Synthesis and evaluation of 3-cyano-4-imino-2-methylthio-4H-pyrido[1,2-a]pyrimidine derivatives as potent antioxidant agents

Anticancer Activity Screening of a Series of Imidazo[2,1‐c][1,2,4]triazolone and Imidazo[1,2 ‐b][1,2,4]triazolone Derivatives Synthesized Under Solvent Free Conditions

“…The reaction of diamino compounds with 2‐[bis(methylthio)methylene]malononitrile was reported to proceed either by elimination of a methyl mercaptane moiety followed by nucleophilic addition and intramolecular cyclization or by elimination of two molecules of methyl meraptane . In this work, it was verified that the reaction proceeded to yield the dihydroimidazo[1,2‐b][1,2,4]triazepine‐7‐carbonitrile 20 via the first postulated mechanism due to the presence of SCH 3 signals in both 1 H NMR and 13 C NMR spectra at δ 2.80 and 19.34, respectively (figure ).…”

Synthesis, crystal structure with free radical scavenging activity and theoretical studies of Schiff bases derived from 1-naphthylamine, 2,6-diisopropylaniline, and substituted benzaldehyde

“…DPPH assay has been used extensively to determine the antioxidant activity of compounds by quantifying their free radical scavenging or hydrogen donor abilities [62]. DPPH has a stable free radical with an odd electron in its structure, and in the presence of antioxidants, the odd electron in DPPH paired up with proton radicals or an electron from antioxidants to form a stable diamagnetic compound [63]. During this process, the purple color of DPPH changed to yellow due to the formation of reduced DPP-H [63].…”

“…DPPH has a stable free radical with an odd electron in its structure, and in the presence of antioxidants, the odd electron in DPPH paired up with proton radicals or an electron from antioxidants to form a stable diamagnetic compound [63]. During this process, the purple color of DPPH changed to yellow due to the formation of reduced DPP-H [63]. The IC50 values were used to evaluate the antioxidant activity of the compounds, and they were calculated from the % DPPH free radical scavenging ability i.e., a low IC50 value is proportional to good antioxidant activity.…”

“…The most reactive radical among the relative oxygen species (ROS) is the hydroxyl radical [63]. In an aqueous solution, it has a half-life less than 1 ns and reacts very close to its site of the formation when produced in vivo [65].…”

Novel Steroidal[17,16-d]pyrimidines Derived from Epiandrosterone and Androsterone: Synthesis, Characterization and Configuration-Activity Relationships

“…Heterocyclic compounds bearing the pyrimidine core are of tremendous interest because the pyrimidine structure, which is an important part of many endogenous substances, can easily interact with enzymes, genetic materials, and bio-components within the cell [ 3 , 4 ]. Up to now, many natural and synthetic pyrimidines derivatives have been of enormous importance and demonstrate a variety of pharmacological activities, including anticancer [ 5 , 6 , 7 , 8 , 9 , 10 , 11 ], antiviral [ 12 , 13 , 14 , 15 ], antifungal [ 16 , 17 , 18 ], antioxidant [ 19 , 20 , 21 , 22 , 23 ], antibacterial [ 24 , 25 , 26 ], antituberculosis [ 27 , 28 ], anticonvulsant [ 29 , 30 , 31 , 32 , 33 , 34 ], antimalarial [ 35 , 36 , 37 , 38 , 39 , 40 ], antihypertensive [ 41 , 42 , 43 , 44 , 45 ], and anti-inflammatory [ 46 , 47 , 48 , 49 , 50 , ...…”