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Cation recognition plays a vital role in defining advanced functions of macromolecules in nature. An example of such an interaction is the action of a natural antibiotic, valinomycin, that behaves as a potassium ionophore. It encages the cation to transport it across a cell membrane and easily releases it inside the cell. Macrocyclic complexes of some crown ethers mimick alkali ion interactions with natural ionophores. We have synthesized complexes of two crown ethers namely benzo-15-crown-5 (2,3,5,6,8,9,11,12-octahydrobenzo[b][1,4,7,10,13]pentaoxacyclopentadecine) and dibenzo-15-crown-5 (6,7,9,10,17,18-hexahydrodibenzo[b,h][1,4,7,10,13]pentaoxacyclopentadecine with potassium halides (fluoride, chloride, bromide and iodide) in acetonitrile and characterized them by IR, UV, ESI-MS, 1H NMR and 13C NMR techniques. The effect of the anion on the stability of the complexes was observed by 1H NMR studies. The alkali metal ion is held to the oxygen donor atoms of the macrocyclic ring by ion-dipole interactions. The potential of the small ring oxacrown ethers, benzo-15-crown-5 and dibenzo-15-crown-5, to act as probes for potassium ions in dilute solutions (4.1 × 10−4 M) was investigated by recording the variation in the fluorescence spectra of benzo-15-crown-5 and dibenzo-15-crown-5 on complexation with potassium fluoride in acetonitrile and chloroform. The rigidity of the macrocyclic ring and proximity of fluorophore units affected the fluorescence intensity of the complexes.

A series of complexes of 2,3,5,6,8,9,11,12-octahydro-1,4,7,10,13-benzopentaoxacyclopentadecine (benzo-15-crown-5) with sodium halides was synthesized in acetonitrile. The effect of anion on the stability and spectral properties of complexes of benzo-15-crown-5 with sodium halides was investigated. The synthesis of complexes of sodium fluoride and sodium chloride are reported for the first time. Chloroform was used as solvent to study the assembly in solution state by 1H and 13C NMR techniques. Single crystal diffraction studies on the easily crystallizable bromide complex confirmed 1:1 stoichiometry of the complex. IR and Raman studies provided valuable evidence for a water molecule shared between the crown encapsulated cation and the counter ion to give a solvent shared ion pair (SSIP). The fluorescence spectra of the complexes were obtained in chloroform by excitation at 270nm to study the effect of complexation on the fluorescent properties of benzo-15-crown-5.

s 2-Pyrazoline derivatives (6–10) were synthesized from dibenzalacetones (1–5), formic acid and hydrazine hydrate in ethanol. The structures were elucidated by UV–Vis, FT-IR, ESI-MS, 1H NMR, 13C NMR, and microanalysis. Absorption and fluorescence spectra were recorded in methanol. Emissions occurred between 310 nm and 370 nm. Compound 6 with C-3 phenylvinyl (styryl) substituent showed remarkable red shift both in absorption and emission in comparison to compound 0 with C-3 phenyl substituent. Substitutions in compound 6 did not shift the band positions but intensity of emission increased with chloro and bromo substituents in o- and p-positions in styryl group. Compound, 10 with p-bromo substituent was found to have maximum emission intensity.

Copper complexes of 1-formyl-2-pyrazolines were prepared by the reaction of 1-formyl-2-pyrazolines with copper chloride and nitrate with methanol. The structures of copper complexes 1a–3a have been established by elemental analysis, FT-IR, UV and thermogravimetric analysis. These compounds were tested against HM1:IMSS strain of Entamoeba histolytica by the microdilution method. Complexes 2a and 3a are more active than other complexes.

Saponins are widely distributed in plant kingdom. In view of their wide range of biological activities and occurrence as complex mixtures, saponins have been purified and separated by high-performance liquid chromatography using reverse-phase columns at lower wavelength. Mostly, saponins are not detected by ultraviolet detector due to lack of chromophores. Electrospray ionization mass spectrometry, diode array detector , evaporative light scattering detection, and charged aerosols have been used for overcoming the detection problem of saponins.

The present study was carried out to determine the accumulation and variation of trace elements in roots and leaves of Asparagus racemosus collected from four different altitudes in Uttarakhand, India, by atomic absorption spectroscopy. The metals investigated were Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li. The concentration level of Fe was found to be highest at an altitude of 2,250 m, whereas the level of Cu was lowest. The maximum concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li were found to be 165.0 +/- 3.2, 34.0 +/- 0.5, 84.0 +/- 0.7, 2,040.0 +/- 0.3, 122.0 +/- 1.5, 745.0 +/- 0.3, 13,260.0 +/- 3.5, 6,153.0 +/- 1.6, and 58.0 +/- 3.8 mg/kg, respectively.

