Identification of 1,4-Benzoxazin-3-ones in Maize Extracts by Gas-Liquid Chromatography and Mass Spectrometry

Publisher Website
Google Scholar
Abstract
GLC-mass spectrometry (GLC-MS) was used for the separation, detection and identification of 1,4-benzoxazin-3-ones (hydroxamic acids and lactams) and benzoxazolinones found in maize (Zea mays L.) extracts. Compounds of interest were partitioned into ethyl acetate from aqueous maize seedling extracts. For analysis by GLC-MS, trimethylsilyl derivatives were prepared, chromatographed on a column of 3% OV-1, and detected in the mass spectrometer. Mass spectra were obtained for all peaks present in extracts of 4 maize lines. A data comparison system was developed for relating unidentified spectra to the spectra of the reference compounds. Based on spectral comparisons, 3 hydroxamic acids (2,4-dihydroxy-2H-1, 4-benzoxazin-3(4H)-one; 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H) ones; and 2,4-dihydroxy-7,8-dimethoxy-2H-1,4-benzoxazin-3(4H)-one), 3 lactams (2-hydroxy-2H-1,4-benzoxazin-3(4H)-one; 2.7-dihydroxy-2H-1,4-benzoxazin-3(4H)-one; and 2-hydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one), 1 benzoxazolinone (6-methoxybenzoxazolinone) and 2 organic acids (malic and aconitic) were identified in the extracts. In addition, 1 other hydroxamic acid and 1 other related compound were tentatively identified based on mass spectral evidence.