SYNTHESIS OF REVERSIBLE NUCLEOTIDE TERMINATORS BY IN-SITU THIO-ALKYL GROUP TRANSFER FOR USE IN DNA SEQUENCING BY SYNTHESIS

The invention is directed to a method for production of a deoxynucleotide triphosphate according to general formula (7)wherein B is a nucleobase and R is an alkyl group having 1 to 4 carbon atoms and n is an integer from 1 to 10 by reaction of reaction precursor of compound 6wherein R1, R2 and R3 are independently H, O-Alkyl with alkyl residues having 1 to 4 carbon atoms or halogen and n is an integer from 1 to 10 with dialkyl(alkylthio)sulfonium salt (8B)wherein R4, R5 R6 are independently alkyl residues having 1 to 4 carbon atoms and X is selected from the group consisting of BF4−, F−, Cl−, Br−, I−, SO42−, SO32− in aqueous solution having a pH between 3 and 7.