A. Bharathi

Acaricidal, insecticidal, and larvicidal efficacy of aqueous extract of Annona squamosa L peel as biomaterial for the reduction of palladium salts into nanoparticles

In recent years the utilization of secondary metabolites from plant extract has emerged as a novel technology for the synthesis of various nanoparticles. In this paper we studied the potential of nanocrystalline palladium nanoparticles production using acaricidal, insecticidal and larvicidal efficacy of Annona squamosa L aqueous peel extract as the biomaterial for the first time. The synthesized nanoparticles were characterized and confirmed as palladium nanoparticles by using UV-visible spectroscopy, XRD and TEM analysis. The results clearly showed that the compounds containing -OH as a functional group played a critical role in capping the nanoparticles. Also the results highlight the possibility of green pathways to produce palladium nanoparticles.

Efficient phyto-synthesis and structural characterization of rutile TiO2 nanoparticles using Annona squamosa peel extract.

In the present study, the biosynthesis of rutile TiO(2) nanoparticles (TiO(2) NPs) was achieved by a novel, biodegradable and convenient procedure using fruit peel Annona squamosa aqueous extract. This is the first report on the new, simple, rapid, eco-friendly and cheaper methods for the synthesis of rutile TiO(2) NPs at lower temperature using agricultural waste. Rutile TiO(2) NPs were characterized by UV, XRD, SEM, TEM and EDS studies. The UV-Vis spectrophotometer results were promising and showed a rapid production of TiO(2) NPs with a surface plasmon resonance occurring at 284 nm. The formation of the TiO(2) NPs as observed from the XRD spectrum is confirmed to be TiO(2) particles in the rutile form as evidenced by the peaks at 2θ=27.42°, 36.10°, 41.30° and 54.33° when compared with the literature. The TEM images showed polydisperse nanoparticles with spherical shapes and size 23±2 nm ranges.

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

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. Moreover, we have identified Montmorillonite KSF clay as a catalyst to obtain regiospecific expected dihydrobenzo[1,7]phenanthroline-3-carbonitrile product and NaH for the regiospecific formation of unexpected Michael addition 5,6-dihydrobenzo[1,7]phenanthroline products. On the basis of a systematic study, the novel regiospecificity could be assigned by the utilization of a suitable catalyst.

Synthesis, spectral characterization and larvicidal activity of acridin-1(2H)-one analogues

Acridin-1(2H)-one analogue of 7-chloro-3,4-dihydro-9-phenyl-2-[(pyridine-2yl) methylene] acridin-1(2H)-one, 5 was prepared by using 7-chloro-3,4-dihydro-9-phenylacridin-1(2H)-one, 3 and picolinaldehyde, 4 in the presence of KOH at room temperature. These compounds were characterized by analytical and spectral analyses. The purpose of the present study was to assess the efficacy of larvicidal and repellent activity of synthesized 7-chloro-3,4-dihydro-9-phenyl-acridin-1(2H)-one analogues such as compounds 3 and 5 against the early fourth instar larvae of filariasis vector, Culex quinquefasciatus and Japanese encephalitis vector, Culex gelidus (Diptera: Culicidae). The compound exhibited high larvicidal effects at 50mg/L against both the mosquitoes with LC(50) values of 25.02 mg/L (r(2)=0.998) and 26.40 mg/L (r(2)=0.988) against C. quinquefasciatus and C. gelidus, respectively. The 7-chloro-3,4-dihydro-9-phenyl-acridin-1(2H)-one analogues that are reported for the first time to our best of knowledge can be better explored for the control of mosquito population. This is an ideal ecofriendly approach for the control of Japanese encephalitis vectors, C. quinquefasciatus and C. gelidus.

Solvatochromic behaviour and larvicidal activity of acridine-3-carboxylates

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, (1)H NMR, (13)C 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 LC50 values revels that, the synthetic compounds are non toxic.

In Vitro Larvicidal and Antioxidant Activity of Dihydrophenanthroline-3-carbonitriles

Many naturally occurring and synthetic compounds containing dihydrocyanopyridine and cyanopyran moiety show pharmacological properties. The aim of this study is to investigate the larvicidal and antioxidant potential of dihydrophenanthroline-3-carbonitrile derivatives 4a–f. A novel series of 2-amino-10-chloro-4,12-diphenyl-1,4,5,6-tetrahydrobenzo[j][1,7]phenanthroline-3-carbonitrile derivatives were synthesized by reacting different substituted acridine chalcones through Michel addition. The compounds were synthesized in excellent yields and the structures were corroborated on the basis of FT-IR, 1H NMR, 13C NMR, and ESI Mass analysis data. All the synthesized compounds were evaluated for larvicidal activity against Aedes aegypti and Culex quinquefasciatus larvae. Furthermore, the antioxidant activity was studied by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay method. From the antioxidant assay, the compound 4c was reported with profound antioxidant potential.

In Silico Molecular Docking and In Vitro Antidiabetic Studies of Dihydropyrimido[4,5-a]acridin-2-amines

An in vitro antidiabetic activity on α-amylase and α–glucosidase activity of novel 10-chloro-4-(2-chlorophenyl)-12-phenyl-5,6-dihydropyrimido[4,5-a]acridin-2-amines (3a–3f) were evaluated. Structures of the synthesized molecules were studied by FT-IR, 1H NMR, 13C NMR, EI-MS, and single crystal X-ray structural analysis data. An in silico molecular docking was performed on synthesized molecules (3a–3f). Overall studies indicate that compound 3e is a promising compound leading to the development of selective inhibition of α-amylase and α-glucosidase.

Synthesis and insecticidal activity of acridone derivatives to Aedes aegypti and Culex quinquefasciatus larvae and non-target aquatic species

A serious Mosquito borne yellow fever is one of the grave diseases which affect the major population. Since there is no specific treatment for yellow fever, there is a necessity to develop an effective agent. The series of acridinone analogues 3 to 5 were synthesized with help of non-conventional microwave heating and confirmed by respective spectral characterization. 5c and 3b showed highest activity to kill 90% of larvae against A. aegypti and C. quinquefasciatus, respectively. Also the active products were treated to check the mortality of non-target aquatic species. Through the reports of the larvicidal bioassay, compounds 3b against C. quinquefasciatus whereas 5c against A. aegypti were found to be more active. By keeping this as a platform, further extension of the work can be done to find out a valuable drug for controlling disease vectors.

An Efficient and Novel technique to Cluster the User Interests in E-commerce with Web Usage Mining for Web Personalization

It is a typical perspective that users scanning practices mirror their actual enthusiasm for items at an E-commerce site. With the advancement of E-commerce, users persistent exploring also, buying practices can be totally put away. Clickstream information are records of users searching practices, which give data about the way the users and their log time on every page. Typically, customized administrations can be offered based on this data by E-business administration suppliers. To encourage changing and customized ware suggestions, inside classification as well as cross category, an interest arranged technique taking into account clickstream information mining is proposed in this paper to group clients with clusters. Another meaning of users advantage is presented surprisingly as a set of the inclination for product classifications. Keeping in mind the end goal to portray online users practices and mirror their advantage, three primary pointers visiting path, browsing frequency and relative length of access time are taken into consideration clickstream information. As per these pointers, a moved forward grouping calculation with unpleasant set hypothesis is utilized to clusterusers with comparable interest is done using Frequency-Inverse Document Frequency (TF-IDF). The test result demonstrates that this calculation is successful and appropriate. The consequence of this proposed calculation can be connected to strengthen basic leadership for E-commerce locales. Our proposed methodology is prepared to do clustering of web users from web log information.