Vasorelaxing properties of some phenylacridine type potassium channel openers in isolated rabbit thoracic arteries

Dendrons containing boric acid and 1,3,5-tris(2-hydroxyethyl)isocyanurate covalently attached to silica-coated magnetite for the expeditious synthesis of Hantzsch esters

A new multifunctional dendritic nanocatalyst containing boric acid and 1,3,5-tris(2-hydroxyethyl)isocyanurate covalently attached to core-shell silica-coated magnetite (Fe3O4@SiO2@PTS-THEIC-(CH2)3OB(OH)2) was designed and properly characterized by different spectroscopic or microscopic methods as well as analytical techniques used for mesoporous materials. It was found that the combination of both aromatic π-π stacking and boron-oxygen ligand interactions affords supramolecular arrays of dendrons. Furthermore, the use of boric acid makes this dendritic catalyst a good choice, from corrosion, recyclability and cost points of view. The catalytic activity of Fe3O4@SiO2@PTS-THEIC-(CH2)3OB(OH)2, as an efficient magnetically recoverable catalyst, was investigated for the synthesis of polyhydroacridines (PHAs) as well as polyhydroquinolines (PHQs) via one-pot multicomponent reactions of dimedone and/or ethyl acetoacetate, different aldehydes and ammonium acetate in EtOH under reflux conditions. Very low loading of the catalyst, high to quantitative yields of the desired PHAs or PHQs products, short reaction times, wide scope of the substrates, eliminating any toxic heavy metals or corrosive reagents for the modification of the catalyst, and simple work-up procedure are remarkable advantages of this green protocol. An additional advantage of this magnetic nanoparticles catalyst is its ability to be separated and recycled easily from the reaction mixture with minimal efforts in six subsequent runs without significant loss of its catalytic activity. This magnetic and dendritic catalyst can be extended to new two- and three-dimensional covalent organic frameworks with different applications.

A facile and efficient synthesis of 1,8-dioxodecahydroacridines derivatives catalyzed by cobalt-alanine metal complex under aqueous ethanol media

A facile and convenient method for the synthesis of acridines and its derivatives was developed through one-pot, three-component condensation reaction of aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione, aryl amines or ammonium acetates in the presence of a catalytic amount of cobalt–alanine metal complex using aqueous ethanol as a reaction medium is reported. The present described novel methodology offers several advantages over the traditional methods reported in the literature, such as mild reaction conditions, inexpensive catalyst, short reaction times, excellent yields of products, simplicity and easy workup are the advantages of this procedure.

N-Propyl benzoguanamine sulfonic acid supported on magnetic Fe3O4 nanoparticles: a novel and efficient magnetically heterogeneous catalyst for the synthesis of 1,8-dioxo-decahydroacridine derivatives

An MNPs-N-propyl-benzoguanamine-SO₃H nanocatalyst as a novel, retrievable, economic and heterogeneous catalyst is prepared for the synthesis of 1,8-dioxo-decahydroacridine derivatives.

Covalently anchored sulfamic acid on cellulose as heterogeneous solid acid catalyst for the synthesis of structurally symmetrical and unsymmetrical 1,4-dihydropyridine derivatives

A novel heterogeneous solid acid catalyst has been prepared by covalent grafting of chlorosulphonic acid on amino-functionalized cellulose (Cell–Pr-NHSO₃H).

Microwave assisted synthesis of novel acridine-acetazolamide conjugates and investigation of their inhibition effects on human carbonic anhydrase isoforms hCA I, II, IV and VII

4-Amino-N-(5-sulfamoyl-1,3,4-thiadiazol-2-yl)benzamide was condensed with cyclic-1,3-diketones (dimedone and cyclohexane-1,3-dione) and aromatic aldehydes under microwave irradiation, leading to a series of acridine-acetazolamide conjugates. The new compounds were investigated as inhibitors of carbonic anhydrases (CA, EC 4.2.1.1), and more precisely cytosolic isoforms hCA I, II, VII and membrane-bound one hCA IV. All investigated isoforms were inhibited in low micromolar and nanomolar range by the new compounds. hCA IV and VII were inhibited with KIs in the range of 29.7-708.8nM (hCA IV), and of 1.3-90.7nM (hCA VII). For hCA I and II the KIs were in the range of 6.7-335.2nM (hCA I) and of 0.5-55.4nM (hCA II). The structure-activity relationships (SAR) for the inhibition of these isoforms with the acridine-acetazolamide conjugates reported here were delineated.

A highly efficient magnetic solid acid nanocatalyst for the synthesis of new bulky heterocyclic compounds

Fe₃O₄nanoparticles were coated with 3-aminopropyltriethoxysilane and further chemically modified with maleic anhydride to generate Fe₃O₄@APTES·MAH NPs. Then some new bulky heterocyclic compounds were synthesized using this catalyst.

Nano-zirconia as an excellent nano support for immobilization of sulfonic acid: a new, efficient and highly recyclable heterogeneous solid acid nanocatalyst for multicomponent reactions

Nano-zirconia-supported sulfonic acid as a novel, highly efficient and recyclable heterogeneous nanocatalyst is reported for the synthesis of multicomponent reactions.

9-(5-Bromo-1H-indol-3-yl)-1,2,3,4,5,6,7,8,9,10-deca-hydro-acridine-1,8-dione dimethyl sulfoxide monosolvate

In the title compound, C₂₁H₁₉BrN₂O₂·C₂H₆OS, the indole ring system is essentially planar, with a maximum deviation of 0.050 (3) Å for the non-bridgehead C atom adjacent to the N atom. The two cyclo­hex-2-enone rings adopt half-chair conformations. An intra­molecular C—H⋯O hydrogen bond occurs. The solvent mol­ecule exhibits minor disorder of the S atom [site occupancies = 0.8153 (16) and 0.1847 (18)]. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds, forming layers parallel to the bc plane.

3,3,6,6-Tetra-methyl-9-(1-methyl-1H-indol-2-yl)-1,2,3,4,5,6,7,8,9,10-deca-hydro-acridine-1,8-dione

In the acridine system of the title mol-ecule, C26H30N2O2, both cyclo-hex-2-enone rings adopt sofa conformations. The indole ring system is essentially planar, with a maximum deviation of 0.017 (2) Å for a bridgehead C atom. An intra-molecular C-H⋯O hydrogen bond occurs. The mol-ecules assemble into C(6) chains in the crystal by way of N-H⋯O hydrogen bonds.

Some arylacridine derivatives possessing potassium channel opening activity

In this study, six new 2,2,7,7-tetramethyl-9-aryl-2,3,4,5,6,7,9,10-octahydro-1,8-acridinedione derivatives (1-6) were synthesised and their functional effects on vascular potassium channels and mechanism of induced relaxations on phenylephrine-induced contractile responses in isolated rat mesenteric arteries were investigated. Pinacidil was used as standard potassium channel opener. Compounds 1, 2, 5, 6 and pinacidil induced concentration-dependent relaxation response of vessel rings previously contracted with phenylephrine.