Microwave-assisted sequential three-component synthesis of pyrrolyl-substituted chromeno[2,3-c]isoquinolin-5-amines

[Figure not available: see fulltext.] Sequential one-pot domino reaction of homophthalonitrile, salicylaldehydes, and pyrroles in basic media under MW irradiation results in the formation of novel chromeno[2,3-c]isoquinolin-5-amines. The transformation represents a domino sequence that starts with Knoevenagel condensation, followed by two nucleophilic cyclizations, consecutively forming 2-iminochromene and 5-iminoisoquinoline cycles. Michael addition of the pyrrole unit to the chromene cycle finishes the transformation. The reaction tolerates various salicylaldehydes and pyrroles, producing target molecules with good 45–67% yields. © 2020, Springer Science+Business Media, LLC, part of Springer Nature

Glutathione

Glutathione is a simple sulfur compound composed of three amino acids and the major non-protein thiol in many organisms, including plants. The functions of glutathione are manifold but notably include redox-homeostatic buffering. Glutathione status is modulated by oxidants as well as by nutritional and other factors, and can influence protein structure and activity through changes in thiol-disulfide balance. For these reasons, glutathione is a transducer that integrates environmental information into the cellular network. While the mechanistic details of this function remain to be fully elucidated, accumulating evidence points to important roles for glutathione and glutathione-dependent proteins in phytohormone signaling and in defense against biotic stress. Work in Arabidopsis is beginning to identify the processes that govern glutathione status and that link it to signaling pathways. As well as providing an overview of the components that regulate glutathione homeostasis (synthesis, degradation, transport, and redox turnover), the present discussion considers the roles of this metabolite in physiological processes such as light signaling, cell death, and defense against microbial pathogen and herbivores