The unexpected formation of 5,6-dihydrobenzo[1,7]phenanthroline instead of 5,6-dihydrobenzo[1,7]phenanthroline-3-carbonitrile in acridine molecules using Michael addition has been observed for the first time.

Mohana Roopan S

Department of Chemistry

School of Advanced Sciences

Vellore Campus

Bharathi A

Palaniraja J

Anand K

Gengan R.M.

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

RSC Advances

Several synthetic routes have been achieved to synthesize pyrane fused systems. As a follow up of earlier work, we hereby report the microwave assisted synthesis of key intermediate, pyrane fused acridine compounds 3a–f. It was obtained by treating α,β-unsaturated ketone 1a–f and malononitrile 2 in presence of piperidine with ethanolic solution at 50 C under 200 W power. This method also optimized via microwave method using RSM methodology. All the synthesized derivatives and target compounds were evaluated for cytotoxicity effect on human hepatoblastoma (HepG2) cell line and HDAC enzyme activity.

Fulltext

Proceedings

Microwave Assisted Synthesis and Its Cytotoxicity Study of 4H-Pyrano[2,3-a]acridine-3-carbonitrile Intermediate: Experiment Design for Optimization Using Response Surface Methodology

A series of imidazo-pyrimido fused acridines were synthesized and identified using conventional spectroscopic techniques. All the synthesized title compounds were subjected to in vitro antibacterial and insecticidal screenings. For insecticidal activity, the synthesized fused compounds are testing against two pests namely, Sitophilus oryzae (S. oryzae) and Callosobruchus maculatus (C. maculatus). For antibacterial screening, the compounds are testing against four bacteria, Bacillus subtilis (B. subtilis), Proteus mirabilis (P. mirabilis), Staphylococcus aureus (S. aureus) and Vibrio parahaemolyticus (V. parahaemolyticus). Notably, compound 8-(4-isopropylphenyl)-16-phenyl-6,7-dihydrobenzo[4′,5′]imidazo[1′,2′:1,2]pyrimido[4,5-a]acridine and 8-(2,4-dimethoxyphenyl)-16-phenyl-6,7-dihydrobenzo[4′,5′]imidazo[1′,2′:1,2]pyrimido[4,5-a]acridine were identified as the most promising applicant for further studies. © 2017 Elsevier B.V.

Journal of Molecular Liquids

Conventional spectroscopic identification of biologically active imidazo-pyrimido fused acridines: In vitro anti-bacterial and anti-feedant activity

A new and highly efficient microwave promoted N-alkylation of triazolo-quinazolinones was developed by treating various phenyl-substituted heterocyclic amines with benzyl chloride using K2CO3 as a base in the presence of DMF. Also the heterocyclic amines were synthesized by condensing the 3-amino-1,2,4-triazole substituted benzaldehydes and 1,3-cyclohexanedione in the presence of microwave irradiation under solvent free condition. The synthesized heterocycles 4a–o and 6a–o were further confirmed by using different spectroscopic techniques such as NMR and HRMS. The compounds 6a–o was studied for their solvatochromic property with increasing polarity of solvents. The determinations of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging effect of the scaffolds 6a–o were carried out by UV–Vis spectrometer. In terms of IC50 all the compounds have shown remarkable antioxidant property compared with Ascorbic acid. © 2016 Elsevier B.V.

Conventional spectroscopic identification of N-alkylated triazolo-quinazolinones and its antioxidant, solvatochromism studies

This study deals with a new and efficient metal-free regioselective synthesis of pyrimido-fused indazoles with nitrogen ring junction motifs. We have developed a metal-free domino type reaction between 3-aminoindazole, aryl aldehydes and aceotophenones in the presence of KOH/DMF that leads to pyrimido[1,2-b]indazole analogues. Response Surface Methodology (RSM) coupled with a Box-Behnken design (BBD) were utilized for exploring the effect of base used (A), temperature of reaction (B) and (C), reaction time. This approach can allow access to a variety of pyrimidoindazole fluorophores and related compounds. The compound N,N-dimethyl-4-(2-phenylpyrimido[1,2-b]indazol-4-yl)aniline (4e) displays the maximum fluorescence intensity at 518 nm and shows a fluorescence quantum yield of 0.068. The synthesized pyramido-fused indazoles have been evaluated for their free radical scavenging activity and compound 4f showed good antioxidant activity. © 2016 by the authors; licensee MDPI.

