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Synthesis and characterization of novel quinoxaline-1,2,3-triazole hybrid heterocyclic derivatives have been carried out, and their antimicrobial activity has been tested. Antibacterial and antifungal studies of the synthesized compounds have demonstrated high to moderate activity against the tested pathogens for most of those. Several products have been determined to be potent antimicrobial agents at concentrations of 75 and 100 µg/mL as compared to the standard drug Gentamicin.

Synthesis of a novel series of chalcone based 1,2,3-triazole derivatives and their anti-cancer studies are presented. Majority of the target compounds exhibit moderate to excellent activity against A-549 cells. Among the compounds screened 7c and 7j demonstrate potent activity being compared with the standard drug Doxorubicin.

A PEG-mediated green synthesis of 6-pyrazinyl-/fused pyrazinylquinazolin- 4(3H)-ones was developed starting from 6-iodo-3-methyl-2-phenylquinazolin- 4(3H)-one by means of quinazolinone-based internal alkyne/1,2-diketone as intermediates using the Castro?Stephen coupling reaction/potassium permanganate mediated oxidation and cyclocondensation reactions.

A series of bis-1,2,3-triazole based chalcones has been synthesized in high yields. The newly synthesized compounds are characterized by IR, NMR and mass spectroscopy. The combination of the pharmacologically active moieties in a single scaffold results in their synergistic effect and high antimicrobial activity against several bacterial and fungal strains. The compounds 4f, 4l, 4e, 4k, 4c, and 4i demonstrate potent antimicrobial activity at concentrations of 75 and 100 µg/mL.

This paper reports to the fluoride and nitrate concentration in groundwater resources of the semi-arid region of Anantapur district, South India, and its related potential health risk assessment issues with the resident peoples. For this purpose, 50 groundwater samples were analyzed for hydrochemical parameters including major ions, fluoride and nitrate. The results revealed that most of the groundwater samples are alkaline in nature. Hydrochemical type of groundwater in the study area mainly Na+-K+-Cl−-SO42− and few samples belong to Na+-K+-HCO3−. Non carcinogenic health risks due to fluoride and nitrate exposure through consumption of groundwater were assessed using the USEPA method. In the study area groundwater samples, fluoride and nitrate concentration ranges from 1.2 to 5.9 mg/L and 36 to 92 mg/L. Based on these results, 86% of fluoride (>1.5 mg/L) and 94% of the nitrate (>45 mg/L) in groundwater samples exceed the permissible limit. The Total Hazard Index (THI) quotients for adults, children and infants had health hazards (THI > 1) in 98%, 88%, and 80% of samples, respectively. Hence, proper precautionary measures have to be taken to control health risk in this area.

A series of novel benzofuran-isoxazole 7a–7j hybrid heterocyclic molecules are synthesized. The structures of compounds 7a–7j are assessed by IR, NMR, MASS spectroscopy and elemental analysis. The target compounds 7a–7j are screened for their antibacterial activity and demonstrated excellent to moderate activity against gram-positive and gram-negative bacteria.

The main objective of the present study was to determine the distribution levels of nitrate contamination in groundwater and its associated impact on human health risk in the Yerraguntla mandal, South India. For this 40 ground water samples were collected randomly during April 2018. Nitrate concentration in groundwater samples ranged from 2.50 to 760.12 mg/L, with a mean value of 86.13 mg/L. Most of the groundwater samples are exceeding the permissible limits of nitrate (45 mg/l). Hence health risk assessment of nitrate has been carried out. Hazard quotient (HQ) values for infants, children, male and female ranges from 0.05 to 14.25; 0.06 to 18.53; 0.04 to 12.18 and 0.05 to 14.62, respectively. The finding of data showed that HQ value was more than 1 in 42.5% of samples in groups of infants, children and female, and 35% of samples in group of male.

A series of novel benzofuran-1,2,3-triazole hybrid molecules are synthesized using the click chemistry approach. Structures of the synthesized compounds were assessed by IR, NMR, and mass spectroscopy. The tests of final products 10a–10l for their antibacterial activity demonstrate excellent to good activity against gram-positive and gram-negative bacteria.

