- Structure-based rationalization of aldolase-catalyzed asymmetric synthesis
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This paper describes a structure-based approach to elucidate the stereospecificity, including inversion of enantioselectivity, of the 2-deoxyribose-5-phosphate aldolase-catalyzed asymmetric aldol addition reaction using unnatural substrates designed for t
- Liu, Junjie,DeSantis, Grace,Wong, Chi-Huey
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- 2-deoxy-L-ribose preparation method
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The invention relates to a method for preparing 2-deoxidation-L-ribose based on L-arabinose as a raw material. The method comprises following seven steps: protection, group activation, transformation, deprotection and purification. Synthesis reaction cond
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Paragraph 0022; 0048-0050
(2017/04/08)
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- Improved and practical synthesis of 2-deoxy-l-ribose by hypophosphite-mediated deoxygenation
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An improved and practical route for a large-scale synthesis of 2-deoxy-L-ribose starting from L-arabinose has been developed. This is the first reported synthesis of 2-deoxy-L-ribose in which deoxygenation has been mediated by hypophosphite reagents instead of by organotin reagents.
- Chen, Li-Li,Ming, Xun,Cen, Jun-Da
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experimental part
p. 1 - 7
(2011/10/31)
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- Stability of N-glycosidic bond of (5′ S)-8,5′-Cyclo-2′- deoxyguanosine
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8,5′-Cyclopurine deoxynucleosides are unique tandem lesions containing an additional covalent bond between the base and the sugar. These mutagenic and genotoxic lesions are repaired only by nucleotide excision repair. The N-glycosidic (or C1′-N9) bond of 2′-deoxyguanosine (dG) derivatives is usually susceptible to acid hydrolysis, but even after cleavage of this bond of the cyclopurine lesions, the base would remain attached to the sugar. Here, the stability of the N-glycosidic bond and the products formed by formic acid hydrolysis of (5′S)-8,5′-cyclo-2′-deoxyguanosine (S-cdG) were investigated. For comparison, the stability of the N-glycosidic bond of 8,5′-cyclo-2′,5′-dideoxyguanosine (ddcdG), 8-methyl-2′-deoxyguanosine (8-Me-dG), 7,8-dihydro-8-oxo-2′- deoxyguanosine (8-Oxo-dG), and dG was also studied. In various acid conditions, S-cdG and ddcdG exhibited similar stability to hydrolysis. Likewise, 8-Me-dG and dG showed comparable stability, but the half-lives of the cyclic dG lesions were at least 5-fold higher than those of dG or 8-Me-dG. NMR studies were carried out to investigate the products formed after the cleavage of the C1′-N9 bond. 2-Deoxyribose generated α and β anomers of deoxyribopyranose and deoxyribopyranose oligomers following acid treatment. S-cdG gave α- and β-deoxyribopyranose linked guanine as the major products, but α and β anomers of deoxyribofuranose linked guanine and other products were also detected. The N-glycosidic bond of 8-Oxo-dG was found exceptionally stable in acid. Computational studies determined that both the protonation of the N7 atom and the rate constant in the bond breaking step control the overall kinetics of hydrolysis, but both varied for the molecules studied indicating a delicate balance between the two steps. Nevertheless, the computational approach successfully predicted the trend observed experimentally. For 8-Oxo-dG, the low pKa of O8 and N3 prevented appreciable protonation, making the free energy for N-glycosidic bond cleavage in the subsequent step very high.
- Das, Rajat S.,Samaraweera, Milinda,Morton, Martha,Gascon, Jose A.,Basu, Ashis K.
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p. 2451 - 2461
(2013/01/15)
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- A new synthetic strategy for 2-deoxy-D-ribose via palladium(II)-catalyzed cyclization of aldehyde
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We achieved a total synthesis of 2-deoxy-D-ribose through intramolecular Pd(II)-catalyzed cyclization of aldehyde via an unstable hemiacetal intermediate as a key step. The Japan Institute of Heterocyclic Chemistry.
