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Lot of attention is focused on the development of value-added foods that promote wellbeing and improve health due to increased awareness among consumers, rapid urbanization and globalization. Many by-products may be useful as source of nutrients and potential functional ingredients to obtain added value products for combating hidden hunger. Cauliflower (Brassica oleracea) has highest waste index with maximum ratio of non-edible to edible portion after harvesting. Unfortunately, cauliflower waste in developing countries like India does not find any significant use despite containing appreciable amounts of proteins, minerals, vitamins, dietary fibre and natural antioxidants like carotenoids, phenolic compounds, glycosylates and flavonoids. Thus, it can be a novel ingredient for production of value-added foods. The cauliflower stalks powder was incorporated to phulkas at 5, 10 and 15% respectively and evaluated by semi trained panellists using 5-point hedonic scale for colour, flavour, texture, taste and overall acceptability. The phulkas with 10% incorporation was most accepted one. The most accepted phulkas was screened for phytochemical constituents and analysed for physical parameters. The results showed that the cauliflower stalks incorporated phulkas contained phytochemicals like carbohydrates, alkaloids, protein, flavonoids, phenols, amino acids, cardiac glycosides, steroids, saponins and tannins. The physical parameters included foaming properties, swelling capacity, gelatinization temperature which were higher for cauliflower stalks incorporated phulkas whereas water uptake analysis, cooking time, retrogradation was lower in comparison to control phulkas.

In the present investigation 2-(hydrazinylmethyl)-1,3-benzothiazole was reacted with aryl aldehyde to give 2-{[2Z)-2-arylhydrazinyl]methyl}-1,3-benzothiazole (3a-f), which in absolute ethanol treated with thioglycolic acid (0.001 mol) and anhydrous zinc chloride under reflux for 8 hr to get 3-[1,3-benzothiazol-2-ylmethyl) amino]-5-(aryl)-1,3-thiazolidin-2-ones (4a-f). On the other hand [Benzothiozole N-aryl thiozolemethanamines] (5a-f) were obtained, when the compounds (3a-f), are treated with diazomethane.

In the present work, the effect of process parameters on joining of AZ91 Mg alloy and Al6063 aluminum alloy sheets during friction stir welding (FSP) was studied. A successful joint was achieved at 1100 r.p.m. tool rotational speed and 25 mm/min tool travel speed. Combination of tool rotational speed and tool travel speed has observed a profound effect on the material flow mechanisms at the nugget zone. From the microstructural studies, the joint formation was observed as mainly due to mechanical mixing of the materials. The level of metallurgical continuity at the nugget zone was observed as poor and a sharp interface at the joint was noticed. The microhardness measurements across the weld joint also revealed the lack of establishment of a perfect metallurgical bonding. X-ray diffraction analysis of weld zone showed presence of both magnesium and aluminum. Hence from the preliminary observations, it can be understood that the joining of AZ91 Mg alloy and Al6063 alloy can be achieved by FSP; however, complex issues in material mixing still need further investigations. Keywords: Friction stir welding, Dissimilar joints, Magnesium, Aluminum, Nugget zone

The self-assembly process of a Pd2L4 cage consisting of flexible ditopic ligands and Pd(II) ions was revealed by QASAP (quantitative analysis of self-assembly process), which enables one to obtain information about the intermediates transiently produced during the self-assembly as the average composition of all the intermediates. It was found that the dominant pathway to the cage is the formation of a submicrometre-sized sheet structure, which was characterized by dynamic light scattering (DLS) and scanning transmission electron microscopy (STEM), followed by the addition of free ditopic ligands to the Pd(II) centres of the sheet structure to trigger the cage formation. This assembly process is completely different from that of a Pd2L4 cage composed of rigid ditopic ligands, indicating that the flexibility of the components strongly affects the self-assembly process.

Unique heterogeneous catalase-like activity was observed for metallosupramolecular ionic crystals [AuI4CoIII2(dppe)2(d-pen)4]X n ([1]X n ; dppe = 1,2-bis(diphenylphosphino)ethane; d-pen = d-penicillaminate; X n = (Cl-)2, (ClO4-)2, (NO3-)2 or SO42-) consisting of AuI4CoIII2 complex cations, [1]2+, and inorganic anions, X- or X2-. Treatment of the ionic crystals with an aqueous H2O2 solution led to considerable O2 evolution with a high turnover frequency of 1.4 × 105 h-1 for the heterogeneous cobalt complexes, which was dependent on their size and shape as well as the arrangement of cationic and anionic species. These dependencies were rationalized by the presence of cobalt(ii) centers on the crystal surface and their efficient exposure on the (111) plane rather than the (100) plane based on morphological and theoretical studies.

