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An organic reaction with water as a medium has numerous benefits, like improvement in reactivities and selectivities, simple workup techniques, possibility of recycling the catalyst with milder reaction conditions and eco-friendly synthesis. Further, exploring of water as a reaction medium gives rise to unusual reactivities and selectivities, supplementing the organic chemist’s necessity for reaction media. This review focus on the use of water for the synthesis of Nitrogen-containing heterocycles covering from 2011 to 2021.

An efficient and facile synthesis of tri-indolylmethane derivatives in a deep eutectic solvent, starting from indoles and indole-3-carbaldehydes, is developed. This methodology offers several advantages, such as simple reaction procedures, use of an inexpensive and a recyclable solvent, and a high yield.

An efficient InCl3-catalyzed sequential reaction of aromatic amines, aromatic aldehydes and functionalized alkynes leading to the formation of new quinoline derivatives exhibiting significant fluorescence activities is described. The photophysical investigations of quinolines were carried out by absorption and photoluminescence measurements. One particular compound 4 h having maximum intensity, emitting green colour (Φ = 0.78) with average life time of 6.20 ns was the best amongst the tested compounds. The presence of the amino group at the 4-aryl substituent of the quinoline backbone played an important role in executing the Povarov cyclization successfully and enhancing the flourescence properties of the newly synthesized quinolines. Supplementary Information The online version contains supplementary material available at 10.1007/s10895-020-02647-3.

The leaf crude extract of

A small molecule library of trans-1,3-diaryl-1H-naphtho[1,2-e][1,3]oxazines 4 is synthesised through multicomponent reactions involving aliphatic amines, aromatic aldehydes and β-naphthol using a heterogeneous catalyst, SiO2.HClO4, and ethanol as the solvent. The anti-inflammatory activities of the synthesised compounds are evaluated together with in silico studies. 1,3-Bis(4-chlorophenyl)-2-ethyl-2,3-dihydro-1H-naphtho[1,2-e][1,3]oxazine (4h) shows the best activity with IC50 = 4.807 µg/mL in the heat-induced haemolysis, while 1,3-Bis(5-bromothiophen-2-yl)-2-ethyl-2,3-dihydro-1H-naphtho[1,2-e][1,3]oxazine (4c) shows significantly high anti-inflammatory activity (IC50 = 5.5 µg/mL) in comparison with standard drugs, such as sodium diclofenac. In addition, molecular docking simulation study confirms the in-depth molecular interaction of the two lead compounds, 4c and 4h with better binding affinities and docking scores at the active site of the COX-2 enzyme compared with diclofenac.

β-Ketodithioesters (KDEs) are versatile building blocks for the rapid construction of various heterocyclic compounds. Quite a good number of successful reactions based on KDEs have been developed in the past decade for the construction of heterocyclic skeletons under mild conditions. This review covers the new CC/ X bond formation and annulation reactions of KDEs with dielectrophilic or dinucleophilic reagents. Multicomponent reactions using KDEs to construct various heterocycles are also the major contents in this review. Objective: The aim of this review is to bring a fresh perspective on the application of KDEs in organic synthesis covering from 2013 to 2020. Conclusion: From this review, it has been cleared that KDEs have been the object of numerous studies on its use in heterocyclic synthesis. The presence of different functional groups on this synthon permits the incorporation of C-C/X sources into the final targets, which is the significant property of KDEs.