A series of novel 9-{2-[(1H-1,2,3-triazol-4-yl)methoxy]phenyl}-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione derivatives were synthesized by a click chemistry approach. The structures of all the newly synthesized compounds were characterized by IR, MASS, 1H and 13C NMR spectral data. The final analogues showed good to excellent antibacterial and antifungal activities in an agar well diffusion assay. Compounds 6i and 6f were the most active against all the test bacterial and fungal strains.

In the present study, a series of novel {6-[(1H-1,2,3-triazol-4-yl)methoxy]-3-methylbenzofuran-2-yl}(phenyl)methanones (7a–7o) have been synthesized using click chemistry approach. The structures of all newly synthesized compounds were characterized by FT-IR, 1H and 13C NMR, and MASS spectral data. Most of products demonstrated high antimicrobial activity.

Groundwater is a vital resource for most developmental activities. Demand for groundwater is increasing due to paucity of surface water and recurrent failures of monsoons. Increasing demand for groundwater causes water level to decline and water quality to deteriorate. This data article is aimed to investigate the quality of drinking water of Obulavaripalli Mandal YSR district based on water quality Index (WQI). To evaluate WQI in the study area, twenty groundwater samples were collected and different physico-chemical parameters viz., pH, EC, TDS, TH, total alkalinity (TA), calcium (Ca2+), magnesium (Mg2+), chloride (Cl−), sulphate (SO42−) and fluoride (Fˉ) were analyzed. WQI data for groundwater samples indicated that 30% of the samples fall under excellent rating, 40% of the samples fall under good category and another 30% of the groundwater is under poor category. Overall groundwater quality is not suitable for drinking purpose. Keywords: Water quality index, Water quality assessment, Obulavaripalli, Y.S.R district

Insecticidal resistance studies against third instar larvae of DBM (Plutella xylostella L.) were carried out to know the rate of development of resistance from F1 to F3 generations in Karnataka population. The third instar larvae obtained from field were subjected to bioassay studies with tested against acephate, cypermethrin, spinosad, cartap hydrochloride and Cry2Ab toxin using leaf dip method to calculate LC50 values. The LC50 values of the insecticides were further used to quantify the resistance in P. xylostella of parental generation (F0) from Karnataka field population. The survivals from F0 generation were reared to next generation (F1). Resistance development studies was assessed from F1 to F3 generation with third instar larvae in every generation with a concentration that caused 80.00 % mortality for all the test insecticides and Cry2Ab toxin. Results revealed that ((0.17 folds) no resistance was developed against acephate in F3 generation. In case of cypermethrin 2.33 folds. Resistance studies further revealed that 1.50 folds resistance was developed against spinosad, 2.28 folds against cartap hydrochloride and Cry2Ab toxin 1.49 folds resistance was recorded in F3 generation. The rate of development of resistance from F1 to F3 generations increased in all the test insecticides and Cry toxin, except against acephate in Karnataka population. This data will be useful in the development of insecticide resistance management approach for DBM.

In the present study, a novel series of 1,2,3-triazole derivatives have been synthesized using click chemistry approach. The structures were confirmed by spectroscopic methods. The products were screened for their in vivo anti-inflammatory activity. The tested compounds 6a, 6f, 6g, 6i, 6j, 6n, and 6p, demonstrated potent anti-inflammatory activity compared to the reference drug ibuprofen. Molecular docking studies of these 1,2,3-triazole derivatives into the active site of human cyclooxygenase-2 (COX-2) (PDB code 4PH9) demonstrated good affinity for the enzyme and suggested binding properties similar to ibuprofen.

