The isolation and structure determination of two bacterial signal molecules which elicit active plant defense responses are reported. The production of these molecules by Gram-negative bacteria requires the action of avirulence gene D (avrD), cloned from Pseudomonas syringae pv. tomato. The structures of syringolide 1 (la) and syringolide 2 (lb) are determined by a combination of NMR experiments, biosynthetic arguments, molecular modeling, and X-ray crystallography. A proposed biosynthetic scheme based on the condensation of D-xylulose with a d-ketoalkanoic acid is presented. Further cyclization of the biosynthetic intermediates leads to C-glycosides with a novel tricyclic ring system. These are the first nonproteinaceous specific elicitors of a plant hypersensitive response.

The recent revision of undergraduate curricular guidelines from the American Chemical Society Committee on Professional Training (ACS-CPT) has generated interest in examining new ways of organizing course sequences both for chemistry majors and for nonmajors. A radical reconstruction of the foundation-level chemistry curriculum is presented in which content has been reorganized into three sequences: structure, reactivity, and quantitation. It is proposed that these three areas represent fundamental aspects of chemistry that cross traditional domains and allow students to more quickly appreciate the breadth of the field. An overview of these sequences in the chemistry curriculum at CSB/SJU is described.

A multiweek organic chemistry laboratory project is described that emphasizes sustainable practices in experimental design. An emphasis on student-driven development of the project is meant to mirror the independent nature of research. Students propose environmentally friendly modifications of several reactions. With instructor feedback, students search for a literature protocol for their most promising reaction. Students follow the procedure as described and also carry out a modified, greener reaction that they have designed on their own, incorporating a modest change in reaction conditions. The exercise concludes with a report focusing on comparative data analysis. This unique approach also focuses on teaching students the important research skills involved in locating, reproducing, and modifying a literature procedure.

A one-semester, introductory chemistry course is described that develops a primarily qualitative understanding of structure−property relationships. Starting from an atoms-first approach, the course examines the properties and three-dimensional structure of metallic and ionic solids before expanding into a thorough investigation of molecules. In addition to bonding, geometry, molecular orbitals, and intermolecular attractions, other structural topics are included, such as stereochemistry, conformation, and factors that influence the strength of Brønsted acids. Where appropriate, related considerations in biochemistry are highlighted. The course provides a common basis to majors and nonmajors for further study in chemistry and also serves as a platform to illustrate a variety of topics of current research interest.

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