The industrial and pharmaceutical applications of m onoesters of succinic anhydride have always p... more The industrial and pharmaceutical applications of m onoesters of succinic anhydride have always prompted the scientists for exploring new methods for the synthesis of the prod ucts without using toxic and expensive chemicals. H owever, up to now no significant approach has come forward. The avail able methods are not only ecologically unfriendly i .e. create heat, evolve toxic gases but also provide low yield. Ther efore, a new technique has been proposed in which t he opening of ring of succinic anhydride was performed by treating it with aryl alcohols, using p-toluenesulphonic acid as a catalyst and toluene as a solvent. In this way 1-27 monoesters of di-, and tri-substituted aryl alcoho ls have been synthesised with good yield; however, in case of 2,6-disubstituted alcoho ls the yield was considerably lower than others and was attributed to steric hindrance. The final products were purified using chromatographic techniques and their structur e was confirmed by recording IR, UV, 1D, 2D, ( 1 H- and 13 C-) NMR spectra, mass measurements and elemental analysis.
Industrial, pharmaceutical and daily life applicati ons of esters are countless; among these, the... more Industrial, pharmaceutical and daily life applicati ons of esters are countless; among these, the ester s of succinic anhydride are particularly important and have numerous applic ations. Therefore, they have attained much attentio n in the last decades and a number of techniques have been proposed to synthesize these compounds. However, the available te chniques for the synthesis of these important compounds have some demerits and need to be addressed properly. In most o f the cases, costly and dangerous chemicals are used as a reactant or c atalyst although such chemicals enhance the hazard chances and environment issues but provide low yield. Therefore , a new technique has been proposed to open the rin g of succinic anhydride using p-toluene sulphonic acid as a catal yst to get monoesters ( 1-29 ) of aryl alcohols. The aryl alcohols used were having electron donating or electron withdrawi ng groups. The prepared monoesters were separated using chromatographic techniques and their structure was confirmed by IR, UV, 1D, 2D, ( 1 H and 13 C) NMR spectra and mass measurements.
Journal of Asian Natural Products Research, Nov 1, 2010
Methanolic extract of Euphorbia cornigera shoots was separated using HPLC, affording compounds 1-... more Methanolic extract of Euphorbia cornigera shoots was separated using HPLC, affording compounds 1-4. Their structures and relative stereochemistry were established after obtaining their spectroscopic (IR, (1)H, (13)C NMR COSY-45°, HOHAHA, HSQC, HMBC, NOESY, and mass measurement) data. On the basis of these data, the compounds were characterized as 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-tetradecanoylingenol (1), 3-O-decanoyl-20-O-hexanoylingenol (2), 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-hexadecanoylingenol (3), and 13-O-dodecanoyl-20-O-hexanoylingenol (4); among these compounds, two (1 and 2) were new metabolites while the rest (3 and 4) were known. The MTT cytotoxicity assay was carried out using amrubicin hydrochloride as a positive control. Compound 1 displayed IC(50) as 5.0 and 2.9 μM against RAW and HT-29 cell lines, respectively, which is 5- and 1.5-folds stronger than the control with IC(50) values of 25 and 4.36 μM, respectively.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Nov 1, 2006
The synthesis and characterization of new coordination compounds of some organotin(IV) chlorides ... more The synthesis and characterization of new coordination compounds of some organotin(IV) chlorides with monomethyl phthalate is reported; the ligand molecules appear to be bound to the tin atom through carbonyl oxygen atoms. Their structures have been characterized by elemental analyses, molar conductance, and bonding in these complexes is discussed in terms of their IR, (1)H, (13)C, (119)Sn NMR and (119 m)Sn Mössbauer spectral studies. The spectroscopic results obtained are in full agreement with the proposed 2:1 stoichiometry. The complexes soluble in DMSO have been screened against a wide spectrum of bacteria and the results obtained are quite promising. The LD(50) values have also been determined in the albino rats. Some of the complexes also exhibit high anti-inflammatory activity.
