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[2,2'-Bipyrrolidine]-1,1'-disulfonic acid was easily prepared and recognized as a novel acidic catalyst through the reaction of 2,2'-bipyrrolidine with chlorosulfonic acid in CH2Cl2 at 0–5°C. The size and other properties of the prepared reagent were studied using FT-IR, 1H, 13C NMR, SEM, and also TGA analysis. After structural studies the efficiency of this reagent in the preparation of bis-triazoloquinazolinone derivatives via five-component one-pot reaction between bis-aldehydes, β-diketones and 3-amino-1,2,4-triazole was investigated. Operational simpleness, high yields, short reaction times and wide applicability are the key features of this methodology. All new products were characterized by using FT-IR, 1H, 13C NMR spectroscopy and elemental analyses. [ABSTRACT FROM AUTHOR]

An expedient strategy is reported for the synthesis of novel bis(thiazolidinones). This strategy involves a one-pot, multi-component reaction of bis-aldehydes, aromatic amines and thioglycolic acid in benzene at reflux. A two-steps approach to the synthesis of target compounds has also been studied. Anticancer activity of the synthesized compounds against some cancer cell lines was assessed. [ABSTRACT FROM AUTHOR]

A novel series of bis(tetrahydro[1,2,4]triazolo[5,1-b]quinazolin-8-ones) and bis(tetrahydrobenzo[4,5]imidazo[2,1-b]quinazolinones) containing amide linkages were regionselectively prepared via a three-component reaction of bis(aldehydes) with dimedone and 3-amino-1,2,4-triazole (or 2-aminobenzimidazole) under conventional heating as well as under microwave irradiation. [ABSTRACT FROM AUTHOR]

Aromatic bis-aldehydes have been used as building blocks in the synthesis of polyazomethines (a class of conjugated Schiff bases) and their physicochemical properties have been studied. Six dialdehydes have been synthesized, 3a-3f, via etherification reaction between aromatic diols (2a-2f) and 4-fluorobenzaldehyde (1) (see Scheme ), and then polymerized with 1,4-phenylenediamine (4a) and 4,4′-oxydianiline (4b) (see Scheme ). The chemical structures of the bis-aldehydes were elucidated by FTIR, 1H NMR and 13C NMR spectroscopic studies, elemental analysis and single crystal whereas the polymers were studied by FTIR and NMR spectroscopy. Their physicochemical properties were examined by their inherent viscosity, organosolubility, differential scanning calorimetry, X-ray powder diffraction, thermogravimetric analysis, solvatochromism, and photoluminescence. We report the electrical conductivity of each polymer measured by the four probe method. The results indicate that the electrical conductivity of polymers lies in range 0.019–0.051 mScm−1 which is reasonably higher than any reported value.

The asymmetric unit of the title compound, C22H14O6, consists of two independent molecules differing in the orientations of the ester groups. In one molecule, the two terminal benzene rings are inclined to the central benzene ring by 4.99 (13) and 77.46 (13)°, while in the other the corresponding angles are 11.03 (13) and 88.09 (12)°. In the crystal, molecules are connected into a ribbon structure running along [101] via C—H...O and C—H...π interactions. Adjacent ribbons are further linked by additional C—H...O and C—H...π interactions. The crystal studied was a non-merohedral twin [twin law (0.986 − 0.073 − 0.008, 0.323 1.036 0.148, −0.121 − 0.102 0.942)], the ratio of components being 0.937 (4):0.063 (4).

