Electron spin resonance studies of electron irradiated peptides. A single crystal of N-acetylglycine at 77 K.
Free radicals formed in single crystals of N-acetylglycine, irradiated and observed at 77 K, have been studied using ESR spectroscopy. Two different radical species were found. One radical (called ...
ESR study of L-alanine-1-13C irradiated at low temperatures.
The ESR spectra of l‐alanine‐1‐13C, x irradiated at low temperatures (T < 150°K), have been examined. The spectra have been interpreted in terms of a carboxyl radical similar to those postulated for other irradiated organic acids. From the values of the 13C hyperfine tensor it has been confirmed that the unpaired electron is essentially a 22pπ‐type electron located primarily on the carboxyl carbon and that this spin density interacts with the α proton. From the magnitude of the isotropic 13C hyperfine splitting it is found that the RCO2− structure is bent about 8° from planarity. The stable room‐temperature fragment in irradiated l‐alanine‐1‐13C exhibits essentially isotropic 13C splittings of 12.8 G.
Catalytic removal of tert-butyldimethylsilyl (TBS) ether by PVP-I
Abstract A mild, efficient and rapid protocol the deprotection of alcoholic TBDMS ethers using PVP-1 as catalyst in methanol, the procedure of deprotection of various TBDMS ethers were found to be very convenient, easy work-up, high yielding.