Rebaudioside D3, a novel steviol glycoside, is produced by specific UDP-glycosyltransferase of rebaudioside E, a minor steviol glycoside of Stevia rebaudiana Bertoni. The complete proton and carbon NMR spectral assignments of rebaudioside D3, 13-[(2-O-β-D-glucopyranosyl-6-O-β-D-glucopyranosyl-β-D-glucopyranosyl) oxy] ent-kaur-16-en-19-oic acid-(2-O-β-D-glucopyranosyl-β-D-glucopyranosyl) ester, was achieved by the extensive 1D and 2D NMR (1H and 13C, TOCSY, HMQC, HMBC) as well as mass spectral data. Further, hydrolysis studies were performed on rebaudioside D3 using acid and enzymatic studies to identify aglycone and sugar residues in its structure. Rebaudioside D3 is detected in the commercial extract of the leaves of Stevia rebaudiana by LC-MS analysis, suggesting rebaudioside D3 is a natural steviol glycoside.

A new steviol diterpene glycoside, 13-[(2-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-{2-O-[6-O-β-D-glucopyranosyl)-β-D-glucopyranosyl]-β-D-glucopyranosyl} ester (1) has been isolated from the commercial extract of the leaves of Stevia rebaudi-ana Bertoni. Structure of the new compound has been established on the basis of extensive NMR spectroscopy (1H &13C, TOCSY, HMQC, and HMBC) and High Resolution (HR) mass spectroscopic data as well as enzymatic and acid hydrolysis studies.

The heterogeneous catalase-like activity of ionic crystals consisting of AuI 4CoIII 2 complex cations is studied along with their surface morphologies and oxidation states., Unique heterogeneous catalase-like activity was observed for metallosupramolecular ionic crystals [AuI 4CoIII 2(dppe)2(d-pen)4]Xn ([1]Xn; dppe = 1,2-bis(diphenylphosphino)ethane; d-pen = d-penicillaminate; Xn = (Cl–)2, (ClO4 –)2, (NO3 –)2 or SO4 2–) consisting of AuI 4CoIII 2 complex cations, [1]2+, and inorganic anions, X– or X2–. Treatment of the ionic crystals with an aqueous H2O2 solution led to considerable O2 evolution with a high turnover frequency of 1.4 × 105 h–1 for the heterogeneous cobalt complexes, which was dependent on their size and shape as well as the arrangement of cationic and anionic species. These dependencies were rationalized by the presence of cobalt(ii) centers on the crystal surface and their efficient exposure on the (111) plane rather than the (100) plane based on morphological and theoretical studies.

Intracellular protein (BSA) delivery by a phosphonate@mesoporous silica nanoparticle vehicle, PMSN, with high load capacity for the relatively large test protein BSA, is described. Wide pore (11.6 nm) PMSN nanoparticles were synthesised and loaded with a BSA cargo to give BSA#@PMSN*, where # and * signify Fluorescein and Rhodamine fluorescent labels respectively. Internalisation of BSA#@PMSN*s by HeLa cells was analysed from confocal microscopy and TEM images after dose and time dependent treatments. No evidence of cytotoxicity was observed after 24 h and in contrast to PMSN* no significant loss of BSA#@PMSN* was observed after 3 h incubation of the loaded cells in DMEM. Receptor blocking experiments showed caveolar uptake of PMSN* and folate receptor mediated uptake of BSA#@PMSN*s.

Four new minor diterpene glycosides with a rare α-glucosyl linkage were isolated from a cyclodextrin glycosyltransferase glucosylated stevia extract containing more than 98% steviol glycosides. The new compounds were identified as 13-[(2-O-β-d-glucopyranosyl-3-O-(4-O-α-d-glucopyranosyl)-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[(4-O-α-d-glucopyranosyl-β-d-glucopyranosyl) ester] (1), 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[(4-O-(4-O-(4-O-α-d-glucopyranosyl)-α-d-glucopyranosyl)-α-d-glucopyranosyl)-β-d-glucopyranosyl ester] (2), 13-[(2-O-β-d-glucopyranosyl-3-O-(4-O-(4-O-(4-O-α-d-glucopyranosyl)-α-d-glucopyranosyl)-α-d-glucopyranosyl)-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester (3), and 13-[(2-O-β-d-glucopyranosyl-3-O-(4-O-(4-O-(4-O-α-d-glucopyranosyl)-α-d-glucopyranosyl)-α-d-glucopyranosyl)-β-d-glucopyranosyl- β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[(4-O-α-d-glucopyranosyl-β-d-glucopyranosyl) ester] (4) on the basis of extensive NMR and mass spectral (MS) data as well as hydrolysis studies.

