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Recently, heterocyclic compounds play important role in drug industries. The benzothiazole (BTA) is a bicyclic compound in heterocyclic because of their biological properties. In this paper the synthesis and characterization of benzothiazole were reported. The chemical structures of synthesized compounds were established based on spectral data of 1HNMR, 13CNMR, and IR. The mass of the novel compounds was established with the help of the LCMS test. The formation of the crystal was confirmed by powder XRD and the sharp peaks show the purity and crystalline nature of the samples. The photoluminescence spectra explain the optical property of the compound. The biological studies of synthesized compounds show that compound 5c possesses good antibacterial activity and compound 5d has good antifungal activity.

Objective: The objective of this work is to synthesis thio-1,3,4-oxadiazol-2-yl derivatives for industrial applications. Methods: The synthesis was done by the reaction of (S)-2-amino-2-phenylacetic acid with ethanol-derived ethyl (S)-2-amino-2-phenylacetate. The reaction of ethyl (S)-2-amino-2-phenylacetate with Boc anhydride and hydrazine produces ethyl (S)-2-((tert-butoxycarbonyl)amino)-2-phenylacetate. The intermediate 5-alkyl amino-1,3,4-oxadiazole-2-thiols have been isolated as stable compounds. Results: To study the characteristics of these compounds, they are subjected to 1HNMR, 13CNMR, and IR. These studies examine the chemical structure of synthesized compounds. The mass of the novel compounds was established with the help of the LCMS test. The structural and optical properties were examined by the powder XRD and photoluminescence spectrum respectively. Conclusion: The sharp intense peak in the powder XRD indicates the crystal nature of the sample. The values obtained from the LCMS test indicate that the compounds have good thermal stability. The absorption peak at 358 nm in the PL spectrum indicates that the sample can be used in photoelectronic devices.

Novel quinazoline derivatives were synthesized by reacting isatoic anhydride and 4-amino acetanilide to synthesize N-(4-(2,4-dioxo-1,2- dihydroquinazolin-3(4H)-yl)phenyl)acetamide which in turn reacted with substituted aromatic aldehydes to synthesize novel chalcones. The chalcones were allowed to react with hydrazine hydrochloride and guanidine to form pyrazoline and pyrimidine derivatives, respectively. The newly synthesized compounds were characterized by IR, NMR (1H, 13C), mass and elemental analysis. All the newly synthesized derivatives were screened for in vitro antimicrobial and antioxidant activities to evaluate their biological potency.

In present work, ethyl 2-aminobenzo[d]thiazole-6-carboxylate was reacted to piperidine using copper(II) bromide to get ethyl 2-(piperidin-1-yl)benzo[d]thiazole-6-carboxylate. The reaction of ethyl 2-(piperidin- 1-yl)benzo[d]thiazole-6-carboxylate with NaOH produces 2-(piperidin-1-yl)benzo[d]thiazole-6- carboxylic acid. The inter-mediate 2-(piperidin-1-yl)benzo[d]thiazole-6-carboxylic acid have been isolated as stable compounds. The chemical structures of synthesized compounds were established based on the 1H & 13C NMR and IR spectral data. The mass of the novel compounds was established with the help of the LC-MS technique. The photoluminescence spectra explain the optical property of the compound. The biological studies of synthesized compounds show that the compound 5e possesses good antibacterial activity and compound 5d has good antifungal activity.

Mosquito borne diseases are on the rise because of their fast spread worldwide and the lack of effective treatments. Here we are focusing on the development of a novel anti-malarial and virucidal agent with biocidal effects also on its vectors. We have synthesized a new quinoline (4,7-dichloroquinoline) derivative which showed significant larvicidal and pupicidal properties against a malarial and a dengue vector and a lethal toxicity ranging from 4.408 µM/mL (first instar larvae) to 7.958 µM/mL (pupal populations) for Anopheles stephensi and 5.016 µM/mL (larva 1) to 10.669 µM/mL (pupae) for Aedes aegypti. In-vitro antiplasmodial efficacy of 4,7-dichloroquinoline revealed a significant growth inhibition of both sensitive strains of Plasmodium falciparum with IC50 values of 6.7 nM (CQ-s) and 8.5 nM (CQ-r). Chloroquine IC50 values, as control, were 23 nM (CQ-s), and 27.5 nM (CQ-r). In vivo antiplasmodial studies with P. falciparum infected mice showed an effect of 4,7-dichloroquinoline compared to chloroquine. The quinoline compound showed significant activity against the viral pathogen serotype 2 (DENV-2). In vitro conditions and the purified quinoline exhibited insignificant toxicity on the host system up to 100 µM/mL. Overall, 4,7-dichloroquinoline could provide a good anti-vectorial and anti-malarial agent.

