- Diastereoselective synthesis of (1,3-Dioxan-4-yl)pyrimidine and purin nucleoside analogues
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(1,3-Dioxan-4-yl)-substituted nucleoside analogues, higher homologues of antiviral and anticancer 1,3-dioxolanes, were prepared from the key intermediate (4-acetoxy-1,3-dioxan- 2-yl)methyl benzoate and silylated bases. Glycosylation, carried out under Vorbrüggen conditions in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) as a catalyst, afforded the desired compounds with high stereoselecti- vity and regioselectivity, with only the desired β-anomeric N- 1 pyrimidine and N-9 purin nucleosides being obtained. 1H NMR experiments established that the β-anomers were diequatorial, and this assignment was confirmed by singlecrystal X-ray diffraction. Despite their structural similarities with natural nucleosides, none of the synthesized nucleosides showed antiviral activity.
- Battisti, Umberto M.,Sorbi, Claudia,Quotadamo, Antonio,Franchini, Silvia,Tait, Annalisa,Schols, Dominique,Jeong, Lak Shin,Lee, Sang Kook,Song, Jayoung,Brasili, Livio
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- A New and Versatile Synthesis of 1,3-Dioxan-5-yl-pyrimidine and Purine Nucleoside Analogues
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1,3-Dioxan-5-yl pyrimidine and purine nucleoside analogues were prepared following a new and versatile synthetic strategy. These analogues were synthesized via nucleophilic addition of the selected nucleobase to a 1,3-dioxane scaffold that presents an appropriate leaving group in position 5. In particular cis and trans isomers of purine/pyrimidine nucleosides and their halogenated homologues were obtained. NMR experiments, carried out on the cis isomers, led to assignment of an equatorial orientation to the 2-hydroxymethyl group and axial orientation to the nucleobase in position 5 of the 1,3-dioxane. The trans isomers showed a diequatorial orientation of these groups. These assignments were confirmed by X-ray crystallographic studies.
- Sorbi, Claudia,Prandi, Adolfo,Battisti, Umberto M.,Franchini, Silvia,Cornia, Andrea,Balzarini, Jan,Jeong, Lak Shin,Lee, Sang Kook,Song, Jayoung,Brasili, Livio
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- Preparation of renieramycin left-half model compounds
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Model compounds of the left-half of renieramycins, which are anticancer marine natural products having an α-aminonitrile functionality, were prepared from phenylalanine derivatives. The key step of the transformation is the stereospecific construction of 1,3-cis stereochemistry via an exomethylene intermediate. The stereoselective α-aminonitrile formation under kinetically controlled conditions is also discussed. The initial cytotoxicity profiles are presented.
- Nakai, Keiyo,Kubo, Keiji,Yokoya, Masashi,Saito, Naoki
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- Synthesis, structure, and conformational analysis of nucleoside analogues comprising six-membered 1,3-oxathiane sugar rings
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We report on the synthesis, characterization, and conformational analysis of 1,3-oxathiane nucleosides of both pyrimidine and purine nucleobases. The novel nucleoside analogues were prepared from readily available starting materials as α/β anomeric mixtur
- Abou Assi, Hala,Martínez-Montero, Saúl,Dixit, Dilip M.,Chua, Zhijie,Bohle, D. Scott,Damha, Masad J.
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- IRAK DEGRADERS AND USES THEREOF
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The present invention provides compounds, compositions thereof, and methods of using the same.
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Paragraph 00962; 003707-003709
(2020/06/19)
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- Aminoglycoside type derivative and preparing method and application thereof
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The invention provides an aminoglycoside type derivative and a preparing method and application thereof. The aminoglycoside type derivative is a novel aminoglycoside type derivative. According to thederivative, the C2' amino position and the C6' amino pos
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Paragraph 0069-0072
(2018/05/30)
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- Diversity-oriented synthesis of cyclopropyl peptides from Ugi-derived dehydroalanines
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A three-step synthesis of cyclopropyl peptides is reported. The protocol involves a consecutive Ugi-4CR/elimination reaction to prepare dehydroalanines followed by a Corey-Chaykovsky cyclopropanation reaction. Peptide-like molecules that resemble some pharmacologically active compounds with a variety of substituents in the cyclopropane ring were prepared. When (2-ethoxy-2-oxoethyl) dimethyl sulfonium ylide was used the reaction exclusively gives the cis-diastereoisomer cyclopropanes in good yields from readily prepared starting materials. A collection of 26 highly substituted cyclopropyl peptides were obtained.
- Contreras-Cruz, David A.,Sánchez-Carmona, Miguel A.,Vengoechea-Gómez, Fabio A.,Pe?a-Ortíz, Daniel,Miranda, Luis D.
