7,10,12-trihydroxy-8 , production

Strain ALA2 showed the highest relative in vivo activity for the bioconversion linoleic acid to trihydroxy-9(Z)-octadecenoic acid per Table 16.1 (Hosokawa et al., 2003c). The relative activities for a- and y-linolenic acids toward trihydroxy products were lower than that of linoleic acid, though still relatively... 

Pellotine and Anhalonidine. The A -acetyl derivative of mezcaline (I NHj— NHAc), on treatment with phosphoric oxide, yields 6 7 8-trimethoxy-l-methyl-3 4-dihydrowoquinoline (picrate, m.p. 181-2°), which, on successive catalytic hydrogenation and treatment with methyl sulphate, yields 6 7 8-trimethoxy-l 2-dimethyl-l 2 3 4-tetrahydro-isoquinoline identical with 0-methylpellotine (picrate, m.p. 167-8°), whence it appears that pellotine must be a dimethyl ether of 6 7 8-trihydroxy-1 2-dimethyl-l 2 3 4-tetrahydrowoquinoline. Pellotine and anhalonidine on complete methylation yield the same product, and as anahalonidine is a secondary base and differs from pellotine by containing —CHj less, it must be a dimethyl ether of 6 7 8-trihydroxy-l-methyl-1 2 3 4-tetrahydrowoquinoline, and pellotine should be A -methyl-anahalonidine. 

The enol lactone (12.7 g) is added to 157 ml of 0.5 M perbenzoic acid in benzene and allowed to stand at 25° for 140 hr. The solution is cooled to 15° and 15% sodium bisulfite solution is added to neutralize the excess peracid. The organic layer is separated and washed with saturated sodium bicarbonate solution and water. The benzene solution is dried over anhydrous sodium sulfate, filtered and concentrated to 30 ml. The product is crystallized by adding 80 ml of petroleum ether, filtered and washed with petroleum ether to yield 12.8 g (98%) of 3a,20,23-trihydroxy-16a-methyl-17(20)-oxido-ll-oxo-21-norchol-22-enoic acid-24(20)-lactone 3,23-diacetate mp 225-227°. 

The isolation of two tautomers of 2,3,4-trihydroxyquinoline has been reported but one was later identified as the isomeric 1,2,4-trihydroxy compound 47. The fact that 2,3,4-trihydroxyquinoline is oxidized more slowly than its A -methyl derivative was considered to show that it existed in an oxo form. The product resulting from... 

The excess of N-chlorosuccinimide is destroyed by the addition of about 15 drops of allyl alcohol and 180 ml of water is then added with stirring. This mixture is held at 0°C for about one hour. The precipitated 16/3-methyl-1,4-pregnadiene-9o-chloro-11/3,17o,21-triol-3,20-dione-21-acetate is recovered by filtration. A solution of 250 mg of the chlorohydrin in 5 ml of 0.25N perchloric acid in methanol is stirred for about 18 hours at room temperature to produce 16/3-methyl-9o-chloro-11/3,17o,21-trihydroxy-1,4-pregnadiene-3,20-dione which is recovered by adding water to the reaction mixture and allowing the product to crystallize. Propionic anhydride is then used to convert this material to the dipropionate. 

The crude product obtained above is dried in high vacuum and then dissolved in 4 cc of pyridine. About 3 cc of acetic anhydride is added. The mixture is then heated on the steam bath for about 15 minutes and then evaporated to dryness in vacuo. About 20 cc of water is added. The product is then extracted into 150 cc of ethyl acetate, washed with saturated sodium bicarbonate solution and water, and dried over sodium sulfate. The solvent is removed in vacuo to give a residue which is crystallized from ethyl acetate-benzene to yield about 250 mg of 11/3,17a,21-trihydroxy-6,16a-dimethyl-20-oxo-2 -phenyl-4,6-pregnadieno-[3,2-c] pyrazole 21-aCetate, as described in U.S. Patent 3,300,483. 

