Publications by authors named "Maia Merlani"

Here, we report on the synthesis and biological evaluation of a novel peptide-drug conjugate, P6-SN38, which consists of the EGFR-specific short cyclic peptide, P6, and the Topo I inhibitor SN38, which is a bioactive metabolite of the anticancer drug irinotecan. SN38 is attached to the peptide at position 20 of the E ring's tertiary hydroxyl group via a mono-succinate linker. The developed peptide-drug conjugate (PDC) exhibited sub-micromolar anticancer activity on EGFR-positive (EGFR+) cell lines but no effect on EGFR-negative (EGFR-) cells.

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This study reports the antimicrobial activities of the biopolymers poly[3-(3,4-dihydoxyphenyl)glyceric acid] (PDHPGA) and poly[2-methoxycarbonyl-3-(3,4-dihydroxyphenyl)oxirane] (PMDHPO), extracted from the six plants of Boraginaceae family: (), (), and (), (), (), and () collected in various parts of Georgia. The study revealed that the antibacterial activities were moderate, and biopolymers from only three plants showed activities against all tested bacteria. Biopolymers from stems as well as and did not show any activity except low activity against a resistant strain, which was the most resistant among all three resistant strains.

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Twelve steroid based hydrazones were in silico evaluated using computer program PASS as antimicrobial agents. The experimental evaluation revealed that all compounds have low to moderate antibacterial activity against all bacteria tested, except for with MIC at a range of 0.37-3.

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This study reports the first enzymatic synthesis leading to several oligomer analogues of poly[3-(3,4-dihydroxyphenyl)glyceric acid]. This biopolymer, extracted from plants of the Boraginaceae family has shown a wide spectrum of pharmacological properties, including antimicrobial activity. Enzymatic ring opening polymerization of 2-methoxycarbonyl-3-(3,4-dibenzyloxyphenyl)oxirane (MDBPO) using lipase from leads to formation of poly[2-methoxycarbonyl-3-(3,4-dibenzyloxyphenyl)oxirane] (PMDBPO), with a degree of polymerization up to 5.

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We evaluated the antimicrobial activity of thirty-one nitrogen-containing 5-alpha-androstane derivatives in silico using computer program PASS (Prediction of Activity Spectra for Substances) and freely available PASS-based web applications (www.way2drug.com).

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Fourteen steroid compounds were in silico evaluated using computer program PASS as antimicrobial agents. The experimental studies evaluation revealed that all compounds have good antibacterial activity with MIC at range of 0.003-0.

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Background: Phenolic acids (caffeic-, ferulic and p-coumaric acid) are widely distributed in the plant kingdom and exhibit broad spectrum of biological activities, including antimicrobial activity.

Objective: The goal of this paper is the synthesis of some caffeic acid derivatives selected based on computer-aided predictions and evaluate their in vitro antimicrobial properties against Gram positive and Gram negative bacteria and also a series of fungi.

Methods: In silico prediction of biological activity was used to identify the most promising structures for synthesis and biological testing, and the putative mechanisms of their antimicrobial action.

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Caffeic acid-derived polyethers are a class of natural products isolated from the root extracts of comfrey and bugloss, which are endowed with intriguing pharmacological properties as anticancer agents. The synthesis of new polyether derivatives is achieved through ring-opening polymerization of chiral 2,3-disubstituted oxiranes, whose absolute configurations define the overall stereochemistry of the produced polymer. The absolute stereochemistry of one of these building blocks, methyl trans-3-(3,4-dimethoxy-phenyl)glycidate (3), was therefore characterized by the combination of enantioselective high-performance liquid chromatography (HPLC), electronic circular dichroism (ECD) spectroscopy, and time-dependent density functional theory (TD-DFT) calculations.

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The major obstacles in human prostate cancer (PCA) treatment are the development of resistance to androgen ablation therapy leading to hormone-refractory state and the toxicity associated with chemotherapeutic drugs. Thus, the identification of additional non-toxic agents that are effective against both androgen-dependent and androgen-independent PCA is needed. In the present study, we investigated the efficacy of a novel phytochemical poly[3-(3, 4-dihydroxyphenyl)glyceric acid] (p-DGA) from Caucasian species of comfrey (Symphytum caucasicum) and its synthetic derivative syn-2, 3-dihydroxy-3-(3, 4-dihydroxyphenyl) propionic acid (m-DGA) against PCA LNCaP and 22Rv1 cells.

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Elucidation of the main structural unit of a water-soluble, high-molecular weight preparation from the crude polysaccharides of Anchusa italica Retz. roots has been carried out. According to 13C NMR, 1H NMR and 2D heteronuclear 1H/13C HSQC spectral data, the main structural element of the high-molecular, water-soluble preparation was a regularly substituted polyoxyethylene chain, namely poly[oxy-1-carboxy-2-(3,4-dihydroxyphenyl)ethylene].

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The racemic and enantioselective synthesis of a novel glyceric acid derivative, namely, 2,3-dihydroxy-3-(3,4-dihydroxyphenyl)-propionic acid as well as the antioxidant activities is described. The virtually pure enantiomers, (+)-(2R,3S)-2,3-dihydroxy-3-(3,4-dihydroxyphenyl)-propionic acid and (-)-(2S,3R)-2,3-dihydroxy-3-(3,4-dihydroxyphenyl)-propionic acid were synthesized for the first time via Sharpless asymmetric dihydroxylation of trans-caffeic acid derivatives using the enantiocomplementary catalysts, (DHQD)(2)-PHAL and (DHQ)(2)-PHAL. The determination of enantiomeric purity of the novel chiral glyceric acid derivatives was performed by high-performance liquid chromatographic techniques on the stage of their alkylated precursors.

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