Indole carboxylates

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

This trend is also observed in the reactions with nitrogen- and carbon-centered nucleophiles (2001H425). Thus, the reaction of 109 with sodium indolyl in DMF affords methyl 2-(indol-l-yl)indole-3-carboxylate (188, 77%). In better yield, 2-(indol-l-yl)indole-3-carbaldehyde (189, 95%) is formed in the corresponding reaction (99H1157) of 115a (Scheme 28). Sodium imidazolyl reacts with 109 in DMF at 60°C to afford methyl 2-(imidazol-l-yl)indole-3-carboxylate (190,28%), methyl indole-3-carboxylate (191,11 %), and unreacted 109 (36%). In contrast, under the same conditions, 110 and 115a provide higher yields of methyl 2-(imidazol-... 

Ethyl tram-5 a,9 a-dihydro-1 H- -benzazepine-1 -carboxy late (2), a photorearrangement product of ethyl 3,3a,7a,7b-tetrahydro-l//-cycIobut[6]indole-3-carboxylate (1), on treatment with tet-rachloro-l,2-benzoquinone in benzene undergoes oxidation to the l//-l-benzazepine 3.109... 

CN (2a,6a,8a,9aa)-l/7-Indole-3-carboxylic acid octahydro-3-oxo-2,6-methano-2/f-quinolizin-8-yl ester base... 

CN i//-Indole-3-carboxylic acid endo-8-methyl-8-azabicyclo[3.2.1]oct-3-yl ester... 

QH7N 120-72-9) see Indalpine Indoramin Tinazoline hydrochloride Trandolapril indole-3-carbonyl chloride (C H ClNO 59496-25-2) see Tropisetron indole-3-carboxylic acid... 

CijH NOj 771-50-6) see Dolasetron mesilate Tropisetron l/7-indole-3-carboxylic acid anhydride with trifluoroace-tic acid... 

C iH FjNO, J254S3-3I-0) see Dolasetron mesilate indole-3-carboxylic acid imidazolide (CiiHoNjO 99445-26-S) see Tropisetron (S)-indoline-2-carboxylic acid (QjH.jNOj 79815-20-6) see Perindopril ( )-2-(lH-indol-5-yl)-A -methylethenesulfonamide (CiiHijNjOjS 98623-49-5) see Naratriptan 5-(3-indolylmcthyl)hydantoin (Ci2H N,02 21753-16-2) see L-Tryptophan... 

Novel l//-imidazo[l,2-a]indole-3-carboxylates 47 were prepared <96SC745>. Thermolyses of halogenated 4,5-dicyanoimidazole derivatives 48 (X = H, Y = F, Cl X = 1, Y = Cl, Br, I) at 100-290 °C led to formation of perhaps the ultimate fused-ring imidazole, hexacaib(Hiitrilelris(iinidazo)triazene (HTT) <96JOC6666>. 

Condensation of aromatic methylesters such as methyl 4-methoxybenzoate 351 a or methyl 4-hydroxybenzoate 351b with excess sodium-HMDS 486 in a mixture of THF-l,3-dimethyl-imidazolin-2-one (DMEU) at 185 °C in a closed vessel affords 59 or 93% of 4-hydroxybenzonitrile 298 as well as 26% 352 with smooth cleavage of the aromatic methyl ether in 351a (Scheme 4.47). Methyl indole-3-carboxylate gives hkewise 3-cyanoindole in 81% yield [127] (cf. also ref [92] in section 4.3). 

Non-oxidafive novel aromatic acid decarboxylases, pyrrole-2-carboxylate decarboxylase and indole-3-carboxylate decarboxylase, were found in Bacillus... 

The carboxylafion of indole into indole-3-carboxylate was observed by the purified indole-3-carboxylate decarboxylase as well as by the whole cells. For the carboxylafion reaction, temperatures over 30°C were not appropriate. The activities at 10, 20, and 30°C were about the same. The activity was maximal at pH 8.0 (Tris-HCl buffer, 100 mM). As shown in Fig. 10, the resting cells of A. nicotianae F11612 also catalyzed the carboxylafion of indole efficiently in the reaction mixture containing 20 mM indole, 3M KHCO3, 100mM potassium phosphate buffer (pH 6.0) in a tightly closed reaction vessel. By 6h, 6.81 mM indole-3-carboxylic acid accumulated in the reaction mixture with a molar conversion yield of 34%. Compared to the carhoxylation of pyrrole by pyrrole-2-carboxylate decarboxylase, the lower value compared might derive from the lower solubility of indole in the reaction mixture. 