The main focus of this study is to evaluate the groundwater quality through drinking water quality index and regression analysis in semi-arid region and the results are examined with reference to the drinking water quality standards laid down by WHO. Water quality index (WQI) was determined from fourteen physicochemical parameters like pH, EC, TDS, total hardness, total alkalinity, sodium, potassium, calcium, magnesium, chloride, bromide, nitrate, sulphate and fluoride. The drinking water quality index values range from 32.8 - 442.4, indicating three categories i.e. poor, very poor and unfit, which are inappropriate for drinking. Regarding correlation analysis results, EC, TDS, TH, Na+, Mg2+, Ca2+ and Cl− shows high correlation. Most of the parameters are more or less correlated with each other, regression relations have the same correlation coefficients and pH, Na+, EC, TDS, Mg2+, Ca2+, Cl−, SO42−, CO32−, TH were significantly positively correlated (R>0.9), indicate the increase in the pollution load.

The present paper aims at determining the status and trends of groundwater quality by applying water quality index method from 22 villages around Cement industries, Yerraguntla Mandal, Y.S.R District, A. P South India. Water Quality Index (WQI) was calculated from fourteen physicochemical parameters like pH, EC, TDS, Total hardness, Total alkalinity, Sodium, potassium, Calcium, Magnesium, chloride, Bromide, nitrate, sulphate and fluoride. The computed WQI values range from 123 to 1121 and water quality varies from poor water to water unsuitable for drinking. Most of the groundwater from this place is not suitable for drinking.

Genetic diversity in acephate, spinosad and Cry2Ab resistant Plutella xylostella collected from three states of India was assessed by RAPD markers. The DNA extracted from larvae was subjected to polymerase chain reaction using 10 RAPD primers. The highest number alleles (7) were produced by primer ABA-13, followed by six alleles each by primers ABA-2, 7, 8, 11, 14; five alleles each were produced by ABA-4, 9, 10, 12. UPGMA analysis clustered the acephate, spinosad and Cry2Ab treated P.xylostella populations into two groups with overall similarity level of 33%, 27% and 34% respectively. Cluster A consisted 11 samples while Cluster B consisted only F1 of acephate and spinosad treated Karnataka population. In Cry2Ab treated population Cluster B comprised 11 samples and Cluster A had out grouped singly i.e. F0 generation from Karnataka. The genetic variability between the acephate, spinosad and Cry2Ab treated populations ranged from 33 to 69%, 27 to 56% and 34 to 69% respectively. Acephate and spinosad treated F1 population and Cry2Ab treated F0 population from Karnataka were out grouped from rest of the populations.

This study reports the evaluation of groundwater suitability for domestic and agricultural utility in semi-arid region of Anantapur, Andhra Pradesh State, South India. Fifty groundwater samples were analysed for parameters such as pH, electrical conductivity, total dissolved solids, total alkalinity, total hardness, bicarbonates, calcium, magnesium, nitrate, sulphate , phosphate, sodium, potassium and fluoride. The analysis results shows that the concentration of fluoride in 42 samples out of 50 exceed the limit for fluoride (1.5 mg/L) in drinking water set by the W.H.O. Based on the WQI shows overall quality of groundwater is not suitable for drinking purpose. It is inferred from the study that these water sources can be used for potable purpose only after prior treatment. The parameters such as sodium adsorption ratio, per cent sodium, residual sodium carbonate, were calculated for the evaluation of irrigation water quality. Groundwater chemistry was also analysed by statistical analysis, USSL, Wilcox and Piper diagrams, to find out their suitability for irrigation and the analysis reveals that most of groundwater samples of the study area fall under excellent class suitable for irrigation.

