78300-37-5Relevant academic research and scientific papers
Monoradical Rearrangements of the 1,4-Biradicals Involved in Norrish Type II Photoreactions
Wagner, Peter J.,Liu, Kou-Chang,Noguchi, Y.
, p. 3837 - 3841 (1981)
The photochemistry of α-allylbutyrophenone (α-AB) and that of γ-cyclopropylbutyrophenone (γ-CB) both reveal that the 1,4-biradicals generated by triplet-state γ-hydrogen abstraction undergo typical radical rearrangements in competition with their more normal type II reactions.From α-AB, 2-phenyl-2-norbornanol is formed in 1/24th the combined yield of 1-phenyl-4-penten-1-one and 1-phenyl-2-allylcyclobutanol.Its formation is explained by a 5-hexenyl-to-cyclopentylmethyl rearrangement of the 1,4-biradical, with a rate constant of 5 x 105 s-1.From γ-CB, 1-phenyl-4-hepten-1-one and 1-phenyl-4-cycloheptenol together are formed in double the yield of acetophenone.Their formation is explained by a cyclopropylcarbinyl-to-allylcarbinyl rearrangement of the 1,4-biradical, with a rate constant of 2 x 107 s-1.In both cases, the rearrangement percentages are what would be predicted if the biradicals have the same 35 - 50-ns lifetime measured for other ketones and if they rearrange with the same rate constants characteristic of monoradicals.Triplet γ-CB decays only 1.5 times faster than triplet γ-isopropylbutyrophenone, indicating that there is at most a small enhancement of the γ-hydrogen abstraction rate by cyclopropyl cojugation.Triplet α-AB decays 100 times faster than triplet butyrophenone, 99percent representing internal quenching by the β-vinyl group ( k = 8 x 108 s-1).Bicyclic oxetanes are formed in quantum yields of only 0.01.No oxetanes were isolated, only rearranged unsaturated alcohols and aldehydes.
COMPLEMENT MODULATORS AND RELATED METHODS
-
, (2020/10/20)
The present disclosure presents compounds and compositions that interact with complement components. Some compounds inhibit complement activity. Included are small molecule compounds and compositions that function as C5 inhibitor compounds. Methods for inhibiting complement activity and methods of treating complement-related indications with the C5 inhibitor compounds and compositions are provided.