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supporting information
p. 6146 - 6156
(2017/09/29)
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- Synthetic studies on saframycin anibiotics: an improved synthesis of tricyclic lactam intermediate and construction of the core ring system of saframycin A
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An improved synthesis of the tricyclic lactam intermediate of saframycin antibiotics and the construction of the core ring system having a cyano group at C-21 position were presented.1 The stereochemistry of several key intermediates was determined by X-r
- Kimura, Shinya,Kawai, Shintaro,Azuma, Masayuki,Umehara, Yoshifumi,Koizumi, Yu-Ichi,Yokoya, Masashi,Saito, Naoki
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p. 327 - 343
(2015/03/04)
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- Process for Manufacture of Optically Active 2-(Acyloxymethyl)-1,3-Oxathiolanes
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There is provided a process for manufacture of optically-active, 2-(acyloxymethyl)-1,3-oxathiolanes of Formula I comprising a preparation of a racemic compound and an enzyme-catalyzed kinetic resolution of the enantiomers. The invention may further provid
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Page/Page column 9
(2012/06/30)
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- Process for Manufacture of Optically Active 2-(Acyloxymethyl)-1,3-Oxathiolanes
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There is provided a process for manufacture of optically-active, 2-(acyloxymethyl)-1,3-oxathiolanes of Formula I comprising a preparation of a racemic compound and an enzyme-catalyzed kinetic resolution of the enantiomers. The invention may further provide for the esterification and racemization of the by-product of the enzymatic reaction. In this manner, 2(R)-(benzoyloxymethyl)-1,3-oxathiolane is prepared as a useful intermediate for manufacture of the anti-HIV drug Apricitabine.
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- Benzimidazole compound
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An object of the present invention is to provide a novel chemical compound useful as a therapeutic or prophylactic agent for acid-related diseases, having an excellent inhibitory effect against gastric acid secretion, an excellent effect of maintaining the inhibitory effect against gastric acid secretion, thereby maintaining intragastric pH high for a long time, and having more safety and appropriate physicochemical stability. Provided is a compound represented by where R1 and R3 may be the same or different and each represent a hydrogen atom or a C1-C6 alkyl group; R2 represents (5,5-dimethyl-1,3-dioxan-2-yl)methoxy group, 5,7-dioxaspiro[2.5]oct-6-ylmethoxy group, 1,5,9-trioxaspiro[5.5]undec-3-ylmethoxy group, or (2,2-dimethyl-1,3-dioxan-5-yl)methoxy group; R4, R5, R6 and R7 represent a hydrogen atom, halogen atom, C1-C6 alkyl group, C1-C6 haloalkyl group, C1-C6 alkoxy group or C1-C6 haloalkoxy group; and W1 represents a single bond, methylene or ethylene group, a salt thereof or a solvate of these.
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Page/Page column 95
(2008/06/13)
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- Process for producing 2-benzoyloxyacetaldehyde derivative
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A process produces a 2-benzoyloxyacetaldehyde derivative represented by following Formula (3): wherein R1 and R2 may be the same as or different from each other and are each a hydrocarbon group, wherein R1 and R2 may be combined to form a ring with the adjacent oxygen-carbon-oxygen bond, and wherein the benzene ring in the formula may be substituted, by allowing a halogenated acetaldehyde acetal derivative represented by following Formula (1): wherein R1 and R2 are as defined above; and X represents a halogen atom, to react with a benzoate represented by following Formula (2): wherein M represents an alkali metal atom and wherein the benzene ring in the formula may be substituted, in the presence of an alkali-metal halide.
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Page/Page column 4
(2008/06/13)
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- Facile preparation of α-acyloxyacetaldehyde, a versatile intermediate in the synthesis of antiviral nucleosides
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This report describes a novel and simple method for the preparation of a versatile intermediate, α-acyloxyacetaldehyde and its acetals, and its application to the synthesis of 4-acetoxy-2-acyloxymethyl-1,3-oxathiolane, an important intermediate in the syn
- Du, Jinfa,Watanabe, Kyoichi A.
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p. 1925 - 1930
(2007/10/03)
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- Preparation of intermediates useful in the synthesis of antiviral nucleosides
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The present invention is an efficient process for the manufacture of α-acyloxyacetaldehyde, a key intermediate in the synthesis of 1,3-oxathiolane and 1,3-dioxolane nucleosides.
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- Analogues of the Antiviral Acyclonucleoside 9-(4-Hydroxy-3-hydroxymethylbutyl)guanine. Part 1. Substitutions on C-2' of the Acyclic N-9 Substituent
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Syntheses of 9-(4-hydroxy-3-hydroxymethyl-2-methylbutyl)guanine (4), 9-(4-hydroxy-3-hydroxymethyl-2-methoxybutyl)guanine (5), 9-guanine (6), 9-(2,4-dihydroxy-3-hydroxymethylbutyl)guanine (7), and 9-(2-fluoro-4-hydrox
- Harnden, Michael R.,Parkin, Ann,Wyatt, Paul G.
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p. 2757 - 2766
(2007/10/02)
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