Oxindole-3-acetic acid

R = H oxindole-3-acetic acid R OH dioxindole-3-acetic acid... 

Oxidation without decarboxylation. Epstein et al. [4] observed that lAA was destroyed in the endosperm of germinating com kernels at a greater rate than [ ClCOj was evolved from carboxyl labeled lAA, indicating that there must be turnover without decarboxylation. Nonhebel et al. [155] also reported that the rate of decarboxylation was lower than expected when [ C]-IAA was fed to maize seedlings. In maize, the product of non-decarboxylative oxidation of lAA in vivo is oxindole-3-acetic acid (OxIAA Fig. 4)... 

DiOxIAA dioxindole-3-acetic acid (3-hydroxy-2-indolone-3-acetic acid 7-OH-OxIAA-glc, 7-hydroxy-oxindole-3-acetic acid-7 -0-B-D-glucopyranoside... 

OH-OxIAA-glc 7-hydroxy oxindole-3-acetic acid-7 -0-yff-D-glucopyranoside... 

The reduction of o-nitrophenyl acetic acids or esters leads to cyclization to oxindoles. Several routes to o-nitrophenylacetic acid derivatives arc available, including nitroarylation of carbanions with o-nitroaryl halides[2l,22] or trif-late[23] and acylation of o-nitrotoluenes with diethyl oxalate followed by oxidation of the resulting 3-(u-nitrophenyl)pyruvate[24 26]. 

Oxadiazonphenol, see Oxadiazon Oxalic acid, see Acetic acid, 2-Chlorophenol, Cyclohexene, 2,4-D, 2,4-Dinitrophenol, 1,4-Dioxane, Glycine. 2-Methylphenol, Naphthalene, 4-Nitroaniline, 4-Nitrophenol, Parathion, Phenol, Picloram. 2,4,5-T Oxamic acid, see Acetamide 1 -Oxa-2-oxocycloheptane, see Cyclohexane Oxindole, see Indole... 

Studies with corynantheine-type oxindole alkaloids have also been conducted [48]. Since rhynchophylline (68) and isorhynchophylline (69), Fig. (17), have an H-15 and H-20 trans relationship, epimerization would be expected to occur only at C-7. And indeed, this proved to be the case acetic acid treatment yielded a ratio of 70 30 (68 69). Even though... 

Traditional methods for bromination of indoles are not very satisfactory. For example, use of NBS in aqueous acetic acid generally gives rise to oxindoles or indolenines rather than to bromoindoles. Bromination is better in aprotic solvents but yields are still often poor and/or conditions vigorous. By contrast, NBS-silica brominated skatole rapidly at room temperature in... 

Folkes, L. K., Rossiter, S., and Wardman, P., 2002, Reactivity toward thiols and cytotoxicity of 3-methylene-2-oxindoles, cytotoxins from indole-3-acetic acids, on activation by peroxidases, Chem. Res. Toxicol. 15 877-882. 

In general, the chemical properties of nareline are those expected of a compound containing the complex functionality of (173), including the unusual hemiacetal unit formed from an aldehyde and a hydroxylamine derivative. However, the oxidation by chromic acid in acetic acid takes a course that would have been difficult to predict, and affords a product, oxonareline (175), which is presumably formed from (173) by oxidative fission of the 2, 3, Nb system to give an oxindole function (176), followed by internal acetal formation between oxygen attached to C-5 and a carbinolamine equivalent at C-3.98... 

Evidence that aminonitriles and 2-aminoindoles are the intermediates in this cycli-zation leading to indoles was obtained with a-substituted 2-nitrophenylacetonitriles. The final absorption of 1 mol of hydrogen was slow in the hydrogenation of 42, ammonia was not formed, and the aminonitrile 43 was the product, which cyclized to the oxindole 44 in the presence of acid. The hydrogenation of P-dimethylaminoethyl-sub-stituted nitronitrile 45 over 10% Pd-C in ethyl acetate at 80°C afforded ammonia and the indole 46. However, the hydrogenation of 45 over 8% Pd-C in acetic acid at 80°C did not result in the formation of an appreciable amount of ammonia, and a crystalline dihydrochloride corresponding to an amidine structure 47 could be prepared from the product (Scheme 9.17). 

When 7-aeyl-7 -reserpine derivatives (XV) are refluxed in dilute methanol with a few drops of acetic acid, conversion into the corresponding oxindole (XIX) with concomitant formation of the five-membered spiro-ring C takes place. Under these conditions, also, carbon... 

Oxindole.—When ortho-nitro phenyl acetic acid is reduced to the ortho-amino phenyl acetic acid, the latter, being a gawwa-amino acid, loses water yielding a lactam which is known as oxindole. 

Di-oxindole.— Similarly a di-hydroxy compound known as di-oxin-dole is obtained as a lactam anhydride from ortho-amino mandellic acid, ortho-amino phenyl hydroxy acetic acid. 

Indoxyl.—One more derivative of indole must be mentioned connected with the synthetic production of indigo. Isomeric with oxindole is another mono-hydroxy indole known as indoxyl. It is prepared from phenyl glycine or//fo-carboxylic acid, anthranil acetic acid. 

Recently, 2-(2-nitrophenylsulfenyI)-3-methyl-3-bromoindolenine (BNPS-skatole) has replaced N-bromosuccinimide, which had been used frequently in earlier studies. At low reagent to protein tryptophan ratios, in 50% aqueous acetic acid, BNPS-skatole reacts selectively with tryptophan residues converting these to the oxindole derivative. Methionine is concommitantly converted to the sulfoxide. At high concentrations of reagent, slow selective cleavage (to the extent of 15-60%) of the peptide bonds involving tryptophanyl residues is... 

Monoterpene Bases.—Yohimbine-Corynantheine (and Related Oxindoles)-Pier aline Group. It is well known that 3,4-dehydroyohimbane (35a) is reduced by zinc-acetic acid to a mixture of yohimbane (35c) and i/ -yohimbane (35d) however, when 10-methoxy-3,4-dehydroyohimbane (35b) was similarly treated, a 2,3,4,7-tetrahydro-derivative (17 % yield) was formed as well as the corresponding 10-methoxy-yohimbanes. It was shown that this did not arise by further reduction of either of the methoxy-yohimbanes and no explanation is yet available for this interesting difference. Reserpine, a 6-methoxyindole, underwent C(3)-N(4) bond fission on reaction with zinc-acetic acid, as did indoles with no ring A methoxy-group. Cleavage of the C(3)-N(4) bond with the formation of N(4)-cyano-C(3)-alkoxy- or hydroxy-seco-derivatives was observed when yohimbine, i/ -yohimbine, and methyl reserpate were subjected to von Braun degradation conditions in alcohol or aqueous solution. 

---