A novel series of thiophene and benzodioxole appended thiazolyl-pyrazoline derivatives have been designed, synthesized and evaluated against different bacteria and fungi. The antimicrobial activity of the synthesized compounds were screened using MIC method and were proved synthesized compounds 7o , 7r and 7t to show good antimicrobial activity against bacteria and fungi. In silico molecular docking studies revealed that all the synthesized molecules showed good binding energy toward the target receptor DNA topoisomerase IV, ranging from −10.42 to −11.66 kcal/mol.

The kinetics of benzimidazolium fluorochromate (BIFC) catalysed oxidation of indole-2aldehyde (2-InA) with perchloric acid in 50% acetic acid–50% water solvent mixture at 303 K has been followed spectrophotometrically. The reaction is first order with respect to [BIFC], [2-InA] and [H + ] and the reaction is catalyzed by hydrogen ions. A suitable mechanism has been proposed.

A vast array of thiazole derivatives having excellent broad spectrum activity forms an invaluable part of the present armory of the clinicians. A novel series of th iazole compounds were synthesized and screened for the anti - bacterial and anti - fungal activity. The structures of these compounds were ascertained by IR H 1 NMR, mass spectra and elemental analysis. The anti - bacterial activity of the synthesized compounds w ere evaluated against gram positive bacte ria and gram negative bacteria all the compounds had shown moderate to sign ificant anti - bacterial activity . The anti - fungal activity of the compounds is more significant than anti - bacterial activity.

Removal of potassium is carried out by lime loaded rice husk carbon (LRHC). The extent of removal depends on initial concentration of potassium in solution, pH of the solution, carbon dosage, temperature etc. As the concentration of potassium is increased, the removal of potassium is decreased. When the adsorbent dosage is increased from 1 g to 4 g, the removal of potassium from the salt solution is increased. As the pH increased from 3 to 6, the removal of potassium had been decreased. The amount of potassium removed increases from pH 6 to 7. Freundlich and Langmuir adsorption isotherm models indicate the occurrence of adsorption. Thermodynamic parameters show the biosorption is endothermic and non-spontaneous. Kinetics shows the adsorption is first order reaction. IR spectrum indicates the adsorption is physisorption. SEM and EDX studies show the adsorption of potassium on the carbon.

Novel 3,4,5-triarylisoxazole derivatives were synthesised by Suzuki reaction of 4-bromo-3, 5-diaryl isoxazoles with various boronic acid under microwave condition. The structures of the newly synthesised compounds are characterised by 1 H NMR, 13 C NMR, LC-MS and screened for their antifungal activity against Aspergillus flavus (NCIM No. 524), Fusarium oxysporum (NCIM No. 1072) and Candida albicans (NCIM No. 3102).

Department of Chemistry, C. Abdul Hakeem College (Autonomous), Melvisharam-632 509, Tamilnadu, India E-mail : smansoors2000@yahoo.co.in Department of Chemistry, Periyar Government Arts College, Cuddalore-607 001, Tamilnadu, India Department of Chemistry, Thiruvalluvar University, Serkadu, Vellore-632 106, Tamilnadu, India Manuscript received online 19 November 2014, accepted 11 June 2016 The oxidation of some heterocyclic aldehydes (HA) like 2-furaldehyde, 2-pyrrole-carbaldehyde and 2-thiophene­carbaldehyde by benzimidazolium fluorochromate (BIFC) have been studied in aqueous acetic acid medium. The oxidation leads to the formation of the corresponding carboxylic acids. The reaction is first order with respect to BIFC, heterocyclic aldehydes and [H+] and the reaction is catalyzed by hydrogen ions. The reaction has been studied in different percentage of acetic acid-water mixture. A suitable mechanism has been proposed.

Department of Chemistry, C. Abdul Hakeem College (Autonomous), Melvisharam-632 509, Tamilnadu, India E-mail : smansoors2000@yahoo.co.in Department of Chemistry, Periyar Government Arts College, Cuddalore-607 001, Tamilnadu, India Department of Chemistry, Thiruvalluvar University, Serkadu, Vellore-632 106, Tamilnadu, India Manuscript received online 23 October 2014, accepted 11 June 2016 Kinetics of oxidation of 4-oxo-4-phenyl butanoic acid (4-oxo acid) by benzimidazolium fluorochromate (BIFC) in acetic acid-water medium in the presence of perchloric acid has been studied. The reaction is first order each in [BIFC], [4-oxo acid] and [H+]. The reaction has been found to be catalyzed by H+ ions. The stoichiometry of the reaction is 1 : 1 and the product of oxidation is benzoic acid. The reaction rate increased remarkably with the increase in the proportion of acetic acid in the solvent medium. The reaction rates have been determined at different temperatures and the activation parameters were calculated. The reaction failed to induce the polymerization of acrylonitrile, i.e. absence of free radicals. From the observed kinetic results a suitable mechanism has been proposed.

