Advances in the synthesis of modified NTPs

Nucleoside triphosphates (NTPs) are building blocks of nucleic acids and play an important role in molecular biology, like PCR and diagnostics, as well as pharmaceutical applications. So far, the golden standard to produce modified NTPs are chemical syntheses. Chemical production routes show limitations due to a low regio- and stereo-selectivity and the need for protection groups. Therefore, they often lead to low yields and are expensive and time consuming. As an alternative, different enzymatic synthesis pathways have been developed. They offer the advantage of high stereo- and regioselectivity which leads to greatly reduced reaction and purification effort as well as often high product yields. While chemical synthesis routes for NTPs have been discussed extensively a comparison to enzymatic methods in terms of yield, production steps and production times is lacking. The aim of this review is to describe the relevance of NTP analogs in a number of applications and to compare described chemical and enzymatic methods for NTP synthesis. AraCTP was chosen as an example to demonstrate advantages and disadvantages of the different approaches.