stereoselectivity in the Lewis acid mediated reduction of ketofuranoses
-
The Lewis acid mediated reduction of ribose-, arabinose-, xylose-, and lyxose-derived methyl and phenyl ketofuranoses with triethylsilane as nucleophile was found to proceed with good to excellent stereoselectivity to provide the 1,2-cis addition products
- Van Rijssel, Erwin R.,Van Delft, Pieter,Van Marle, Daan V.,Bijvoets, Stefan M.,Lodder, Gerrit,Overkleeft, Herman S.,Van Der Marel, Gijsbert A.,Filippov, Dmitri V.,Codée, Jeroen D.C.
-
p. 4553 - 4565
(2015/05/13)
-
- Synthesis of C-spiro-glycoconjugates from sugar lactones via zinc mediated Barbier reaction
-
Anomeric gem-diallylation, mono-β-crotylation and mono-β- propargylation of sugar 1,5 and 1,4 lactones have been achieved under Barbier reaction conditions using Zn powder and a catalytic amount of TMSCl as an activator. Ring closing olefin metathesis of the synthesized gem-diallyl derivatives furnished C-spiro cyclopentene glycosides. Finally, the cyclopentene rings were converted into carbohydrate based tricyclic morpholine fused triazole glycoconjugates as potential SGLT2 inhibitors.
- Lambu, Mallikharjuna Rao,Hussain, Altaf,Sharma, Deepak K.,Yousuf, Syed Khalid,Singh, Baldev,Tripathi, Anil. K.,Mukherjee, Debaraj
-
p. 11023 - 11028
(2014/03/21)
-
- Sugar-derived cyclic imines: One-pot synthesis and direct functionalization
-
A simple method for the synthesis of sugar-derived imines by a Schwartz's reagent reduction of easily available sugar lactams has been described. A direct addition of nucleophiles to the generated in situ cyclic imines and subsequent deprotection of hydroxyl function allows to convert sugar lactams in polyhydroxylated pyrrolidines and piperidines.
- Szcze?niak, Piotr,Stecko, Sebastian,Staszewska-Krajewska, Olga,Furman, Bart?omiej
-
p. 1880 - 1888
(2014/03/21)
-
- Synthesis of polyhydroxylated quinolizidine and indolizidine scaffolds from sugar-derived lactams via a one-pot reduction/Mannich/Michael sequence
-
A direct approach to the synthesis of indolizidine and quinolizidine scaffolds of iminosugars is described. The presented strategy is based on a one-pot sugar lactam reduction with Schwartz's reagent followed by a diastereoselective Mannich/Michael tandem reaction of the resulting sugar imine with Danishefsky's diene. The stereochemical course of the investigated reaction has been explained in detail. The obtained bicyclic products are attractive building blocks for the synthesis of various naturally occurring polyhydroxylated alkaloids and their derivatives.
- Szczesniak, Piotr,Stecko, Sebastian,Maziarz, Elzbieta,Staszewska-Krajewska, Olga,Furman, Bartlomiej
-
p. 10487 - 10503
(2015/02/19)
-
- METHODS AND COMPOUNDS FOR TREATING PARAMYXOVIRIDAE VIRUS INFECTIONS
-
Provided are methods for treating Paramyxoviridae virus infections by administering ribosides, riboside phosphates and prodrugs thereof, of Formula (I): wherein the 1 ? position of the nucleoside sugar is substituted. The compounds, compositions, and methods provided are particularly useful for the treatment of Human parainfluenza and Human respiratory syncytial virus infections
- -
-
Page/Page column 109
(2012/02/05)
-
- PROCESSES AND INTERMEDIATES FOR THE PREPARATION OF 1'-SUBSTITUTED CARBA-NUCLEOSIDE ANALOGS
-
Provided are processes and intermediates for the syntheses of nucleosides of pyrrolo[1,2-f][1,2,4]triazinyl and imidazo[1,2-f][1,2,4]triazinyl heterocycles of Formula I.