An attempt has been made to analyze some trace elements and electrolytes like Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li present in the Swertia chirayita roots and leaves. The concentration of Ca in all the samples was more than 1,346.0 mg/kg and the concentration of other elements was found in the order K > Ca > Fe > Na > Mn > Zn > Co > Cu > Li in different samples of S. chirayita.

Department of Chemistry, H. N. B. Garhwal University, Srinagar (Garhwal)-246 174, Uttarakhand, India E-mail : msmrawat@gmail.com; geeta_joshi4f54@rediffmail.com Department of Physics, H. N. B. Garhwal University, Srinagar (Garhwal)-246 174, Uttarakhand, India Manuscript received 20 December 2013, accepted 20 January 2014 The pyrazolines are well known fluorescent brightening agents and are used as chemosensors. The reaction of dibenzalacetone with hydrazine hydrate and acetic acid yielded a mixture of two products (1 and 2), purified by centrifugal chromatographic separation using chromatotron. Compound 1 was characterized as 5-phenyl-3-[(E)-2- phenylvinyl]-4,5-dihydro-1H-pyrazole-1-methylcarbaldehyde by ESI-MS, FT-IR, UV, fluorescence spectroscopy, 1H NMR data and microanalysis. The fluorescence quantum yield has been determined in various solvents and ratio of excited state dipole moment to ground state dipole moment has been determined using solvatochromic method. The compound can be used as efficient fluorescent material in ultraviolet range.

Three isomeric A-type proanthocyanidins have been isolated from the root of Prunus armeniaca . They were identified as ent -epiafzelechin-(4α→8; 2α→O→7)-epiafzelechin (mahuannin A), ent -epiafzelechin-(4α→8; 2α→O→7)-(+)-afzelechin and ent -epiafzelechin-(4α→8; 2α→O→7)-(−)-afzelechin, by means of spectral studies.

A field survey in Prunus armeniaca growing areas of Garhwal Himalaya was conducted with reference to the germination and growth of some companion crops at various sites of different soil fertility. Retardation in germination, growth and yield were noted in nearby Triticum aestivum plants, particularly on those sites where the percentage of soil organic matter was low. It was also observed that the magnitude of interference gradually decreased as the distance from the tree increased. Aqueous and organic solvent extracts of the aerial parts of Prunus armeniaca were made and their residues were tested, after proper dilution, for their phytotoxic effect on germination and growth of the test crop. Residues of light petroleum and ethyl acetate extracts showed maximum inhibition in growth and germination of the test species. The isolated compounds were identified with the help of spectroscopic techniques and bioassays. β -Sito-sterol, 2,6-dihydroxy-4-methoxyacetophenone and kaempferol were isolated from a petroleum extract whereas aromadendrin, quercetin, β -sitosterol- β - d -glucoside, pleoside and tannins (four proanthocyanidins – A-type) were characterized from an ethyl acetate extract. Of these, proanthocyanidins showed maximum inhibition, whereas quercetin, aromadendrin, kaempferol and genin of pleoside inhibited to a lesser extent.

A glycoside extracted from the rhizomes of Agave americana was identified as 3-O-[{{β-D-xylosyl(1 3)}{β-D-xylosyl(1 3) - β - D - glucopyranosyl(1 2)} - β - D - glucopyranosyl(1 4)} - β - D - galactopyranosyl] - (25R) - 5α - spirostan-3β-ol by concerted use of proton and carbon-13 2D NMR methods. Complete assignments for the sugar resonances were obtained with standard methods, but the presence of chemical shift degeneracies prevented an unequivocal determination of two of the glycosidic linkage points by the HMBC experiment. Further two-dimensional experiments failed to resolve the ambiguity, but a clear identification of the linkages was obtained using a selective reverse INEPT experiment with homonuclear double resonance.

Micro and macro elements such as Zn, Cu, Mn, Fe, Co, Na, K, Ca and Li were detected from Rheum moorcroftianum Royle, a plant used in folk medicines. Altitudinal and seasonal variation of these trace elements in cultivated and wild roots and leaves of R. moorcroftianum were quantified by atomic absorption spectroscopy. The highest concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca and Li were found to be 376.0 ± 0.9, 83.0 ± 4.6, 322.0 ± 6.0, 920.0 ± 1.9, 72.0 ± 1.5, 402.0 ± 7.8, 10,235.0 ± 7.0, 12,336.0 ± 2.6 and 59.9 ± 0.3 mg kg(-1), respectively, in all the samples analysed.

