New esters from the essential oil of dry flowers of elder (Sambucus nigra L.).

BACKGROUND: Elder (Sambucus nigra L.) has relevance for the food, fragrance and pharmaceutical industries. Flowers of this species emit a very pleasant scent; for processing purposes, inflorescences are either collected from the wild or harvested from a cultivated crop. The study of elderflower‐derived volatiles bears both phytochemical and commercial importance. RESULTS: Three samples of dry elderflower essential oil obtained from laboratory‐scale hydrodistillations were analyzed. By use of gas chromatography‐mass spectrometry, synthesis and NMR studies of chromatographic fractions of a distillation water extract prepared in a semi‐industrial scale steam distillation, 252 constituents of the oil were identified; 115 compounds were not previously reported as elderflower volatiles, seven of which were new natural esters. Particularly interesting were those of isosenecioic (3‐methylbut‐3‐enoic) acid because these were never before found in the plant kingdom. CONCLUSION: With these identifications, the known essential oil constituents accounted for 89.0–93.0% of the analyzed samples. Although the number of known S. nigra flower‐derived volatiles is now quite high, further research (both analytical and olfactory) is needed to unveil all of the relevant contributions to the unique odor of elderflowers. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]