6-Thioguanosine (6-thio-G) has applications in ribozyme and siRNA research, as well as in RNA-protein interactions. The removal of the silyl protecting group without interfering with the sulfur is critical. This is removed1 cleanly by triethylamine trihydrofluoride in DMSO but t-butylammonium fluoride (TBAF) leads to degradation of the thio-nucleotide analogue and should not be used.