A series of 2-pyrazolines have been synthesized from α, β unsaturated ketones and hydrazine hydrate with acetic/formic acid in ethanol/DMSO. The structures of 2-pyrazolines have been established by spectroscopic techniques i.e. UV, IR, 1H NMR, 13C NMR and micro element analysis. Fluorescence spectra were recorded in the solution at fixed concentration and same excitation wavelength at 290 nm. The absorption band positions of all the compounds broadly lie between 280 and 336 nm and fluorescence band positions in the range between 300 and 370 nm, the near ultraviolet region.

The concerted use of 1D and 2D multiple pulse NMR methods allowed the identification and assignment of a proanthocyanidin, ent-epiafzelechin(4α → 8; 2α → O → 7)-epicatechin, extracted from the bark of Prunus jacquemontii. Reference deconvolution with the FIDDLE algorithm was successfully used for line shape correction of a 13C spectrum with poor signal-to-noise ratio. Over 70 long-range proton– 13C correlations were determined with the HMBC experiment, following modifications to improve instrument signal reproducibility, illustrating the value of this experiment when applied to systems with relatively few protons.

Variations of micro- and macrominerals concentration in Swertia speciosa were determined by atomic absorption spectroscopy. The mineral elements showed significant changes in roots and leaves collected from different altitudes. Among all the elements, highest concentration (more than 2,000 mg/kg) of Ca and K were recorded in S. speciosa and the concentration of other elements analyzed in the study decreased in the order Fe>Na>Zn>Co>Li>Cu>Mn.

Present investigation was carried out to estimate mineral elements in Rheum emodi Wallr. by atomic absorption spectroscopy. The samples of R. emodi Wallr., both wild and cultivate populations, were collected from different localities at different altitudes of Uttarakhand, India. The concentration of micro- and macroelements was different in roots and leaves. The concentration of mineral elements was found in both the leaves and roots in the order of K > Ca > Fe > Mn > Na > Zn > Co > Li > Cu.

Concentration level of nine elements viz. Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li were determined in leaves and roots of Asparagus curillus (Buch.-Ham.) ex Roxb. collected from four different altitudes in three seasons by atomic absorption spectroscopy. The overall concentration of K was found to be highest, whereas the level of Cu was lowest. The maximum concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li were found to be 97.0 +/- 1.5, 28.0 +/- 7.0, 44.0 +/- 7.3, 1138.0 +/- 18.5, 91.0 +/- 6.2, 381.0 +/- 7.8, 9508.0 +/- 7.8, 3076.0 +/- 6.4, and 78.0 +/- 4.6 mg/kg, respectively.

Reaction of dibenzalacetone with hydrazine hydrate and formic acid yielded a novel 2-pyrazoline 1 , characterized by ESI-MS, FT-IR, UV, 1 HNMR and 13 CNMR data and microanalysis. Keywords: dibenzalacetone; hydrazine hydrate; pyrazoline; 5-phenyl-3-[( E )-2-phenyl-vinyl]-4,5-dihydro-1 H -pyrazole-1-carbaldehyde; fluorescence Introduction Substituted pyrazolines are useful in pharmaceutical and agrochemical research. Pyrazoline derivatives with a phenyl group at the 5-position possess good film-forming properties, exhibit excellent characteristics of blue photoluminescence and electroluminescence [1]. Pyrazolines are also used as optical brighteners and whiteners. Pyrazolines display various biological activities such as antimicrobial [2], antifungal [3], antidepressant [4], immunosuppressive [5], anticonvulsant [6], anti-tumor [7], antiamoebic [8], antibacterial [9] and antiinflammatory [10] activities. Syntheses of pyrazolines by reaction of α,β-unsaturated carbonyl compounds with diazoalkanes [11] or with hydrazine hydrate [12,13] were reported in literature. N-Substituted thiocarbamoyl-3,5-diphenyl-2-pyrazoline derivatives having NS donor, their palladium II complexes [14] and hydroxyl phenyl pyrazolines have also been synthesized [15]. The reaction of

A new aliphatic ester, pentacosanyl heptacosanoate was isolated from Polygonum polystachyum Wallich. alongwith five known compounds heptacosanoic acid, β-sitosterol, β-sitosterol-β-D-glucoside, quercetin, querectin-3-O-L-rhamnopyranoside. Structures of the isolated coin pounds were established by the application of spectroscopic techniques.

A new iridoid glycoside, premnosidic acid (compound 1) has been isolated from Premna barbata Wallich and characterized with the help of FAB-MS, 1 H NMR, 1 3 C NMR, HMQC, HMBC and NOE experiments.