Resting cells of A. nicotianae FI1612 also catalyzed the carboxylafion of 2-methylindole and quinoxaline. The activities toward 2-methylindole and quinoxaline were 37 and < 1% of the activity toward indole, respectively. The reaction products of the reverse carboxylafion, indole-3-carboxylic acid and 2-methylindole-3-carboxylic acid, were isolated and identified through physicochemical analyses with the authentic compounds as reference. 

In the aligned primary structures of class I decarboxylases, the conserved amino acid residues are scattered over their primary structures. There have been few reports to identify the amino acid residues essential for catalytic activity or substrate binding. Huang et al. reported the E-X-P motif in the alignment analysis for 4-hydroxybenzoate decarboxylase of C. hydroxybenzoicum and its homologous unidentified proteins. The E-X-P motif is also conserved in pyrrole-2-carboxylate decarboxylase and indole-3-carboxylate decarboxylase (unpublished data). However, the corresponding motif sequence is not observed in the primary structures of 3,4-dihydroxybenzoate decarboxylase of E. cloacae P241. ... 

In Pseudomonas pyrrocinia, transformation was initiated by oxidation of the side chain to indole-3-acetate that was further degraded to indole-3-carboxylate before decarboxylation to indole (Figure 10.3c) (Liibbe et al. 1983). 

In total, 185 substances were found in the wing-sac liquid of male S. bilineata from a Costa Rican population. For a more detailed analysis the relative peak area of thirteen focus compounds was compared (Table 14.1). Of these nine were male-specific substances (indole, indol-3-carboxaldehyde, indole-3-carboxylic acid, 2-aminoacetophenon, anthranilic acid, SHJOH-dipyrrolofl -aT -dJpyrazine-5,10-dione (pyrocoll), indolo[2,l-b]quinazoline-6,12-dione (tryptanthrin), 2,6,10-trimethyl-3-oxo-6,10-dodecadienolide, and a compound C15H24O2 of unknown structure), three were fatty acids (tetradecanoic acid, hexadecanoic acid, and octadecanoic acid), and one a steroid (cholesterol). On average, the cumulative peak area of these substances made up 62.5 20.7% of the whole chromatogram area. 

The reduced electrophUicity of indole-3-carboxylic esters (they are vinylogous carbamates) means that they are much more versatile directors of lateral lithiation than the comparable benzoates, as illustrated by the synthesis of 564 (Scheme 221... 

The indole 22 was previously isolated from the sponge Dysidea etheria [110] and has now been obtained from the Antarctic ice bacterium ARK 13-2-437. The lipid phase of Hel45 delivered additionally N-(2-hydroxyethyl)-ll-octadecen-amide and the new natural products 17-methyl-16-octadecenoic acid [95] and indole-3-carboxylic acid thiomethyl ester (23). 

Contrary to carbon enterosorbents, Enterosgel does not possess an ability for selective removal of albumin-bound ligands regardless of their affinity with the protein carrier - weak (L-tryptophane), medium (sodium caprylate, deoxycholic acid), or strong (indole-3-carboxylic acid and unconjugated bilirubin). It means that if protein-bound toxins are removed by Enterosgel, this occurs simultaneously with adsorption of the carrier protein. 

Benzoic acid and naphthoic acid are formed by the oxidative carbonylation by use of Pd(OAc)2 in AcOH. /-Bu02H and allyl chloride are used as reoxidants. Addition of phenanthroline gives a favorable effect[360]. Furan and thiophene are also carbonylated selectively at the 2-position[361,3621. Indole-3-carboxylic acid is prepared by the carboxylation of 1-acetylindole using Pd(OAc)2 and peroxodisulfate (Na2S20s)[362a]. Benzoic acid derivatives are obtained by the reaction of benzene derivatives with sodium palladium mal-onate in refluxing AcOH[363],... 

In certain cases copper catalyzed processes might also be used for the N-alkynylation of azoles. Methyl indole-3-carboxylate was coupled with 1-bromo-2-triisopropylsilyl-acetylene in the presence of a copper-phenantroline catalyst to give the desired 1-ethynylindole derivative in excellent yield (6.74.),105... 

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