100-200 | - Page 17 of 93 - Indole Building Blocks

Oseka, Maksim et al. published their research in Organic Letters in 2016 | CAS: 112656-95-8

7-Nitroindoline-2,3-dione (cas: 112656-95-8) belongs to indole derivatives. The indole subunit is an almost ubiquitous component of biologically active natural products, and its study has been the focus of research for decades. More than 200 indole derivatives have already been marketed as drugs or are under advanced stages of clinical trials.Synthetic Route of C8H4N2O4

Asymmetric Organocatalytic Wittig [2,3]-Rearrangement of Oxindoles was written by Oseka, Maksim;Kimm, Mariliis;Kaabel, Sandra;Jarving, Ivar;Rissanen, Kari;Kanger, Tonis. And the article was included in Organic Letters in 2016.Synthetic Route of C8H4N2O4 This article mentions the following:

A highly enantioselective organocatalytic [2,3]-rearrangement of oxindole derivatives is presented. The reaction was catalyzed by squaramide, and this provides access to 3-hydroxy 3-substituted oxindoles I and II (Ar = Ph, 4-ClC₆H₄, 3-ClC₆H₄, 2-ClC₆H₄, 4-MeOC₆H₄, 4-NO₂C₆H₄, 2-thienyl, 2-naphthyl, etc.; R¹ = H, 5-F, 7-F, 5-MeO, 5-Br, 7-NO₂, etc.; R² = H, Bn, Me, i-Pr, 4-MeC₆H₄CH₂) in high enantiomeric purities. In the experiment, the researchers used many compounds, for example, 7-Nitroindoline-2,3-dione (cas: 112656-95-8Synthetic Route of C8H4N2O4).

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

Coyle, Robert et al. published their research in Journal of Organic Chemistry in 2014 | CAS: 6639-06-1

3-(1H-Indol-1-yl)propanoic acid (cas: 6639-06-1) 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. 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.Category: indole-building-block

Tandem Reactions via Barton Esters with Intermolecular Addition and Vinyl Radical Substitution onto Indole was written by Coyle, Robert;McArdle, Patrick;Aldabbagh, Fawaz. And the article was included in Journal of Organic Chemistry in 2014.Category: indole-building-block This article mentions the following:

A one-pot initiator-free Barton ester decomposition with tandem radical addition onto alkyl propiolates or phenylacetylene with aromatic substitution of the resultant vinyl radical allows convenient access to new 9-substituted 6,7-dihydropyrido[1,2-a]indoles, e.g., I (X = Me, CHO, CN; R = Me, Et, t-Bu). Pr radical cyclizations compete when forming the expanded 7,8-dihydro-6H-azepino[1,2-a]indole system. 2-Thiopyridinyl S-radical is incorporated into aromatic adducts when using unsubstituted indole-1-alkanoic acid precursors. X-ray crystallog. on substitution products allows selectivity of the radical addition onto less reactive internal alkynes to be determined In the experiment, the researchers used many compounds, for example, 3-(1H-Indol-1-yl)propanoic acid (cas: 6639-06-1Category: indole-building-block).

Nie, Guihua et al. published their research in Organic Chemistry Frontiers in 2021 | CAS: 774-47-0

5,6-Difluoroindoline-2,3-dione (cas: 774-47-0) belongs to indole derivatives. Indole, first isolated in 1866, and it is commonly synthesized from phenylhydrazine and pyruvic acid, although several other procedures have been discovered.Indole was synthesized in moderate yield via an o-naphthoquinone catalyzed tandem cross-coupling of substituted aniline and benzylamine under aerobic oxidation conditions.SDS of cas: 774-47-0

Umpolung of donor-acceptor cyclopropanes via N-heterocyclic carbene organic catalysis was written by Nie, Guihua;Huang, Xuan;Wang, Zhongyao;Pan, Dingwu;Zhang, Junmin;Chi, Yonggui Robin. And the article was included in Organic Chemistry Frontiers in 2021.SDS of cas: 774-47-0 This article mentions the following:

