Indole Building Blocks

Catalytic Enantioselective Diels-Alder Reactions of Benzoquinones and Vinylindoles with Chiral Magnesium Phosphate Complexes was written by Bai, Yujia;Yuan, Jinping;Hu, Xiaoyue;Antilla, Jon C.. And the article was included in Organic Letters in 2019.SDS of cas: 827-01-0 This article mentions the following:

Tetrahydrocarbazole and its derivatives have received much attention due to the prevalence of this scaffold in natural products and their use in organic synthesis. The authors have developed a Diels-Alder reaction of benzoquinones and 3-vinylindoles catalyzed by chiral magnesium phosphate complexes to provide tetrahydrocarbazole derivatives in excellent yields and enantioselectivities (up to >99% yield, 99% ee). This transformation features a wide substrate scope, excellent enantioselectivities, and mild conditions. In the experiment, the researchers used many compounds, for example, 5-Chloroindole-3-carboxaldehyde (cas: 827-01-0SDS of cas: 827-01-0).

5-Chloroindole-3-carboxaldehyde (cas: 827-01-0) belongs to indole derivatives. In addition to tryptophan, indigo, and indoleacetic acid, numerous compounds obtainable from plant or animal sources contain the indole molecular structure. They are capable of binding to a variety of receptors with high affinity and thus have applications in a wide range of therapeutic areas.SDS of cas: 827-01-0

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Synthesis of 4-bromo- and 6-bromoindoles and of 4-amino- and 6-aminoindoles and reactions of these compounds was written by Plieninger, Hans;Suehiro, T.;Suhr, K.;Decker, M.. And the article was included in Chemische Berichte in 1955.Synthetic Route of C9H6BrNO2 This article mentions the following:

Bromination of o-O₂NC₆H₄Me gives a mixture of 4,2- and 6,2-Br(O₂N)C₆H₃Me which with (CO₂Et)₂ in the presence of NaOEt yields a mixture of the Na salts of 4,2- (I) and 6,2-Br(O₂N)C₆H₃COCO₂H (II); on cooling the aqueous solution, the less soluble salt of I separates first, and with HCl gives I, m. 138-40°; the acidified mother liquor yields II, m. 117°. I and II can be reduced with Fe(OH)₂ to 4-bromo-2-carboxyindole (III), m. 263°, and the 6-Br isomer (IV), m. 220-4°, resp. Refluxed with Cu₂Br₂ and quinoline, these acids are decarboxylated to 4- and 6-bromoindoles, yellow oil and solid m. 94°, resp.; refluxing with Cu₂Cl₂ gives 4-and 6-chloroindoles, colorless oil, and solid m. 78-80°, resp. Refluxing III with a 15% solution of HCl in EtOH gives the Et ester, m. 161°; Et ester of IV, m. 186-7°. The Et ester of III with piperidine and 30% aqueous formalin in the presence of 60% aqueous AcOH produces 3-piperidinomethyl-4-bromo-2-carbethoxyindole (V), m. 148°; similarly, the Et ester of IV yields the 6-Br isomer (VI), m. 122-4°. 4-Bromoindole (VII), with pyridine, 30% aqueous formalin, and 60% aqueous AcOH yields 3-piperidinomethyl-4-bromoindole (VIII), m. 190°, on cooling, and methylation with Me₂SO₄ in EtOH and treatment with 1-carbethoxy-2-cyclohexanone and Na-OEt produces 1-(4-bromo-α-skatyl)-1-carbethoxy-2-cyclohexanone (IX), m. 160-5°. V similarly gives 1-(2-carbethoxy-4-bromo-α-skatyl)-1-carbethoxy-2-cyclohexanone (X), m. 201°, and VI gives the 6-bromo-α-skatyl isomer, m. 194-6°. VIII with BzOH, Me₂SO₄, and 1-carbobenzyloxy-2-cyclohexanone in the presence of BzOK gives 1-(4-bromo-α-skatyl)-1-carbobenzyloxy-2-cyclohexanone (XI), m. 116-17°. Attempts to cyclize IX in the presence of Mg in THF, Na in xylene, or Na in liquid NH₃, and to cyclize X in the presence of Na or Li under various conditions all failed. 1-Benzyl-4-bromoindole with MeMgI and solid CO₂ yields a complex which can be destroyed to give 1-benzyl-4-carboxyindole, m. 178-80°. III with concentrated NH₄OH gives 4-aminoindole, m. 108°; similarly IV yields 6-aminoindole, m. 68-70°, forming with Ac₂O and pyridine the N-Ac derivative, m. 169°. In the experiment, the researchers used many compounds, for example, 4-Bromo-1H-indole-2-carboxylic acid (cas: 16732-64-2Synthetic Route of C9H6BrNO2).

