Synthesis and Biological Evaluation of New Phthalazinone Derivatives as Anti-Inflammatory and Anti-Proliferative Agents

Phthalazine Sulfonamide Derivatives as Carbonic Anhydrase Inhibitors. Synthesis, Biological and in silico Evaluation

Carbonic Anhydrases (CAs) are a large family of zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide involved in several biological processes. They show a wide diversity in tissue distribution and their subcellular localization. Twenty-two novel phthalazine derivatives were designed, synthesized, and evaluated against four human isoforms: hCA I, hCA II, hCA IX, and hCA XII. Compounds appeared to be very active mostly against hCA IX (7) and hCA I (6) isoforms being more potent than reference drug acetazolamide (AAZ). Some compounds appeared to be very selective with a selectivity index up to 13.8. Furthermore, docking was performed for some of these compounds on all isoforms to understand the possible interactions with the active site. Additionally, the most active compounds against hCA IX were subjected to cell viability assay. The anticancer activity of the compounds (3 a-d, 5 d, 5 i, and 5 m) was investigated using two human breast cancer cell lines, i. e. MCF-7 and MDA-MB-231 cells, and the normal counterpart, namely MCF10-A cells.

Accessing oxy-functionalized N-heterocycles through rose bengal and TBHP integrated photoredox C(sp3)–O cross-coupling

A C(sp3)–O coupling strategy is described involving tautomerizable N-heterocycles (phthalazinone, pyridne, pyrimidinone and quinoxalinone) carbonyl employing rose bengal as the photocatalyst and TBHP.

Phthalazines and phthalazine hybrids as antimicrobial agents: Synthesis and biological evaluation

Phthalazine and phthalazinone derivatives are important owing to their significant biological activities and pharmacological properties. Herein, a benzoic acid derivative (2), a benzoxazin-1-one derivative (3), and an oxophthalazin-2(1 H)-yl)acetohydrazide (13) are utilized as precursors to construct a novel series of phthalazinones bearing various valuable functional groups in excellent yields via several simple and promising approaches. Finally, the antimicrobial activity of the newly synthesized phthalazines is screened against different microbial strains; namely, Gram-negative and Gram-positive bacteria utilizing Amoxicillin as a standard drug.

Synthesis and Investigation of Phthalazinones as Antitubercular Agents

A series of 2- and 7-substituted phthalazinones was synthesised and their potential as anti-tubercular drugs assessed via Mycobacterium tuberculosis (mc² 6230) growth inhibition assays. All phthalazinones tested showed growth inhibitory activity (MIC <100 μm), and those compounds containing lipophilic and electron-withdrawing groups generally exhibited better anti-tubercular activity. Several lead compounds were identified, including 7-((2-amino-6-(4-fluorophenyl)pyrimidin-4-yl)amino)-2-heptylphthalazin-1(2H)-one (MIC=1.6 μm), 4-tertbutylphthalazin-2(1H)-one (MIC=3 μm), and 7-nitro-phthalazin-1(2H)-one (MIC=3 μm). Mode of action studies indicated that selected pyrimidinyl-phthalazinones may interfere with NADH oxidation, however, the mode of action of the lead compound is independent of this enzyme. MIC=minimum inhibitory concentration.

Recent development of lipoxygenase inhibitors as anti-inflammatory agents

Inflammation is favorable in most cases, because it is a kind of body defensive response to external stimuli; sometimes, inflammation is also harmful, such as attacks on the body's own tissues. It could be that inflammation is a unified process of injury and resistance to injury. Inflammation brings extreme pain to patients, showing symptoms of rubor, swelling, fever, pain and dysfunction. As the specific mechanism is not clear yet, the current anti-inflammatory agents are given priority for relieving suffering of patients. Thus it is emergent to find new anti-inflammatory agents with rapid effect. Lipoxygenase (LOX) is a kind of rate-limiting enzyme in the process of arachidonic acid metabolism into leukotriene (LT) which mediates the occurrence of inflammation. The inhibition of LOX can reduce LT, thereby producing an anti-inflammatory effect. In this review, the LOX inhibitors reported in recent years are summarized, and, in particular, their activities, structure-activity relationships and molecular docking studies are emphasized, which will provide new ideas to design novel LOX inhibitors.