3-Indolylacetic acid

The o-nitrobenzenesulfenamide has been used for the protection of amino acids. o-Nitrobenzenesulfenamides, B, are also cleaved by acidic hydrolysis (HCl/Et20 or EtOH, 0°, 1 h, 95% yield)" by nucleophiles (13 reagents, 5 min-12 h, 90% cleaved) by PhSH or HSCH2CO2H, 22°, 1 h by 2-mercaptopyri-dine/CH2Cl2, 1 min, 100% yield) by NH4SCN, 2-methyl-1-indolylacetic acid and by catalytic desulfurization (Raney Ni/DMF, column, a few hours, satisfactory yield). 

A) 2-Methyl-5-Methoxy-3-lndolylacetic Anhydride Dicyclohexylcarbodiimide (10 g, 0.049 mol) is dissolved in a solution of 2-methyl-5-methoxy-3-indolylacetic acid (22 g, 0.10 mol) in 200 ml of THF, and the solution Is allowed to stand at room temperature for 2 hours. The precipitated urea is removed by filtration, and the filtrate is evaporated in vacuo to a residue and flushed with Skellysolve B. The residual oily anhydride is used without purification in the next step. 

By careful choice of both the reaction conditions and the phenolic compound used, it may be possible to produce a colour that is characteristic of a particular carbohydrate or related group, so giving some degree of specificity to the method. Thus, Seliwanoff s test uses hydrochloric acid and either resorcinol or 3-indolylacetic acid to measure fructose with minimal interference from glucose. The colour produced by pentoses with orcinol (Bial s reagent) or p-bromoaniline is sufficiently different from that produced by hexoses to permit their quantitation in the presence of hexoses. However, none of the methods based on the formation of furfural or its derivatives can be considered to be entirely specific. 

Pindur et al. reported the synthesis of carazostatin (247) starting from the 2-vinylindole 958, which previously served as the key building block in the total synthesis of carbazoquinocin C (274) (see Scheme 5.130). The 2-vinylindole (958), readily available in four steps starting from Af-(phenylsulfonyl)indole (956), was transformed to the indolylacetic acid (1568) by treatment with KCN and paraformaldehyde followed by alkaline hydrolysis. Subsequent acid-catalyzed polar cyclization of 1568 led to carazostatin (247) (648) (Scheme 6.1). 

NT390 Chirek, Z. Physiological and biochemical effects of morphactin IT3233 NT401 on callus and tumor tissues of Nicoti-ana tabacum cultured in vitro. IV. Beta-indolylacetic acid oxidase activity. 

Indolylacetic acid derivatives were prepared by the ring closure of the appropriate N-(y-crotyl)-o-haloaniline derivative (3.11.).14 Although the reported yields of the original transformations15 were only mediocre, serious efforts were made to improve the method, due mainly to the value of the formed products in medicinal chemistry. 

The combination of the formation of palladium(II) complexes in the oxidative addition of unsaturated halides onto palladium(O), and the palladium(II) mediated ring closure of olefins allows for the elimination of the oxidant. The ring closure of the methallyl-aniline derivative shown in 3.67. in the presence of /J-bromostyrcnc and a catalytic amount of palladium led to the ring closed - coupled product.84 The ring closure might also be accompanied by other follow-up reactions. 2-Methallyl-anilines were converted for example to indolylacetic acid derivatives in the presence of carbon monoxide.85... 

In order to study how a silatrane group which is present in phytohormones influences their activity we have investigated the action of silatranylmethyl esters of 2-methyl-phenoxyacetic, 4-chlorophenoxyacetic and 3-indolylacetic acids on the suspended cul-... 

Table 28. The influence of 3-indolylacetic acid (I) and its silatranylmethyl ester (II) on the growth of cultures of plant tissues and wheat coleoptiles...

Heteroauxin silatranylmethyl ester stimulates the growth of the cultures of tobacco and soya tissues more effectively than 3-indolylacetic acid and itsethylester. At the same time, on wheat coleoptiles heteroauxin silatranylester and 3-indolylacetic ester display almost similar effects. 

In plants 3-indolylacetic acid is inactivated by 3-indolylacetic oxidase. A comparative study of the resistance of 3-indolylacetic acid and heteroauxin silatranylmethyl ester to crystalline peroxidase of horseradish (20 mkg/ml) has shown that the first compound decomposes within 10 minutes whereas the second compound does not decompose during the experiment (90 min) (Fig. 18). 

Conversion into 3-indolylacetic acid. In a 1-litre flask, fitted with a reflux condenser, place a solution of 35.2 g (0.72 mol) of sodium cyanide (CAUTION) in 70 ml of water, then add 25 g (0.144 mol) of gramine and 280 ml of 95 per cent ethanol. Boil the mixture under reflux for 80 hours. Dilute the cooled reaction mixture with 350 ml of water, shake with a little activated charcoal (e.g., Norit), filter and concentrate to about 350 ml under reduced pressure (water pump) in order to remove most of the alcohol. Cool to about 5 °C, filter off- the solid and wash it with a little cold water keep the filtrate (A). Recrystallise the solid from ethanol-ether to obtain 5.0 g (20%) of 3-indolylacetamide, m.p. 150-151 °C. 

Concentrate the filtrate (A) to about 300 ml, cool to 5-10 °C and add concentrated hydrochloric acid dropwise and with vigorous stirring (fume cupboard hydrogen cyanide is evolved) to a pH of 1-2 (about 50 ml) a crude, slightly pink 3-indolylacetic acid is precipitated. The yield of crude acid, m.p. 159-161 °C, is 20 g. Recrystallise from 1,2-dichloroethane containing a small amount of ethanol 17.5 g (70%) of pure 3-indolylacetic acid, m.p. 167-168 °C, are obtained. 

Taurine conjugation with bile acids, phenylacetic acid, and indolylacetic acid seems to be a minor process in most species, but in the pigeon and ferret, it occurs extensively. Other infrequently reported conjugations include serine conjugation of xanthurenic acid in rats excretion of quinaldic acid as quinaldylglycyltaurine and quinaldylglycylglycine in the urine of the cat, but not of the rat or rabbit and conversion of furfural to furylacrylie acid in the dog and rabbit, but not in the rat, hen, or human. The dog and... 

D) 1 -p-Chlorobenzoyl-2-Methyl-5-Methoxy-3-Indolylacetic Acid A mixture of 1 g ester and 0.1 g powdered porous plate is heated in an oil bath at 210°C with magnetic stirring under a blanket of nitrogen for about 2 hours. No intensification of color (pale yellow) occurs during this period. After cooling under nitrogen, the product is dissolved in benzene and ether, filtered, and extracted with bicarbonate. The aqueous solution is filtered with suction to remove ether, neutralized with acetic acid, and then acidified weakly with dilute hydrochloric acid. The crude product (0.4 g, 47%) is recrystallized from aqueous ethanol and dried in vacuo at 65°C MP 151°C. 

Preparation of l-(p-nitrobenzoyl)-5-methoxy-2-methyl-3-indolylacetic acid ... 

Systemic auxin, acting like indolylacetic acid... 

SYNS HETEROAUXIN IA. p-INDOLEACETIC ACID p-INDOLE-3-ACETIC ACID 3-INDOLE-ACETIC ACID INDOLYLACETIC ACID a-INDOL-3-YL-ACETIC ACID P-INDOLYLACETIC ACID ... 

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