- -
-
Page/Page column 70-71
(2011/04/19)
-
- CARBA-NUCLEOSIDE ANALOGS FOR ANTIVIRAL TREATMENT
-
Provided are thieno[3,4-d]pyrimidin-7-yI and furo[3,4-d]pyrimidin-7-yl ribosides, riboside phosphates and prodrugs thereof as well as intermediates and methods of preparation. The compounds, compositions, and methods provided are useful for the treatment of Flaviviridae virus infections.
- -
-
Page/Page column 158
(2010/09/03)
-
- Synthesis of differently protected 1-C-methyl-ribofuranoses intermediates for the preparation of biologically active 1'-C-methyl-ribonucleosides
-
Starting from D-ribose, differently protected 1-C-methyl-D-ribofuranoses have been prepared as intermediates for the synthesis of variously modified 1'-C-methyl-ribonucleosides, a class of compounds potentially endowed with interesting biological activity.
- Alessandrini, Laura,Casati, Silvana,Ciuffreda, Pierangela,Ottria, Roberta,Santaniello, Enzo
-
p. 332 - 344
(2008/12/21)
-
- NEW SALT OF (2R,3R,4R)-3,4-DIHYDROXY-2-HYDROXYMETHYLPYRROLIDINE
-
This invention relates to (2R,3R,4R)-3,4-dihydroxy-2-hydroxymethylpyrrolidine, 2-naphthalenesulfonate, preparation thereof and use as therapeutic agent.
- -
-
Page/Page column 8
(2008/06/13)
-
- Stereoselective synthesis of a ketohexofuranose from an aldohexopyranose by a [6+1-1] strategy
-
Ozonolysis of 2-acetoxymethyl-1,5-anhydro-3,4,6-tri-O-benzyl-2-deoxy-D- arabino-hex-1-enitol gave 1-O-acetyl-3,4,6-tri-O-benzyl-4-O-formyl-D-arabino- hex-2-ulose (5). Subsequent hydrolysis and acetylation of 5 provided 1,2-di-O-acetyl-3,4,6-tri-O-benzyl-D
- Babu, Boga Sobhana,Balasubramanian, Kalpattu Kuppuswamy
-
p. 753 - 758
(2007/10/03)
-
- Palladium-catalyzed oxidation of benzylated aldose hemiacetals to lactones
-
Benzyl protected sugar hemiacetals are oxidized to the corresponding lactones in excellent yields using bromobenzene, K2CO3 and the Pd(OAc)2/PPh3 catalytic system.
- Bessmertnykh, Alla,Henin, Francoise,Muzart, Jacques
-
p. 1377 - 1380
(2007/10/03)
-
- Glycosylidene carbenes: Part 31. Glycosylidene diaziridines: Stereoselective addition of ammonia and methylamine to lactone oxime sulfonates
-
The diastereoselectivity of the addition of NH3 and MeNH2 to glyconolactone oxime sulfonates and the structures of the resulting N-unsubstituted and N-methylated glycosylidene diaziridines were The 15N-labelled glucono- and galactono-1,5-lactone oxime mesylates 1* and 9* add NH3 mostly axially (> 3:1; Scheme 4), while the 15N-labelled mannono-1,5-lactone oxime sulfonate 19* adds NH3 mostly equatorially (9:1; Scheme 7). The 15N-labelled mannono-1,4-lactone oxime sulfonate 30* adds NH3 mostly from the exo side (>4:1; Scheme 9). The configuration of the N-methylated pyranosylidene diaziridines 17, 18, 28, and 29 suggests that MeNH2 adds to 1, 9, 19, and 23 mostly to exclusively from the equatorial direction (> 7:3; Schemes 5 and 8). The mannono-1,4-lactone oxime sulfonate 30 adds MeNH2 mostly from the exo side (85:15; Scheme 10), while the ribo analogue 37 adds MeNH2 mostly from the endo side (4:1; Scheme 10). Analysis of the preferred and of the reactive conformers of the tetrahedral intermediates suggests that the addition of the amine to lactone oxime sulfonates is kinetically controlled. The diastereoselectivity of the diaziridine formation is rationalized as the result of the competing influences