588716-65-8Relevant articles and documents
Completion of the spectroscopical data for the synthesis of DIMBOA
Handler, Norbert,Erker, Thomas
, p. 95 - 100 (2007/10/03)
Cyclic hydroxamic acids like 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin- 3(4H)-one (DIMBOA) and 2,4-dihydroxy-2H-1,4-benzoxazin-3(4H)-one (DIBOA) are found in several plants playing an important role in the defense-system of plants against a variety of enemies. To investigate new mechanism and effects we synthesized the molecules using known synthetic pathways. Since the chemical data of DIMBOA are not complete or even false, we decided to publish the missing ones in this journal. O?sterreichische Apotheker-Verlagsgesellschaft m. b. H.
Novel compounds for use in weight loss and appetite suppression in humans
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, (2008/06/13)
Phenolic compounds with a phenolic molecule to which are covalently linked an oxygen-containing group, a nitrogen or another oxygen containing group, and a C1-C4 alkoxy group, obtainable from monocotyledonous plants, or by chemical synthesis, have been found to act as weight loss agents, appetite suppressants, mood enhancers and adjunctive therapy for arthritis, sleep apnea, fibromyalgia, diabetes and hyperglycemia. Additional chemical compounds of the present invention may include benzoxazinoids-cyclic hydroxyamic acids, lactams, and corresponding glucosides, which may serve as precursors to phenolic compounds. The phenolic compounds and precursors of phenolic compounds of the present invention, at concentrations suitable for human therapeutic use, may be obtained from monocotyledonous plants such as corn in their early growth states which are timely harvested for optimum yield.
An improved synthesis of cyclic hydroxamic acids from Gramineae
Tays, Kevin,Atkinson, Jeffrey
, p. 903 - 912 (2007/10/03)
The boron trichloride sensitive methoxymethyl (MOM) protecting group has been used to efficiently synthesize polymethoxylated derivatives of the benzoxazinone family of cyclic hydroxamic acids. The MOM group allows the unveiling of the hemiacetal at C-2 of these compounds without demethylating ring methoxy substituents, resulting in greatly increased yields.
NON-INDUCED CYCLIC HYDROXAMIC ACIDS IN WHEAT DURING JUVENILE STAGE OF GROWTH
Nakagawa, Eri,Amano, Takashi,Hirai, Nobuhiro,Iwamura, Hajime
, p. 1349 - 1354 (2007/10/02)
2,4-Dihydroxy-1,4-benzoxazine -3-one glucoside (DIBOA-G) and its methoxy analogue, 2,4-dihydroxy-7-methoxy-1,4-benzoxazine-3-one glucoside (DIMBOA-G), were present in germinating wheat (Triticum aestivum); the corresponding aglycones, DIBOA and DIMBOA, appeared soon after germination.The amounts of these compounds reached a maximum 12-48 hours after germination, and then decreased to undetectable levels as the plants began autotropic growth.The time of their appearance was little affected by using seeds either sterilized or non-sterilized, by infection with pathogens and wounding with a razor blade.The concentration of DIBOA was found to be 0.2-0.3 nmol mg-1 fr. wt (0.2-0.3 nM if the density of plant tissue is assumed to be uniform and unity) and that of DIMBOA was 0.7-1.0 nmol mg-1 (0.7-1.0 nM).The aglycones retarded the germ tube growth of species of fungi at 0.3 mM.These observations suggest that the appearance of benzoxazinones is as defence compounds in the juvenile stage of growth. Anthranilic acid was incorporated into DIBOA-G and DIMBOA-G when administered to embryos isolated from pre-emerging seeds, showing that the series of compounds are generated by de novo synthesis. - Key words: Triticum aestivum; Gramineae; seedlings; hydroxamic acids; benzoxazinones; biosynthesis.
Chemical Studies on 2,4-Dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one in Connection with 6-Methoxy-2-benzoxazoline, an Auxin-inhibiting Substance of Zea mays L.
