Asymmetric Ylide Reactions: Epoxidation, Cyclopropanation, Aziridination, Olefination, and Rearrangement

Phenolics are aromatic benzene ring compounds with one or more hydroxyl groups produced by plants mainly for protection against stress. The functions of phenolic compounds in plant physiology and interactions with biotic and abiotic environments are difficult to overestimate. Phenolics play important roles in plant development, particularly in lignin and pigment biosynthesis. They also provide structural integrity and scaffolding support to plants. Importantly, phenolic phytoalexins, secreted by wounded or otherwise perturbed plants, repel or kill many microorganisms, and some pathogens can counteract or nullify these defences or even subvert them to their own advantage. In this review, we discuss the roles of phenolics in the interactions of plants with Agrobacterium and Rhizobium.

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The roles of plant phenolics in defence and communication during Agrobacterium and Rhizobium infection

"Hairy root" systems, obtained by transforming plant tissues with the "natural genetic engineer" Agrobacterium rhizogenes, have been known for more than three decades. To date, hairy root cultures have been obtained from more than 100 plant species, including several endangered medicinal plants, affording opportunities to produce important phytochemicals and proteins in eco-friendly conditions. Diverse strategies can be applied to improve the yields of desired metabolites and to produce recombinant proteins. Furthermore, recent advances in bioreactor design and construction allow hairy root-based technologies to be scaled up while maintaining their biosynthetic potential. This review highlights recent progress in the field and outlines future prospects for exploiting the potential utility of hairy root cultures as "chemical factories" for producing bioactive substances.

Hairy root type plant in vitro systems as sources of bioactive substances

Visible light photoredox catalysis has emerged as a powerful technique for chemoselective activation of chemical bonds under mild reaction conditions. Here, visible-light-mediated conversion of alcohols to the corresponding bromides and iodides is described. The reaction proceeds in good yield with exceptional functional group tolerance, and minimizes the formation of stoichiometric waste.

Visible-light-mediated conversion of alcohols to halides

Host recognition and macromolecular transfer of virulencemediating effectors represent critical steps in the successful transformation of plant cells by Agrobacterium tumefaciens. This review focuses on bacterial and plant-encoded components that interact to mediate these two processes. First, we examine the means by which Agrobacterium recognizes the host, via both diffusible plant-derived chemicals and cell-cell contact, with emphasis on the mechanisms by which multiple host signals are recognized and activate the virulence process. Second, we characterize the recognition and transfer of protein and protein-DNA complexes through the bacterial and plant cell membrane and wall barriers, emphasizing the central role of a type IV secretion system—the VirB complex—in this process.

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Agrobacterium tumefaciens and Plant Cell Interactions and Activities Required for Interkingdom Macromolecular Transfer

Effects of phenolic compounds on Agrobacterium vir genes and gene transfer induction*/a plausible molecular mechanism of phenol binding protein activation

Daniel Beaupère

Papers

Effects of phenolic compounds on Agrobacterium vir genes and gene transfer induction*/a plausible molecular mechanism of phenol binding protein activation

A new and direct access to glycono-1,4-lactones from glycopyranoses by regioselective oxidation and subsequent ring restriction

One-pot stereoselective synthesis of glycosyl azides via 1,2-cyclic sulfite

A novel stereospecific synthesis of glycosyl cyanides from 1,2-O-sulfinyl derivatives.

Direct Regioselective Chlorination of Unprotected Hexitols and Pentitols by Viehe's Salt