Leaf crude extract (aqueous) of Oroxylum indicum (L.) Kurz induces genomic DNA fragmentation, comet formation, and inhibition of cell proliferation in prostate cancer cell line, PC3 as assessed by agarose gel electrophoresis, comet assay, and MTT assay respectively. The bioactive compound was purified through bioassay-guided fractionation using preparative HPLC and MTT as-say. The brown and water-soluble compound was characterized using 1H and 13C nuclear magnetic resonance (NMR), fourier transform infrared (FT-IR) and electrospray ionization (ESI) mass spectrometry, and the compound was iden-tified as a glycosylated hydroquinone derivative, 2-[p-(2-Carboxyhydrazino)phenoxy]-6-(hydroxymethyl) tetrahy-dro-2H-pyran-3,4,5-triol (molecular formula, C13H18N2O8; molecular mass = 330). The identified phytocompound has not been reported earlier elsewhere. Therefore, the common name of the novel anticancer phytocompound isolated from oroxylum indicum in this current study is named as oroxyquinone. The half-maximal inhibitory concentration (IC50) of oroxyquinone on PC3 cells was 19.44 µg/ml (95% CI = 17.97 to 21.04). Oroxyquinone induced cell cycle arrest at S phases and inhibition of cell migration on PC3 as assessed by flow cytome-try and wound healing assay respectively. On investigating the molecular mechanism of inducing apoptosis, the results indicated that the oroxyquinone induced apoptosis through the p38 pathway and cell cycle arrest, however, not through caspase-3 and PARP pathways. The present study identifies a novel an-ticancer molecule and provides scientific evidence supporting the therapeutic potency of OI for ethnomedicinal uses.

Knoevenagel cyclocondensations of α-hydroxy naphthaldehyde with β-oxodithioesters and ketene dithioacetals yielded 2H-benzo[f]chromene-2-thiones and 2H-benzo[f]chromen-2-ones, respectively, in high yields. The newly synthesized compounds were evaluated for antifungal and antibacterial activities. Among them, compounds (2-furyl)(3-thioxo-3H-benzo[f]chromen-2-yl)methanone and phenyl(3-oxo-3H-benzo[f]chromen-2-yl)methanone exhibited excellent antifungal activity against tested fungi Curvularia lunata and Fusarium moniliforme. The highest antibacterial activity against the tested bacteria Escherichia coli and Staphylococcus aureus was observed for (4-chlorophenyl)(3-oxo-3H-benzo[f]chromen-2-yl)methanone. The results of antimicrobial screening demonstrate that (2-furyl)(3-thioxo-3H-benzo[f]chromen-2-yl)methanone, phenyl(3-oxo-3H-benzo[f]chromen-2-yl)methanone, and (4-chlorophenyl)(3-oxo-3H-benzo[f]chromen-2-yl)methanone are promising as antimicrobial drugs.

An efficient and facile synthesis of spirooxindole derivatives bearing pyrano[2,3-c]pyrazole moiety has been achieved using deep eutectic solvent (DES) promoting a four-component reaction. The protocol avoids the use of costly and toxic catalysts and organic solvents which encounters many side effects on the environment and human beings. The simplicity and versatility of this eco-friendly green method is described. Deep eutectic solvent (DES) promoted eco-friendly synthesis of spirooxindole derivatives involving a four-component reaction is described in this article. This procedure is highly sustainable because of the involvement of readily available and biodegradable deep eutectic solvent as a reaction medium and promoter.

An efficient one-pot multicomponent synthesis of 3-(2-(1H-indol-3-yl)ethyl)-4-hydroxy-4-arylthiazolidine-2-thione and 3-(2-(1H-indol-3-yl)ethyl)-4-arylthiazole-2(3H)-thione has been developed from a multicomponent reaction of tryptamine, carbon disulfide and phenacyl bromide. This protocol has an advantage such as operational simplicity, short reaction time, and affording good to excellent yields.

A novel and facile one-pot synthesis of 1-substituted tetrahydro-β-carbolines by cyclocondensation of ketene S,S–acetals with tryptamine in presence of InCl3 and TFA as co-catalysts by Bischler-Napieralski cyclization is described. The reaction involves formation of one C-N bond, one C-C bond and a new ring annulation over an indole moiety.

