An iodocyclization approach toward diastereoselective synthesis of highly functionalized tetrasubstituted tetrahydrofurans with 2,5-trans and 2,5-cis relationships from pyranoside derived acyclic oximes

An efficient method to obtain novel tetrasubstituted tetrahydrofurans with C2 and C5 substitution in trans- and cis-relative configurations has been reported.

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(1′E,2S,3R,4S,5R) 3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-benzyloximeC20H22NO4I[α]D = +29.4 (c 0.18, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′E,2S,3R,4S,5R)

(1′E,2S,3R,4S,5R) 3-Benzyloxy-4-acetyloxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-benzyl oximeC22H24NO5I[α]D = +156.8 (c 0.19, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′E,2S,3R,4S,5R)

(1′Z,2S,3R,4S,5R) 3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-benzyl oximeC20H22NO4I[α]D = +141.25 (c 0.16, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′Z,2S,3R,4S,5R)

(1′E,2S,3R,4S,5S) 3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-benzyl oximeC20H22NO4I[α]D = −7.5 (c 0.16, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′E,2S,3R,4S,5S)

(1′Z,2S,3R,4S,5S) 3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-benzyl oximeC20H22NO4I[α]D = +114.0 (c 0.05, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′Z,2S,3R,4S,5S)

(1′E,2S,3R,4S,5R)-3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-methyl oximeC14H18NO4I[α]D = +60.0 (c 0.28, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′E,2S,3R,4S,5R)

(1′Z,2S,3R,4S,5R)-3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-methyl oximeC14H18NO4I[α]D = +69.8 (c 0.41, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′Z,2S,3R,4S,5R)

(1′E,2S,3R,4S,5S)-3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-methyl oximeC14H18NO4I[α]D = −11.1 (c 0.18, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′E,2S,3R,4S,5S)

(1′E,2R,3R,4S,5R) 3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-benzyl oximeC20H22NO4I[α]D = +61.9 (c 0.36, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′E,2R,3R,4S,5R)

(1′Z,2R,3R,4S,5R) 3-Benzyloxy-4-hydroxy-5-iodomethyl tetrahydrofuran-2-carbaldehyde O-benzyl oximeC20H22NO4I[α]D = −47.3 (c 0.26, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1′Z,2R,3R,4S,5R)