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Issa Yavari Rahimeh Hajinasiri S. Zahra Sayyed-Alangi Nasir Iravani 《Monatshefte für Chemie / Chemical Monthly》2008,139(9):1029-1031
An efficient synthesis of ethyl 3-alkyl-4-oxo-2-thioxo-1,3-thiazolane-5-carboxylates via reaction of primary amines with CS2 in the presence of diethyl 2-chloromalonate is described.
Correspondence: Issa Yavari, Chemistry Department, Tarbiat Modares University, PO Box 14115-175, Tehran, Iran. 相似文献
106.
Mohammad Nasir Uddin Victoria F. Samanidou Ioannis N. Papadoyannis 《Journal of separation science》2008,31(21):3704-3717
A simple, sensitive, selective, and reproducible RP‐HPLC method with DAD detection at 240 nm was developed for the determination of six 1,4‐benzodiazepines: bromazepam (BRZ), clonazepam (CLZ), diazepam (DZP), flunitrazepam (FNZ), lorazepam (LRZ), alprazolam (APZ); and two metabolites: α‐hydroxyalprazolam (HALZ) and α‐hydroxytriazolam (HTZL) in human plasma, urine, and saliva, using colchicine as internal standard, after SPE using Nexus Varian cartridges. Separation was performed on a Kromasil C8 (250 mm×5 mm, 5 μm) analytical column with a gradient mobile phase containing methanol, ACN and 0.05 M ammonium acetate. Linearity was held within the range 0.3–20.0 ng/μL, with coefficients of determination (r2) better than 0.997. The within‐ and between‐day assay RSD at 2, 4, 8 ng/μL ranged from 0.03 to 4.7% and 0.5 to 7.0%, respectively in standards, from 1.3 to 7.9% and 3.3 to 7.3%, respectively in plasma, from 2.1 to 6.0% and 2.1 to 7.8%, respectively in urine and at 0.5, 1.0, 2.0 ng/μL ranged from 2.22 to 5.8% and 2.2 to 8.1%, respectively, in saliva. The mean relative recoveries were 96.3–108.6, 96.0–108.2, 94.3–107.1, 97.0–107.0% in within‐day assay and 96.8–107.7, 94.6–107.6, 93.2–105.8, 96.0–108.6 in between‐day assay for standard, plasma, urine, and saliva, respectively. The LOD and LOQ were 0.02–0.47 and 0.07–1.57 ng/μL, respectively. 相似文献
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Perwez Alam Nasir Ali Siddiqui Md. Tabish Rehman Afzal Hussain Ali Akhtar Showkat R. Mir Mohamed Fahad Alajmi 《Molecules (Basel, Switzerland)》2021,26(7)
Parthenolide, a strong cytotoxic compound found in different parts of Tarchonanthus camphoratus which motivated the authors to develop an optimized microwave-assisted extraction (MEA) method using Box–Behnken design (BBD) for efficient extraction of parthenolide from the stem of T. camphoratus and its validation by high-performance thin-layer chromatography (HPTLC) and cytotoxic analysis. The optimized parameters for microwave extraction were determined as: 51.5 °C extraction temperature, 50.8 min extraction time, and 211 W microwave power. A quadratic polynomial model was found the most suitable model with R2 of 0.9989 and coefficient of variation (CV) of 0.2898%. The high values of adjusted R2 (0.9974), predicted R2 (0.9945), and signal-to-noise ratio (74.23) indicated a good correlation and adequate signal, respectively. HPTLC analyzed the parthenolide (Rf = 0.16) content in T. camphoratus methanol extract (TCME) at λmax = 575 nm and found it as 0.9273% ± 0.0487% w/w, which was a higher than expected yield (0.9157% w/w). The TCME exhibited good cytotoxicity against HepG2 and MCF-7 cell lines (IC50 = 30.87 and 35.41 µg/mL, respectively), which further supported our findings of high parthenolide content in TCME. This optimized MAE method can be further applied to efficiently extract parthenolide from marketed herbal supplements containing different Tarconanthus species. 相似文献
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Md. Asraful Alam Roberto Parra-Saldivar Muhammad Bilal Chowdhury Alfi Afroze Md. Nasir Ahmed Hafiz M.N. Iqbal Jingliang Xu 《Molecules (Basel, Switzerland)》2021,26(8)
The recently emerged COVID-19 disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has adversely affected the whole world. As a significant public health threat, it has spread worldwide. Scientists and global health experts are collaborating to find and execute speedy diagnostics, robust and highly effective vaccines, and therapeutic techniques to tackle COVID-19. The ocean is an immense source of biologically active molecules and/or compounds with antiviral-associated biopharmaceutical and immunostimulatory attributes. Some specific algae-derived molecules can be used to produce antibodies and vaccines to treat the COVID-19 disease. Algae have successfully synthesized several metabolites as natural defense compounds that enable them to survive under extreme environments. Several algae-derived bioactive molecules and/or compounds can be used against many diseases, including microbial and viral infections. Moreover, some algae species can also improve immunity and suppress human viral activity. Therefore, they may be recommended for use as a preventive remedy against COVID-19. Considering the above critiques and unique attributes, herein, we aimed to systematically assess algae-derived, biologically active molecules that could be used against this disease by looking at their natural sources, mechanisms of action, and prior pharmacological uses. This review also serves as a starting point for this research area to accelerate the establishment of anti-SARS-CoV-2 bioproducts. 相似文献
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Nisar Jan Nasir Umar Ali Ghulam Shah Afzal Farooqi Zahoor Hussain Iqbal Munawar Shah Muhammad Raza 《Cellulose (London, England)》2021,28(12):7593-7607
Cellulose - In this work we have attempted to use biomass as energy source which is abundantly available throughout the world. The work is focused on pyrolysis of sugarcane bagasse in a... 相似文献
110.
In this article, we report the synthesis of two (A3 and A4) new ferrocene-based heterobimetallic compounds of Fe and Sn. Both compounds are structural isomers with formula (C5H5)Fe(C5H4C6H4COO)Sn(CH3)3 and have been characterized by elemental analysis, cyclic voltammetry, FTIR, UV–Vis and NMR spectroscopy. Additionally, the structure of A3 was confirmed by single-crystal XRD studies. XRD studies confirmed that in the solid phase A3 exists as a unidirectional polymeric material. DNA-binding potential of these compounds was evaluated by UV–Vis spectroscopy, cyclic voltammetry, and viscosity measurements. These interaction assays conclude that A3 (binding constant ~104 M?1) and A4 have good attraction toward DNA and bind with DNA in intercalative manner. 相似文献