A novel series of bis(tetrahydro[1,2,4]triazolo[5,1- b]quinazolin-8(4 H)-ones) were prepared in a regioselective manner via a three component reaction of bis-aldehydes with 5-amino-1,2,4-triazole and dimedone under microwave irradiation as well as under conventional heating. The reactions were carried out in the absence as well as in the presence of ZnO nanoparticles as a heterogeneous catalyst. Best results were achieved when these reactions were carried out under MW heating. The presence of ZnO nanoparticles was found to improve the yields of the reactions but did not change the regioselectivity the products. The reaction mechanism and the unambiguous structural elucidation of the expected regioisomers were studied using DFT calculations as well as 2D-HMBC spectroscopy. Graphical abstract: [ABSTRACT FROM AUTHOR]

Bis-aldehyde monomers 4-(4′-formyl-phenoxy)benzaldehyde (3a), 3-methoxy-4-(4′-formyl-phenoxy)benzaldehyde (3b), and 3-ethoxy-4-(4′-formyl-phenoxy)benzaldehyde (3c) were synthesized by etherification of 4-fluorobenzaldehyde (1) with 4-hydroxybenzaldehyde (2a), 3-methoxy-4-hydroxybenzaldehyde (2b), and 3-ethoxy-4-hydroxybenzaldehyde (2c), respectively. Each monomer was polymerized with p-phenylenediamine and 4,4′-diaminodiphenyl ether to yield six poly(azomethine)s. Single crystal X-ray diffraction structures of 3b and 3c were determined. The structural characterization of the monomers and poly(azomethine)s was performed by FT-IR and NMR spectroscopic techniques and elemental analysis. Physicochemical properties of polymers were investigated by powder X-ray diffraction, thermogravimetric analysis (TGA), viscometry, UV−vis, spectroscopy and photoluminescence. These polymers were subjected to electrical conductivity measurements by the four-probe method, and their conductivities were found to be in the range 4.0 × 10−5 to 6.4 × 10−5 Scm−1, which was significantly higher than the values reported so far.

An efficient route for the synthesis of novel bis(1,4-dihydropyrano[2,3- c ]pyrazole-5-carbonitrile) derivatives is reported. The synthetic pathway involves one pot, synthesis of bis-aldehydes, malononitrile, and pyrazolone in the presence of pyridine. The anticancer activity of the synthesized products against MCF7, HEPG2, and A549 cell lines was assessed. Docking studies were performed and indicated the best binding mode compared to the standard ligand sorafenib. [ABSTRACT FROM AUTHOR]

Aromatic bis-aldehydes have been used as building blocks in the synthesis of polyazomethines (a class of conjugated Schiff bases) and their physicochemical properties have been studied. Six dialdehydes have been synthesized, 3a-3f, via etherification reaction between aromatic diols (2a-2f) and 4-fluorobenzaldehyde (1) (see Scheme 1), and then polymerized with 1,4-phenylenediamine (4a) and 4,4′-oxydianiline (4b) (see Scheme 2). The chemical structures of the bis-aldehydes were elucidated by FTIR, 1H NMR and 13C NMR spectroscopic studies, elemental analysis and single crystal whereas the polymers were studied by FTIR and NMR spectroscopy. Their physicochemical properties were examined by their inherent viscosity, organosolubility, differential scanning calorimetry, X-ray powder diffraction, thermogravimetric analysis, solvatochromism, and photoluminescence. We report the electrical conductivity of each polymer measured by the four probe method. The results indicate that the electrical conductivity of polymers lies in range 0.019–0.051 mScm−1 which is reasonably higher than any reported value. [ABSTRACT FROM AUTHOR]

A facile synthetic approach was adopted towards the synthesis of benzo-fused macrocyclic lactams 2a- 2g via the base-catalyzed condensation reaction of 2,2′-[alkanediylbis(oxy)]bis[benzaldehydes] 3a- 3c with N, N′-substituted bis[2-cyanoacetamide] derivatives 7a- 7c ( Scheme 2). The latter compounds were obtained by the reaction of the appropriate diamines 6a- 6c with ethyl 2-cyanoacetate ( 4). Attempts to prepare the oxaaza macrocycles 2 by alternative pathways were also investigated. The novel pyrazolo-fused macrocycles 13a and 13b were obtained in 48 and 52% yield, respectively, upon treatment of 2d and 2g with NH2NH2⋅H2O at 100° ( Scheme 4). [ABSTRACT FROM AUTHOR]

Reactions of N-isocyaniminotriphenylphosphorane (Ph3PNNC) with aromatic bis-aldehydes (isophthalaldehyde and terphthalaldehyde) in the presence of 3-phenyl-2-propynoic acid and secondary amines proceed smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeds smoothly and cleanly under mild conditions and no side reactions were observed. [ABSTRACT FROM AUTHOR]

A new bis schiffbases, 3 a-b were synthesized compound 2 with various bis aldehydes. Compounds 3 a-b have been reduced with NaBH4 to afford the corresponding bis amino triazole compounds 4 a-b. The obtained products 3 a-b and 4 a-b were identified by FTIR, 1H-NMR, 13C-NMR. A series of triazol derivatives were evaluated for their antibacterial, antioxidant, antiurease and antielastase activities. The results showed that the synthesized new bis-1,2,4-triazole derivatives had effective antioxidant, antiurease and antielastase activities. [ABSTRACT FROM AUTHOR]

New bis(thiadiazole) derivatives 7a-m were prepared in good yields by the reaction of the appropriate hydrazonoyl halides 4a-e with the bis-Schiff bases 9a-c. Similarly, the bis(thiadiazole) derivatives 17a-g were prepared by the reaction of the novel bis-hydrazonoyl halides 13a-d with schiff bases 3a-d. [ABSTRACT FROM AUTHOR]

Bis-aldehyde monomers 4-(4′-formyl-phenoxy)benzaldehyde (3a), 3-methoxy-4-(4′-formyl-phenoxy)benzaldehyde (3b), and 3-ethoxy-4-(4′-formyl-phenoxy)benzaldehyde (3c) were synthesized by etherification of 4-fluorobenzaldehyde (1) with 4-hydroxybenzaldehyde (2a), 3-methoxy-4-hydroxybenzaldehyde (2b), and 3-ethoxy-4-hydroxybenzaldehyde (2c), respectively. Each monomer was polymerized with p-phenylenediamine and 4,4′-diaminodiphenyl ether to yield six poly(azomethine)s. Single crystal X-ray diffraction structures of 3b and 3c were determined. The structural characterization of the monomers and poly(azomethine)s was performed by FT-IR and NMR spectroscopic techniques and elemental analysis. Physicochemical properties of polymers were investigated by powder X-ray diffraction, thermogravimetric analysis (TGA), viscometry, UV–vis, spectroscopy and photoluminescence. These polymers were subjected to electrical conductivity measurements by the four-probe method, and their conductivities were found to be in the range 4.0 × 10−5 to 6.4 × 10−5 Scm−1, which was significantly higher than the values reported so far. [ABSTRACT FROM AUTHOR]

Aromatic bis -aldehydes have been used as building blocks in the synthesis of polyazomethines (a class of conjugated Schiff bases) and their physicochemical properties have been studied. Six dialdehydes have been synthesized, 3a-3f , via etherification reaction between aromatic diols ( 2a-2f ) and 4-fluorobenzaldehyde ( 1 ) (see Scheme 1), and then polymerized with 1,4-phenylenediamine ( 4a ) and 4,4'-oxydianiline ( 4b ) (see Scheme 2). The chemical structures of the bis -aldehydes were elucidated by FTIR, 1 H NMR and 13 C NMR spectroscopic studies, elemental analysis and single crystal whereas the polymers were studied by FTIR and NMR spectroscopy. Their physicochemical properties were examined by their inherent viscosity, organosolubility, differential scanning calorimetry, X-ray powder diffraction, thermogravimetric analysis, solvatochromism, and photoluminescence. We report the electrical conductivity of each polymer measured by the four probe method. The results indicate that the electrical conductivity of polymers lies in range 0.019-0.051 mScm -1 which is reasonably higher than any reported value.