4-(Acetylthio)-2,2-dimethyl-3-oxobutyl and 4-(<i>tert</i>-Butyldisulfanyl)-2,2-dimethyl-3-oxobutyl as Protecting Groups for Nucleoside 5′-Phosphoramidates Derived from<scp>L</scp>-Alanine Methyl Ester
作者:Vyankat A. Sontakke、Harri Lönnberg、Mikko Ora
DOI:10.1002/ejoc.201500531
日期:2015.8
disulfide bond with glutathione from 2 triggers the removal of the protecting group by cyclization releasing quantitatively nucleoside 5′-N-[(1S)-2-oxo-2-methoxy-1-methylethyl]phosphoramidate} (7) as the desired product. With 1, enzymatic deacetylation or acetyl migration from the sulfur atom to the adjacent hydrated oxo group followed by chemical cyclization produces 7. The S–S-bond-mediated dimerization
Synthesis and Stability of Nucleoside 3′,5′-Cyclic Phosphate Triesters Masked with Enzymatically and Thermally Labile Phosphate Protecting Groups
作者:Vyankat A. Sontakke、Vaishali S. Shinde、Harri Lönnberg、Mikko Ora
DOI:10.1002/ejoc.201403227
日期:2015.1
Appropriately protected structurally modified nucleoside 3′,5′-cyclic monophosphates are known to show antiviral activity. For this reason, a straightforward synthesis of nucleoside 3′,5′-cyclic phosphates protected with three different enzymatically removable groups, viz. 3-acetyloxy-2,2-bis(ethoxycarbonyl)propyl (in 1 and 4), 4-acetylthio-2,2-dimethyl-3-oxobutyl (in 2), and 4-(tert-butyldisulfanyl)-2
4-Acetylthio-2,2-dimethyl-3-oxobutyl Group as an Esterase- and Thermo-Labile Protecting Group for Oligomeric Phosphodiesters
作者:Anna Leisvuori、Harri Lönnberg、Mikko Ora
DOI:10.1002/ejoc.201402412
日期:2014.9
(4-Acetylthio-2,2-dimethyl-3-oxobutyl)-protected oligomericphosphodiesters 1 and 2 were synthesized and removal of the protectinggroups in the presence and absence of hog liver esterase was followed at pH 7.5 and 37 °C. Phosphotriesters 1 and 2 were successfully converted into the desired fully deprotected phosphodiesters 3 and 4, respectively. Some cleavage of internucleosidic P–O bonds took place