74252-98-5Relevant articles and documents
Solvent-free organocatalytic asymmetric conjugate addition of thiols to α,β-unsaturated aldehydes
Ishino, Takeru,Oriyama, Takeshi
, p. 550 - 551 (2008/02/10)
A highly enantioselective asymmetric conjugate addition of thiols to α,β-unsaturated aldehydes has been achieved catalyzed by newly designed organocatalyst without solvent. Copyright
A novel tandem [4++2] cycloaddition-elimination reaction: 2-alkenyl-4,4-dimethyl-1,3-oxathianes as synthetic equivalents for α,β-unsaturated thioaldehydes
Ohsugi, Shin-Ichi,Nishide, Kiyoharu,Node, Manabu
, p. 1859 - 1871 (2007/10/03)
The first tandem cationic [4++2] polar cycloaddition-elimination reaction of 1-thia-1,3-butadienyl cations B with olefins to afford directly 3,4-dihydro-2H-thiopyrans D is described. The cations B were easily accessible by treatment of monothioacetals A, particularly the 2-alkenyl-4,4-dimethyl-1,3-oxathianes 1, with a hard Lewis acid. In this novel reaction, 2-alkenyl-4,4-dimethyl-1,3-oxathianes were utilized as synthetic equivalents for highly reactive α,β-unsaturated thioaldehydes. The effect of geminal dimethyl substituents on the oxathianes 1 and the mechanistic aspect of the reaction are considered. The reaction's asymmetric version was also investigated using a chiral oxathiane 4 derived from (-)-(1R,2R,5R)-2-(1-mercapto-1-methylethyl)-5-methylcyclohexanol. Although the enantioselectivities were moderate, the whole process can be done under odorless conditions.
Fluorophore-labeled S-nitrosothiols
Chen,Wen,Xian,Wang,Ramachandran,Tang,Schlegel,Mutus,Wang
, p. 6064 - 6073 (2007/10/03)
A series of fluorophore-labeled S-nitrosothiols were synthesized, and their fluorescence enhancements upon removal of the nitroso (NO) group were evaluated either by transnitrosation or by photolysis. It was shown-that, with a suitable alkyl linker, the fluorescence intensity of dansyl-labeled S-nitrosothiols could be enhanced up to 30-fold. The observed fluorescence enhancement was attributed to the intramolecular energy transfer from fluorophore to the SNO moiety. Ab initio density functional theory (DFT) calculations indicated that the "overlap" between the SNO moiety and the dansyl ring is favored because of their stabilizing interaction, which was in turn affected by both the length of the alkyl linker and the rigidity of the sulfonamide unit. In addition, one of the dansyl-labeled S-nitrosothiols was used to explore the kinetics of S-nitrosothiol/thiol transnitrosation and was evaluated as a fluorescence probe of S-nitrosothiol-bound NO transfer in human umbilical vein endothelial cells.
