Palladium-catalyzed reactions of allenes.

Plants defend themselves from pathogen infection through a wide variety of mechanisms that can be either local or systemic, constitutive or inducible (32, 70, 108, 109). In most cases, the extent to which these various systems affect disease progression is poorly understood, and is an area of extensive biochem­ ical and genetic research. One particular inducible systemic response, known as systemic acquired resistance (SAR), has become a subject of increasing inquiry. SAR is a b road, physiological immunity that results from infection with a necrogenic pathogen. In addition, certain natural and synthetic chemical compounds can trigger similar plant responses. This chapter reviews the liter­ ature on chemicals that apparently act by stimulating the natural defense response in the plant. To put this information in context, we first describe what is known at present about the occurrence of SAR in various species, and our current concept of pathogen-induced SAR. Other recent reviews related to biologically induced SAR and signal transduction complement our discussion (40, 73, 84, 99, 108)

Induction of Systemic Acquired Disease Resistance in Plants by Chemicals

The prediction of structure at the atomic level is one of the most fundamental challenges in condensed matter science. Here we survey the current status of the field and consider recent developments in methodology, paying particular attention to approaches for surveying energy landscapes. We illustrate the current state of the art in this field with topical applications to inorganic, especially microporous solids, and to molecular crystals; we also look at applications to nanoparticulate structures. Finally, we consider future directions and challenges in the field.

Crystal structure prediction from first principles

Photochemical reactions contribute in a significant way to the existing repertoire of carbon-carbon bond-forming reactions by allowing access to exceptional molecular structures that cannot be obtained by conventional means. In this Review, the most important photochemical transformations that have been employed in natural product synthesis are presented. Selected total syntheses are discussed as examples, with particular attention given to the photochemical key step and its stereoselectivity. The structural relationship between the photochemically generated molecule and the natural product is shown, and, where necessary, the consecutive reactions in the synthesis are illustrated and classified.

Photochemical reactions as key steps in natural product synthesis

Impact of phyto-oxylipins in plant defense.

Momilactones, Growth inhibitors from rice, Oryza sativa L

Growth and germination inhibitors in rice husks

In addition to the previously described epoxy fatty acids, five hydroxy fatty acids were characterized as self defensive substances produced in the rice plant against rice blast disease.

Tadahiro Kato

Papers

Momilactones, Growth inhibitors from rice, Oryza sativa L

Growth and germination inhibitors in rice husks

Unsaturated hydroxy fatty acids, the self defensive substances in rice plant against rice blast disease

Self defensive substances in rice plant against rice blast disease

Structure and synthesis of unsaturaded trihydroxy c18 fatty