A useful method for the synthesis of 8 azido-guanosine tri- and tetraphosphate: important substrates for many enzymatic reactions.

@article{Nagesh1997AUM,
  title={A useful method for the synthesis of 8 azido-guanosine tri- and tetraphosphate: important substrates for many enzymatic reactions.},
  author={Narayana Nagesh and Dipankar Chatterji},
  journal={Journal of biochemical and biophysical methods},
  year={1997},
  volume={35 1},
  pages={61-6}
}
8-N3 GMP was synthesised from 8-BrGMP by the addition of LiN3. 8-N3GMP was then phosphorylated to N3-GDP and N3-GTP by controlled enzymatic reaction. 8-N3GDP can be converted to N3-ppGpp with crude Rel A, which phosphorylates the 3'-OH of GDP.