Introduction: White spot lesions are a major problem in orthodontic patients as they compromise esthetics. They are the result of decalcification of enamel that occurs around brackets. This in vivo study was conducted to evaluate the effect of three different forms of topical fluoride on enamel demineralization adjacent to bonded brackets. Materials and methods: A total of 24 patients who needed extraction of at least two premolars for orthodontic reasons were selected. In each patient, one premolar was the test tooth and the other was the control. Brackets were bonded but only the test teeth received topical fluoride, that is, Transbond PLUS Color Change Adhesive, bifluoride12, GC Tooth Mousse Plus. The premolars were extracted after 80 to 90 days, and buccolingual sections 50 to 70 μm in thickness were evaluated with polarized light microscopy. The mean depth of demineralization in each lesion was measured using the software Image Pro Plus. Results: The difference between the values of the depth of demineralization in the experimental and control samples of all groups was found to be statistically significant (p < 0.05). There was a 43.3% reduction in the lesion depth in the transbond plus group. There was a 67.4% reduction in the lesion depth in the GC tooth mousse group. There was a 70% reduction in the lesion depth in the bifluoride varnish group. Conclusion: Enamel demineralization around brackets is signi­ ficantly reduced by all the three materials used in this study. The highest amount of lesion depth reduction was seen in the Bifluoride varnish group. Transbond plus, was the least effective among the three materials used.

Continuous phytochemical studies of the crude extract of Luo Han Guo (Siraitia grosvenorii) furnished three additional new cucurbitane triterpene glycosides, namely 11-deoxymogroside V, 11-deoxyisomogroside V, and 11-deoxymogroside VI. The structures of all the isolated compounds were characterized on the basis of extensive NMR and mass spectral data as well as hydrolysis studies. The complete 1H- and 13C-NMR spectral assignments of the three unknown compounds are reported for the first time based on COSY, TOCSY, HSQC, and HMBC spectroscopic data.

Degradation of rebaudioside M, a minor sweet component of Stevia rebaudiana Bertoni, under conditions that simulated extreme pH and temperature conditions has been studied. Thus, rebaudioside M was treated with 0.1 M phosphoric acid solution (pH 2.0) and 80 °C temperature for 24 h. Experimental results indicated that rebaudioside M under low pH and higher temperature yielded three minor degradation compounds, whose structural characterization was performed on the basis of 1D (1H-, 13C-) & 2D (COSY, HSQC, HMBC) NMR, HRMS, MS/MS spectral data as well as enzymatic and acid hydrolysis studies.

This paper reports the synthesis of large pore (11 nm) monodisperse raspberry textured phosphonate@silica nanoparticles (70-90 nm) with high capacity for protein immobilization. The raspberry nanoparticles denoted RNP_PME(2.5) with phosphonate loading 2.5 mmol g-1, formed using an organosilanephosphonate (MeO)3SiCH2CH2PO(OMe)2, as silica surface modifier and structure directing agent. Specific reaction conditions including temperature and concentration of phosphonate, base, surfactant and co-solvent were required for RNP_PME(2.5) formation. Rhodamine B labelled RNP_PME(2.5) was readily internalised by HeLa cells with no deficit of cell viability. Aqueous dispersions of RNP_PME(2.5) were stable over several months. In protein immobilization studies using BSA, bovine serum albumin, with RNP_PME(2.5), smaller pore (∼3 nm) phosphonate@silica nanoparticles NP_PME(1.0) and NP_PME(0.2) and mesoporous silica nanoparticles, MSN, the large pore RNP_PME(2.5) gave highest BSA loading 266 mg g-1, formed the most stable aqueous dispersions (BSA@MSN was unstable and precipitated) and gave the best protection against BSA structural distortion at pH 7.4.