Atrazine is successively transformed to 2,4,6-trihydroxy-l,3,5-triazine (Pelizzetti et al. 1990) by dealkylation of the alkylamine side chains and hydrolytic displacement of the ring chlorine and amino groups (Figure 1.3). A comparison has been made between direct photolysis and nitrate-mediated hydroxyl radical reactions (Torrents et al. 1997) the rates of the latter were much greater under the conditions of this experiment, and the major difference in the products was the absence of ring hydroxylation with loss of chloride. 

In plant tissues, various enzymes convert the hydroperoxides produced by LOX to other products, some of which are important as flavor compounds. These enzymes include hydroperoxide lyase, which catalyzes the formation of aldehydes and oxo acids hydroperoxide-dependent peroxygenase and epoxygenase, which catalyze the formation of epoxy and hydroxy fatty acids, and hydroperoxide isomerase, which catalyzes the formation of epoxyhydroxy fatty acids and trihydroxy fatty acids. LOX produces flavor volatiles similar to those produced during autoxidation, although the relative proportions of the products may vary widely, depending on the specificity of the enzyme and the reaction conditions. 

As can be expected, the high-temperature processing runs the risk of enhancing side and consecutive reactions. Decarboxylation of the main product was found and increases with temperature (see Fig. 7). This is illustrated at the example of the synthesis of 2,4,6-trihydroxy benzoic acid from phloroglucinol, as this molecule is even more sensitive to thermal destruction due to the enhanced electron richness of the aromatic core by presence of a third hydroxyl group (Hessel et al. 2007). 

Spectinomycin Spectinomycin, 4a,7,9-trihydroxy-2-methyl-6,8-fcw-(methylamino)-per-hydroxypyrano-[2,3-b]benzodioxan-4-one (32.7.1), which is isolated from products of the actinomycete Streptomyces spectabilis, is an aminocyclitol, yet it is not an aminoglycoside antibiotic since it does not contain either an amino sugar region or a glycoside bond [316-324]. 

Natamycin Natamycin, a mixture of stereoisomeric 22-[(3-amino-3,6-dideoxy-p-D-mannopyranosyl)oxy]-1,3,26-trihydroxy-12-methyl- lO-oxo-6,11,28-trioxatricy-clo[22.3.1.0. ]-octacosa-8,14,16,18,20,penten-25-carboxylic acid (35.1.3), like amphotericin and nystatin, is a polyene antibiotic that is isolated from the products of the vital activity of the actinomycete Streptomyces natalensis [15-17]. 

Phenolic compounds have also been oxidatively polymerized to humic substances by clay minerals (29) and by the mineral fraction of a latasol (66). After a 10-day equilibration period, montmoril-lonite and illite clay minerals yielded 44 to 47% of the total added phenolic acids as humic substances whereas quartz gave only 9%. Samples of a latasol yielded over 63% of the total amount, from mixtures in varied proportion, of mono-, di- and trihydroxy phenolic compounds as humic substances (66). Extractions of the reaction products yielded humic, fulvic, and humin fractions that resembled soil natural fractions in color, in acid-base solubility, and in infrared absorption spectra. Wang and co-workers (67) further showed that the catalytic polymerization of catechol to humic substances was, enhanced by the presence of A1 oxide and increased with pH in the 5.0 to 7.0 range. Thus the normally very reactive products of Itgnin degradation can be linked into very stable humic acid polymers which will maintain a pool of potentially reactive phytotoxins in the soil. 

The major products formed from hexoses that react in aqueous acidic solution are 5-(hydroxymethyl)-2-furaldehyde, levulinic acid, and polymeric materials. In addition, many minor dehydration products are found. In a study41 of D-fructose, 2-(2-hydroxyacetyl)furan (13), 2-acetyl-3-hydroxyfuran (isomaltol 16), 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one, and 3,4,5-trihydroxy-3,5-hexadien-2-one (acetylformoin) were identified. Products not formed solely by dehydration mechanisms include acetone,56 formaldehyde, acetalde-... 

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