The industrial and pharmaceutical applications of m onoesters of succinic anhydride have always p... more The industrial and pharmaceutical applications of m onoesters of succinic anhydride have always prompted the scientists for exploring new methods for the synthesis of the prod ucts without using toxic and expensive chemicals. H owever, up to now no significant approach has come forward. The avail able methods are not only ecologically unfriendly i .e. create heat, evolve toxic gases but also provide low yield. Ther efore, a new technique has been proposed in which t he opening of ring of succinic anhydride was performed by treating it with aryl alcohols, using p-toluenesulphonic acid as a catalyst and toluene as a solvent. In this way 1-27 monoesters of di-, and tri-substituted aryl alcoho ls have been synthesised with good yield; however, in case of 2,6-disubstituted alcoho ls the yield was considerably lower than others and was attributed to steric hindrance. The final products were purified using chromatographic techniques and their structur e was confirmed by recording IR, UV, 1D, 2D, ( 1 H- and 13 C-) NMR spectra, mass measurements and elemental analysis.
Industrial, pharmaceutical and daily life applicati ons of esters are countless; among these, the... more Industrial, pharmaceutical and daily life applicati ons of esters are countless; among these, the ester s of succinic anhydride are particularly important and have numerous applic ations. Therefore, they have attained much attentio n in the last decades and a number of techniques have been proposed to synthesize these compounds. However, the available te chniques for the synthesis of these important compounds have some demerits and need to be addressed properly. In most o f the cases, costly and dangerous chemicals are used as a reactant or c atalyst although such chemicals enhance the hazard chances and environment issues but provide low yield. Therefore , a new technique has been proposed to open the rin g of succinic anhydride using p-toluene sulphonic acid as a catal yst to get monoesters ( 1-29 ) of aryl alcohols. The aryl alcohols used were having electron donating or electron withdrawi ng groups. The prepared monoesters were separated using chromatographic techniques and their structure was confirmed by IR, UV, 1D, 2D, ( 1 H and 13 C) NMR spectra and mass measurements.
Journal of Asian Natural Products Research, Nov 1, 2010
Methanolic extract of Euphorbia cornigera shoots was separated using HPLC, affording compounds 1-... more Methanolic extract of Euphorbia cornigera shoots was separated using HPLC, affording compounds 1-4. Their structures and relative stereochemistry were established after obtaining their spectroscopic (IR, (1)H, (13)C NMR COSY-45°, HOHAHA, HSQC, HMBC, NOESY, and mass measurement) data. On the basis of these data, the compounds were characterized as 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-tetradecanoylingenol (1), 3-O-decanoyl-20-O-hexanoylingenol (2), 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-hexadecanoylingenol (3), and 13-O-dodecanoyl-20-O-hexanoylingenol (4); among these compounds, two (1 and 2) were new metabolites while the rest (3 and 4) were known. The MTT cytotoxicity assay was carried out using amrubicin hydrochloride as a positive control. Compound 1 displayed IC(50) as 5.0 and 2.9 μM against RAW and HT-29 cell lines, respectively, which is 5- and 1.5-folds stronger than the control with IC(50) values of 25 and 4.36 μM, respectively.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Nov 1, 2006
The synthesis and characterization of new coordination compounds of some organotin(IV) chlorides ... more The synthesis and characterization of new coordination compounds of some organotin(IV) chlorides with monomethyl phthalate is reported; the ligand molecules appear to be bound to the tin atom through carbonyl oxygen atoms. Their structures have been characterized by elemental analyses, molar conductance, and bonding in these complexes is discussed in terms of their IR, (1)H, (13)C, (119)Sn NMR and (119 m)Sn Mössbauer spectral studies. The spectroscopic results obtained are in full agreement with the proposed 2:1 stoichiometry. The complexes soluble in DMSO have been screened against a wide spectrum of bacteria and the results obtained are quite promising. The LD(50) values have also been determined in the albino rats. Some of the complexes also exhibit high anti-inflammatory activity.
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