A N-heterocyclic carbene-catalyzed (NHC) formal umpolung of donor-acceptor (D-A) cyclopropanes was disclosed. The cyclopropane moiety was connected to an acetyl aldehyde that could be activated by a carbene catalyst. The initially electrophilic carbon attached to the donor group of the D-A cyclopropane aldehyde was inverted to form a nucleophilic reaction center. A subsequent reaction with isatins via a formal [3 + 2] process formed lactones I [R = H, 4-Br, 5-Me, etc.; R¹ = Bn, trityl; R² = OMe, OEt, O(i-Pr), OBn] bearing multiple functional groups with excellent enantio- and diastereoselectivities. In the experiment, the researchers used many compounds, for example, 5,6-Difluoroindoline-2,3-dione (cas: 774-47-0SDS of cas: 774-47-0).

Terent’ev, A. P. et al. published their research in Zhurnal Obshchei Khimii in 1959 | CAS: 3484-23-9

2-Methyl-6-nitro-1H-indole (cas: 3484-23-9) belongs to indole derivatives. Indole, first isolated in 1866, and it is commonly synthesized from phenylhydrazine and pyruvic acid, although several other procedures have been discovered. 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: 3484-23-9

Introduction of substituents into the benzene ring of indole. IV. Preparation of bromo-, nitro-, and aminoindoles and indolines was written by Terent’ev, A. P.;Preobrazhenskaya, M. N.;Bobkov, A. S.;Sorokina, G. M.. And the article was included in Zhurnal Obshchei Khimii in 1959.SDS of cas: 3484-23-9 This article mentions the following:

