Indole-3-acrylic acid

Fildes, P. Inhibition of bacterial growth by indole acrylic acid and its... 

Indol acrylic acid Poly(methyl methacrylate)... 

The Diels-Alder reactions of the methyl or ethyl ester of benzenesulfonylindole-2-acrylic acid with several l-alkoxycarbonyl-l,2-dihydropyridines are reported and only a single stereoisomer was obtained, as in the case of l-methoxy(ethoxy)-carbonyl-1,2-dihydropyridines. However, when the Diels-Alder reaction of 17 was carried out with 8g[R = (CHsjsC], a mixture of two stereoisomers 18gand25were obtained in a 1 1 ratio (65% total yield). The bulky rerr-butyl group creates sufficient steric interference with the indole ring to cause the loss of stereochemistry ... 

Norharman is uncompetitive with L-tryptophan for rabbit intestinal IDO and linearly competitive with L-tryptophan for mouse liver TPO. Some p-carbolines in 11-13 selectively inhibit one enzyme or the other. Specific inhibition effect of p-carbolines is different between TPOs from mammalian and Pseudomonad sources. Similarly, indole-3-acetamide, -acetonitrile, and -acrylic acid exhibit a potent inhibition for mammalian TPO, while they moderately inhibit the Pseudomonad enzyme. These indole derivatives show no inhibition for IDO. From these results, the difference of the structures of the active sites among these enzymes from various sources is suggested. 

Zembower and co-workers explored the double Heek reaetion in one-pot and completed the synthesis of DG-041 1, EPj receptor antagonist [18]. A practically reliable catalytic system Pd(OAc)2/(o-tolyl)3 afifeeted both the transformations, intramolecular Heck reaction of bromo intermediate 38 to form indole ring, as well as intermolecular Heck coupling of resulting indole intermediate with acrylic acid 39 to give 40, en route to 41 (Seheme 9.10). 

For MALDI experiments, one needs to dissolve the polymer in very dilute (1 x 10 m solution of polymer with the matrix (1 to 2 x 10 M) generally using the same solvent e.g. methanol, acetone, THF). Typical matrices are Indole, or acrylic acid. One mixes the matrix/polymer solution (varies a lot) and places it on probe (0.5-2 xl) to dry. The MALDI experiment can then be undertaken. 

Esters of indole-3-carboxylic acid can be made in two steps starting with an o-bromoaniline and an acrylate cstcr[2]. 

Indoles can also be alkylated by conjugate addition under alkaline conditions. Under acidic conditions, alkylation normally occurs at C3 (see Section 11.1). Table 9.1 includes examples of alkylation by ethyl acrylate, acrylonitrile, acrylamide and 4-vinylpyridine. 

An interesting addition of ethyl acrylate has been reported in the case of l-methyl-2-ethylidenepyrrolidine. An unsaturated amino ketone 144 is formed, which rearranges to 1,7-dimethyloctahydroindole (145) on reduction with formic acid, as established by dehydrogenation to 1,7-dimethyl-indole (Scheme 12) 217). 

Figure 11.11 Pyrogram of a paint sample collected from a decorative frame of the Universal Judgement by Bonamico Buffalmacco (fourteenth century, Monumental Cemetery of Pisa, Italy). Pyrolysis was performed with a microfurnace pyrolyser, at 600°C, in the presence of HMDS. 1, Benzene 2, ethyl acrylate 3, methyl methacrylate 4, acetic acid, trimethyl silyl ester 5, pyrrole 6, toluene 7, 2 methylpyrrole 8, 3 methylpyrrole 9, crotonic acid 10, ben zaldehyde 11, phenol 12, 2 methylphenol 13, 4 methylphenol 14, 2,4 dimethyl phenol 15, benzyl nitrile 16, 3 phenylpropionitrile 17, indole 18, phthalate 19, phthalate 20, ben zyl benzoate HMDS pyrolysis products [27]...

A few additional Pd-catalyzed schemes have been employed for Ilac type cyclization chemistry. Palladium-phenanthroline complexes were used by the Ragaini group to prepare indoles via the intermolecular cyclization of nitroarenes and alkynes in the presence of carbon monoxide <06JOC3748>. Jia and Zhu employed Pd-catalysis for the annulation of o-haloanilines with aldehydes <06JOC7826>. A one-pot Ugi/Heck reaction was employed in the preparation of polysubstituted indoles from a four-component reaction system of acrylic aldehydes, bromoanilines, acids, and isocyanides <06TL4683>. 

The vinyl triflate of Komfeld s ketone has been subjected to Heck reactions with methyl acrylate, methyl methacrylate, and methyl 3-(Af-rerf-butoxycarbonyl-lV-methyl)amino-2-methylenepropionate leading to a formal synthesis of lysergic acid [259]. A similar Heck reaction between l-(phenylsulfonyl)indol-5-yl triflate and dehydroalanine methyl ester was described by this research group [260]. Chloropyrazines undergo Heck couplings with both indole and 1-tosylindole, and these reactions are discussed in the pyrazine Chapter [261], Rajeswaran and Srinivasan described an interesting arylation of bromomethyl indole 229 with arenes [262]. Subsequent desulfurization and hydrolysis furnishes 2-arylmethylindoles 230. Bis-indole 231 was also prepared in this study. 

Miki and Hachiken reported a total synthesis of murrayaquinone A (107) using 4-benzyl-l-ferf-butyldimethylsiloxy-4fT-furo[3,4-f>]indole (854) as an indolo-2,3-quinodimethane equivalent for the Diels-Alder reaction with methyl acrylate (624). 4-Benzyl-3,4-dihydro-lfT-furo[3,4-f>]indol-l-one (853), the precursor for the 4H-furo[3,4-f>]indole (854), was prepared in five steps and 30% overall yield starting from dimethyl indole-2,3-dicarboxylate (851). Alkaline hydrolysis of 851 followed by N-benzylation of the dicarboxylic acid with benzyl bromide and sodium hydride in DMF, and treatment of the corresponding l-benzylindole-2,3-dicarboxylic acid with trifluoroacetic anhydride (TFAA) gave the anhydride 852. Reduction of 852 with sodium borohydride, followed by lactonization of the intermediate 2-hydroxy-methylindole-3-carboxylic acid with l-methyl-2-chloropyridinium iodide, led to the lactone 853. The lactone 853 was transformed to 4-benzyl-l-ferf-butyldimethylsiloxy-4H-furo[3,4- 7]indole 854 by a base-induced silylation. Without isolation, the... 

Indole reacts with dimethylacetylene dicarboxylate giving tetramethylcar-bazol-l,2,3,4-tetracarboxylate as a major product,formed via 384 (R = H, and/or geometric isomer) and then Diels-Alder addition and dehydrogenation. /V-Acetylindole undergoes an extraordinary double condensation and cyclization with methyl acrylate in the presence of palladium(II) acetate in acetic acid giving 9% of the dimethyl 9-acetylcarbazole-2,3-dicar-boxylate 393 as well as 394 and 395, the products of monosubstitution at the indole a and S-positions. ... 

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