Development of CuMnO (x = 2, and y = 4)-GO heterostructure for the synthesis of pyranoquinoline derivatives.

The pyranoquinoline derivatives are synthetically important due to their biological properties. In this research, these derivatives were produced through an environmentally friendly method. This method includes the use of CuMnO (x = 2, and y = 4)-GO as a nanocatalyst, which is easy to produce, has excellent performance, cost-effectiveness, and recyclability among its features, and also the use of water as a green solvent.

Zn Complex on Tryptophan-Functionalized MCM-41 as an Efficient and Promising Reusable Nanocatalyst in One-Pot Three-Component Synthesis of Amino Benzyl Quinolinols and Naphthols via a Betti Reaction.

In this research, a Zn transition metallic complex on functionalized mesopore silica MCM-41 has been designed and utilized as an effective, recoverable, and thermally stable heterogeneous nanocatalyst in the formation of the C-C bond. Also, the synthesis of amino benzyl quinolinols and amino benzyl naphthol derivatives was performed by the three-component reaction of Betti from aromatic aldehydes, type II amines, and 8-hydroxyquinoline and 1-naphthol in the presence of the MCM-41-tryptophan-Zn nanocatalyst under reflux conditions. The short reaction times, high efficiency of the products, the easy separation of catalysts due to their heterogeneity, and their reusability are the advantages of this method.

A novel strategy for stabilization of sub-nanometric Pd colloids on kryptofix functionalized MCM-41: nanoengineered material for Stille coupling transformation.

The stabilization of sub-nanometric metal particles (< 1 nm) with suitable distribution remained challenging in the catalytic arena. Herein, an intelligent strategy was described to anchoring and stabilizing sub-nanometric Pd colloids with an average size of 0.88 nm onto Kryptofix 23 functionalized MCM-41.

Degradation of ciprofloxacin using hematite/MOF nanocomposite as a heterogeneous Fenton-like catalyst: A comparison of composite and core-shell structures.

A novel strategy was described to fabricate hematite-MOF materials with morphologies (core-shell) and (composite) as an efficient peroxymonosulfate (PMS) activator for degrading ciprofloxacin (CIP) antibiotics. First, α-FeO nanoparticles (NPs) with a size distribution range of 80 nm were prepared by surfactant-assisted reflux method. Then, cobalt-based metal-organic framework (ZIF-67) was grown onto the α-FeO NPs with ultrasonic and solvothermal method, which can control the nanostructures morphology.

Cu-Kojic Acid Complex Anchored to Functionalized Silica-MCM-41: A Promising Regioselective and Reusable Nanocatalyst for Click Reaction.

Cu-Kojic acid (KA) complex anchored to functionalized silica-MCM-41 was synthesized via the process of postgrafting and introduced as an effective, new, reusable, and thermally resistant heterogeneous nanocatalyst for the clean synthesis of 1-1,2,3-triazoles from Click reaction of 2-(azidomethyl)-5-benzyloxy-4-pyrone and azido Kojic acid with a variety of terminal alkynes in excellent yields. The structure of nanocatalyst was analyzed by ICP, BET, XRD, EDS, SEM, TGA, TEM, and FT-IR techniques.

Injectable thermosensitive hybrid hydrogel containing graphene oxide and chitosan as dental pulp stem cells scaffold for bone tissue engineering.

Here, we fabricated thermosensitive injectable hydrogel containing poly (N-isopropylacrylamide) (PNIPAAm)-based copolymer/graphene oxide (GO) composite with different feed ratio to chitosan (CS) as a natural polymer through physical and chemical crosslinking for the proliferation and differentiation of the human dental pulp stem cells (hDPSCs) to the osteoblasts. The PNIPAAm copolymer/GO composite was synthesized by free-radical copolymerization of (N-isopropylacrylamide) (NIPAAm), itaconic acid (IA) and maleic anhydride-modified poly(ethylene glycol) (PEG) in the presence of GO and used for the preparation of the hydrogels. The formulated hydrogels were evaluated for the porous architecture, rheological behavior, compressive strength, swelling property, in vitro degradation, hemocompatibility, biocompatibility, and differentiation.

Bioactive polymeric scaffolds for osteogenic repair and bone regenerative medicine.

The loss of bone tissue is a striking challenge in orthopedic surgery. Tissue engineering using various advanced biofunctional materials is considered a promising approach for the regeneration and substitution of impaired bone tissues. Recently, polymeric supportive scaffolds and biomaterials have been used to rationally promote the generation of new bone tissues.

A facile and regioselective one-pot synthesis of novel pyrazolo[1[Formula: see text],5[Formula: see text]:1,2]pyrrolo[3,4-b]quinoline-2,3-dicarboxylate hybrids via intramolecular Wittig reaction.

The regioselective syntheses of novel pyrazolo[1[Formula: see text],5[Formula: see text]:1,2]pyrrolo[3,4-b]quinoline-2,3-dicarboxylates (6a-l) from pyrrolo([3,4-b]quinolin-2(3H)-yl)benzamides through an intramolecular Wittig reaction are described. This protocol takes advantages of mild conditions, simple workup and high yield which make this method attractive for the synthesis of these hybrid of pyrazolo[1[Formula: see text],5[Formula: see text]:1,2]pyrrolo[3,4-b]quinolines.

Isotopic splitting patterns in the (13) C NMR spectra of some partially deuterated 1-aryl-2-(phenyldiazenyl)butane-1,3-dione and 4-hydroxy-3-(phenyldiazenyl)-2H-chromen-2-one: evidence for elucidation of tautomeric forms.

