Nucleic Acid-Related Compounds. 88. Efficient Conversions of Ribonucleosides into Their 2',3'-Anhydro, 2'(and 3')-Deoxy, 2',3'-Didehydro-2',3'-dideoxy, and 2',3'-Dideoxynucleoside Analogs
摘要:
Treatment of purine, pyrimidine, and modified purine (antibiotic) ribonucleosides with 2-acetoxy-2-methylpropanoyl (alpha-acetoxyisobutyryl) bromide in acetonitrile gave mixtures of 2',3'-bromohydrin acetates with different O5' substituents. Significant amounts of 5'-unprotected (hydroxyl) bromo acetates were obtained in some cases, and formation of 2',3'-O-isopropylidene derivatives as minor byproducts was detected for the first time. Acid-catalyzed nucleophilic displacement of chloride by bromide occurred with 2-amino-6-chloropurine riboside, but no substitution of fluoride by bromide was detected with 6-amino-2-fluoropurine riboside. Treatment of the trans bromo acetate mixtures obtained from purine-type nucleosides with Dowex 1 x 2 (OH-) in methanol gave the 2',3'-anhydro (ribo epoxide) compounds. Radical-mediated hydrogenolytic debromination and deprotection gave 2'- and 3'-deoxynucleosides. Treatment of the bromo acetate mixtures with zinc-copper couple or acetic acid-activated zinc effected reductive elimination, and deprotection gave 2',3'-didehydro-2',3'-dideoxy compounds which were hydrogenated to give 2',3'-dideoxynucleosides. A number of these analogues have potent inhibitory activity against AIDS and hepatitis B viruses. New C-13 NMR data for several types of unsaturated-sugar nucleosides are tabulated. These procedures are directly applicable for the preparation of L-didehydro-dideoxy and L-dideoxy nucleoside analogues.
Nucleic Acid-Related Compounds. 88. Efficient Conversions of Ribonucleosides into Their 2',3'-Anhydro, 2'(and 3')-Deoxy, 2',3'-Didehydro-2',3'-dideoxy, and 2',3'-Dideoxynucleoside Analogs
摘要:
Treatment of purine, pyrimidine, and modified purine (antibiotic) ribonucleosides with 2-acetoxy-2-methylpropanoyl (alpha-acetoxyisobutyryl) bromide in acetonitrile gave mixtures of 2',3'-bromohydrin acetates with different O5' substituents. Significant amounts of 5'-unprotected (hydroxyl) bromo acetates were obtained in some cases, and formation of 2',3'-O-isopropylidene derivatives as minor byproducts was detected for the first time. Acid-catalyzed nucleophilic displacement of chloride by bromide occurred with 2-amino-6-chloropurine riboside, but no substitution of fluoride by bromide was detected with 6-amino-2-fluoropurine riboside. Treatment of the trans bromo acetate mixtures obtained from purine-type nucleosides with Dowex 1 x 2 (OH-) in methanol gave the 2',3'-anhydro (ribo epoxide) compounds. Radical-mediated hydrogenolytic debromination and deprotection gave 2'- and 3'-deoxynucleosides. Treatment of the bromo acetate mixtures with zinc-copper couple or acetic acid-activated zinc effected reductive elimination, and deprotection gave 2',3'-didehydro-2',3'-dideoxy compounds which were hydrogenated to give 2',3'-dideoxynucleosides. A number of these analogues have potent inhibitory activity against AIDS and hepatitis B viruses. New C-13 NMR data for several types of unsaturated-sugar nucleosides are tabulated. These procedures are directly applicable for the preparation of L-didehydro-dideoxy and L-dideoxy nucleoside analogues.
Synthesis and Evaluation of Certain Thiosangivamycin Analogs as Potential Inhibitors of Cell Proliferation and Human Cytomegalovirus
作者:Steven H. Krawczyk、Thomas E. Renau、M. Reza Nassiri、Allison C. Westerman、Linda L. Wotring、John C. Drach、Leroy B. Townsend
DOI:10.1021/jm00020a027
日期:1995.9
7-substituted 4-aminopyrrolo[2,3-d]pyrimidines related to the nucleosides toyocamycin and thiosangivamycin were prepared and tested for their activity against human cytomegalovirus (HCMV). The nucleosides 2'-deoxytoyocamycin (1), xylo-toyocamycin (2), 3'-deoxytoyocamycin (3), 2',3'-dideoxy-2',3'-didehydrotoyocamycin (4), 2',3'-dideoxytoyocamycin (5), ara-toyocamycin (6), 2'-deoxy-2'-amino-ara-toyocamycin
Compositions and methods for pyrrolo[2,3-d]pyrimidine nucleoside analogs having substituents at the C4′ and C5′ positions of the ribofuranose moiety are presented. Contemplated compositions exhibit, among other things, anti-cancer and immunomodulating effects at reduced cytotoxicity.