Synthesis of Blue Emissive Quaternary 9,9-Disubstituted N-Methyl-7-azaindole-Appended (Phenylethynyl)-fluorene Derivatives.

A highly functionalized 9,9-disubstituted (phenylethynyl)-fluorene-appended N-methyl-7-azaindole derivatives has been synthesized from various fluorene propargylic alcohols and substituted-7-azaindoles using BF3OEt2 as a catalyst. The scope of the reaction was demonstrated by selecting a range of fluorene propargylic alcohols and substituting 7-azaindoles. A plausible reaction mechanism for forming title compounds via propargylic carbocation is postulated. The synthetic transformation of the products has been demonstrated by the Suzuki coupling and Click reaction. The Suzuki coupled compounds 5a-5e were evaluated for photophysical properties such as absorption, solvatochromism, emission, and Stokes shift and found blue emissive in nature.

Synthesis of 5-aryl-3,3'-bis-indolyl and bis-7-aza-indolyl methanone derivatives from 5-bromo-7-azaindoles via sequential methylenation using microwave irradiation, CAN oxidation, and Suzuki coupling reactions.

A catalyst-free and green chemical method has been developed for the methylenation of indole and N-methyl-7-aza indoles with aqueous formaldehyde afforded respective N,N'-dimethyl-3,3'-bis-7-azaindolylmethanes under microwave irradiation in excellent yield. Subsequent oxidation of the products thus obtained, using one electron chemical oxidant CAN afforded N,N'-dimethyl-3,3'-bis-7-azaindolylmethanone derivatives in excellent yield. This resulted in methanone derivatives with halogen substitution at the aryl ring which when subjected to Suzuki coupling with aryl boronic acids furnished highly functionalized fluorescent biaryl derivatives. Plausible mechanisms, characterization including XRD, and evaluation of photophysical properties of the Suzuki coupled products are described.

DMSO-allyl bromide: a mild and efficient reagent for atom economic one-pot N-allylation and bromination of 2°-aryl amines, 2-aryl aminoamides, indoles and 7-aza indoles.

A mixture DMSO-allyl bromide has been developed as a reagent for an atom economic one-pot N-allylation and aryl bromination under basic conditions. Utilizing this reagent, N-allylation-bromination of a number of 2°-aryl amines, aryl aminoamides, indoles, and 7-aza indoles has been achieved. The scope of the substrates and limitations, the synthetic utility of the products, and a plausible reaction mechanism have been proposed.

Chromone, A Privileged Scaffold in Drug Discovery: Developments in the Synthesis and Bioactivity.

Chromones are the class of secondary metabolites that broadly occur in the plant kingdom in a noticeable quantity. This rigid bicyclic system has been categorized "as privileged scaffolds in compounds" in medicinal chemistry. Their wide biological responses have made them an important moiety in a drug discovery program. This review provides updates on the various methods of synthesis of chromones and biological applications in medicinal chemistry. Various synthetic strategies for the construction of chromones include readily available phenols, salicylic acid and its derivatives, ynones, chalcones, enaminones, and 2-hydroxyarylalkylketones as starting materials. Synthesis of chromones by using metal, metal-free, nanomaterials and different other catalysts is herein included. Details of diverse biological activities of chromone derviatives, such as anti-cancer, antimicrobial, anti-viral, anti-inflammatory, antioxidant, as Monoamine Oxidase-B (MAO-B) inhibitors, anti- Alzheimer's agents, anti-diabetic agents, having antihistaminic potential, and acting as antiplatelet agents, are discussed.

Microwave-Assisted N-Allylation/Homoallylation-RCM Approach: Access to Pyrrole-, Pyridine-, or Azepine-Appended (Het)aryl Aminoamides.

A facile and diversity-oriented approach has been developed for the synthesis of pyrrole-, pyridine-, or azepine-appended (het)aryl aminoamides via the N-allylation/homoallylation-ring-closing metathesis (RCM) strategy. Microwave condition was efficiently utilized for N-allylation of (het)aryl aminoamides to synthesize di-, tri-, and tetra-allyl/homoallylated RCM substrates in good yields. All of the RCM substrates were successfully converted to respective pyrroles 6a-h, 13a,b, 15a,b, pyridines 11a-d, 13c, and azepines 7a,b via RCM. All of the five-, six-, and seven-membered N-heterocycles were synthesized in shorter reaction times with excellent yields without isomerization products. A one-pot reaction to synthesize compounds 6a and 6b without isolating corresponding RCM substrates was achieved successfully. The synthetic utility of the compound 6b has been demonstrated by synthesizing biaryl derivatives 17a,b under the microwave Suzuki coupling reaction condition.

1,3-Aminoalkoxylation and phenolation/dimerization of maleimide-derived Morita-Baylis-Hillman adduct of isatin via domino azidation-Michael addition/aza-Diels-Alder reaction.

NaN3-ROH/ArOH has been found to be an efficient reagent for 1,3-amino alkoxylation and 1,3-amino phenolation of a maleimide-derived MBH adduct of isatin via domino azidation-Michael addition. Following this protocol, with NaN3-formalin, a one-pot synthesis of 3-spiro-1,2-dihydropyrrolooxazine-5,7-dione-oxindole has been achieved. In an aprotic medium, the reaction underwent an unusual amino dimerization via an aza-Diels-Alder reaction of a common allylic imine intermediate.