From the commercial extract of the leaves of Stevia rebaudiana Bertoni, a new minor ent-kaurane diterpene glycoside having five β-D-glucopyranosyl units has been isolated. The chemical structure of the new compound was characterized as 13-[(2-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-(2-O-β-D-glucopyranosyl-6-O-β-D-glucopyranosyl-β-D-glucopyranosyl) ester (1) on the basis of extensive 1D (1H & 13C) and 2D NMR (TOCSY, HMQC, and HMBC), and High Resolution (HR) mass spectroscopic data as well as hydrolysis studies.

High Performance Liquid Chromatography (HPLC) experiments have been performed on nine steviol glycosides namely rebaudioside A, steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, and dulcoside A isolated from the leaves of Stevia rebaudiana using Reversed-Phase (RP) column. Using RP-HPLC method, the individual retention times for nine naturally occurring ent-kaurane diterpene glycosides of S. rebaudiana reported in JECFA have been determined at four different temperatures: 20℃, 40℃, 60℃, and 79℃. Also, calculated the relative retention times of the eight steviol glycosides steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, and dulcoside A against the major steviol glycoside rebaudioside A. HPLC results suggested that temperatures 40℃ and 60℃ would be ideal conditions for better separation of steviol glycosides.

A simple easily scalable one-pot route to new phosphonic acid polysilsesquioxanes, PAPSQ, [(O 3/2 SiCH 2 R) x (O 3/2 SiCHR(CH 2 ) 2 SiO 3/2 ) y ] n where R = CH 2 PO 3 H 2 , is described in this paper. Nuclear magnetic resonance (NMR), electron microscopy (SEM), thermogravimetric analysis, nitrogen sorption porosimetry, phosphorus and available acid analysis were used to characterise the new PAPSQ materials. The materials were shown to be very efficient and recyclable mild solid acid catalysts for organic transformations including those relevant to biomass conversion such as esterification, transesterification and dehydration of fructose to the important intermediate 5-hydroxymethylfurfural.

The complete proton and carbon NMR spectral assignments of a diterpene glycoside isolated from the commercial extract of the leaves of Stevia rebaudiana Bertoni, 13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] entkaur-16-en-19-oic acid-[(2-O-α-L-rhamnopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl) ester] (1); also known as rebaudioside N, was achieved by the extensive 1D and 2D NMR (1H and 13C, COSY, HMQC, HMBC) as well as mass spectral data. Further, hydrolysis studies were performed on rebaudioside N using acid and enzymatic studies to identify aglycone and sugar residues in its structure.

Purification of the dichloromethane (CH2Cl2) fraction of the aqueous extract of Rubus suavissimus resulted in the isolation of two sterols namely stigmasterol and ?-sitosterol. The structures of the isolated compounds were characterized on the basis of extensive spectral data (1D and 2D NMR; and MS) and in comparison with their literature data.DOI: http://dx.doi.org/10.3329/icpj.v1i9.11613 International Current Pharmaceutical Journal 2012, 1(9): 239-242

Stability of rebaudioside A, a sweet component of Stevia rebaudiana was studied covering a typical pH range 2.8–4.2 that simulated both relevant and extreme beverage storage conditions. Thus, rebaudioside A was evaluated in mock beverage solutions by simulating formulations used in commercial cola soft drinks (pH 2.8 and pH 3.2), lemon–lime soft drinks (pH 3.8), and root beer soft drinks (pH 4.2) but lacking the flavor components. The mock beverage samples, formulated at ~ 500 mg/l were subjected to various temperature conditions (5, 20, 30, and 40 °C) for 26-weeks at each pH. Samples were analyzed at scheduled intervals throughout the 26-week period for rebaudioside A, its known impurities and degradation products. Experimental results indicated that rebaudioside A yielded six minor degradation compounds whose structural characterization was performed on the basis of 1D ( 1 H, 13 C) and 2D (COSY, HSQC, HMBC) NMR, HRMS, MS/MS spectral data as well as enzymatic and acid hydrolysis studies.

The objective is to identify the Infra-Red (IR) spectral analysis of the diterpene glycosides present in the commercial extracts of Stevia rebaudiana was achieved by PerkinElmer Spectrum 400 Fourier Transform (FT) spectrometer employing a PerkinElmer Universal Attenuated Total Reflection (ATR) accessory. Using this technique the IR spectral pattern of 15 steviol glycosides which belongs to three different classes of ent-kaurane diterpene glycosides namely ent-13-hydroxykaur-16-en-19-oic acid, ent-13-hydroxykaur-15-en-19-oic acid, and 13-methyl-16-oxo-17-norent- kauran-19-oic acid were identified. From the wave numbers found for all 15 steviol glycosides, it was observed that that though there are differences in the number of sugar units, nature of sugar units, and their attachments; there are not any notable differences in the IR values.

