Dependence of the hydrolysis rate of a series of N-methoxy-2phenyl-1,3-oxazinanes on the Hammett substituent constant of the substituent of the phenyl ring was determined, yielding a reaction constant 1 = À 1.40 � 0.05. Based on this information, 4-(benzoyloxy)benzaldehyde was selected as a protecting group for a new (2R,3S)-4-(methoxyamino)butane-1,2,3-triol phosphoramidite building block. The yield of the preparation of this building block as well as its coupling in automated oligonucleotide synthesis were greatly improved compared to the method reported previously. The 2-[4-(benzoyloxy)phenyl]-1,3-oxazine protection persisted throughout the synthesis of short oligonucleotides but was rapidly removed when the oligonucleotides were released from solid support and dissolved in water.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.