A room-temperature ENDOR study of X-irradiated pyridoxine hydrochloride single crystal

Abstract

Single crystals of pyridoxine hydrochloride have been irradiated and investigated at room temperature. Two radicals of different stability have been observed. Hyperfine couplings to six protons were fully characterised for each radical. The trapping sites for both radicals were found by comparison of experimental results with crystal data. The stable radical is formed by loss of hydrogen at C₆, as observed earlier in γ-irradiated pyridoxine hydrochloride. The unstable radical is formed by loss of hydrogen at C₈.