2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one

Survival after 24 h and the number of aphids feeding were determined at 4 mM compound in the diet. Reproductive index (number of nymphs/ average number of adults) was determined at 0.15 mM compound in the diet. Values are the average of three samples of ten aphids each. For reproduction studies five samples were used. Standard errors were always less than 10%. DIMBOA 2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one. 

Oikawa, A., Ebisui, K., Sue, M., Ishihara, A., and Iwamura, H. 1999. Purification and characterization of a p-glucosidase specific for 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) glucoside in maize. Z. Naturforsch. C Biosci. 54, 181-185... 

Wu, H., Haig, T., Pratley, J., Lemerle, D., and An, M. 1999. Simultaneous determination of phenolic acids and 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one in wheat (Triticum aestivum L.) by gas chromatography-tandem mass spectrometry. J. Chromatogr. A 864, 315-321... 

DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) is a cyclic hydroxamic acid produced by members of the Gramineae as a defense against herbivores or microbial pathogens [60]. Maize CYP71C1 catalyzes the hydroxylation of indolin-2-one at the 3-position... 

APCI has become a popular ionization source for applications of coupled HPLC-MS. Figure 1.33 shows an example of an application of HPLC-APCI coupling [79]. It shows the analysis obtained from extracts of maize plants. Six compounds are identified by mass spectrometry. These compounds have been identified as glucoconjugated DIMBOA (2,4-dihydroxy-7-methoxy-l,4-benzoxazin-3-one) and similar molecules that differ by the number of methoxy groups in the benzene ring and/or by the N-O methylation of the hydroxamate function. This example clearly shows the influence of the analyte on the type of observed molecular species. Indeed, the presence of an acidic group in the compound from peak 1 allows mainly the detection of deprotonated molecular ions, whereas the compound from peak 4 does not contain an acid group and thus leads only to the formation of adduct ions. 

Benzoxazinoids Rye, wheat, com (Zea mays) 2,4-Dihydroxy-7-methoxy-7.H-1,4-benzoxazin-3(4 -one [76]... 

A series of hydroxamic acid derivatives with 4-hydroxy-l,4-benzoxazin-3-one structures occur in a number of cereal grain species (Poaceae or Gramineae) (Fig. 7.8) (Niemeyer, 1988). These compounds usually occur in plants as the 2-3-(9-D-glucosides enzymes that hydrolyze the compounds usually co-occur. DIBOA [2,4-dihydroxy-1,4(2H)-benzoxazin-3-one] (22) is the major compound in rye and DIMBOA [2,4-dihydroxy-7-methoxy-1,4(2H)-benzoaxa-... 

Hartenstein, H., Lippmann, T. and Sicker, D. 1992. An efficient procedure for the isolation of pure 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA) from maize. Ind. J. Heterocycl. Chem. 2, 75-76... 

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