To 100 ml. concentrated H₂SO₄ was added dropwise at 5° 11.9 g. indoline, followed by 4.4 ml. HNO₃ (d. 1.5) in 100 ml. concentrated H₂SO₄ added at below 0°; after 1 hr. the mixture was quenched on ice to yield 100% 6-nitroindoline (I), m. 66.5-7.5° (ligroine); refluxing with Ac₂O gave the 1-Ac derivative, m. 154.5-5.0°. Refluxing 6.1 g. I and 9.1 g. chloranil in 300 ml. xylene 5 hrs. gave after treatment with aqueous NaOH 82% 6-nitroindole (II), m. 141-2°. Similarly, 6-nitro-2-methylindoline gave 81% 6-nitro-2-methylindole (III), m. 113.5-14.5°. Heating 1.3 g. II in 100 AcOH with 1.5 g. CrO₃ in 10 ml. H₂O 0.5 hr. on a steam bath gave 45% 6-nitroisatin, decomposing 300°; phenylhydrazone decomposed 265-6°. Similarly, III was oxidized in 1 hr. to 33% 4-nitro-2-acetamidobenzoic acid, m. 225-6°. Nitration of 5-bromo-1-methylindoline with HNO₃-H₂SO₄ at below 0° in 1 hr. gave 100% red 6-nitro-5-bromo-1-methylindoline, m. 73-4°, which heated with chloranil as above gave 54% yellow 6-nitro-5-bromo-1-methylindole, m. 167-8°. Nitration of indoline in Ac₂O with fuming HNO₃ at 10-12° gave a solid acetyl derivative of 5-nitroindoline which refluxed 0.5 hr. with concentrated HCl gave yellow 5-nitroindoline (IV), 74%, m. 91-1.5°, and a little less soluble dinitroindoline, m. 243-4°. Similarly, 2-methylindoline gave 63% 5-nitro-2-methylindoline, m. 78-9°. IV with chloranil as above gave in 10 hrs. 68% 5-nitroindole, m. 135-7°. 5-Nitro-2-methylindoline similarly gave 65% 5-nitro-2-methylindole, m. 171.5-2.5°. Oxidation of 5-nitroindole in AcOH with CrO₃-H₂O 1 hr. gave 5-nitro-2-aminobenzoic acid, decomposing 275.2-6.0°, which refluxed 1 hr. with 50% H₂SO₄ gave p-nitroaniline. To 5.4 g. 5-nitroindole in 50 ml. EtOH was added a little Raney Ni followed by dropwise addition of 100 ml. N₂H₄.H₂O over several hrs. at reflux; the filtered solution gave 82% 5-aminoindole, b₆ 190°, decomposing 129-30°; Bz derivative m. 166-7°. Similar reduction of 5-nitro-2-methylindole gave 76% 5-amino-2-methylindole, m. 156-6.5°; Bz derivative m. 192-2.5°. Similarly, 6-nitro-2-methylindole gave 43% 6-amino-2-methylindole, b₄ 170-7°, m. 84-5°; Bz derivative m. 210°. 6-Nitroindole gave 77% 6-aminoindole, b₁ 138°, m. 67-8°; Ac derivative m. 269-71°. Heating 6-nitro-1-acetylindoline (3.8 g.) with 30 g. SnCl₂ in 20 ml. concentrated HCl 25 min. on a steam bath gave after addition of NaOH 89% 6-amino-1-acetylindoline, m. 179-9.5°. Reduction of 6-nitro-2-methylindoline with N₂H₄ as above gave 91% yellow 6-amino-2-methylindoline, b₁₇ 175-80°, m. 61-2°; HCl salt, decomposed 230-5°. Similarly, 5-nitroindoline gave 97% 5-aminoindoline, m. 678.5°, whose diacetyl derivative, m. 211-12.5°. Similarly was prepared 93% 5-amino-2-methylindoline, b₉ 155-8°, m. 92°. Bromination of 2-methylindoline with Br in AcOH in the presence of H₂SO₄ gave in 1 hr. 63.5% 5-bromo-2-methylindoline (V), b₃ 130-45° (some decomposition) crude, b₃ 132-3.5°, d₂₀ 1.4550, n_D²⁰ 1.6085; Bz derivative m. 157°. Similarly, indoline gave 72.7% 5-bromoindoline, b₂ 114-14.5°, 1.5240, 1.6311; Ac derivative m. 119-19.5°. V and chloranil, as above, gave 54% 5-bromo-2-methylindole, b₄ 155-62° (some decomposition), m. 97-8°; this with formalin and aqueous Me₂NH in AcOH gave 5-bromo-2-methylskatyldimethylamine, m. 145-7°. 5-Bromoindoline and chloranil gave 47% 5-bromoindole, m. 92-3°. Cf. Colo, et al., C.A. 49, 14733a. In the experiment, the researchers used many compounds, for example, 2-Methyl-6-nitro-1H-indole (cas: 3484-23-9SDS of cas: 3484-23-9).

Ma, Zhenhui et al. published their research in Nano Research in 2019 | CAS: 4769-96-4

6-Nitro-1H-indole (cas: 4769-96-4) belongs to indole derivatives. The indole subunit is an almost ubiquitous component of biologically active natural products, and its study has been the focus of research for decades. 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). Electric Literature of C8H6N2O2

Magnetically recyclable Sm₂Co₁₇/Cu catalyst to chemoselectively reduce the 3-nitrostyrene into 3-vinylaniline under room temperature was written by Ma, Zhenhui;Liu, Hu;Yue, Ming. And the article was included in Nano Research in 2019.Electric Literature of C8H6N2O2 This article mentions the following:

Using non-noble metal catalysts to chemoselectively reduce the 3-nitrostyrene into 3-vinylaniline is extremely attractive due to the important applications of aromatic amines. However, the separation and recycle of catalytic particles to sustainably catalyze are still challenging on account of their small size. In this communication, we report a novel magnetically recyclable catalyst of Sm₂Co₁₇/Cu to chemoselectively reduce 3-nitrostyrene into 3-vinylaniline by activating ammonia borane (AB) to yield hydrogen. The Sm₂Co₁₇, composited of 180 nm Sm₂Co₁₇ nanomagnet and 10 nm Cu catalyst nanoparticles, shows a high conversion (98%) and a high selectivity (99%) for 3-nitrostyrene under ultrasonic concussion. More importantly, they are easily collected by self-separation method without any magnetic field. As a consequence, the excellent recyclable feature is acquired even underwent 10 cycles. Our approach provides a green strategy to synthesize magnetically recyclable catalysts. In the experiment, the researchers used many compounds, for example, 6-Nitro-1H-indole (cas: 4769-96-4Electric Literature of C8H6N2O2).