Molecules

A Metal-Free Regioselective Multicomponent Approach for the Synthesis of Free Radical Scavenging Pyrimido-Fused Indazoles and Their Fluorescence Studies

A non-conventional methodology has been utilized for the synthesis of a series of 1,2,4-triazolo-quinazoline-thiones (2a-l). Here the reaction was carried out between 1,2,4-triazolo-quinazolinones (1a-l), in the presence of 1,4-dioxane. The mixture was irradiated under microwave (100W) for 7min to obtain targeted molecules (2a-l). All the synthesized molecules were confirmed by (1)H, (13)C NMR and HRMS. The solvatochromic property (absorption spectra) of compounds (2a-l) in solvents of different polarities was studied. The compounds (2a-l) were further subjected for their in vitro free radical screening using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and also screened for their in vitro anti-fungal property against Aspergillus flavus (A. flavus) and Aspergillus niger (A. niger). The results from free radical scavenging assay showed promising activity for compounds 2a, e-i, whereas compound 2d showed significant antioxidant activity when compared to ascorbic acid. In vitro anti-fungal study showed that the 1,2,4-triazolo-quinazoline-thiones (2a-l) had significant activity against A. flavus and A. niger compared with widely used antifungal agent Fluconazole.

Journal of Photochemistry and Photobiology B: Biology

1,2,4-Triazolo-quinazoline-thiones: Non-conventional synthetic approach, study of solvatochromism and antioxidant assessment

Now a days a majority share of people undergoes through some health problems or mental stress. The reason for both may be many factors like unhealthy food habits, lack of doing body exercise, pressure from family and job environment etc. These factors can physically and mentally deteriorate the creativity and productivity of a person. Yoga can be considered as one of the finest solutions in this case though it refreshes both physically and mentally. Yoga transforms a person balanced with mental, physical and spiritual elements in the right composition. In this technology era, it will be good to integrate yoga with the trends of technology. This work proposes a scheme of integrating and monitoring yoga activities using the concept of Internet of Things (IoT) and a smart application. The body sensors (Pressure, temperature, humidity) attached with the person doing yoga senses relevant data and is processed using a central processor (Smart phone or smart devices) to provide necessary suggestions or feedbacks to the user. This work will provide a platform to the yoga practice person to monitor and review their yoga activities by themselves. Our research results claims that the various parameters like blood pressure, temperature and heart beat rate is improvised a lot after practicing yoga. Our survey results with the yoga persons doing this IoT based yoga system shows that our system is much helpful for the yoga persons to practice yoga efficiently and effectively.

International Journal of Intelligent Engineering and Systems

A Real Time Monitoring System for Yoga Practitioners

In general, aryl-aryl transformations were investigated via transition metal-catalysed reactions. However, transition metal-mediated organic synthesis provided higher yields but has some flaws such as high cost, and the need for careful exclusion of air and moisture during the reactions. Possibly, there may be contamination of the product from traces of heavy metals present. To overcome these kinds of disadvantages, continuous efforts have been focused on the recent development of aryl-aryl formation through transition metal-free (TMF) reactions. However, most of these cross-couplings reaction were limited to hetero and electron-rich arenes which require strong inorganic bases. Our critical review includes a synthetic pathway to prepared X-aryl (X = C, N, O and S) motif by a transition metal-free scenario. Formerly, TMF reactions were carried out by various sources like strong bases, diazodium salt, aryliodonium salt, organo-catalysts and versatile energy sources like microwave heating, visible light and photochemical reactor. In this review, we have focused on the transition metal-free arylations. © 2014 Springer Science+Business Media Dordrecht.

Research on Chemical Intermediates

Synthetic journey towards transition metal-free arylations

We report an expeditious synthesis of selected indazolo-quinazolinone derivatives via an iodine-mediated multi-component reaction (MCR).

Iodine-mediated synthesis of indazolo-quinazolinones via a multi-component reaction

Unexpected regiospecific Michael addition product: synthesis of 5,6-dihydrobenzo[1,7]phenanthrolines

A new series of substituted ethyl 10-chloro-4-(3,4-dimethoxyphenyl)-2-hydroxy-12-phenyl-1,4,5,6-tetrahydrobenzo[a]acridine-3-carboxylates, 3a-e have been synthesized through NaOH base mediated cyclocondensation of (E)-7-chloro-2-(3,4-dimethoxybenzylidene)-9-phenyl-3,4-dihydroacridin-1(2H)-ones, 1a-e with ethyl acetoacetate. Structures of these synthesized molecules were studied by FT-IR, 1H NMR, 13C NMR and EI-MS. And all the synthesized compounds were evaluated for their UV-absorption studies with various metal solutions. Acridine-3-carboxylate derivatives were tested against fourth instar larvae of Anopheles stephensi and Hippobosca maculata. Among those compounds, 3b and 3e have good larvicidal activities against both A. stephensi and H. maculata. Toxicity of compounds, 3b and 3e compounds were evaluated with the reference non-target aquatic species like, Sphaerodema annulatum Fabricius (Heteroptera: Belostomatidae) and Zyxomma petiolatum Rambur (Odonata: Libellulidae) results very low LC50values revels that, the synthetic compounds are non toxic. © 2014 Elsevier B.V. All rights reserved.

Journal	Data powered by TypesetRSC Advances
Publisher	Data powered by TypesetRoyal Society of Chemistry (RSC)
ISSN	20462069
Open Access	0