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A library of 600 taxonomically diverse Panamanian plant extracts was screened for fungicidal, insecticidal, and herbicidal activities. A total of 19 active extracts were submitted to HPLC-based activity profiling, and extracts of Bocconia frutescens, Miconia affinis, Myrcia splendens, Combretum aff. laxum, and Erythroxylum macrophyllum were selected for the isolation of compounds. Chelerythrine (2), macarpine (3), dihydrosanguinarine (5), and arjunolic acid (8) showed moderate-to-good fungicidal activity. Myricetin-3-O-(6''-O-galloyl)-β-galactopyranoside (13) showed moderate insecticidal activity, but no compound with herbicidal activity was identified.

A broad range of halogenated 2,2'-biphenols was tested for applicability as crop protection agents. The activity of these compounds toward four typical pest plants was observed after application by spraying of diluted solutions. Despite their rather simple structure, it was found that the studied compounds reveal a surprisingly high herbicidal impact. To gain a better understanding of the structure-activity relationship, specific sites of the molecule were chemically modified and the core structures thus gradually changed. The influence of the substitution pattern on the herbicidal properties is discussed, and conclusions on the active site of the biphenol structure are drawn. It was observed that type and position of the halogen substituents have a significant influence on the activity of the core structure. The hydroxy functionalities play a crucial role for the effectiveness of the tested compounds. Because the blocking of the hydroxy moiety leads to dramatically deteriorated performances, the presence of these functionalities on the aromatic ring seems to be indispensable.

Enantioselective organo-SOMO catalysis has, in the last two years, been the subject of considerable development and exploration. A number of new and unique transformations have been reported, such as alpha-allylation, alpha-oxyamination, alpha-enolation, and alpha-vinylation of aldehydes. Herein, we report a modification of this activation mode that involves the intramolecular Friedel-Crafts-type alpha-arylation of aldehydes carrying electron-donating groups on their aromatic nucleus and its application to the total synthesis of demethyl calamenene, a potent cytotoxic agent against human adenocarcinoma A 549.

Using reactive trialkylaluminium reagents for the 1,2-addition on acetophenone- and benzophenone-derived ketimines, alpha-trisubstituted amines were obtained in excellent yields up to 99%.