Publications by authors named "Samira Ansari"

5 Publications

  • Page 1 of 1

An Integrated Strategy Reveals Complex Glycosylation of Erythropoietin Using Mass Spectrometry.

J Proteome Res 2021 Jun 10. Epub 2021 Jun 10.

Section Mass Spectrometric Proteomics, Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany.

The characterization of therapeutic glycoproteins is challenging due to the structural heterogeneity of the therapeutic protein glycosylation. This study presents an in-depth analytical strategy for glycosylation of first-generation erythropoietin (epoetin beta), including a developed mass spectrometric workflow for N-glycan analysis, bottom-up mass spectrometric methods for site-specific N-glycosylation, and a LC-MS approach for O-glycan identification. Permethylated N-glycans, peptides, and enriched glycopeptides of erythropoietin were analyzed by nanoLC-MS/MS, and de-N-glycosylated erythropoietin was measured by LC-MS, enabling the qualitative and quantitative analysis of glycosylation and different glycan modifications (e.g., phosphorylation and O-acetylation). The newly developed Python scripts enabled the identification of 140 N-glycan compositions (237 N-glycan structures) from erythropoietin, especially including 8 phosphorylated N-glycan species. The site-specificity of N-glycans was revealed at the glycopeptide level by pGlyco software using different proteases. In total, 114 N-glycan compositions were identified from glycopeptide analysis. Moreover, LC-MS analysis of de-N-glycosylated erythropoietin species identified two O-glycan compositions based on the mass shifts between non-O-glycosylated and O-glycosylated species. Finally, this integrated strategy was proved to realize the in-depth glycosylation analysis of a therapeutic glycoprotein to understand its pharmacological properties and improving the manufacturing processes.
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http://dx.doi.org/10.1021/acs.jproteome.1c00221DOI Listing
June 2021

Recent strategies in the synthesis of thiophene derivatives: highlights from the 2012-2020 literature.

Mol Divers 2020 Jul 30. Epub 2020 Jul 30.

Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, 14176, Iran.

Thiophene-based analogs have been fascinated by a growing number of scientists as a potential class of biologically active compounds. Furthermore, they play a vital role for medicinal chemists to improve advanced compounds with a variety of biological effects. The current review envisioned to highlight some recent and particularly remarkable examples of the synthesis of thiophene derivatives by heterocyclization of various substrates from 2012 on.
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http://dx.doi.org/10.1007/s11030-020-10128-9DOI Listing
July 2020

Vinylazides: versatile synthons and magical precursors for the construction of N-heterocycles.

Mol Divers 2020 May 30. Epub 2020 May 30.

Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.

Nowadays, application of vinylazides as precursors is a key method for the construction of N-heterocycles in organic synthesis. These versatile three-atom synthons can be converted into intermediates such as 2H-azirines, iminyl radicals, iminyl metal complexes, iminyl inions and nitrilium ions that subsequently afford a wide range of polyfunctional cyclic nitrogen-containing compounds. In this review, the reactions of vinylazides leading to these products (in the last decade) are categorized based on the types of the resulting N-heterocyclic rings and a brief and concise description of the reaction mechanisms is presented.
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http://dx.doi.org/10.1007/s11030-020-10106-1DOI Listing
May 2020

Synthesis and pharmacological properties of polysubstituted 2-amino-4H-pyran-3-carbonitrile derivatives.

Mol Divers 2020 Nov 25;24(4):1385-1431. Epub 2019 Sep 25.

Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.

2-Amino-3-cyano-4H-chromenes are structural core motifs that received increasing attention in the last years due to their interesting potential pharmacological properties. In this review, the synthetic methods for these compounds are classified based on the type of catalyst in the pertinent reactions. In addition, the wide range of pharmacological properties of these compounds is covered in a separate section.
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http://dx.doi.org/10.1007/s11030-019-09994-9DOI Listing
November 2020

The use of magnetic starch as a support for an ionic liquid-β-cyclodextrin based catalyst for the synthesis of imidazothiadiazolamine derivatives.

Int J Biol Macromol 2019 Aug 28;135:453-461. Epub 2019 May 28.

Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran 14176, Iran. Electronic address:

In this paper, a novel catalyst is introduced based on the introduction of an ionic liquid onto the β-cyclodextrin. The ionic liquid-β-cyclodextrin was anchored to magnetic starch (denoted β[email protected]) and fully characterized by several methods including TEM, TGA, VSM and FT-IR. The catalyst was used for the synthesis of imidazo[2,1-b][1,3,4]thiadiazol-5-amine and imidazo[1,2-a]pyridin-3-amine derivatives. β[email protected] catalyst showed very good activity in the synthesis of diphenylimidazo[2,1-b][1,3,4]thiadiazol-5-amine derivatives from the corresponding benzaldehyde, semicarbazide, benzaldehydes and isocyanides. The products were obtained in a mild reaction conditions in good isolated yields in the presence of β[email protected] as catalyst. The catalyst showed to be magnetically reusable, and gave very good results in 10 sequential reactions.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.05.197DOI Listing
August 2019