4-Bromo-1H-indole-2-carboxylic acid (cas: 16732-64-2) belongs to indole derivatives. Indole produced by Proteus, Pseudomonas, Escherichia and other species was shown to be a growth promoting factor in Arabidopsis thaliana. It is used in perfumery and in making tryptophan, an essential amino acid, and indoleacetic acid (heteroauxin), a hormone that promotes the development of roots in plant cuttings.Synthetic Route of C9H6BrNO2

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Synthesis and antimicrobial activity of tetrodecamycin partial structures was written by Paintner, Franz F.;Allmendinger, Lars;Bauschke, Gerd;Berns, Caroline;Heisig, Peter. And the article was included in Bioorganic & Medicinal Chemistry in 2003.SDS of cas: 14204-27-4 This article mentions the following:

An efficient synthetic approach to the core structure I (R = H) of the novel polyketide antibiotic tetrodecamycin was developed. This approach features the acid-catalyzed cyclization of a tert-butyldimethylsilyl protected Me α-(γ-hydroxyacyl) tetronate, leading to the novel tricyclic ring skeleton exhibited by I (R = H), and an efficient strategy for the parallel introduction of the cis-diol and exo-methylene function. In addition to I (R = H), a diastereomer of I (R = H), analog II, and several other derivatives were prepared and evaluated for their antibacterial activities against Staphylococcus aureus (including MRSA) and Enterococcus faecalis and for their cytotoxic activities against human leukemia cell lines (HL-60, Jurkat T-cells). While I (R = H) did not inhibit the growth of the Gram-pos. pathogens (MICs >128 μg mL^-1), analog II and 2-naphthoyl derivative I (R = 2-naphthoyl) showed promising antibacterial activities with MICs of 4-16 μg mL^-1. Remarkably, the antibacterial activity of these compounds was paralleled by cytotoxicity (IC₅₀ 10-23 μM). The reactive exo-methylene moiety was shown to be crucial, but not sufficient on its own, for both the antibacterial and the cytotoxic activities. In the experiment, the researchers used many compounds, for example, 2-(Phenylthio)isoindoline-1,3-dione (cas: 14204-27-4SDS of cas: 14204-27-4).

2-(Phenylthio)isoindoline-1,3-dione (cas: 14204-27-4) belongs to indole derivatives. Indole, also called Benzopyrrole, a heterocyclic organic compound occurring in some flower oils, such as jasmine and orange blossom, in coal tar, and in fecal matter. Indole plays a fundamental role for QS in E. coli, being one of the signal molecules responsible for the transcription of a variety of genes (gabT, and tnaB ASTD). SDS of cas: 14204-27-4

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Selectivity, Speciation, and Substrate Control in the Gold-Catalyzed Coupling of Indoles and Alkynes was written by Epton, Ryan G.;Unsworth, William P.;Lynam, Jason M.. And the article was included in Organometallics in 2022.Safety of 6-Nitro-1H-indole This article mentions the following:

A convenient and mild protocol for the Au-catalyzed intermol. coupling of substituted indoles with carbonyl-functionalized alkynes to give vinyl indoles is reported. This reaction affords 3-substituted indoles in high yield, and in contrast to the analogous reactions with simple alkynes which give bisindolemethanes, only a single indole is added to the alkyne. The protocol is robust and tolerates substitution at a range of positions of the indole and the use of ester-, amide- and ketone-substituted alkynes. The use of 3-substituted indoles as substrates results in the introduction of the vinyl substituent at the 2-position of the ring. A combined exptl. and computational mechanistic study revealed that the Au catalyst has a greater affinity to the indole than the alkyne, despite the C-C bond formation step proceeding through an η²(π)-alkyne complex, which helps to explain the Stark differences between the intra- and intermol. variants of the reaction. Also the addition of a 2nd indole to the carbonyl-containing vinyl indole products is both kinetically and thermodynamically less favored than in the case of more simple alkynes, providing an explanation for the observed selectivity. Finally, a highly unusual Au-promoted alkyne dimerization reaction to form a substituted Au pyrylium salt was identified and studied. In the experiment, the researchers used many compounds, for example, 6-Nitro-1H-indole (cas: 4769-96-4Safety of 6-Nitro-1H-indole).