Groundwater forms the major source of drinking water in the rural areas of most of the developing nations in the world. Presence of high concentration of fluoride and nitrate in groundwater is a major problem in many countries as it causes health related problems. The present study was carried out with the objective of determining the causes for higher fluoride and nitrate concentration in groundwater in parts of Anantapur District, Andhra Pradesh, India. Fluoride and nitrate concentration in groundwater of this area was analysed by collecting groundwater samples from forty-four representative dug wells. Samples were collected during March 2009-January 2010. The concentration of fluoride in the water samples ranged between 0.1 mg/l and 7.0 mg/l 76% of the water samples contain fluoride above the maximum permissible limit. Possible sources of fluoride in groundwater are weathering and leaching of fluoride bearing minerals from the basement granitic rocks of this region under alkaline environment. By nature, the granitic rocks of this area possess fluoride values greater than the world average content in granitic rocks. The highest concentration of nitrate recorded during the sampling period was 110 mg/l and the lowest concentration was below detection limit. Taking into consideration 45mg/l of nitrate as the maximum permissible limit for drinking water set by BIS, it was found that 12% of the groundwater samples collected from this study area possessed nitrate concentration beyond the limit. Overall, dug wells present in agricultural fields had nitrate levels within permissible limits when compared to those groundwater samples from dug wells present in settlements which were used for domestic purpose. This indicates that the high nitrate concentration in groundwater of this area is due to leaching from indiscriminate dumping of animal waste. Anthropogenic activities like application of fertilizers for agriculture contribute only little to the groundwater dug well as fluoride. The major contribution of the paper is that the dug wells in the Kadiri, Mudigubba and Nallamada Mandals of Anantapur District, Andhra Pradesh have been demarcated into safe and unsafe dug wells for consumption of water with respect to fluoride. Keywords-Groundwater; Fluoride; Nitrate; Anthropogenic; Anantapur District; India

D-Glycals undergo smoothly allylic rearrangement with allyltrimethylsilane and trimethylsilyl cyanide in the presence of catalytic amount of bismuth triflate to afford the corresponding 2,3-unsaturated allyl glycosides and glycosyl cyanides in excellent yields with high α-selectivity.

Aryl imines formed in situ from aryl aldehydes and aromatic amines undergo smooth [4+2] cycloaddition reactions with cyclic enol ethers such as 3,4-dihydro-2H-pyran and 2,3-dihydrofuran in the presence of 10 mol % SelectfluorTM in acetonitrile at room temperature to afford pyrano- and furanotetrahydroquinoline derivatives in excellent yields with high endo-selectivity.

The occurrence of fluoride (F−) concentration in groundwater is mainly due to natural or geogenic pollution and the source of contamination is often unknown (Handa 1975a; Saxena and Ahmed 2002). Geogenic contamination of groundwater depends mainly on the geological setting of an area. As rain water infiltrates through soil and reaches the water table, it can dissolve partly certain component of bedrock. The F− content of groundwater can thus originate from the dissolution of fluorine-bearing minerals in the bed rock. In other words, bed rock mineralogy is a primary factor in general for the variations in F− content of groundwater (Chae et al. 2007; Raju et al. 2012). F− contamination of groundwater is a function of many factors such as availability and solubility of fluorine-bearing minerals, temperature, pH, concentration of calcium and bicarbonate ions in water, etc. (Chandra et al. 1981; Largent 1961). In contrast to anthropogenic pollution of surface water, geogenic contamination of groundwater is difficult to detect and even more difficult to control. The presence of excessive concentrations of F− in groundwater may persist for years, decades or even centuries and can reach the food system (Todd 1980). In recent years, there has been an increased interest in F− research because high concentration of F− in groundwater causes adverse impact on human health. In order to mitigate the excessive F− in groundwater, it is essential to determine and monitor the casual factors of enrichment of F− concentration in groundwater in time and space (Ahmed et al. 2002; Raju et al. 2009).

Fresh samples of Xanthosoma sagitifolium were pretreated with sodium hexametaphosphate (SHMP), potassium metabisulphite (KMS), sodium chloride (NaCl) and aqueous ammonia, all in a concentration range of 1-5 % (w/v), and with glyceryl monostearate (GMS) at 0.025–0.125 % concentrations. The properties of these pretreated samples were compared with those of the control obtained by direct water extraction. The properties of the starch pretreated with chemicals showed characteristic changes regarding amylose contents, especially soluble amylose, and lipid extractability. Starch samples prepared from fresh roots pretreated with sodium chloride displayed a lower amylase digestibility. Control starch samples and the one prepared from roots pretreated with 5 % aqueous ammonia showed the highest amylase activity at 20 min incubation time. Other experimental samples showed only marginal changes.