Nuclear magnetic resonance spectra of synthesized azo dyes derived from aniline derivatives in reaction with benzoylacetone and 4-hydroxycoumarin were studied in both CDCl3 and (CD3 )2 SO (two drops of D2 O were added into solutions of dyes). All dyes showed intramolecular hydrogen bonding. Dyes derived from o-nitro aniline in the reaction with benzoylacetone, and 4-hydroxycoumarin showed bifurcated intramolecular hydrogen bonds.

Isotopic effect on tautomeric behavior of 5-(2,6-disubstituted-aryloxy)-tetrazoles.

Isotopic effect on tautomeric behaviors of the synthesized 5-phenoxy- (1a), 5-(2,6-dimethylphenoxy)-(1b), 5-(2,6-diisopropylphenoxy)-(1c), 5-(2,6-dimethoxyphenoxy)-(1d) and 5-(4-methylphenoxy)-tetrazole (1e) were investigated in DMSO-d6 by adding one drop of D2O. Among 1a-e, 1a, 1d and 1e show small rotational barrier around C5-O1 and O1-C6 while in 1b and 1c there are distinguishable rotational barrier about that bonds. The (1)H NMR spectra of 1b and 1c show slightly different chemical shifts for two methyl and isopropyl groups on those phenyl ring, respectively, while the chemical shifts difference (Δδ) between two methyl and two isopropyl groups were enhanced by adding D2O.

New one-pot synthesis of spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]pentaones and their sulfur analogues.

Reaction of barbituric acid (BA), 1,3-dimethyl barbituric acid (DMBA) and 2-thiobarbituric acid (TBA) with cyanogen bromide and various aldehydes in presence of triethylamine afforded a new class of heterocyclic stable 5-alkyl and/or 5-aryl-1H, 1'H-spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine]2,2',4,4',6'(3H,3'H,5H)-pentaones which are dimeric forms of barbiturate (uracil and thiouracil derivatives) at 0 °C to ambient temperatures. Structure elucidation is proved by X-ray crystallography, (1)H NMR, (13)C NMR, FT-IR, CHN and mass analyses techniques. Mechanisms of the formations are discussed.

Tautomerism and isotopic multiplets in the 13C NMR spectra of partially deuterated 3-arylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones and their sulfur analogs--evidence for elucidation of the structure backbone and tautomeric forms.

The tautomerism of the synthesized 3-arylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones (1a-d) and 3-aryl-7-thioxo-7,8-dihydro-6H-pyrimido[4,5-c]pyridazine-5-ones (2a-d) was studied in dimethyl sulfoxide (DMSO)-d(6). (1)H NMR spectra of 1a-d showed a clustered water molecule in the structure backbone that is attached by strong intermolecular H bonding. The relation between the temperature and H bonding of the clustered water molecule with 1a was also studied as representative.

Tautomeric behaviour and isotopic multiplets in the 13C NMR spectra of partially deuterated 5-arylazo-pyrimidine (1H,3H,5H)-2,4,6-triones and 5-arylazo-2-thioxo-pyrimidine (1H,3H,5H)-4,6-diones-evidence for elucidation of tautomeric forms.

NMR spectra of the synthesized azo dyes, 5-arylazo-pyrimidine (1H,3H,5H)-2,4,6-triones (5a-g), 1,3-dimethyl-5-arylazo-pyrimidine (1H,3H,5H)-2,4,6-triones (6a-g), and 5-arylazo-2-thioxo-pyrimidine (1H,3H,5H)-4,6-diones (7a-g) were studied in (CD(3))(2)SO (three drops of CD(3)OD were added into solutions of the dyes in two different concentrations). All dyes showed intramolecular hydrogen bonding. Dyes 5a-7a showed bifurcated intramolecular hydrogen bonds.

1,1',3,3',5,5'-Hexamethyl-spiro-[furo[2,3-d]pyrimidine-6(5H),5'-pyrimidine]-2,2',4,4',6'(1H,3H,1'H,3'H,5'H)-penta-one.

In the title mol-ecule, C(15)H(18)N(4)O(6), the fused 2,3-dihydro-furan ring has an envelope conformation and the spiro pyrimidine ring has a half-chair conformation. In the crystal, short inter-molecular O⋯C contacts of 2.835 (4) and 2.

5-(2,6-Dimethoxy-phen-oxy)-2-methyl-sulfanylmethyl-2H-tetra-zole.

In the title mol-ecule, C(11)H(14)N(4)O(3)S, the tetra-zole and benzene rings are nearly perpendicular to each other, forming a dihedral angle of 104.93 (14)°. The crystal packing exhibits weak inter-molecular C-H⋯O hydrogen bonds.

NMR investigation of methyl-2,4-dimethoxysalicylate: effect of solvent and temperature.

(1)H NMR and (13)C NMR of methyl-2,4-dimethoxysalicylate 2 was measured in chloroform-d at the temperature range of 220-330 K, in dimethyl sulfoxide-d(6) at the temperature range of 300-400 K and in a polar protic solvent (CD(3)OD) at 300 K. The structure of 2 in liquid phase (solvent) is compared with those in solid phase (X-ray) and in the gas phase (quantum mechanical calculations). The relationship between molecular geometry, (1)H NMR chemical shift and W coupling of involved protons has a complex nature, but hydrogen bonds [C=O.