Zirconium oxide nano-catalyzed synthesis of pharmacologically important bis(indolyl)methanes: a highly efficient and mild approach

We report herein a highly efficient and mild approach for synthesizing pharmacologically active bis(indolyl)methanes 3a-z, utilizing ZrO2 nanoparticles as a catalyst. The method involves a condensation reaction between indole and diverse aromatic aldehydes in acetonitrile under mild conditions. The ZrO2 nano-catalyst prepared via a co-precipitation method demonstrates exceptional efficacy, leading to favourable yields of the target bis(indolyl)methanes 3a-z. The versatility of this methodology is highlighted through substrate screening, showcasing its applicability to various aromatic aldehydes.

Clay-Mediated Reaction of Indoles with Cyclohexane-1,3-Diones: An Expedient Route to Indolylcyclohexenones

Indoles (1a–e) react with cyclohexane-1,3-diones (2a–c) on montmorillonite K10 clay at 60–70 °C to furnish the corresponding 3-(3′-indolyl)cyclohex-2-en-1-ones (5a–e, 6a–e, 7b–e) in 27–75% yields in 2.5–4 h.

Non-redox metal ion promoted oxidative coupling of indoles with olefins by the palladium(ii) acetate catalyst through dioxygen activation: experimental results with DFT calculations

Non-redox metal ions can sharply improve the Pd(ii)-catalyzed oxidative coupling of indoles with acrylates, leading to one-step synthesis of bis(indolyl)methane derivatives.

Synthesis, characterization and photophysical properties of some 3,3′-bisindolyl(aryl)methanes

A series of 3,3′-bisindolyl(aryl)methanes were synthesized and fully characterized by a combination of¹H and¹³C NMR spectroscopy and in one case using X-ray crystallography.

Synthesis, biological evaluation, and docking studies of novel thiourea derivatives of bisindolylmethane as carbonic anhydrase II inhibitor

This article describes discovery of 29 novel bisindolylmethanes consisting of thiourea moiety, which had been synthesized through three steps. These novel bisindolylmethane derivatives evaluated for their potential inhibitory activity against carbonic anhydrase (CA) II. The results for in vitro assay of carbonic anhydrase II inhibition activity showed that some of the compounds are capable of suppressing the activity of carbonic anhydrase II. Bisindoles having halogen at fifth position showed better inhibitory activity as compared to unsubstituted bisindoles. Derivatives showing inhibition activity docked to further, understand the binding behavior of these compounds with carbonic anhydrase II. Docking studies for the active compound 3j showed that nitro substituent at para position fits into the core of the active site. The nitro substituent of compound 3j is capable of interacting with Zn ion. This interaction believed to be the main factor causing inhibition activity to take place.

One-pot total synthesis of streptindole, arsindoline B and their congeners through tandem decarboxylative deaminative dual-coupling reaction of amino acids with indoles

This paper described a decarboxylative deaminative dual-coupling reaction of amino acids with indoles to afford BIM scaffolds and its further application to the one-pot total synthesis of natural products.

Evaluation of bisindole as potent β-glucuronidase inhibitors: synthesis and in silico based studies

Bisindole analogs 1-17 were synthesized and evaluated for their in vitro β-glucuronidase inhibitory potential. Out of seventeen compounds, the analog 1 (IC50=1.62±0.04 μM), 6 (IC50=1.86±0.05 μM), 10 (IC50=2.80±0.29 μM), 9 (IC50=3.10±0.28 μM), 14 (IC50=4.30±0.08 μM), 2 (IC50=18.40±0.09 μM), 19 (IC50=19.90±1.05 μM), 4 (IC50=20.90±0.62 μM), 7 (IC50=21.50±0.77 μM), and 3 (IC50=22.30±0.02 μM) showed superior β-glucuronidase inhibitory activity than the standard (d-saccharic acid 1,4-lactone, IC50=48.40±1.25 μM). In addition, molecular docking studies were performed to investigate the binding interactions of bisindole derivatives with the enzyme. This study has identified a new class of potent β-glucouronidase inhibitors.

Benzylic substitution of gramines with boronic acids and rhodium or iridium catalysts

Gramine-MeI salts were useful starting materials for the synthesis of 3-benzyl- and 3-allylindoles by the 1,4-addition of boronic acids to the C=C-C=N linkages generated in situ under Rh(I)-catalysis. On the other hand, under Ir(I) catalysis, the reaction of gramines with indoles was used to produce nonsymmetrical diindolylmethanes. [reaction: see text]

Green Protocol for Synthesis of Bis-indolylmethanes and Bis-indolylglycoconjugates in the Presence of Iron(III) Fluoride as a Heterogeneous, Reusable, and Eco-Friendly Catalyst

An efficient method for the preparation of bis-indolylmethanes and bis-indolylglycoconjugates from carbonyl compounds with indoles in the presence of a catalytic amount of iron(iii) fluoride under solvent-free conditions is reported. The desired products were obtained in high yields with a simple and environmentally benign procedure. The use of iron(iii) fluoride is feasible because of its stability, easy handling, easy recovery, reusability, and good activity.

A mild and environmentally friendly scandium(III) trifluoromethanesulfonate-catalyzed synthesis of bis(3'-indolyl)alkanes and bis(3'-indolyl)-1-deoxyalditols

Bis(3'-indolyl)alkanes and bis(3'-indolyl) derivatives containing a 1-deoxyalditol moiety were synthesized in the presence of 5 mol% of scandium(III) trifluoromethanesulfonate [Sc(OTf)3] in CH3CN or EtOH-H2O mixture as a solvent from room temperature to 70 degrees C in good yields (78-97%).

An analytical perspective on favoured synthetic routes to the psychoactive tryptamines

Many tryptamine derivatives are known to induce altered states of consciousness and are increasingly of interest in forensic and neurobiological studies. The analytical chemistry of certain synthetic routes to the tryptamines is discussed and likely side products and impurities identified, where literature reports are available. Recent examples from the authors' laboratory are presented to highlight future prospects and implications for analytical procedures. The aim of this review is to provide the analytical chemist with the foundation chemistry and some analytical targets to be able to undertake direct characterisation of products and intermediates. These might become available from interdiction of clandestine operations in a forensic environment or during the synthesis of the tryptamines for investigative neurobiological and clinical procedures.