International Journal of Chemical and Analytical Science最新文献

Aim

The extreme efforts have been developed to design novel compounds to strains of resistant micro-organisms. On-going search for novel and amazing drug delivery systems is primarily impact of the well-established fact that the convectional dosages are not sufficiently effective in conveying the drug compounds to its site of action and this has required the need to search for more efficient drugs. The metal complexes of Co (II), Ni (II) and Cu (II) with a tridentate ligand 2, 5-diamino-1, 3, 4-thiadiazole has been prepared by cyclisation of bithiourea in a 3% hydrogen peroxide medium. 2, 5-diamino-1, 3, 4-thiadiazole acts as neutral tridentate ligand and coordinates through the sulphur atom and nitrogen of the amines. The complexes are non-electrolyte in DMF. The complexes exhibited octahedral geometry. The antimicrobial activities of ligand and its complexes were screened using sensitivity test, minimum inhibition concentration and minimum bacterial concentration method. Metal chelates showed greater antimicrobial activities as compared to the control and the ligand. The metal chelates and the ligand did not exhibited activity against Aspergillus niger and Penicillin species.

Methods

Elemental analyses, IR spectra, magnetic susceptibilities by using Faraday Balance, molar conductance by using Genway 4200 conductivity meter. Metal estimation by using Alpha 4 Atomic Absorption Spectrophotometer. Thin layer chromatography was carried out using TLC plate coated with silica gel.

Results

The results of the elemental analyses are in good agreement with those calculated for the suggested formulae, 1:2 (M:L) solid chelates are isolated and found to have the general formulae [(ML2)] X2; M=Co (II), Ni (II) and Cu (II) (X=Cl). The IR spectra revealed that the ligand L is a neutral tridentate ligand. It coordinated to the metal ions via the nitrogen of the amines and sulphur atom. The molar conductance values of the Co (II), Ni (II), and Cu (II) complexes were relatively low, indicating the non-electrolytic nature of these complexes. The ligand and metal complexes show antimicrobial effect against the tested organism species except against molds of penicillin and Aspergillus. Niesseria gonorrhoea was probably the most sensitive organism to the 2, 5-Diamino-1, 3, 4-Thiadizole and its metal complexes. Metal complexes showed greater activity against some of the micro-organisms compared to the parent compounds.

Conclusion

In this paper we conclude from combined results of the chemical and physical analysis that the ligand (2, 5-diamino-1, 3, 4-thiadiazole) coordinated with Cu, Co and Ni. The metal complexes possess better physical properties than the parent compound. Metal complex of 2,5-diamino-1,3,4-thiadiazole would be a better therapeutic drug for antibacterial treatment.

In the present paper we have reported a simple and convenient titrimetric method for determination of non-steroidal anti-inflammatory drugs (NSAIDs) e.g. aceclofenac, diclofenac sodium, ibuprofen, mefenamic acid and nimesulide in pure form and in their pharmaceutical preparations such as acecloren (Tab), aclofen (Tab), voveran (Tab), diclomax (Inj), brufen (Tab), norswell (Tab), meftal (Tab), mef-T (Tab), nicip-DT (Tab) and dolamide (Tab) with ammonium hexanitratocerate (AHC) reagent. It is a versatile oxidizing agent of cerium (IV) and is being widely used as an oxidant for several classes of organic compounds. During estimation it was noted that the excipients present in pharmaceutical preparations do not interfere. The value of percentage error, coefficient of variation (CV) and standard deviation (SD) prove the method to be precise and reproducible. To establish authenticity of the method, recovery experiments were also carried out by standard drug addition method.

Background/aim

In the present study, a series of novel phthalimide derivatives synthesized because of its potent antimicrobial and antimycobacterial activity.

Method

Structurally modified phthalimide derivatives were prepared through condensation of substituted phthalic anhydride with corresponding acetazolamide, cycloserine and isoniazid with variable yields. Synthesized Compounds (6a–d), (7a–d) and (8a–d) analyzed for their structures, in vitro antimicrobial and antimycobacterial activity.

Result

Among the synthesized compounds, compound 6b, 7b and 8b was found to be the most potent against Gram-positive bacteria Bacillus subtilis, Gram-negative bacteria Escherichia coli, Mycobacterium tuberculosis CIP and M. tuberculosis H37Rv.

Conclusion

A series of novel phthalimide derivatives of biological interest were synthesized and analyzed, suggests that it an interesting compound compared to the current therapeutic agents and are considered to investigate further for the same.