- Miyazawa, Masahiro,Awasaguchi, Ken-Ichiro,Uoya, Ikuyo,Yokoyama, Hajime,Hirai, Yoshiro
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p. 1891 - 1902
(2011/04/12)
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- PREPARATION METHOD OF 2-DEOXY-L-RIBOSE
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A method of preparing 2-deoxy-L-ribose represented by the following formula I is disclosed. The preparation method includes the steps of: treating L-arabinose with an alcohol solvent in the presence of an acid to prepare 1-alkoxy-L-arabinopyranose; allowi
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Page/Page column 6
(2009/12/05)
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- THE PREPARATION METHOD OF 2-DE0XY-L-RIB0SE
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A method of preparing 2-deoxy-L-ribose represented by the following formula I is disclosed. The preparation method includes the steps of : treating L-arabinose with an alcohol solvent in the presence of an acid to prepare 1-alkoxy-L- arabinopyranose; allowing the prepared 1-alkoxy-L- arabinopyranose to react with acyl chloride so as to prepare l-alkoxy-2, 3, 4-triacyl-L-arabinopyranose; brominating the alkoxy group of the prepared l-alkoxy-2, 3, 4-triacyl-L- arabinopyranose to prepare a l-bromo-2, 3, 4-triacyl compound; allowing the prepared compound to react with zinc in the presence of ethyl acetate and an organic base so as to prepare glycal; treating the glycal with an alcohol solvent in the presence of an acid to prepare l-alkoxy-2-deoxy-3, 4- diacyl-L-ribopyranose; treating the prepared l-alkoxy-2- deoxy-3, 4-diacyl-L-ribopyranose with a base to prepare 1- alkoxy-2-deoxy-L-ribopyranose; and hydrolyzing the prepared l-alkoxy-2-deoxy-L-ribopyranose in the presence of an acid catalyst.
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Page/Page column title page; 19-20
(2008/12/06)
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- A simple and efficient synthesis of 2-deoxy-L-ribose from 2-deoxy-D-ribose
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An efficient synthesis of 2-deoxy-L-ribose was achieved without chromatography starting from its enantiomer 2-deoxy-D-ribose in more than 30% overall yield. An unexpected product, 2-deoxy-xylose, was obtained under slightly different reaction conditions a
- Ji, Qi,Pang, Meili,Han, Jie,Feng, Suihan,Zhang, Xiaotian,Ma, Yuxin,Meng, Jiben
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p. 2498 - 2500
(2008/02/11)
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- Production method of 2-deoxy-L-ribose compound
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An aldehyde compound represented by the formula (1) is reacted with an organometallic compound represented by the formula (2) to give an alcohol compound represented by the formula (3), which is then subjected to deprotection of a hydroxyl group and production of aldehyde by acid hydrolysis. wherein R1 and R2 are each independently a hydroxyl-protecting group or R1 and R2 in combination show a hydroxyl-protecting group, R3 and R4 are each independently an alkyl group, an aralkyl group, an aryl group or a silyl group or R3 and R4 in combination show a cyclic alkyl group.
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Page/Page column 15
(2010/02/13)
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- Synthesis of beta-L-2'-deoxy nucleosides
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An improved process for the preparation of 2′-modified nucleosides and 2′-deoxy-nucleosides, such as, β-L-2′-deoxy-thymidine (LdT), is provided. In particular, the improved process is directed to the synthesis of a 2′-deoxynucleoside that may utilize different starting materials but that proceeds via a chloro-sugar intermediate or via a 2,2′-anhydro-1-furanosyl-nucleobase intermediate. Where an 2,2′-anhydro-1-furanosyl base intermediate is utilized, a reducing agent, such as Red-Al, and a sequestering agent, such as 15-crown-5 ether, that cause an intramolecular displacement reaction and formation of the desired nucleoside product in good yields are employed. An alternative process of the present invention utilizes a 2,2′-anhydro-1-furanosyl base intermediate without a sequestering agent to afford 2′-deoxynucleosides in good yields. The compounds made according to the present invention may be used as intermediates in the preparation of other nucleoside analogues, or may be used directly as antiviral and/or antineoplastic agents.
