82161-35-1Relevant academic research and scientific papers
S-pixyl analogues as photocleavable protecting groups for nucleosides
Coleman, Michael P.,Boyd, Mary K.
, p. 7641 - 7648 (2007/10/03)
Several analogues of the 9-phenylthioxanthyl (S-pixyl) photocleavable protecting group have been synthesized, containing substituents on the 9-aryl ring and on the thioxanthyl backbone. Each analogue protected the 5′-hydroxy moiety of thymidine in good to excellent yield. The protected substrates were deprotected in 1:1 water: acetonitrile with irradiation at 300 nm, resulting in recovered thymidine in excellent yield, except for the nitro-substituted analogues which gave substantially lower yields. Substrates with 2,7-dibromo or 3-methoxy substitution on the thioxanthyl backbone were also deprotected efficiently with irradiation at 350 nm. Shorter irradiation times were observed in the less nucleophilic solvent mixture of 1:9 trifluoroethanol: acetonitrile, with no formation of secondary photooxidation products. Photodeprotection with high yields was also achieved in the absence of solvent, with no secondary photoproducts.
The S-pixyl group: An efficient photocleavable protecting group for the 5' hydroxy function of deoxyribonucleosides
Coleman, Michael P.,Boyd, Mary K.
, p. 7911 - 7915 (2007/10/03)
The 9-phenylthioxanthyl (S-pixyl or S-Px) group has been investigated as a photocleavable protecting group for primary alcohols, and specifically as a 5' hydroxy protecting group for deoxyribonucleosides. Several alcohols, including the four nucleosides with protected exocyclic amino functions, were protected in very good to excellent yield by treatment of 9-chloro-9-phenylthioxanthene 3 in dry pyridine to reveal the derivatized compounds. Irradiation of the protected substrates in neutral, aqueous solution regenerated the starting alcohols in excellent yield.
