The Experts below are selected from a list of 516 Experts worldwide ranked by ideXlab platform
Chung K. Chu - One of the best experts on this subject based on the ideXlab platform.
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Stereocontrolled syntheses of Carbocyclic C-nucleosides and related Compounds.
The Journal of organic chemistry, 2001Co-Authors: Byoung K. Chun, Gyu Y. Song, Chung K. ChuAbstract:Carbocyclic 9-deazapurine nucleosides (1−4), a spiranic pyrimidone Carbocyclic Compound (5), and an unusual Carbocyclic isonucleoside (6) were prepared as enantiomerically pure Compounds via the key intermediates 10 and 21 from 1,4-γ-ribonolactone. The key intermediate 10 was prepared by stereoselective reduction with Bu3SnH and then converted to Carbocyclic C-ribonucleosides 1, 3, and 4. 2‘,3‘-Didehydro-2‘,3‘-dideoxyCarbocyclic 9-deazainosine (2) was prepared from a 2‘,3‘-dimesylate 17 by treatment with Li2Te followed by an acidic deprotection. The key bicyclic intermediate 21 was prepared from a diol 20 by an intramolecular cyclization using CHI3−Ph3P−imidazole and converted to the spiranic Compound 5 and an olefinic nucleoside 6 by the construction of the heterocyclic moiety followed by deprotection.
Juan B. Rodriguez - One of the best experts on this subject based on the ideXlab platform.
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Synthetic studies toward the preparation of (4R,5R)-(−)-3-[(benzyloxy)methyl]-4,5-O-isopropylidene-cyclopenten-2-one: an important synthetic intermediate for carbanucleosides
Tetrahedron: Asymmetry, 2005Co-Authors: Eleonora Elhalem, Maria J. Comin, Julieta Leitofuter, Guadalupe García-liñares, Juan B. RodriguezAbstract:Abstract The Carbocyclic Compound (4R,5R)-(−)-3-[(benzyloxy)methyl]-4,5-O-isopropylidene-2-cyclopentenone 1 is an important synthetic intermediate to access a variety of carbanucleosides. Herein, synthetic studies that lead to this valuable Compound employing inexpensive d -ribose as the chiral source are presented.
Dennis G. Peters - One of the best experts on this subject based on the ideXlab platform.
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In-situ electrogeneration of [2,2′-ethylenebis(nitrilomethylidyne)diphenolato]nickelate(I) — nickel(I) salen — as a catalyst for reductive intramolecular cyclizations of 6-iodo- and 6-bromo-1-phenyl-1-hexyne
Journal of Electroanalytical Chemistry, 1992Co-Authors: Mohammad S. Mubarak, Dennis G. PetersAbstract:Abstract In dimethylformamide containing tetraethylammonium perchlorate, the [2,2′-ethylenebis(nitrilomethylidyne)diphenolato]nickel(II) complex, more familiarly known as nickel(II) salen, undergoes reversible one-electron reduction at a carbon cathode to the corresponding nickel(I) species at a potential where 6-iodo- and 6-bromo-1-phenyl-1-hexyne are not electroactive. However, in the presence of the electrogenerated nickel(I) complex, these acetylenic halides are rapidly and catalytically reduced to form a radical intermediate that cyclizes to produce benzylidenecyclopentane in at least 84% yield. This approach to the electrosynthesis of the Carbocyclic Compound is highly efficient because direct electrolyses of 6-iodo- and 6-bromo-1-phenyl-1-hexyne at carbon cathodes lead to undesired acyclic side-products and to benzylidenecyclopentane in only modest yields.
Byoung K. Chun - One of the best experts on this subject based on the ideXlab platform.
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Stereocontrolled syntheses of Carbocyclic C-nucleosides and related Compounds.
The Journal of organic chemistry, 2001Co-Authors: Byoung K. Chun, Gyu Y. Song, Chung K. ChuAbstract:Carbocyclic 9-deazapurine nucleosides (1−4), a spiranic pyrimidone Carbocyclic Compound (5), and an unusual Carbocyclic isonucleoside (6) were prepared as enantiomerically pure Compounds via the key intermediates 10 and 21 from 1,4-γ-ribonolactone. The key intermediate 10 was prepared by stereoselective reduction with Bu3SnH and then converted to Carbocyclic C-ribonucleosides 1, 3, and 4. 2‘,3‘-Didehydro-2‘,3‘-dideoxyCarbocyclic 9-deazainosine (2) was prepared from a 2‘,3‘-dimesylate 17 by treatment with Li2Te followed by an acidic deprotection. The key bicyclic intermediate 21 was prepared from a diol 20 by an intramolecular cyclization using CHI3−Ph3P−imidazole and converted to the spiranic Compound 5 and an olefinic nucleoside 6 by the construction of the heterocyclic moiety followed by deprotection.
Eleonora Elhalem - One of the best experts on this subject based on the ideXlab platform.
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Synthetic studies toward the preparation of (4R,5R)-(−)-3-[(benzyloxy)methyl]-4,5-O-isopropylidene-cyclopenten-2-one: an important synthetic intermediate for carbanucleosides
Tetrahedron: Asymmetry, 2005Co-Authors: Eleonora Elhalem, Maria J. Comin, Julieta Leitofuter, Guadalupe García-liñares, Juan B. RodriguezAbstract:Abstract The Carbocyclic Compound (4R,5R)-(−)-3-[(benzyloxy)methyl]-4,5-O-isopropylidene-2-cyclopentenone 1 is an important synthetic intermediate to access a variety of carbanucleosides. Herein, synthetic studies that lead to this valuable Compound employing inexpensive d -ribose as the chiral source are presented.