The best of both worlds: The configurational assignment of a natural product—chivosazole A (1) isolated from myxobacteria—has been achieved for the first time through the combination of structure elucidation and genetic analysis. This was achieved by chemical degradation, analysis of the NMR data in combination with computer‐aided conformation analysis, and assignment of the amino acid sequence.

The first cyclopentadienylalkylphosphane nickel chelate complexes are reported. The anionic ligand obtained by reaction of spiro[2.4]hepta-4,6-diene with lithium di-tert-butylphosphide was treated with NiCl2 to yield [eta(5):kappa(1)-(di-tert-butylphosphanylethyl)cyclopentadienyl]chloronickel(II). From this complex, some acetonitrile-stabilized cationic complexes were obtained by reaction with the respective silver salts in acetonitrile. Methyl- and alkynylnickel chelates were prepared by reaction of the chloronickel complex with methyllithium and by copper-mediated coupling with terminal alkynes, respectively. Some of the complexes prepared were investigated by X-ray crystallography or cyclic voltammetry. The alkynylnickel chelates undergo cycloaddition reactions with ethoxycarbonylisothiocyanate or tetracyanoethylene, and the cyclobutenes obtained undergo ring opening to the corresponding dienes. The study includes an NMR spectroscopic investigation of the two conformers of one of these dienes.

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Submerged microbial cultures were screened for their potential to oxifunctionalize alpha-farnesene. The major oxidation product in all transforming cultures, 3,7,11-trimethyldodeca-1,3(E),5(E)10-tetraen-7-ol, showed a pleasant citrus-like odor and peak concentrations of 170 mg L-1. An Aspergillus niger isolate from mango generated another two terpene alcohols identified as diastereomeric menth-1-en-3-[2-methyl-1,3-butadienyl]-8-ol, a new natural compound with an apricot-like odor. The regiospecifity of the oxygen attack with concurrent lack of stereoselectivity suggested that the initial step of the bioconversion resembled the chemical autoxidation starting with the generation of an intermediate resonance-stabilized carbon-centered radical or carbocation.