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Page/Page column 19; 20
(2010/02/11)
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- METHOD FOR PRODUCING 2-DEOXY-L-RIBOSE
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The present invention relates to a economic synthetic method of 2-deoxy-L-ribose from 2-deoxy-D-ribose with easy reaction, separation and purification. The present invention consists of four(4) steps including protection, activation 3-and 4-OH groups, inv
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- Efficient synthesis of 2-deoxy-L-erythro-pentose (2-deoxy-L-ribose) from L-arabinose
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An efficient and practical route for the large-scale synthesis of 2-deoxy-L-erythro-pentose (2-deoxy-L-ribose) starting from L-arabinose was developed using Barton-type free-radical deoxygenation reaction as a key step. The radical precursor, a phenoxythi
- Chong, Youhoon,Chu, Chung K
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p. 397 - 402
(2007/10/03)
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- Aldolase-catalyzed asymmetric synthesis of novel pyranose synthons as a new entry to heterocycles and epothilones
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Enzymatic reactions catalyzed by DERA provide the basis for a new strategy for the synthesis of novel pyranose synthons. The utility of this very convergent and effective method is demonstrated by the concise total synthesis of epothilones (see scheme; DERA = 2-deoxyribose-5-phosphate aldolase).
- Liu, Junjie,Wong, Chi-Huey
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p. 1404 - 1407
(2007/10/03)
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- 2-Deoxy-L-ribose from an L-arabinono-1,5-lactone
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A practical synthesis of 2-deoxy-L-ribose from L-arabinose depends on the efficient reduction by iodide of a triflate α to a lactone. The X-ray crystal structure of 3,4-O-isopropylidene-L-arabinono-1,5-lactone is reported.
- Stewart, Alistair J.,Evans, Richard M.,Weymouth-Wilson, Alexander C.,Cowley, Andrew R.,Watkin, David J.,Fleet, George W. J.
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p. 2667 - 2672
(2007/10/03)
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- Synthesis of 2,6-dideoxysugars via ring-closing olefinic metathesis.
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[formula: see text] Grubbs' RuCl2 (=CHPh)(PCy3)2 (catalyst 1) and RuCl2(=CHPh)(PCy3)(IMess) (catalyst 2) complexes have been successfully utilized in the construction of beta,gamma-unsaturated delta-lactones containing various substitution patterns of methyl groups. Asymmetric dihydroxylation followed by reduction leads to 3,4-cis-dihydroxy-2,6-dideoxypyranoses, which have proven to play very important biological roles as key components of natural products.
- Andreana, Peter R,McLellan, Jason S,Chen, Yongchen,Wang, Peng George
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p. 3875 - 3878
(2007/10/03)
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- Synthesis of 3,5-O-benzylidene-2-deoxy-L-riboaldose from 5,5-dihydroxy- 2-phenyl-1,3-dioxane
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The asymmetric alkylation of 2-phenyl-1,3-dioxan-5-one was achieved via the RAMP-hydrazone. Regeneration of the ketone followed by stereoselective reduction and ozonolysis, gave the protected 2-deoxy-L-ribose, 3,5-O- benzyldiene-2-deoxy-L-erythro-pentoald
- Ulven, Trond,Carlsen, Per H. J.
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p. 2275 - 2280
(2007/10/03)
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- Preparation of 2-deoxyaldoses from aldose phenylhydrazones
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Acetylation of D-mannose phenylhydrazone gives acetylated D-arabino-1-phenyl-azo-1-(E)-hexene. Subsequent reduction with sodium borohydride produces 2-deoxy-D-arabino-hexose phenylhydrazone which, on hydrolysis, gives 2-deoxy-D-arabino-hexose. By a similar procedure 2-deoxy-D-lyxo-hexose, 2,6-dideoxy-L-arabino-hexose, and 2-deoxy-D-erythropentose can be prepared from D-galactose, L-rhamnose, and D-arabinose, respectively.
- Jorgensen, Christel,Pedersen, Christian
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p. 307 - 310
(2007/10/03)
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