Photo-CIDNP [chemically induced dynamic nuclear polarization] from carbon-sulfur cleavage of alkyl disulfides

Mechanism and Kinetics of Photoisomerization of a Cyclic Disulfide,trans-4,5-Dihydroxy-1,2-dithiacyclohexane

“…In addition, several authors have obtained evidence for both C-S and S-S cleavage of disulfides through interaction with triplet excited states. [39][40][41][42] On the basis of these observations, the homolytic cleavage of disulfides does not necessarily require direct exposure to light. For example, triplet excited ketones form during the thermal decomposition of dioxetanes, which are prominent biological oxidation products.…”

Novel condensation of 2,3-epoxybutanal with 2-aminopyridine and 2-aminopyrazine. Synthesis and stability of 3-(1-hydroxyethyl)imidazo[1,2-a]azines

“…X-ray Structure of 3-(l-Oxoethyl)imidazo[l,2-a]pyrazine (7). Crystallization of 7 from dilute solution in toluene gave suitable crystals having symmetry Pbca with a = 6.686 (1) A, b = 9.37 (2), and c = 23.906 (7).…”

“…X-ray Structure of 3-(l-Oxoethyl)imidazo[l,2-a]pyrazine (7). Crystallization of 7 from dilute solution in toluene gave suitable crystals having symmetry Pbca with a = 6.686 (1) A, b = 9.37 (2), and c = 23.906 (7). The structure was solved by using standard direct methods and refined by using the full-matrix least-squares method.…”

“…3-(l-Oxoethyl)imidazo[l,2-a]pyrazine (7). 3-(l-Hydroxyethyl)imidazo[l,2-o]pyrazine (1.47 g, 900 mmol) and manganese dioxide (7.2 g) were stirred in 50 mL of acetone for 1 week at room temperature.…”

Structure du chloro-3 méthyl-2 4H-pyrazino[1,2-a]pyrimidinone-4

“…L'&ude cristalline confirme la structure de la chloro-3 m&hyl-2 4H-pyrazino[1,2-a]pyrimidinone-4 proposse par Abignente et al (1985) fi la suite d'une &ude RMN de 1H et 13C. La pseudo isotypie de ce compos~ avec l'(oxo-1 &hyl)-3 imidazo[1,2-a]pyrazine (Pbca, a = 6,69, b = 9,37, c = 23,91 A) (Rosenfeld, Lawler & Ward, 1972) n'est pas indicatrice d'une analogie mol~culaire totale.…”