Ma, Bingqing et al. published their research in Journal of Fluorine Chemistry in 2015 | CAS: 4769-96-4

6-Nitro-1H-indole (cas: 4769-96-4) belongs to indole derivatives. Indole could be stereoselectively alkylated with chiral cyclopentyl sulfone reagent. 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.Name: 6-Nitro-1H-indole

BrOsted acid-catalyzed electrophilic trifluoromethylthiolation of indoles using thermally stable trifluoromethylthiolating reagent was written by Ma, Bingqing;Shao, Xinxin;Shen, Qilong. And the article was included in Journal of Fluorine Chemistry in 2015.Name: 6-Nitro-1H-indole This article mentions the following:

A BrOsted acid-catalyzed electrophilic trifluoromethylthiolation of indoles under mild conditions is described. The reaction was insensitive to moisture and oxygen, that should allow for easy handling. In addition, the reaction is compatible with a variety of functional groups. In the experiment, the researchers used many compounds, for example, 6-Nitro-1H-indole (cas: 4769-96-4Name: 6-Nitro-1H-indole).

Oseka, Maksim et al. published their research in Organic Letters in 2016 | CAS: 112656-95-8

Coyle, Robert et al. published their research in Journal of Organic Chemistry in 2014 | CAS: 6639-06-1

Ranasinghe, Nadeesha et al. published their research in Bioorganic & Medicinal Chemistry Letters in 2013 | CAS: 167631-84-7

Methyl 5-fluoro-1H-indole-2-carboxylate (cas: 167631-84-7) 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 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). Safety of Methyl 5-fluoro-1H-indole-2-carboxylate

Extending the versatility of the Hemetsberger-Knittel indole synthesis through microwave and flow chemistry was written by Ranasinghe, Nadeesha;Jones, Graham B.. And the article was included in Bioorganic & Medicinal Chemistry Letters in 2013.Safety of Methyl 5-fluoro-1H-indole-2-carboxylate This article mentions the following:

Microwave, flow and combination methodologies were applied to the synthesis of a number of substituted indoles. Based on the Hemetsberger-Knittel (HK) process, modifications allow formation of products rapidly and in high yield. Adapting the methodol. allows formation of 2-unsubstituted indoles and derivatives, and a route to analogs of the antitumor agent PLX-4032 is demonstrated. The utility of the HK substrates is further demonstrated through bioconjugation and subsequent ring closure and via Huisgen type [3+2] cycloaddition chem., allowing formation of peptide adducts which can be subsequently labeled with fluorine tags. In the experiment, the researchers used many compounds, for example, Methyl 5-fluoro-1H-indole-2-carboxylate (cas: 167631-84-7Safety of Methyl 5-fluoro-1H-indole-2-carboxylate).

Wu, Ge et al. published their research in Organic Letters in 2013 | CAS: 827-01-0

5-Chloroindole-3-carboxaldehyde (cas: 827-01-0) 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. 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.Computed Properties of C9H6ClNO

Regio- and Stereoselective Direct N-Alkenylation of Indoles via Pd-Catalyzed Aerobic Oxidation was written by Wu, Ge;Su, Weiping. And the article was included in Organic Letters in 2013.Computed Properties of C9H6ClNO This article mentions the following:

With two different sets of Pd catalyst systems in hand, indoles, whether bearing a C3-substituent or not, can be directly alkenylated on their nitrogen atoms using a sterically and electronically diverse array of alkenes, in which the high regio- and stereoselectivity are dependent on the nature of the alkenes used. This process proceeds in generally good yields and is compatible with a broad range of functional groups. Thus, a large series of N-alkenylated indoles, e.g., I, has been prepared In the experiment, the researchers used many compounds, for example, 5-Chloroindole-3-carboxaldehyde (cas: 827-01-0Computed Properties of C9H6ClNO).