Isolation and Spectral Analysis of Naturally Occurring Thiarubrine A

• Juan Reyes ^[1] ; Melita Morton ^[1] ; Gary G. Hoffman ^[1] ; Kevin E. O'Shea ^[1] ; Kelsey Downum ^[1]
  1. [1] Florida International University

     Florida International University

     Estados Unidos

     
• Localización: Journal of chemical education, ISSN 0021-9584, Vol. 78, Nº 6, 2001, pág. 781
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • We have designed an experiment in which students isolate and characterize thiarubrine A, a pseudo-antiaromatic 1,2-dithia-3,5-cyclohexadiene derivative. Thiarubrines are an important class of compounds which have recently received attention because of their unusual reactivity, unique biological activity, and potential medicinal applications. They possess a distinctive red color and structure features that are particularly useful for demonstrating UV-vis, NMR, and IR spectral analyses. A crude mixture containing thiarubrine A is obtained by methanol (liquid-solid) extraction of the roots of short ragweed, Ambrosia artemisiifolia. Alternatively, these compounds can be isolated from numerous taxa within the family Asteraceae. Thiarubrine A possesses alkyl, alkenyl, and alkynyl functionality, which is useful in illustrating the utility of IR and NMR in the characterization of natural products. The long wavelength UV-vis absorption band of thiarubrine is indication of the nonplanarity of dithiin ring and provides an excellent opportunity to discuss the concepts of aromaticity, conjugation, and molecular orbital theory.