A new library of 24 carbazolyl glyoxamides 14a–x were designed and synthesized from glyoxalic acids and arylamines in the presence of HATU as a coupling reagent under MW irradiation. The synthesized carbazolyl glyoxamides were evaluated for their in vitro anticancer and antibacterial activities. Of the synthesized carbazolyl glyoxamides, compounds 14l and 14q exhibited the most potent cytotoxicity towards a breast cancer cell line with IC50 values of 9.3 and 9.8 μM, respectively. Further, caspase-3 assay for carbazolyl glyoxamides indicated that these compounds induced apoptotic cell death in Jurkat cells. Furthermore, some of the synthesized carbazolyl glyoxamides 14g, 14k, 14l and 14n exhibited comparable or even better antibacterial activity (MIC = 8–16 μg mL−1) than chloramphenicol against the selected bacterial strains.

Synthetic application of Silica–ZnCl2 , as an efficient and eco-friendly catalyst for the synthesis of a small library of dihydropyrimidinones is described in this report. The reaction involves a one pot, multicomponent reaction of β-oxodithiocarboxylates, aldehydes, and urea under solvent-free conditions. The experimental procedure is simple, environmental benign, tolerated with many functional groups, and results in good to excellent yield of the products.

We are reporting a simple, efficient and green protocol for the synthesis of chromenes and dihydropyrimidines (products of Knoevenagel and Biginelli reaction, respectively) by the use of silica-supported perchloric acid (HClO4–SiO2) as an effective heterogeneous catalyst. Short reaction times, high product yields, simple procedure and reusability of the catalyst are the superior characteristics of this protocol.

The indole scaffold is found in a wide range of bioactive heterocycles and natural products. Moreover, the indole moiety is considered as the active principle in several alkaloids such as mitomycin C and reserpine. Thus, over the past decade, chemists are increasingly attracted towards the studies on the pharmacological and therapeutic activities of indole containing compounds. Furthermore, the molecular structures of well-known drugs such as sumatriptan, tadalafil, fluvastatin and rizatriptan are based on indole frameworks. This mini-review covers some of the significant and recent achievements of indole derivatives with respect to their biological activities up to 2015.

Synthesis of Bis- and Tris Indolylketones Bull. Korean Chem. Soc. 2014, Vol. 35, No. 10 2951efficient, selective and mild method for the preparation ofβ,β-bisindolyl-ketones 4, tris-indolylketones 7 and meridi-anin derivatives 8 by treating α-oxoketene dithioacetals withindole in the presence of InCl

Convenient methods of synthesis of novel polyaza pyrimidines and polyaza pyrazoles have been described in this paper. The synthetic method is based on one-pot, three-component cyclocondensation of α-oxoketene dithioacetals, 2,6-diaminopyridine, and guanidine/hydrazine. Polyaza S,N-acetals have been generated in situ by treating α-oxoketene dithioacetals with 2,6-diaminopyridine in the presence of n-butyl lithium, which were subsequently treated with guanidine nitrate and hydrazine hydrate to afford polyaza pyrimidines and polyaza pyrazoles, respectively.

Polyaza α-oxoketene S,N-acetals can exist as either enamino or imino tautomeric forms. Based on the spectroscopic data and structural analysis of one of the S,N-acetals, the stereochemistry was unambiguously assigned as an all-E-configuration. The crystal structure confirms the enamino structure and shows extensive use of C-H⋯X (X = N, O, and S) weak hydrogen bonding interactions, thereby generating a 3-dimensional network in solid state.

The cycloannulation of β-oxodithioesters and tryptamine in dichloromethane in the presence of a catalytic amount of InCl3 and TFA gave the novel 5-aryl/heteroaryl 2a(1),9b-dihydro-1H-2a,5a-diaza-cyclopenta[jk]fluorene-3(2H)-thiones in moderate to good yields. The reaction was proposed to involve a tandem transformation of thioamide, protonation, and dehydrative cyclization. KMnO4-oxidation of these newly prepared compounds yielded oxidative desulfurization products in good yields.

Stannous chloride, an inexpensive mild Lewis acid has been used in various organic synthetic operations. It was used in reducing various functional groups in the earlier days. The recent trends however expanded the scope of its applications in organic synthesis using it as an efficient catalyst. This review highlights the catalytic potential of this rea- gent in a wide range of reactions such as allylation, propargylation, multicomponent reactions and syntheses of bioactive heterocycles.