Synthesis of two ent-kaurane diterpene glycosides, steviol 19-O-β-D-glucopyranosiduronic acid (steviol glucuronide, 5 ), and 13-hydroxy ent-kaur-16-en-19-oic acid-β-D-glucopyranosyl ester (7) has been achieved from a common starting material, steviol, using phase transfer catalyst. Also, synthesis of an additional 17-nor-ent-kaurane glycoside, namely 13-methyl-16-oxo-17-nor-ent-kauran-19-oic acid-β-D-glucopyranosyl ester (10) was performed using the starting material isosteviol and similar synthetic methodology. Synthesis of all three steviol glycosides was performed using straightforward chemistry and their structures were characterized on the basis of 1D and 2D NMR as well as mass spectral (MS) data.

From the commercial extract of the leaves of Stevia rebaudiana, three new diterpenoid glycosides were isolated besides eight known steviol glycosides including stevioside, rebaudiosides A–F and dulcoside A. The structures of the three compounds were identified as 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl) oxy]-kaur-16-en-18-oic acid-(6-O-β-d-xylopyranosyl-β-d-glucopyranosyl) ester (1), 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl) oxy]-17-hydroxy-kaur-15-en-18-oic acid β-d-glucopyranosyl ester (2), and 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl) oxy]-17-oxo-kaur-15-en-18-oic acid β-d-glucopyranosyl ester (3) on the basis of extensive NMR and MS spectral studies. Another known diterpenoid glycoside, 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl) oxy]-kaur-15-en-18-oic acid β-d-glucopyranosyl ester (4) was also isolated and its complete NMR spectral assignments were made on the basis of COSY, HSQC and HMBC spectral data.

From the commercial extract of the leaves of Stevia rebaudiana, two new minor diterpene glycosides having α-glucosyl linkage were isolated besides the known steviol glycosides including stevioside, steviolbioside, rebaudiosides A-F, rubusoside and dulcoside A. The structures of the two compounds were identified as 13-[(2-O-(3-α-O-d-glucopyranosyl)-β-d-glucopyranosyl-3-O-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester (1), and 13-[(2-O-β-d-glucopyranosyl-3-O-(4-O-α-d-glucopyranosyl)-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester (2), on the basis of extensive NMR and MS spectral data as well as chemical studies.

From the commercial extract of the leaves of Stevia rebaudiana , two new diterpenoid glycosides were isolated besides the known steviol glycosides including stevioside, rebaudiosides A–F, rubusoside, and dulcoside A. The structures of the two new compounds were identified as 13-[(2- O -6-deoxy-β- d -glucopyranosyl-β- d -glucopyranosyl)oxy] ent -kaur-16-en-19-oic acid β- d -glucopyranosyl ester ( 1 ), and 13-[(2- O -6-deoxy-β- d -glucopyranosyl-3- O -β- d -glucopyranosyl-β- d -glucopyranosyl)oxy] ent -kaur-16-en-19-oic acid β- d -glucopyranosyl ester ( 2 ), on the basis of extensive NMR and MS spectral data as well as chemical studies.

From the commercial extract of the leaves of Stevia rebaudiana, a new diterpene glycoside was isolated besides the known steviol glycosides including stevioside, rebaudiosides A-F, rubusoside and dulcoside A. The new compound was identified as 13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-(2-O-α-L-rhamnopyranosyl-β-D-glucopyranosyl) ester (1) on the basis of extensive spectroscopic (NMR and MS) and chemical studies.

Systematic phytochemical studies of the extract of Luo Han Go (Siraitia grosvenorii) furnished six known cucurbitane glycosides, namely, mogrosides IVa, mogrosides V and VI, isomogroside V, 11-oxomogroside V, and siamenoside I. The structures of all the isolated compounds were characterized on the basis of extensive spectral and chemical studies. Though the partial NMR spectral data has been reported for some of the isolated compounds previously, the complete 1H and 13C NMR spectral assignments of all the isolated compounds are reported herewith for the first time based on COSY, HSQC, HMBC, and NOESY spectroscopic data.