Unprecedented one-pot, domino tertiary alcohol protection-Michael type addition of halides to Morita-Baylis-Hillman adduct of isatin with RCOX/K2CO3: diastereoselective synthesis of oxindole appended ß-halo esters.

A facile method utilizing RCOX/K2CO3 as a novel reagent for conjugate addition of hydrogen halide, in addition to tertiary (3°)-hydroxyl protection that leads to the synthesis of functionalized ß-halo Morita-Baylis-Hillman ester appended oxindoles, has been developed. The diastereoselective one-pot O-acylation-hydrohalogenation observed cannot otherwise be performed by treatment with hydrohalide. Deprotection of a 3°-hydroxyl protecting group has also been demonstrated by treatment with hydrochloric acid.

Census of cultivable bacterial community in common effluent treatment plant (CETP) of tannery discharge and computational scrutiny on their leading residents.

UNLABELLED: Common effluent treatment plant (CETP) for tannery effluent, is the combination of physical, chemical and biological treatment to facilitate the degradation of industrial waste water. Obviously, the biomass which survives in this extreme environment may have the ability to utilize the effluent as the sole carbon source for its survival. The ultimate aim of the present investigation is to expose the microbial diversity in each stage of the CETP through the culture dependent way. Bacterial diversity in the effluent were analysed through 16S rRNA gene. The community study revealed the dominance of firmicutes and the dominant genus was Bacillus sp, with variable species diversity. Notably, Putative Bacillus sp, B. firmus and B. licheniformis were observed in all stages of treatment. The dominant residents were analysed by BProm and TF site scan to prove their uniqueness. This species richness indicates the capability of liveliness in treatment plant and whose can be exploited for treating the effluent by using modern molecular approach. ABBREVIATIONS: CETP - Common Effluent Treatment Plant, PTIET - Pallavaram Tanners Industrial Effluent Treatment Company Ltd.

Unprecedented binary Cu(I)/Cu(II) catalyzed one-pot, three-component synthesis and evaluation of luminescent property of 2-amino-3-iminoethenylidene-2-indolones: a new class of merocyanine dye analogues.

A facile and efficient binary Cu(I)/Cu(II) catalyzed one-pot, three-component synthesis of 2-amino-3-iminoethenylidene-2-indolones in excellent yield has been achieved. Remarkably, these newly synthesized, stable merocyanine dye analogues showed strong luminescence in the blue region with large Stokes shifts.

Activated alkene dependent one-pot, three-component aza-Morita-Baylis-Hillman reaction of ferrocenealdehyde: synthesis of highly functionalized diverse ferrocene derivatives.

Activated alkene dependent one-pot, three-component aza-Morita-Baylis-Hillman (aza-MBH) reaction of ferrocenealdehyde afforded simple aza-MBH adduct of ferrocenealdehyde, unusual piperidine, ß-amino acid residue, and γ-ketoester derivatives of ferrocene in good yield. The synthetic protocol with MVK has led to an unexpected ferrocenyl piperidine derivative in an excellent yield via diastereoselective domino aza-Michael/double Aldol pathway. Plausible mechanisms for the formation of unusual products and diastereoselectivity have also been described. The products can be used for the concise synthesis of ferrocenyl nitrogen heterocycles and bioconjugates.

An efficient stereoselective synthesis of 3-spirocyclopentene- and 3-spiropyrazole-2-oxindoles via 1,3-dipolar cycloaddition reaction.

The chemistry phosphorus and sulfur ylides have been exploited for a facile, short and efficient synthesis of 3-spirocyclopentene- and 3-spiropyrazole-2-oxindoles from E- and Z-isomers of bromo derivatives of Morita-Baylis-Hillman adducts of isatin with Ph(3)P/activated alkene/K(2)CO(3) and Me(2)S/DEAD/K(2)CO(3), respectively, via [3 + 2]-annulation strategy.

Pyridine core activation via 1,5-electrocyclization of vinyl pyridinium ylides generated from bromo isomerized Morita-Baylis-Hillman adduct of isatin and pyridine: synthesis of 3-spirodihydroindolizine oxindoles.

An activation of the pyridine nucleus has been achieved via 1,5-electrocyclization of vinyl pyridinium ylides generated from bromo isomerized Morita-Baylis-Hillman adducts of isatin and pyridine under basic conditions. The method has been successfully applied for an efficient synthesis of a number of 3-spirodihydroindolizine-2-oxindoles, which have been found as core structure of secoyohimbane and heteroyohimbane alkaloid natural products.

Synthesis of novel functionalized 3-spiropyrrolizidine and 3-spiropyrrolidine oxindoles from Baylis-Hillman adducts of isatin and heteroaldehydes with azomethine ylides via [3+2]-cycloaddition.

A novel regioselective synthesis of a number of functionalized 3-spiropyrrolizidine and 3-spiropyrrolidine oxindoles from Baylis-Hillman adducts of isatin and heteroaldehydes via [3+2] cycloaddition of azomethine ylides in excellent yields has been reported.

R3Al-R'3SiOTf: novel and powerful reagent system for stereospecific alkylation-silylation reactions of epoxides.

[reaction: see text] A novel and powerful reagent system R(3)Al-R'(3)SiOTf for the one-pot alkylation-silylation reaction of epoxides was discovered, and the reactions of various epoxides with the new reagent system have been demonstrated to occur stereospecifically giving rise to the corresponding alkylation-silylation products in excellent yields.