18903-30-5Relevant articles and documents
Chemo-Enzymatic Synthesis of Pyrazines and Pyrroles
Xu, Jin,Green, Anthony P.,Turner, Nicholas J.
supporting information, p. 16760 - 16763 (2018/11/27)
Herein we report the biocatalytic synthesis of substituted pyrazines and pyrroles using a transaminase (ATA) to mediate the key amination step of the ketone precursors. Treatment of α-diketones with ATA-113 in the presence of a suitable amine donor yielded the corresponding α-amino ketones which underwent oxidative dimerization to the pyrazines. Selective amination of α-diketones in the presence of β-keto esters afforded substituted pyrroles in a biocatalytic equivalent of the classical Knorr pyrrole synthesis. Finally we have shown that pyrroles can be prepared by internal amine transfer catalyzed by a transaminase in which no external amine donor is required.
Alkylations and hydroxymethylations of pyrazines via green minisci-type reactions
Bohman, Bjorn,Berntsson, Benjamin,Dixon, Ruby C. M.,Stewart, Craig D.,Barrow, Russell A.
supporting information, p. 2787 - 2789 (2014/06/23)
A new general methodology utilizing Minisci-type chemistry has been developed that cleanly and efficiently prepares alkyl- and (hydroxymethyl) pyrazines. The new methods eliminate toxic catalysts and halogenated solvents, providing a greatly improved route to these natural products which are prevalent in many natural systems as bacterial volatiles, plant volatiles, and insect pheromones.
Electrolytic Oxidation of Ketones in Ammoniacal Methanol in the Presence of Catalytic Amounts of KI
Chiba, Toshiro,Sakagami, Hirotoshi,Murata, Miki,Okimoto, Mitsuhiro
, p. 6764 - 6770 (2007/10/03)
The indirect electrooxidation of ketones in ammoniacal methanol using iodide ion as a mediator afforded 2,2-dialkyl-2,5-dihydro-1H-imidazoles 3 via an oxidative cyclocoupling of ketimine intermediates formed from ketones and ammonia.The treatment of 3 with dilute HCl gave α-amino ketone hydrochlorides 4 and the parent ketones in good yields.A similar electrooxidation of 3 resulted in the formation of the corresponding 2H-imidazoles 6, which were hydrolyzed to α-diketones and the parent ketones.The same products 6 could also conveniently be obtained by chemical oxidation of 3 with aqueous NaOCl.
INTRODUCTION OF THE METHYL GROUP INTO THE PYRAZINE RING
Ohta, Akihiro,Inoue, Akira,Watanabe, Tokuhiro
, p. 2317 - 2321 (2007/10/02)
By the coupling reaction of mono- and dichloropyrazines with trimethylaluminum in the presence of a palladium catalyst, the corresponding mono- and dimethylpyrazines were prepared in excellent yields.
