| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1346894 | Tetrahedron: Asymmetry | 2011 | 7 Pages |
The synthesis of d-fagomine and its stereoisomer, d-3,4-di-epi-fagomine has been achieved from C2-symmetric 3,4-bis-silyl substituted adipic acid di-oxazolidin-2-one derivatives via stereocontrolled azidation and silicon to hydroxyl conversion as the key steps. The Evans oxazolidin-2-one controlled the stereochemical outcome of the azidation which supersedes the directing effects of the silyl substituent.
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(4S,4′S)-3,3′-(2,2′-((3R,4R)-2,2,5,5-Tetramethyl-1,2,5-oxadisilolane-3,4-diyl)bis(acetyl))bis(4-isopropyloxazolidin-2-one)C22H38N2O7Si2Ee = >99%[α]D27=+152.9 (c 0.9, EtOH)Source of chirality: asymmetric induction and (S)-valineAbsolute configuration: (4S,4′S) (3R,4R)
(4S,4′S)-3,3′-(2,2′-((3S,4S)-2,2,5,5-Tetramethyl-1,2,5-oxadisilolane-3,4-diyl)bis(acetyl))bis(4-isopropyloxazolidin-2-one)C22H38N2O7Si2Ee = >99%[α]D28=-5.3 (c 0.87, EtOH)Source of chirality: asymmetric induction and (S)-valineAbsolute configuration: (4S,4′S) (3S,4S)
(S)-3-((R)-2-Azido-2-((3R,4R)-4-(2-((S)-4-isopropyl-2-oxooxazolidin-3-yl)-2-oxoethyl)-2,2,5,5-tetramethyl-1,2,5-oxadisilolan-3-yl)acetyl)-4-isopropyloxazolidin-2-oneC22H37N5O7Si2De = >99%Ee = >99%[α]D25=+89.8 (c 1.06, CHCl3)Source of chirality: asymmetric induction and (S)-valineAbsolute configuration: (4S,4′S) (2R,3R,4R)
(S)-3-((R)-2-((tert-Butyloxycarbonyl)amino)-2-((3R,4R)-4-(2-((S)-4-isopropyl-2-oxooxazolidin-3-yl)-2-oxoethyl)-2,2,5,5-tetramethyl-1,2,5-oxadisilolan-3-yl)acetyl)-4-isopropyloxazolidin-2-oneC27H47N3O9Si2De = >99%Ee = >99%[α]D23=+139.9 (c 1.07, CHCl3)Source of chirality: asymmetric induction and (S)-valineAbsolute configuration: (4S,4′S) (2R,3R,4R)
(R)-Methyl 2-((tert-butyloxycarbonyl)amino)-2-((3R,4R)-4-(2-methoxy-2-oxoethyl)-2,2,5,5-tetramethyl-1,2,5-oxadisilolan-3-yl)acetateC17H33NO7Si2De = >99%Ee = >99%[α]D25=+49.2 (c 1.2, CHCl3)Source of chirality: asymmetric inductionAbsolute configuration: (2R,3R,4R)
(3aR,4R,7aR)-Methyl octahydro-1,1,3,3-tetramethyl-6-oxo-[1,2,5]oxadisilolo[3,4-c]pyridine-4-carboxylateC11H21NO4Si2De = >99%Ee = >99%[α]D25=-20.0 (c 1.0, CHCl3)Source of chirality: asymmetric inductionAbsolute configuration: (3R,4R,7R)
(S)-3-((R)-2-Azido-2-((3S,4S)-4-(2-((S)-4-isopropyl-2-oxooxazolidin-3-yl)-2-oxoethyl)-2,2,5,5-tetramethyl-1,2,5-oxadisilolan-3-yl)acetyl)-4-isopropyloxazolidin-2-oneC22H37N5O7Si2De = >99%Ee = >99%[α]D28=+35.8 (c 1.01, MeOH)Source of chirality: asymmetric induction and (S)-valineAbsolute configuration: (4S,4′S) (2R,3S,4S)
(S)-3-((R)-2-((tert-Butyloxycarbonyl)amino)-2-((3S,4S)-4-(2-((S)-4-isopropyl-2-oxooxazolidin-3-yl)-2-oxoethyl)-2,2,5,5-tetramethyl-1,2,5-oxadisilolan-3-yl)acetyl)-4-isopropyloxazolidin-2-oneC27H47N3O9Si2De = >99%Ee = >99%[α]D28=+46.7 (c 1.01, CHCl3)Source of chirality: asymmetric induction and (S)-valineAbsolute configuration: (4S,4′S) (2R,3S,4S)
(R)-Methyl 2-((tert-butyloxycarbonyl)amino)-2-((3S,4S)-4-(2-methoxy-2-oxoethyl)-2,2,5,5-tetramethyl-1,2,5-oxadisilolan-3-yl)acetateC17H33NO7Si2De = >99%Ee = >99%[α]D28=-11.0 (c 1.02, CHCl3)Source of chirality: asymmetric inductionAbsolute configuration: (2R,3S,4S)
(3aS,4R,7aS)-Methyl octahydro-1,1,3,3-tetramethyl-6-oxo-[1,2,5]oxadisilolo[3,4-c]pyridine-4-carboxylateC11H21NO4Si2De = >99%Ee = >99%[α]D27=+80.9 (c 0.88, CHCl3)Source of chirality: asymmetric inductionAbsolute configuration: (3S,4R,7S)