A new diterpene glycoside with six β-D-glucopyranosyl units was isolated from the extract of the leaves of Stevia rebaudiana Bertoni, which was identified as 13-[(2- O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[2- O-β-D-glucopyranosyl-3- O-(2- O-β-D-glucopyranosyl)-β-D-glucopyrano-syl -β-D-glucopyranosyl) ester (1) based on the extensive NMR (1H and 13C, COSY, HSQC, and HMBC) and mass spectral data as well as hydrolysis studies.

Iodination of certain aromatic amines and phenols are triggered by the oxidation of KI by peroxy compounds such as tert-butyl hydroperoxide (tBuOOH) under liquid-phase and solvent-free conditions by grinding the reactants in a mortar with a pestle. The reactions afforded corresponding iodo derivatives in good yield with high regioselectivity (Table 1).

A new minor diterpene glycoside has been isolated from a commercial extract of the leaves of Stevia rebaudiana and its structure was identified as 13-[(2-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[2-O-(2-O-β-D-glucopyranosyl)-β-D-glucopyranosyl-3-O-b-D-glucopyranosyl-β-D-glucopyranosyl] ester (1) based on extensive NMR (1D and 2D) and mass spectroscopic data, and hydrolysis studies.

Co-SBA-15 catalysts were synthesized by direct synthesis and post-synthetic impregnation methods at two different loadings of Co viz., 1.2 and 2 wt%. The structure of SBA-15 was found to remain intact even after the incorporation of Co in either of the two methods of catalyst preparation, which was confirmed by low-angle XRD. The existence of Co2+ species were confirmed by characteristic absorption bands of Co in the UV–vis spectra and XPS results. The encapsulation of Co in SBA-15 was found to be highly advantageous in yielding significant amounts of the desired products viz., cyclohexanone and cyclohexanol in the oxidation of cyclohexane in liquid phase without using any solvent under moderate pressure of O2 at 433 K. The catalysts showed high turn over numbers towards the oxidation of cyclohexane to cyclohexanone and 2%CoSYN (2 wt% Co-SBA-15) catalyst showed a maximum of 9.4% conversion of cyclohexane and 78% selectivity towards the formation of cyclohexanone.

In the present work, we report conversion of fluoxetine (Prozac), a novel anti depressant to N-methyl fluoxetine in formalin fixed liver tissue. Earlier studies indicate that drugs containing secondary amino group will react with formalin to form corresponding N-methyl derivatives. Even though embalming cadavers is common, it may create problems for forensic toxicologists if a case was not previously suspected. In formalin solutions, fluoxetine is methylated producing N-methyl fluoxetine. N-Methyl fluoxetine standard was synthesized by treating fluoxetine in formaldehyde solution. The structure confirmed by (1)HNMR and gas chromatography-mass spectrometry in electron impact ionization mode. Randomly chosen rat liver pieces (200-250 mg) were injected with 100 microg of Fluoxetine. The liver pieces were covered with three different concentrations of formalin, 5%, 10%, and 20%, and at three different pHs, 3.0, 7.0, and 9.5. The reaction was studied for a total period of 30 days, and the reaction products were monitored on days 0, 4, 14, and 30 days. The study indicates that the rate of conversion of fluoxetine to its N-methyl derivative increased with increase in the concentration of formalin and pH of the solution. The conversion is rapid at higher pH values. Fluoxetine was totally converted to its N-methyl derivatives after 30 days in 20% formalin at pH 9.5. Therefore, analysis for parent drug or its N-methyl derivative in embalmed tissues may provide data that will reduce the likelihood of false negatives.

Zoloft (sertraline hydrochloride) is one of the antidepressant medications used to treat depression, obsessive-compulsive disorder, and social anxiety disorder. The practice of embalming a cadaver is common, yet it may create problems for forensic toxicologists if the case was not previously suspected to involve drug overdose. According to the Eschweiler-Clarke reaction, drugs containing a secondary amine group react with formaldehyde to give N-methyl derivatives. Sertraline has a secondary amine group; therefore, we predicted that it may react with formalin to give N-methyl derivatives. The stability of sertraline in formalin solution was studied at three different concentrations (5%, 10%, and 20%) and at three different pHs (3.0, 7.0, and 9.5) for a period of 30 days. Setraline and its degraded products were extracted by liquid-liquid extraction using chloroform, and the concentrated extracts were analyzed by gas chromatography-mass spectrometry using electron impact ionization mode. The rate of conversion is rapid at higher pH. Sertraline was totally converted to the N-methyl derivative after 30 days in 10% and 20% formalin solutions at neutral and basic conditions. Therefore, forensic toxicologists should be cautious when performing a death investigation if formalin solution is the only sample available for analysis. This work shows that analysis for parent drug or its N-methyl derivative may provide data that will reduce the likelihood of false negatives.

