A5055322781- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Synthesis and Biological Evaluation
- Quinazolinone synthesis and applications
- Synthesis and Characterization of Heterocyclic Compounds
- Synthesis of heterocyclic compounds
- Catalytic C–H Functionalization Methods
- Crystallography and molecular interactions
- Multicomponent Synthesis of Heterocycles
- Radical Photochemical Reactions
- Oxidative Organic Chemistry Reactions
- Phenothiazines and Benzothiazines Synthesis and Activities
- Bioactive Compounds and Antitumor Agents
- Synthesis and Reactivity of Sulfur-Containing Compounds
- Synthesis and Reactivity of Heterocycles
- Synthesis of β-Lactam Compounds
- Synthetic Organic Chemistry Methods
- Erythrocyte Function and Pathophysiology
- Chemical synthesis and alkaloids
- Carbohydrate Chemistry and Synthesis
- Hemoglobinopathies and Related Disorders
- Chemical Reactions and Mechanisms
- Cancer therapeutics and mechanisms
- Phosphorus compounds and reactions
- Fluorine in Organic Chemistry
Ollscoil na Gaillimhe – University of Galway
2018-2022
University of Cyprus
2010-2019
Reacting N-aryliminophosphoranes with 1-(het)aroyl-2-aryldiazenes in preheated diphenyl ether at ca. 150-250 °C for 5-25 min affords most cases the 1,3-diaryl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yls (aka Blatter radicals) moderate to good yields. All new compounds are fully characterized, including EPR and CV studies radicals. Single-crystal X-ray structures of 1-benzoyl-2-(perfluorophenyl)diazene 1-(perfluorophenyl)-3-phenyl-1,4-dihydrobenzo[e][1,2,4]triazinyl also presented.
1,3-Diphenylbenzo[e][1,2,4]triazin-7(1H)-one, the oxidation product of 1,3-diphenyl-1,4-dihydro-1,2,4-benzotriazin-4-yl (Blatter's radical), reacts with N′-arylbenzamidines in PhMe at ca. 100 °C presence N,N-diisopropylethylamine (Hünig's base) (1 equiv.) to give N′-aryl-N-(1,7-dihydro-7-oxo-1,3-diphenylbenzo[e][1,2,4]triazin-6-yl)benzimidamides 49–95% yield. In neat AcOH heated 120 °C, N′–aryl-N-(1,7-dihydro-7-oxo-1,3-diphenylbenzo[e][1,2,4]triazin-6-yl)benzimidamides cyclodehydrate novel...
Benzo[4,5]imidazo[1,2-c]quinazoline-6-carbonitriles are prepared in high yields via three new routes: (1) a Cu(OTf)2 (0-5 mol %) catalyzed hypervalent iodine [PhI(OTf)2] mediated oxidative coupling of 4-anilinoquinazoline-2-carbonitriles neat trifluoroacetic acid (TFA); (2) Pd(OAc)2 (10 or CuI nonoxidative 4-(2-bromoanilino)quinazoline-2-carbonitrile; and (3) Pd(Ar3P)3 [Ar = 3,5-(F3C)2C6H3] [aka Superstable Pd(0) Catalyst] intramolecular C-N cyclization...
2-Amino-N′-arylbenzamidines react with 4,5-dichloro-1,2,3-dithiazolium chloride (Appel salt) in the presence of Hünig's base (2 equiv) to give one step 3-aryl-4-imino-3,4-dihydroquinazoline-2-carbonitriles 53–81% yields. Nine examples are presented along single-crystal X-ray structure 4-imino-3-phenyl-3,4-dihydroquinazoline-2-carbonitrile. Furthermore, behavior latter toward both acid and hydrolysis is investigated. All new compounds fully characterized, a mechanistic rationale for formation...
The optimization of a multicomponent reaction, to prepare triarylpyridines (triphenylpyridine), and which includes 17 examples where each aryl substituent is distinct (non-symmetric pyridine) reported. non-symmetric triarylpyridine aqrar forming reaction involves the sequential addition two different acetophenones benzylamine in DMF presence copper (I) iodide (20 mol %), methanolic ammonia (2 equiv.), oxygen. optimized method was used give twenty five 43–91% yield, including products with...
Cell viability studies for benzo[1,2,4]triazin-7-ones and 1,2,4-benzotriazinyl (Blatter-type) radical precursors are described with comparisons made 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO). All of the stable free radicals were several orders magnitude less cytotoxic than benzo[1,2,4]triazin-7-ones. The synthesis evaluation two new pyrid-2-yl described, where altering 1,3-substitution from phenyl to increased cytotoxicity against most cancer cell lines, as indicated using National Cancer...
The reactivity of hydrogen peroxide and catalytic hydroiodic acid toward 3,6-dimethoxy-2-(cycloamino)anilines is tunable to give ring-fused benzimidazoles or 1,4,6,9-tetramethoxyphenazine in high yield. Mechanisms via a detected nitroso-intermediate are proposed for oxidative cyclization the unexpected intermolecular displacement oxazine. An aqueous solution molecular iodine capable same transformations. Oxidative demethylation gave targeted benzimidazolequinones, including without cleavage...
7-Oxo-1,2,4-benzotriazines (benzo[1,2,4]triazin-7-ones) are reversible thioredoxin reductase inhibitors that exhibit very strong correlations to pleurotin. In this article, we provide the first synthesis of fluorinated derivatives. Fluorination using Selectfluor benzo[1,2,4]triazin-7-ones occurs regioselectively and in high yield at enamine-activated position. This electron N-lone pair activation overrides activation/deactivation effects some other substituents. The reaction time was...
Eight 2-phenyl-3H-imidazo[4,5-b]quinoline-9-carbonitriles 15 are prepared in four steps from N′-arylbenzamidines 11 and tetracyanoethylene (TCNE) ∼70–90% yields. The transformation involves the initial formation of N-aryl-N′-(1,2,2-tricyanovinyl)benzamidines 12 87–99% yields, which MeCN undergo a 5-exodig cyclization to give 2-[1-aryl-5-imino-2-phenyl-1H-imidazol-4(5H)-ylidene]malononitriles 13 84–92% while MeOH (Z)-2-[2-phenyl-4-(arylimino)-1H-imidazol-5(4H)-ylidene]malononitriles 14 formed...
The traditional thermal Mannich reaction is unsuitable for preparing polymerizable N-methylene amino substituted acrylamides and methacrylamides. Herein we provide a facile multi-gram high yield synthesis of these monomeric precursors to stimuli-responsive polymers by the addition methacrylamides onto in situ generated or freshly isolated methylene Schiff base (iminium) salts. X-ray crystal structure hydrated iminium salt, 1-(hydroxymethyl)azocan-1-ium chloride monomer·HCl salt...
β-Thalassemia (β-thal) is a hemoglobinopathy characterized by reduced or absent β-globin production. Pharmacological reactivation of the γ-globin gene for production fetal hemoglobin (Hb F) presents an attractive treatment strategy. In effort to identify promising therapeutic agents, we evaluated 80 analogues histone deacetylase inhibitor MS-275, known Hb F inducer. The chemical were identified via molecular modeling and targeted modifications. Nine novel agents exhibited significant...
Abstract A two‐step synthesis of title radicals (IV) is elaborated using a base‐promoted reaction benzotriazinone (I) with benzamidines (II) followed by cyclization resulting benzimidamides (III) in acetic acid.
Abstract The reaction of 2‐amino‐N‐arylbenzamidines with tetracyanoethene is investigated under different conditions to provide either imidazoline type (III), quinazolines (IV) or (V) as sole main products.