of intramolecular H-bonding during addition of the amines, steric interactions (addition of MeNH2), and the kinetic anomeric effect. The diaziridines obtained from 2,3,5-tri-O-benzyI-D-ribono- and -D-arabinono-1,4-lactone oxime methanesulfonate (42 and 48; Scheme II) decomposed readily to mixtures of 1,4-dihydro-1,2,4,5-tetrazines, pentono-1,4-lactones, and pentonamides. The N-unsubstituted gluco- and galactopyranosylidene diaziridines 2, 4, 6, 8, and 10 are mixtures of two trans-substituted isomers (S/R ca. 19:1, Scheme 2). The main, (S,S)-configured isomers S are stabilised by a weak intramolecular H-bond from the pseudoaxial NH to RO-C(2). The diaziridines 12, derived from GlcNAc, cannot form such a H-bond; the (R,R)-isomer dominates (R/S 85:15; Scheme 3). The 2,3-di-O-benzyl-D-mannopyranosylidene diaziridines 20 and 22 adopt a 4C1 conformation, which does not allow an intramolecular H-bond; they are nearly 1:1 mixtures of R and S diastereoisomers, whereas the 0H5 conformation of the 2,3:5,6-di-O-isopropylidene-D-mannopyranosylidene diaziridines 24 is compatible with a weak, H-bond from the equatorial NH to O-C(2); the (R,R)-isomer is favoured (R/S ≥ 7:3: Scheme 6). The mannofuranosylidene diaziddine 31 completely prefers the (R,R)-configuration (Scheme 9).
- Bernet, Bruno,Mangholz, Sissi E.,Briner, Karin,Vasella, Andrea
-
p. 1488 - 1521
(2007/10/03)
-
- A new Co(0) complex mediated synthesis of C-glycoside analogues
-
Properly protected glyconolactones, readily available from the parent sugars, react under mild conditions with α-bromoacetates in the presence of a soluble Co(0) complex, either in stoichiometric or substoichiometric amounts, to give a Reformatsky-type addition product to the lactone. The addition product can be subsequently converted into a variety of compounds: dehydroxylation with triethylsilane in the presence of boron trifluoride affords C-glycosides.
- Orsini, Fulvia,Di Teodoro, Emanuela
-
p. 2521 - 2528
(2007/10/03)
-
- New stereoselective synthesis of phosphono analogues of glycosyl phosphates
-
A new and stereoselective synthesis of isosteric phosphono analogues of glycosyl phosphates is reported. Appropriately protected glyconolactones, easily available from the parent sugars are reacted with ethyl-α-iodomethylphosphonate in THF in the presence of a soluble low-valent cobalt-phosphine complex, either in stoichiometric or sub-stoichiometric amounts, in the latter case in the presence of magnesium metal. The use of magnesium metal alone works, but in a less efficient and predictable way. The intermediate addition product can be subsequently deoxygenated with triethylsilane in the presence of boron trifluoride.
- Orsini,Di Teodoro
-
p. 1307 - 1313
(2007/10/03)
-
- Thiazole as leaving group. Thermal elimination from thiazolylketoses
-
Heating thiazolylketofuranoses and -ketopyranoses in refluxing toluene results in the elimination of thiazole and formation of the corresponding sugar lactones in nearly quantitative yield. The same reaction does not occur with 1-O-acetyl and 1-O-trimethylsilyl derivatives. Also model furyl- and thienylketofuranoses and various thiazolyl alcohols proved to be stable under the above thermolysis conditions. A possible mechanism of the observed thermolysis of thiazolylketoses involves the thiazolium 2-ylide as the actual leaving group.