A stability study has been initiated for propoxur (Baygon) in whole blood and urine samples stored over a period of 60 days at four different temperature conditions (room temperature, 4 degrees C, -20 degrees C, and -80 degrees C). Stability data was established on day 0, 1, 7, 14, 28, 42, and 60. Sample purification was done by solid-phase extraction using a weak cation exchange cartridge (Isolute CBA), and quantitation was carried out by a validated high-performance liquid chromatographic method with a photodiode-array UV detector. Propoxur was spiked at two different concentration levels in both blood and urine samples [low concentration (10 microg/L) and high concentration (100 microg/L)]. Isopropoxy phenol was observed as the major degradation product in blood and urine samples and confirmed by liquid chromatography-electrospray ionization-mass spectrometry. At room temperature, a substantial decrease in concentration of about 95% was observed at the end of the stability study in both blood and urine samples. However, at 4 degrees C, the concentration of propoxur observed after 60 days was around 60% in both samples. A decrease in temperature reduced the degradation, and finally propoxur was found to be stable at -80 degrees C and -20 degrees C for the whole observation period (60 days). The data collected suggests that knowledge about time-dependent decrease of propoxur in urine and blood samples is of considerable significance in forensic toxicology, and, therefore, forensic cases should be interpreted with caution.

Bioassay-guided fractionation of a CH(2)Cl(2)/MeOH extract of the bark of Casearia lucida resulted in the isolation of 11 new clerodane diterpenes, namely, casearlucins A-K (1-11), and three known clerodane diterpenoids, rel-(2S,5R,6R,8S,9S,10R,18S,19R)-diacetoxy-18,19-epoxy-6-hydroxy-2-(2xi-methylbutanoyloxy)cleroda-3,13(16),14-triene (12), rel-(2S,5R,6R,8S,9S,10R,18S,19R)-18,19-diacetoxy-18,19-epoxy-6-methoxy-2-(2xi-methylbutanoyloxy)cleroda-3,13(16),14-triene (13), and rel-(2S,5R,8S,9S,10R,18S,19R)-18,19-diacetoxy-18,19-epoxy-2-(2xi-methylbutanoyloxy)cleroda-3,13(16),14-triene (14). The structures of compounds 1-11 were established on the basis of extensive 1D and 2D NMR spectroscopic data interpretation. All compounds exhibited cytotoxicity activity against the A2780 ovarian cancer cell line, but none of the six compounds selected for testing in multiple cell lines showed significant selectivity.

The synthesis of (±)- trans -2-[3-methoxy-4-(chlorophenylthioethoxyphenyl)-5-cyanophenyl]-5-(3,4,5-trimethoxyphenyl)tetrahydrofuran from commercially available acetovanillone and 3,4,5-trimethoxybenzaldehyde is described.

Two additional novel minor diterpene glycosides were isolated from the commercial extract of the leaves of Stevia rebaudiana Bertoni. The structures of the new compounds were identified as 13-{β-D-glucopyranosyl-(1 → 2)-O-[β-D-glucopyranosyl-(1 → 3)-β-D-glucopyranosyl-oxy} ent-kaur-16-en-19-oic acid {β-D-xylopyranosyl-(1 → 2)-O-[β-D-glucopyranosyl-(1 → 3)]-O-β-D-glucupyranosyl-ester} (1), and 13-{β-D-6-deoxy-glucopyranosyl-(1 → 2)-O-[β-D-glucopyranosyl-(1 → 3)-β-D-glucopyranosyl-oxy} ent-kaur-16-en-19-oic acid {β-D-glucopyranosyl-(1 → 2)-O-[β-D-glucopyranosyl-(1 → 3)-β-D-gluco-pyranosyl-ester} (2), on the basis of extensive 1D (1H- and 13C-) 2D NMR (COSY, HSQC and HMBC) and MS spectroscopic data as well as chemical studies.

From the commercial extract of the leaves of Stevia rebaudiana Bertoni, a minor steviol glycoside, 13-[(2-O-β-D-glucopyranosyl-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[(2-O-(3-O-β-D-glucopyranosyl-α-L-rhamnopyranosyl)-3-O-β-D-glucopyranosyl-β-D-glucopyranosyl) ester] (1); also known as rebaudioside O having seven sugar units has been isolated. Its structural characterization has been achieved by the extensive 1D (1H and 13C), and 2D NMR (COSY, HMQC, HMBC) as well as mass spectral data. Further, hydrolysis studies were performed on rebaudioside O using acid and enzymatic methods to identify aglycone and sugar residues in its structure as well as their configurations.