A new secoiridoid glycoside, 6′- O -β-apiofuranosylsweroside ( 1 ), together with the known compounds sweroside, loganin, β-sitosterol, oleanolic acid, ursolic acid and methyl-4-hydroxy benzoate have been identified from the leaves of Lonicera angustifolia . The structure of the new compound has been elucidated on the basis of spectroscopic and chemical evidence.

1,2,6,8-Tetrahydroxyxanthone (SR1) and 2,8-dihydroxy-1,6-dimethoxyxanthone (SR2) have been qualitatively and quantitatively determined in leaves and rhizomes of Swertia paniculata. The methanol extracts were analyzed on a C18 column using MeOH and H2O as mobile phase at a flow rate of 1 mL/min. Identification was achieved using an UV variable Λ detector set at 260 nm. Variation in the bioactive compounds with respect to season and altitude was determined, along with the examination of the antidiabetic activity of the plant. The maximum concentration of SR1 and SR2 was found in leaves collected from Tungnath (3600 m), Uttarakhand, India, in October. The blood sugar level in alloxan induced rats was decreased by 51.0% by the methanol extract of the leaves. Overall, results showed that the concentration of bioactive compounds increased with altitude. October was the period of prime potency and should be the time of harvest for S. paniculata.

High performance liquid chromatography (RP-HPLC) method was developed and validated for the determination of two xanthones, 1,2,6,8-tetrahydroxyxanthone (SR1) and 2,8-dihydroxy-1,6-dimethoxyxanthone (SR2) in leaves and rhizomes of Swertia speciosa. The extracts were analyzed on C18 column using an isocratic mobile phase which consists of MeOH and H2O at the flow rate of 1 ml/min. Identification of xanthone derivatives was done by using UV variable λ detector at 260 nm. The limit of detection obtained for the analytes were in the range of 0.86–2.24 ppm. We had planned to quantify the major bioactives in S. speciosa and to compare their variation with seasons and altitudes. Maximum concentration of SR1 and SR2 was found in S. speciosa rhizomes collected from Hemkund (4000 m high), Uttarakhand, India. Overall, results show that the concentration of bioactives increase with altitude and in samples collected in between Sep.-Oct. which seems to be the period of prime potency and should be the harvesting period.

The chromatographic profile of xanthones found in Swertia chirata was studied by HPLC using a C18 reversed phase column and aqueous methanol mobile phase using UV absorption at 260 nm. RP-HPLC method was developed and validated for the determination of two xanthone derivatives, 2, 8-dihydroxy-1, 6-dimethoxyxanthone (SR1) and 1, 2, 6, 8-tetrahydroxyxanthone (SR2) in leaves and rhizomes of S. chirata. The HPLC fingerprints of four batches of herbal samples from different regions of Uttarakhand Himalaya showed similar chromatographic patterns. The retention time of markers peak in the HPLC fingerprint were determined as an important parameter for identification. In this herb, SR1 and SR2 were quantitatively determined using a validated reversed phase HPLC method. The bioactives of S. chirata were quantified and their variation was studied in cultivated and wild species with season and altitude to infer about prime of potency and proper harvesting period. The limit of detection obtained for the analytes were in the range of 0.86–2.24 ppm and the maximum concentration of xanthones was found in cultivated plants.

A new flavanone glycoside, persicogenin 3′-glucoside (5,3′-dihydroxy-7,4′-dimethyoxyflavanone 3′-glucoside) has been characterized from the stem bark of Prunus amygdalus .

A new methyl ester of melilotoside, methyl-o-coumarate-β-d-glucoside, has been characterized from the sapwood of Prunus cornuta.

A new betulinic acid glycoside, lup-20(29)-en-28-oic-3-O-β- d -glucopyranosyl (2→1)-O-β- d -glucopyranoside has been characterized from the leaves of Schefflera venulosa.

Complete 13C and 1H assignments for the oligosaccharide segment of a novel spirostanol glycoside were derived, and structural proof obtained, using a combination of DEPT, heteronuclear chemical shift correlation, homonuclear relayed coherence transfer, absolute value COSY, phase-sensitive double quantum filtered COSY, NOESY, INEPT and proton-detected long-range heteronuclear shift correlation via multiple quantum coherence.

A spirostanol glycoside was isolated, together with some known compounds, from the methanolic extract of the fruits of Asparagus officinalis and characterized by chemical and spectral methods including 13 C NMR-DEPT and 2D-hetcor NMR spectra. The spirostanol glycoside caused 100% immobilization of human spermatozoa at 1.5% level.

A new ruscogenin glycoside has been characterized from the rhizomes of Ophiopogon intermedius.