Some observations relating to the use of 1-aryl-4-alkoxypiperidin-4-yl groups for the protection of the 2′-hydroxy functions in the chemical synthesis of oligoribonucleotides
作者:Wayne Lloyd、Colin B. Reese、Quanlai Song、Anthony M. Vandersteen、Cristina Visintin、Pei-Zhou Zhang
DOI:10.1039/a908149f
日期:——
The comparative rates of acid-catalysed removal of ten 1-aryl-4-methoxypiperidin-4-yl 8 (RÂ =Â Me) [including the previously reported Ctmp 5 and Fpmp 6] protecting groups for the 2â²-hydroxy functions in oligoribonucleotide synthesis are discussed. These studies have led to the development of the 1-(4-chlorophenyl)-4-ethoxypiperidin-4-yl (Cpep) protecting group 8 (RÂ =Â Et, R1Â =Â R2Â =Â H, R3Â =Â Cl) which is both more stable than the Ctmp and Fpmp groups at pH 0.5 and more labile at pH 3.75. The influence of the ribonucleoside aglycone on the stability of the 2â²-O-Fpmp and 2â²-O-Ctmp protecting groups both at low and high pH is examined.
An acetal group suitable for the protection of 2′-hydroxy functions in rapid oligoribonucleotide synthesis
作者:Colin B Reese、Halina T Serafinowska、Giovanni Zappia
DOI:10.1016/s0040-4039(00)84511-6
日期:——
as in ()] has an acid lability similar to that of the 4-methoxytetrahydropyran-4-yl (Mthp) protecting group under mild hydrolytic conditions [pH 2–3]; however, under the relatively more drastic conditions required for the complete removal of a 9-phenylxanthen-9-yl (Px) group, the Ctmp protecting group remains virtually intact.