Unit

UNIT 3.15 DNA Synthesis Without Base Protection Using the Phosphoramidite Approach

  1. Akihiro Ohkubo,
  2. Kohji Seio,
  3. Mitsuo Sekine

Published Online: 1 OCT 2006

DOI: 10.1002/0471142700.nc0315s26

Current Protocols in Nucleic Acid Chemistry

Current Protocols in Nucleic Acid Chemistry

How to Cite

Ohkubo, A., Seio, K. and Sekine, M. 2006. DNA Synthesis Without Base Protection Using the Phosphoramidite Approach. Current Protocols in Nucleic Acid Chemistry. 26:3.15:3.15.1–3.15.22.

Author Information

  1. Tokyo Institute of Technology, Tokyo, Japan

Publication History

  1. Published Online: 1 OCT 2006
  2. Published Print: SEP 2006

Abstract

In the strategy of DNA synthesis without base protection, a recent O-selective phosphorylation procedure known as the “activated phosphite method” is used to generate reactive phosphite intermediates from N-unprotected phosphoramidite building blocks. This new strategy proved to be advantageous over previous strategies because the cleavage of the N-P(III) bond, which can be formed by the significant phosphitylation of the nucleobase amino groups, can be omitted. The activated phosphite method provides an attractive route to high-throughput synthesis of DNA and the synthesis of alkali-labile modified DNAs such as oligonucleotides containing DNA lesions. This unit presents two convenient methods for the synthesis of N-unprotected deoxynucleoside 3′-phosphoramidite units and detailed procedures for automated synthesis of oligodeoxyribonucleotides from these phosphoramidite units.

Keywords:

  • N-unprotected phosphoramidite;
  • base protection;
  • activated phosphite method;
  • DNA;
  • O-selective phosphorylation;
  • alkali-labile modified DNA