Tetraethylammonium bromochromate (TEABC) oxidation of 18 meta- and para-substituted benzyl alcohols (BnOH) in dimethylsulphoxide (DMSO) leads to the formation of corresponding aldehydes. The reaction is first order each in TEABC and the alcohols. The reaction is catalyzed by hydrogen ions. The hydrogen ion dependence has the form: k obs=a+b[H+]. The oxidation of αα ´-dideuterio benzyl alcohol exhibited a substantial primary kinetic isotope effect (k H/k D=5.71 at 303 K). Oxidation of benzyl alcohol was studied in 17 different organic solvents. The solvent effect has been analyzed using Kamlet's and Swain's multi parametric equation. A correlation of data with Kamlet–Taft solvatochromic parameters (α, β, π *) suggests that the specific solute-solvent interactions play a major role in governing the reactivity. A mechanism involving a hydride ion transfer via chromate ester is proposed.

Polyaniline clay nanocomposite can be prepared by mechano-chemical method in which intercalation of anilinium ion into the clay lattices accomplished by mechanical grinding of sodium montmorillonite (Na+MMT) in presence of anilinium hydrochloride at room temperature using mortar & pestle for about 30 min and subsequent grinding with oxidizing agent, ammonium peroxysulfate. The appearance of green colour indicates the formation of polyaniline/clay nanocomposite (PANI/Clay). Similarly aniline derivatives likeo-toludine ando-anisidine in the form of HCl salt can form intercalation into the clay lattices. The intercalated aniline derivatives were ground mechanically in presence of oxidizing agent ammonium peroxysulfate lead to formation of substituted polyaniline/ clay nanocomposites. The characteristics of various polyaniline-clay nanocomposites were investigated using UV-Visible, FT-IR, cyclic voltammetry studies.

1,5-Disubstituted 1,2,3-triazoles are formed through a novel domino reaction involving the addition of aromatic azides to an excess of allenylmagnesium bromide with concomitant N-C heterocyclization followed by the addition of another mole of allenylmagnesium species to generate the terminal acetylenic product in moderate to high yields.

With exception of bulky substrate (IIIb), aromatic β-ketoesters are selectively converted into the corresponding β-hydroxy ketones following the sequence A) and B).

The kinetics of oxidation of benzhydrols (BH) by tributylammonium chlorochromate (TriBACC) to the corresponding benzophenones have been studied. The reaction is first order each in the concentration of TriBACC, benzhydrol and H+. The oxidation of (α-C–D) benzhydrol indicates the presence of a primary kinetic isotope effect. The reaction rate have been determined at different temperatures and activation parameters calculated. With an increase in the amount of acetic acid in its aqueous mixture, the rate increases. The reaction does not induce polymerization of acrylonitrile. A mechanism involving hydride ion transfer has been proposed.

5-Butynylisoxazoles were obtained in high yields through a domino addition, C–O heterocyclization involving allenylmagnesium bromide and benzonitrile oxide in dry THF, in which the corresponding 5-methylisoxazoles were isolated in trace amounts. However, when the reactions were attempted in aqueous media using allenylindium bromide, 5-methylisoxazoles were formed as the sole products in high yields.

The kinetics of oxidation of some organic diols by tripropylammonium fluorochromate (TriPAFC) have been studied in dimethylsulfoxide (DMSO). The main product of oxidation is the corresponding hydroxy aldehydes. The reaction is first order with respect to TriPAFC and exhibited Michaelis-Menten type kinetics with respect to organic diols. The reaction is catalyzed by hydrogen ions. The hydrogen ion dependence has the form: k obs = a + b [H + ]. Various thermodynamic parameters for the oxidation have been reported and discussed along with the validity of isokinetic relationship. Oxidation of diols was studied in 18 different organic solvents. The rate data are showing satisfactory correlation with Kamlet–Taft solvotochromic parameters ( α , β and π ∗ ). A suitable mechanism of oxidation has been proposed.

The kinetics of oxidation of methionine (Met) by benzimidazolium fluorochromate (BIFC) has been studied in the presence of chloroacetic acid. The reaction is first order with respect to methionine, BIFC and acid. The reaction rate has been determined at different temperatures and activation parameters calculated. With an increase in the mole fraction of acetic acid in its aqueous mixture, the rate increases. The solvent effect has been analyzed using the Kamlet’s multi parametric equation. A correlation of data with the Kamlet–Taft solvatochromic parameters (α, β, π∗) suggests that the specific solute–solvent interactions play a major role in governing the reactivity. The reaction does not induce polymerization of acrylonitrile. A suitable mechanism has been proposed.