1,720,998 research outputs found
Crystal structure of 1-{4-hydroxy-3-[(pyrrolidin-1-yl)methyl]phenyl}-3-phenylprop-2-en-1-one
Full text linkIn the title compound, C20H21NO2, the pyrrolidine ring adopts an envelope conformation with the N atom at the flap position. The central benzene ring makes dihedral angles of 21.39 (10) and 80.10 (15)° with the phenyl ring and the mean plane of the pyrrolidine ring, respectively. The molecular conformation is stabilized by an intramolecular O—H...N hydrogen bond, which closes an S(6) ring. A weak C—H...π interaction is observed in the crystal
Syntheses and stability studies of some Mannich bases of acetophenones and evaluation of their cytotoxicity against Jurkat cells.
No full textAntimicrobial evaluation of some Mannich bases of acetophenones and representative quaternary derivatives.
No full textCytotoxic activities of some mono and bis Mannich bases derived from acetophenone in brine shrimp bioassay.
No full textAntifungal evaluation of bis Mannich bases derived from acetophenones and their corresponding piperidinols and stability studies.
No full textExploring the Structure-Activity Relationship of COX Inhibitors with Anticancer Effects: A Comprehensive Review
No full textCancer is a multifaceted disease with high mortality rates, and current treatments face challenges such as chemoresistance and tumor adaptation. Since Virchow reported the first case of cancer-related chronic inflammation, numerous clinical and epidemiological studies have indicated that around 15-20% of malignant tumors are caused by inflammation. Cyclooxygenase-2 (COX-2), which is the key enzyme in inflammation, has been implicated in tumorigenesis through various mechanisms, including promoting angiogenesis, inhibiting apoptosis, and enhancing the invasiveness of cancer cells. Moreover, COX inhibitors have demonstrated a substantial reduction in death rates associated with esophageal and colon cancer. In this context, targeting COX-2 is an effective strategy for cancer prevention and treatment.This review focuses on the analysis of studies conducted between 2014 and 2024, which evaluate the structure-activity relationship of molecules intended to exhibit cytotoxic activity through COX inhibition. The studies followed both classical and non-classical COX-2 selective drug design strategies. While some focused on the classical approach, utilizing diaryl heterocyclic structures, others explored non-classical designs with a cyclic central scaffold and a linear core. Additionally, several manuscripts employed well-known COX inhibitors, including licofelone, indomethacin, naproxen, tolfenamate, celecoxib, flumizole, and ketoprofen, as starting points for further derivatization and optimization. Cytotoxic activity was evaluated using various cell lines, including MCF-7, HCT-116, and A549, through assays such as MTT, CellTiter, and MTS. Additionally, studies examined the relationship between COX-2 inhibition and key cancer pathways, including apoptosis and the involvement of enzymes like HDAC, EGFR, and topoisomerase.The majority of studies reported promising cytotoxic activity in COX-2 selective inhibitors. Compounds synthesized with diphenyl heterocyclic scaffolds exhibited enhanced COX-2 selectivity and anticancer efficacy. In particular, derivatives in studies 9, 16, and 24 demonstrated significant activity comparable to standard drugs like celecoxib and doxorubicin. However, only a few studies indicated a weak correlation between COX-2 inhibition and cytotoxicity, suggesting the need for further investigation into other cancer-related mechanisms.This review highlights the potential of COX-2 selective inhibitors in anticancer drug development. The findings support the development of selective COX-2 inhibitors with diverse chemical structures as a promising strategy for cancer therapy
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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