A new method for the stereoselective synthesis of trans-2,6-disubstituted 3,6-dihydro-2H-pyrans with a variety of substitution patterns is described, involving Lewis acid induced tandem allylation or cyanation of δ-hydroxy-α,β-unsaturated aldehydes to produce dihydropyrans in good yields and with trans-selectivity. This method is very useful for the synthesis of trans-2,6-disubstituted dihydropyran ring-containing natural products such as laulimalide, scytophycin C and many others.

Fresh roots of Amorphophallus paeoniifolius were separately pretreated with sodium hexametaphosphate (SHMP), potassium metabisulphite (KMS), sodium chloride (NaCl), and ammonium hydroxide (NH4OH) within a range of 1–5% (w/v) concentration and glyceryl monostearate (GMS) at 0.025–0.125% concentration. The quality of starch extracted from pretreated roots was compared with that obtained from fresh roots by direct aqueous extraction. The starch samples prepared from chemically pretreated roots showed characteristic changes in properties of water soluble amylose content, swelling and solubility and α-amylase susceptibility. X-ray diffraction of starch samples from chemically pretreated roots although resembled that of control, there was noticeable shift with respect to their ‘d’ spacing and Io/Imax values.

A new method for the stereoselective synthesis of trans-2,6-disubstituted 3,6-dihydro-2H-pyrans with a variety of substitution patterns is described, involving Lewis acid induced tandem allylation or cyanation of δ-hydroxy-α,β-unsaturated aldehydes to produce dihydropyrans in good yields and with trans-selectivity. This method is very useful for the synthesis of trans-2,6-disubstituted dihydropyran ring-containing natural products such as laulimalide, scytophycin C and many others.

D-Glycals undergo smoothly allylic rearrangement with allyltrimethylsilane and trimethylsilyl cyanide in the presence of catalytic amount of bismuth triflate to afford the corresponding 2,3-unsaturated allyl glycosides and glycosyl cyanides in excellent yields with high α-selectivity.

Aryl amines react with endocyclic ene-carbamates such as tert-butyl 2,3-dihydro-1H-1-pyrrolecarboxylate and tert-butyl 1,2,3,4-tetrahydro-1-pyridinecarboxylate, on the surface of montmorillonite KSF clay under mild conditions to afford the corresponding 3-aminopropylhexahydropyrrolo[3,2-c]quinoline or 4-aminobutyloctahydrobenzo[h][1,6]naphthyridine derivatives in excellent yields with moderate diastereoselectivity.

Field populations of DBM sampled from Andhra Pradesh, Karnataka and Delhi were used in bioassays with insecticides acephate, cypermethrin, spinosad, cartap hydrochloride and Cry2Ab toxin over a period of three generations (F1-F3) to obtain respective insecticide resistant strains. The individual insecticide resistant strains were used to estimate the cross resistance against emamectin benzoate, chlorantraniliprole and flubendiamide. The cross-resistance ratios (CRR) obtained based on median lethal concentrations for resistant and unselected strains revealed that CRR of all the three DBM populations in acephate resistant strain (AR) ranged from 0.52–0.82, 0.31–0.64 and 0.37–0.75; cypermethrin resistant strain (CyR) ranged from 0.41–0.76, 0.29–0.80 and 0.37–1.12; spinosad resistant strain (SR) ranged from 0.35–0.64, 0.29–0.65 and 0.37–0.62 cartap hydrochloride resistant strain (ChR) ranged from 0.58–0.88, 0.45–0.50 and 0.50–0.87. Cry2Ab resistant strain (CryR) ranged from 0.29–0.82, 0.33–0.69 and 0.62–0.75 respectively. Except for cypermethrin resistant strain of DBM from Delhi that showed cross resistance to flubendiamide no other DBM insecticide resistant strains exhibited cross resistance to emmamectin benzoate, chlorantraniliprole and flubendiamide.