Transesterification of β-oxodithioesters catalyzed by stannous chloride under solvent-free condition has been reported for the first time. The short reaction time and good to excellent yields using inexpensive catalysts are attractive features of this synthetic protocol.

A facile synthesis of chromene-2-thiones by the Pechmann condensation of phenols and β-oxodithioesters catalyzed by AlCl 3 under solvent-free condition has been reported. The best results were obtained in the case of substituted phenols such as resorcinol, substituted resorcinol, and pyrogallol. The optimum condition was observed with the use of 10 mol % of AlCl 3 at 130 °C under solvent-free conditions. This method offers a wide scope for the synthesis of coumarins in good yields during a short period of time.

An efficient one-pot multicomponent synthesis of 3-(2-(1H-indol-3-yl)ethyl)-4-hydroxy-4-arylthiazolidine-2-thione and 3-(2-(1H-indol-3-yl)ethyl)-4-arylthiazole-2(3H)-thione has been developed from a multicomponent reaction of tryptamine, carbon disulfide and phenacyl bromide. This protocol has an advantage such as operational simplicity, short reaction time, and affording good to excellent yields.

A novel and facile one-pot synthesis of 1-substituted tetrahydro-β-carbolines by cyclocondensation of ketene S,S–acetals with tryptamine in presence of InCl3 and TFA as co-catalysts by Bischler-Napieralski cyclization is described. The reaction involves formation of one C-N bond, one C-C bond and a new ring annulation over an indole moiety.

Synthetic application of Silica–ZnCl2 , as an efficient and eco-friendly catalyst for the synthesis of a small library of dihydropyrimidinones is described in this report. The reaction involves a one pot, multicomponent reaction of β-oxodithiocarboxylates, aldehydes, and urea under solvent-free conditions. The experimental procedure is simple, environmental benign, tolerated with many functional groups, and results in good to excellent yield of the products.

Department of Chemistry, Manipur University, Canchipur, Imphal 795003, Manipur, IndiaReceived August 1, 2012, Accepted September 3, 2012Here we report our recent result of a new semiconductor material, which has an asymmetric structure. Thesynthesized molecules consist of anthracene and thiophene connected by bridged ethylene and substituted withhexyl or dodecyl groups as pendants. The semiconductors were synthesized using a McMurry coupling reactionbetween anthracene-2-carbaldehyde and corresponding 5-hexyl(or dodecyl)thiophene-2-carbaldehyde. A firstinvestigation of synthesized asymmetry AVHT (9a) and AVDT (9b) for the physical properties showed thatthey have high oxidation potential and thermal stability. The devices prepared by using AVHT (9a) and AVDT(9b) showed the mobility of 2.6 × 10

A series of 2,3-dihydro-3-alkyl/aryl-2-thioxoquinazolin-4(1H)-one is prepared by one-pot multicomponent reaction of anthranilic acid, S,S-dimethyl trithiocarbonate and aliphatic/aromatic amine under solvent-free conditions.