- Dondoni, Alessandro,Marra, Alberto
-
p. 419 - 426
(2007/10/03)
-
- Benzylation of aldonolactones with benzyl trichloroacetimidate
-
A number of aldono-1,4-lactones have been converted to their perbenzylated derivatives by treatment with benzyl trichloroacetimidate. 2,3,6-Trideoxy-D-erythro-hexono-1,4-lactone could be benzylated in dichloromethane, but lactones containing two or more h
- Jensen, Hanne Stampe,Limberg, Gerrit,Pedersen, Christian
-
p. 109 - 112
(2007/10/03)
-
- Synthesis and glycosylation of thio-D-fructofuranoside donors
-
Two ethyl thioglycosides of D-fructofuranose 4a and 4b, synthesized from D-arabinose and differentially protected at position 1 and 6, react with bulky acceptors in the presence of IDCP giving only α-fructofuranosides in essentially quantitative yields.
- Li, Yun-Long,Wu, Yu-Lin
-
p. 7413 - 7416
(2007/10/03)
-
- Synthesis of N-Tosylglycono-1,4-lactone Hydrazones as Precursors of Glycofuranosylidene Carbenes
-
The N'-(glycofuranosylidene)toluene-4-sulfonohydrazides 5 and 10 (Scheme 1) were prepared in good yields by oxidation (1,3-dibromo-5,5-dimethylhydantoin/Et3N) of the N'-glycosyltoluene-4-sulfonohydrazides 4 and 9, which were obtained from 2,3,5-tri-O-benz
- Mangholz, Sissi E.,Vasella, Andrea
-
p. 1020 - 1035
(2007/10/02)
-
- Thiazole-based synthesis of formyl C-glycosides
-
A method for the installation of the formyl group at the anomeric position of pyranoses and furanoses starting from the corresponding lactones has been developed. The strategy involves the addition of 2-lithiothiazole to the sugar lactone, followed by the silane reduction of the acetylated resultant ketol and the unmasking of the formyl group from the thiazole ring. All steps have been studied in some details to improve chemical efficiency and stereochemical control. Hence, reversed α:β ratios of ketols were found in kinetic and thermodynamic mixtures, the former being consistent with a steric effect control of the substituents and the latter by the electronic effect of the ring oxygen. Seven sugar aldehydes with different D-pyranosidic (2,3,4,6-tetra-O-benzyl-gluco, -galacto, and -manno, 2-azido-3,4,6-tri-O-benzyl-2-deoxy-galacto) and D-furanosidic moieties (5-O-benzyl-2,3-isopropylidene-ribo; 2,3,5-tri-O-benzyl-ribo; 2,3:5,6-di-O-isopropylidene-manno) were prepared in 52-65% isolated overall yield from the corresponding lactone.
- Dondoni,Scherrmann
-
p. 6404 - 6412
(2007/10/02)
-
- Synthetic approaches toward glidobamine, the core structure of the glidobactin antibiotics
-
Peptide synthesis method was first employed to synthesize glidobamine, the core structure of the glidobactin antibiotics (2), but in a model study all attempts failed to cyclize the linear precursor 10. Then a N-N bond cleavage method was developed to con
- Meng, Qingchang,Hesse, Manfred
-
p. 6251 - 6264
(2007/10/02)
-
- Concise Syntheses of 3-Methylenetetrahydrofuran-2-one Derivatives and Related Systems
-
Using the Shapiro reaction, the title compounds were prepared in 'one pot' from the consideration of two ketones, or an aldehyde and a ketone, with carbon dioxide.For example, acetone 2,4,6-tri-isopropylbenzenesulphonylhydrazone was treated in sequence with n-butyl-lithium (-50 deg C), acetone (-50 deg C), n-butyl-lithium (-78 to 0 to -78 deg C), carbon dioxide (-78 deg C), and trifluoroacetic acid (25 deg C) to give 5,5-dimethyl-3-methylenetetrahydrofuran-2-one.The reaction was extended to prepare derivatives of 3-methylenetetrahydropyran-2-one and 3,5-dimethylenetetrahydrofuran-2-one.
- Adlington, Robert M.,Barrett, Anthony G. M.
-
p. 2848 - 2863
(2007/10/02)
-