Kinetics of oxidation of L-ascorbic acid (H2A) by sodium perborate (SPB) and peroxy disulphate (PDS) have been investigated in aqueous acid and micellar media. Reaction kinetics indicated first-order dependence on both |oxidant| and |H2A|. Increase in ionic strength (μ) increased reaction rate only in H2SO4 media. Rate of SPB oxidation of H2A has been accelerated by acidity in HNO3 and HCl media while a decreasing trend is observed in HClO4 and H2SO4 media. The results are interpreted by various theories of acidity functions. Reaction rate is enhanced by the addition of added |H2O2| indicating a H2O2 coordinated boron species to be active in the present system. In the absence of micelle, increase in |acid| altered the PDS(SINGLEBOND)H2A reaction rate marginally (a very small positive effect with HClO4 and negative effect with H2SO4). Most plausible mechanisms have been proposed on the basis of experimental results. Activation parameters evaluated for specific kinetic constants are in accord with outer sphere electron transfer mechanism. In SPB(SINGLEBOND)H2A system, addition of anionic micelle (Sodium lauryl sulfate) increased the rate, stabilizing the cationic species in the transition state in all the acid media. Although rate of PDS oxidation of H2A was catalyzed by TX and inhibited by SDS at critical micellar concentration (CMC) increase in |acid| (both HClO4 and H2SO4) beyond 9.6 × 10−4 M decreased the rate of oxidation. This trend was explained due to the repulsive interaction of coanion, HA−, and negatively charged micellar species. © 1996 John Wiley & Sons, Inc.

A kinetic study of the reaction of coumarin derivatives with Vilsmeier-Haack (VH) reagent (1:1 DMF-POCl3) in various solvent media revealed second-order kinetics with a first-order in [Substrate] and first-order in [VH reagent]. The reaction rates altered nonlinearly with an increase in the dielectric constant of the medium and the data did not fit completely well with either Amis or Kirkwood's theories of ion (SINGLEBOND) dipole and dipole (SINGLEBOND) dipole type reactions. On the basis of kinetic and spectroscopic results, participation of VH-adduct and coumarin molecule in the rate limiting step, has been proposed. Kinetic and activation parameters have been evaluated and discussed in terms of isokinetic relationship and as a function of solvent compositions. Linearity of Leffler's and Exner's plots indicate a similar type of mechanism to be operative in different dielectric media at all temperatures. © 1996 John Wiley & Sons, Inc.

Catalytic hydrogenation of the three ent-kaurane diterpene glycosides isolated from Stevia rebaudiana, namely rubusoside, stevioside, and rebaudioside-A has been carried out using Pd(OH)2 and their corresponding dihydro derivatives have been isolated as the products. Synthesis of reduced steviol glycosides was performed using straightforward chemistry and their structures were characterized on the basis of 1D and 2D NMR spectral data and chemical studies. Also, we report herewith the sensory evaluation of all the reduced compounds against their corresponding original steviol glycosides and sucrose for the sweetness property of these molecules.

Photostability of rebaudioside A, a sweet constituent of Stevia rebaudiana was studied under fluorescent light exposure at 25o C in mock beverages at pH 3.8 using International Conference on Harmonization (ICH) technical requirements covering the stability testing of new drug substances and products. Experimental results indicated that rebaudioside A did not undergo any major decomposition with fluorescent light exposure for 2 weeks. Identification of the degradation products furnished two minor compounds which were identified as 13-[(2-O-b-D-glucopyranosyl-3-O-b-D-glucopyranosyl]- b-D-glucopyranosyl)oxy]-17-hydroxy-ent-kaur-15-en-19-oic acid b-D-glucopyranosyl ester and 13-[(2-O-?-D-glucopyranosyl-3-O-?-D-glucopyranosyl-?-D-glucopyranosyl)oxy]-16?-hydroxy ent-kauran-19-oic acid b-D-glucopyranosyl ester on the basis of extensive spectroscopic data and chemical studies. Also, the mass balance for rebaudioside A was calculated against their control samples which were found 99.1%, suggesting any appreciable amount of undetected degradation products were formed under the conditions of the study.