Stereoselective Synthesis of the Isosteric Phosphono Analogues of N-Acetyl-α-d-glucosamine 1-Phosphate and N-Acetyl-α-d-mannosamine 1-Phosphate
摘要:
The isosteric phosphono analogues of N-acetyl-alpha-D-glucosamine I-phosphate and N-acetyl-alpha-D-mannosamine l-phosphate (1 and 2) are stereoselectively synthesized starting from 2,3,5-tri-O-benzyl-D-arabinose (3b). Reaction of 3b with divinylzinc stereoselectively affords the glucoenitol 4c, the mercuriocyclization and subsequent iododemercuriation of which stereoselectively afford the alpha-C-glucopyranosyl iodide 6b with a free hydroxyl group at C-2. Temporary protection of the hydroxyl group and treatment with triethyl phosphite converts 6b into the corresponding phosphonate 7b. The free hydroxyl group of 7b is then converted into an acetamido group by oximation, acetylation of the oxime, reduction, and subsequent acetylation. The reduction of the oxime with diborane stereoselectively affords the gluco isomer, whereas catalytic hydrogenation gives the manno isomer. Acetylation and deprotection afford the desired products 1 and 2.
Stereoselective Synthesis of the Isosteric Phosphono Analogues of N-Acetyl-α-d-glucosamine 1-Phosphate and N-Acetyl-α-d-mannosamine 1-Phosphate
摘要:
The isosteric phosphono analogues of N-acetyl-alpha-D-glucosamine I-phosphate and N-acetyl-alpha-D-mannosamine l-phosphate (1 and 2) are stereoselectively synthesized starting from 2,3,5-tri-O-benzyl-D-arabinose (3b). Reaction of 3b with divinylzinc stereoselectively affords the glucoenitol 4c, the mercuriocyclization and subsequent iododemercuriation of which stereoselectively afford the alpha-C-glucopyranosyl iodide 6b with a free hydroxyl group at C-2. Temporary protection of the hydroxyl group and treatment with triethyl phosphite converts 6b into the corresponding phosphonate 7b. The free hydroxyl group of 7b is then converted into an acetamido group by oximation, acetylation of the oxime, reduction, and subsequent acetylation. The reduction of the oxime with diborane stereoselectively affords the gluco isomer, whereas catalytic hydrogenation gives the manno isomer. Acetylation and deprotection afford the desired products 1 and 2.
Synthesis of stable C-phosphonate analogues of Neisseria meningitidis group A capsular polysaccharide structures using modified Mitsunobu reaction conditions
Examples of synthetic C-phosphonate analogues of microbial polysaccharide structures containing inter-residue phosphodiester linkages are most rare. The successful construction of such analogues of the Neisseria meningitidis Group A capsular polysaccharide is described. Using a modified Mitsunobu reaction (tris(4-chlorophenyl)phosphine, DIAD, excess of Et3N) between an anomeric C-phosphonate monoester
treatment of the iodide with triethylphosphite to afford the corresponding phosphonate, deprotection of the hydroxy group, oxidation, oximation, catalytic hydrogenation and acetylation, afford the phosphonoanalogue of N-acetyl-α-D-mannosamine 1-phosphate.
Carbohydrate Phosphonate Derivatives as Modulators of Glycosylation
申请人:AMGEN INC.
公开号:US20150376221A1
公开(公告)日:2015-12-31
Compounds of Formula (I) are useful as modulators of glycosylation. Compounds of Formula (I) have the following structure: (I) and the definitions of the other variables are provided herein.
化合物I的公式对糖基化的调节剂非常有用。化合物I的结构如下:(I),其他变量的定义在此提供。
Carbohydrate phosphonate derivatives as modulators of glycosylation
申请人:AMGEN INC.
公开号:US09328134B2
公开(公告)日:2016-05-03
Compounds of Formula (I) are useful as modulators of glycosylation. Compounds of Formula (I) have the following structure: (I) and the definitions of the other variables are provided herein.