Kosemura, Seiji,Yamamura, Shosuke,Anai, Toyoaki,Hasegawa, Koji
, p. 8221 - 8224 (2007/10/02)
Some chemical studies on 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA, 1) and related compounds from Zea mays L. have been carried out, where DIMBOA (1) has been very rapidly converted into 6-methoxy-2-benzoxazolinone (MBOA, 2), an auxin-inhibiting substance of maize, in the presence of acetic anhydride at room temperature.Therefore, such an enzymatic acylation of N-OH group of DIMBOA (1) as in vitro presumably plays an important role on phototropism.
α-Hydroxylation of Cyclic Hydroxamic Acids by Peroxide Oxidation: A Novel Approach to Allelochemicals from Graminae
Hartenstein, Holger,Sicker, Dieter
, p. 4335 - 4338 (2007/10/02)
Naturally occurring hemiacetals DIBOA and DIMBOA were synthesized by the first α-hydroxylation of N-hydroxylactams via m-chloroperbenzoic acid oxidation of corresponding cyclosilyl enol ethers.
A new general approach to the 2-hydroxy-2H-1,4-benzoxazin-3(4H)-one skeleton via diisobutylaluminum hydride reduction of 2,3-dioxo-1,4-benzoxazines
Sicker,Hartenstein
, p. 771 - 772 (2007/10/02)
A series of naturally occurring hemiacetals 2a-d was synthesized by the chemoselective diisobutylaluminum hydride reduction of 2,3-dioxo-4H-1,4-benzoxazines 1a,b and their N-hydroxy derivatives 1c,d precursors. The procedure described represents a new general approach to the 2-hydroxy-2H-1,4-benzoxazin-3(4H)-one skeleton giving rise to the bioactive natural hydroxamic acids 2,4-dihydroxy-2H-1,4-benzoxazin-3(4H)-one (2c) and 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (2d) in only three steps starting from nitrophenols.
Analogues of the Cyclic Hydroxamic Acid 2,4-Dihydroxy-7-methoxy-2H-1,4-benzoxazin-3-one: Decomposition to Benzoxazolinones and Reaction with β-Mercaptoethanol
Atkinson, Jeffrey,Morand, Peter,Arnason, John T.,Niemeyer, Hermann M.,Bravo, Hector R.
, p. 1788 - 1800 (2007/10/02)
Analogues of the aglucones of naturally occurring cyclic hydroxamic acids (2,4-dihydroxy-1,4-benzoxazin-3-ones) from Gramineae (Poaceae) have been synthesized by the reductive cyclization of the ring-substituted methyl α-(o-nitrophenoxy)-α-methoxyacetates, followed by demethylation of the C-2 methoxy group with BBr3 or BCl3 to reveal the 2-hydroxy group.A structure-activity series was produced by varying the substituent at C-7 on the aromatic ring .The pKa values for the hydroxamic acid and the phenol moieties were determined for each member of the C-7 series.They correlated well with ? in a linear free energy relationship (LFER) yielding values of ρ = 0.71 (with ?p) for pKa1 (the hydroxamic acid) and ρ = 1.6 (with ρm) for pKa2 (the phenol).A LFER also existed between the rate constants for the unimolecular decomposition of these hydroxamic acids to benzoxazolinones and ?+ (ρ = -1.1).The rates of hydroxamic acid reduction to lactams by β-mercaptoethanol were also investigated.It was found that only compounds with electron-rich aromatic rings and specifically an oxa functionality para to the hydroxamic acid nitrogen atom (compounds 1 and 3 - 5) had measurable rates of reduction. 1H NMR spectra recorded during this reaction in D2O buffers (pD 9), however, showed that compounds 1, 2, 6 - 9 (the only ones investigated) formed a hemithioacetal at C-2 even though only 1 has a measurable rate of reduction by the same thiol.The remarkable rate enhancement provided by an oxa functionality suggests that reduction occurs by direct attack of thiolate on the hydroxamic nitrogen of a resonance-stabilized ion pair.