Background

Chemical diversity of endophytic fungi has made them an alternate source for bioactive compounds. Novel biotopes with promising bioactivity are expected from endophytes of medicinal plants from biodiversity hotspots. Therefore, endophytes of Nothapodytes foetida and Hypericum mysorense from Western Ghats, India were screened for free radical scavenging activity and anti-radical metabolites were profiled.

Methods

Endophytes were isolated from surface sterilized leaves, stems and barks of N. foetida and H. mysorense. Ethyl acetate extracts of culture filtrates were tested for antiradical activity using DPPH and ABTS free radicals. Antiradical spots on developed chromatogram were profiled by spraying with DPPH solution.

Results

A dose dependent antiradical activity of variable magnitude was observed. Fourteen isolates from H. mysorense and thirteen isolates from N. foetida showed significant antiradical activity. 55% of tested isolates exhibited more than 95% quenching of DPPH radicals and 40% recorded more than 75% scavenging activity. A total of 66.67% of the tested isolates recorded more than 95% scavenging of ABTS radicals and 29.6% showed more than 75% scavenging activity. TLC of active extracts showed the presence of a minimum three and maximum thirteen radical scavenging metabolite spots.

Conclusion

This is the first report on antiradical activity of endophytic isolates of H. mysorense. Active metabolite profiling would help in the further purification of most potent and abundant bioactive molecule from the fungal endophytic extracts. Further purification and characterization of the active metabolites may lead to the discovery of novel bioactive molecules of industrial and pharmaceutical importance.

Aim

The aim of the present work was to develop a novel, reliable and accurate Liquid Chromatography–Mass Spectrometry/Mass spectrometry (LC–MS/MS) method for the estimation of a potent 5-HT1B/1D receptor agonist, Rizatriptan in human plasma and to validate the proposed method.

Experimental

Zolmitriptan was used as the internal standard. The analyte and internal standard were isolated from 100 mL plasma samples by liquid-liquid extraction (LLE) and chromatographed on an ACE C18 column, (150 × 4.6 mm, 3 μm) with a mobile phase consisting of acetonitrilee10 mM aqueous ammonium acetate-acetic acid (90:10:0.5% v/v/v) pumped at 1.0 mL/min. The method had a chromatographic total run time of 10 min. A Varian 1200 L electrospray tandem mass spectrometer equipped with an electrospray ionization source was operated in multiple reaction monitoring (MRM) mode with the precursor-to-product ion transitions m/z 270.39/201.3 (Rizatriptan) and 288.43/182.2 (Zolmitriptan) used for quantitation.

Results and discussion

The method was validated over the concentration range of 50–1000 ng/ml and was found to have acceptable accuracy, precision, linearity, and selectivity. The mean extraction recovery from spiked plasma samples was above 98.26–101.32%. The intra-day accuracy of the assay ranged from 99.525 to 103.32% and intra-day precision ranged from 99.525 to 103.32% C.V. Inter-day accuracy and precision results for quality control samples ranged between 103.62 and 105.196% of nominal and precision is observed to be 5.45–10.946% C.V. The drug was found to be stable after a number of stability studies.

Conclusion

According to the validated results, the proposed method was found to be specific, accurate, and precise and could be used for the estimation of Rizatriptan in human plasma over a concentration range of 50.0–1000 ng/ml and can be applied for the routine analysis.

Context

Micellar thin layer chromatography (MLC) used for separation of various heavy metal ions from various environmental samples. MLC successfully applied for semiquanitative and spectrometry identification of metal ions.

Objective

Utilization of MLC in separation, semiquanitative determination and Chromatospectrometric method for estimation of ${\text{UO}}_2^{2+}$ on bismuth silicate layer, using Tween-80.

Method

Ascending development of the plates performed with aq. micellar, hydro-organic and water-organic-surfactant as mobile phase. Separation carried out on thin layer of bismuth silicate and layer developed with non-ionic surfactant Tween-80.

Results and conclusions

Acetone was found to be most effective additive at 10% concentration with 5% Tween-80. This method successfully applied to identification and separation of Cd₂, Hg₂ and Co₂ from river water and industrial wastewater. Semiquantitative as well as spectrometry techniques was used for quantitative analysis of ${\text{UO}}_2^{2+}$ in river water with preliminary separation from Fe₃ and Cu₂. Maximal recovery of 90% observed. This TLC method is rapid, with development times averaging 2–5 min.