Adhatoda vasica Nees (Acanthaceace) is a well known medicinal plant from which certain alkaloids, phenolics, flavonoids, sterols and their glycoside derivatives have been isolated. Its diverse medicinal activities include cardiovascu- lar protection, abortifacient, antitubercular, antimutagenic, antiulcer, antiasthmatic activities, hepatoprotective, antibacte- rial and antitussive activities. It is commonly used in indigenous and traditional folk medicine system in South-East-Asia. An up-to-date data on phytochemical compositions and pharmacological properties of different parts of Adhatoda vasica are reviewed and commented in this article. Adhatoda vasica Nees (synonym: Justicia adhatoda) (Fig. 1) of the Acanthaceae family is a well-known plant drug in Ayurvedic and Unani medicine (1) and the plant has been used in the indigenous system of medicine in India for more than 2000 years (2). It is commonly known as Malabar nut tree and local names in some areas are Ya-Zui-Hua in China, Vasaka (Sanskrit), Arusha (Hindi), Bakas (Bengali), Nongmangkha-agouba (Manipuri), Alduso (Gujarati), Adasaramu (Telugu), Adadodai (Tamil), Adusoge (Kannada) and Atalotakam (Malayalam) in India. green beneath. The leaves grow in an opposite formation, and are entirely lanceolate, and shortly petiolate, tapering towards both apex and base. The leaves become brownish- green when dry and taste bitter with a smell similar to strong tea. Its stem is soft and makes a good charcoal. The flowers are large, dense, terminal spikes with large, attractive white petals, streaked with purple on the lower lip. The fruit is a small, clavate, longitudinally channeled capsule, containing four globular seeds. 1.2. Distribution It is an evergreen shrub growing throughout Indo- Malayan region, Punjab in the North, and Bengal and Ma- nipur in the South-East to Tranvacore of Kerala, at an alti- tude of 1350 m. The plant is also seen distributed in Sri Lanka, Upper and Lower Myanmar, southern China, Laos, and the Malay- Peninsular and Indonesian Archipelago.

A highly efficient method of synthesis of S-allyl-N-aryl dithiocarbamates using SnCl2 as a catalyst under solvent-free conditions is described. The mild reaction conditions, high yields, and shorter reaction period illustrate the good synthetic utility of this method.

Many classical routes have been available for the synthesis of coumarin. The Pechmann reaction for the synthesis of coumarin involves the condensation of phenols with β-ketonic esters in the presence of variety of acidic condensing agents such as sul-furic acid, hydrochloric acid and phosphoric acid, phosphorous pentoxide, trifluoroacetic acid and Lewis acids such as ZnCl

The reactions of ketene dithioacetals with ethane-1,2-diamine, propane-1,3-diamine, 2-aminoethanol, 3-aminopropanol, and 2-aminoethanethiol in ordinary water in the absence of any acid/base catalyst afforded the heterocyclic ketene N,N-, N,O- and N,S-acetals in good yields.

Three blue light-emitting cyclopenta[def]phenanthrene-based conjugated polymers were synthesized using the Yamamoto coupling reaction and their optical, thermal, and electrochemical properties were examined. The results indicated that the number-average molecular weights of compounds 11, 12, and 13 were 16,400, 11,000, and 10,400, respectively. The polymers were soluble in common solvents, such as toluene, chloroform, etc. Their structures were confirmed using 1H NMR, mass, and FTIR spectroscopy. Homopolymer 11 showed stable blue emission with a photoluminescence peak at 408 nm in solution and at 456 nm in thin film form. Moreover, polymers 11, 12, and 13 exhibited high thermal stability up to 340°C, 333°C, and 380°C, respectively.

Regioselective allylation of enaminones using CuCl 2 as the catalyst to give C-allylated products is reported for the first time. The C-allylated products undergo hydrolysis followed by a rearrangement yielding β-keto allyl enamides in excellent yields.

Methyl 2-(substituted benzoylthio)benzoates undergo intramolecular ring cyclizations in the presence of Zn/TiCl 4 /LiAlH 4 to give the corresponding 2-aryl- or alkylsubstituted benzo-thiophenes in good yields.

Isolation of the methanol extract of Solanum xanthocarpum resulted in the isolation and characterization of carpesterol (1) and four steroidal glycosides (2, 3, 4, and 5). The structures of these compounds were established by spectroscopic analysis. The antifungal activity of the steroidal compounds extracted from the fruits of S. xanthocarpum was investigated against Aspergillus niger and Trichoderma viride. The isolated compounds 1, 2, 3, 4, and 5 exhibited inhibitory effects on the radial growth of A. niger and Trichoderma viride.

An efficient and convenient synthesis of substituted pyrazoles with aryl and heteroarylamino substituents attached to the C-3 and C-5 positions by the action of hydrazine hydrate on either ketene N,S-acetals or mixed N,N-aminals hydrate is reported.