6-Nitro-1H-indole (cas: 4769-96-4) belongs to indole derivatives. Indole produced by Proteus, Pseudomonas, Escherichia and other species was shown to be a growth promoting factor in Arabidopsis thaliana.Indole was synthesized in moderate yield via an o-naphthoquinone catalyzed tandem cross-coupling of substituted aniline and benzylamine under aerobic oxidation conditions.Safety of 6-Nitro-1H-indole

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Development of Proneurogenic, Neuroprotective Small Molecules was written by MacMillan, Karen S.;Naidoo, Jacinth;Liang, Jue;Melito, Lisa;Williams, Noelle S.;Morlock, Lorraine;Huntington, Paula J.;Estill, Sandi Jo;Longgood, Jamie;Becker, Ginger L.;McKnight, Steven L.;Pieper, Andrew A.;De Brabander, Jef K.;Ready, Joseph M.. And the article was included in Journal of the American Chemical Society in 2011.Category: indole-building-block This article mentions the following:

Degeneration of the hippocampus is associated with Alzheimer’s disease and occurs very early in the progression of the disease. Current options for treating the cognitive symptoms associated with Alzheimer’s are inadequate, giving urgency to the search for novel therapeutic strategies. Pharmacol. agents that safely enhance hippocampal neurogenesis may provide new therapeutic approaches. We discovered the first synthetic mol., named P7C3, which protects newborn neurons from apopotic cell death, and thus promotes neurogenesis in mice and rats in the subgranular zone of the hippocampal dentate gyrus, the site of normal neurogenesis in adult mammals. We describe the results of a medicinal chem. campaign to optimize the potency, toxicity profile, and stability of P7C3. Systematic variation of nearly every position of the lead compound revealed elements conducive toward increases in activity and regions subject to modification. We have discovered compounds that are orally available, nontoxic, stable in mice, rats, and cell culture, and capable of penetrating the blood-brain barrier. The most potent compounds are active at nanomolar concentrations Finally, we have identified derivatives that may facilitate mode-of-action studies through affinity chromatog. or photo-crosslinking. In the experiment, the researchers used many compounds, for example, 5-Bromo-2,3-dimethyl-1H-indole (cas: 4583-55-5Category: indole-building-block).

5-Bromo-2,3-dimethyl-1H-indole (cas: 4583-55-5) belongs to indole derivatives. In addition to tryptophan, indigo, and indoleacetic acid, numerous compounds obtainable from plant or animal sources contain the indole molecular structure. Due to this activity, the indole ring system has become an important component or intermediate in the synthesis of heterocycles.Category: indole-building-block

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Diastereo- and Enantioselective Synthesis of Borylated 3-Hydroxyoxindoles by Addition of gem-Diborylalkanes to Isatins was written by Zhou, Yuan;Xiong, Tong;Zhou, Li-Yan;Li, Hong-Yan;Xiao, You-Cai;Chen, Fen-Er. And the article was included in Organic Letters in 2022.Recommanded Product: 5-Isopropylindoline-2,3-dione This article mentions the following:

The catalytic asym. synthesis of borylated 3-hydroxyoxindoles by addition of gem-diborylalkanes to isatins is disclosed. Chiral 3-hydroxyoxindoles bearing two contiguous stereogenic centers were produced in up to >20:1 dr and 99% ee. The synthetic utility of the corresponding products is presented through several transformations of the boryl moiety. This report provides an efficient strategy to incorporate a boryl functional group toward the synthesis of 3-hydroxyoxindoles. In the experiment, the researchers used many compounds, for example, 5-Isopropylindoline-2,3-dione (cas: 150560-58-0Recommanded Product: 5-Isopropylindoline-2,3-dione).

5-Isopropylindoline-2,3-dione (cas: 150560-58-0) belongs to indole derivatives. In addition to tryptophan, indigo, and indoleacetic acid, numerous compounds obtainable from plant or animal sources contain the indole molecular structure. It is used in perfumery and in making tryptophan, an essential amino acid, and indoleacetic acid (heteroauxin), a hormone that promotes the development of roots in plant cuttings.Recommanded Product: 5-Isopropylindoline-2,3-dione

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles