Synthesis of new Schiff bases bearing 1,2,4-triazole, thiazolidine and chloroazetidine moieties and their pharmacological evaluation.

New compounds based on oxindole moiety were synthesized via the reaction of 5-substitued isatins 1a-e with different nucleophiles such as benzidine, 3,3'-dimethoxybenzidine 2a,b and 2,6-diaminopyridine 3 to afford three different classes of bis-Schiff bases 4a-e, 5a-e and 6a-e, respectively. The structures of the new compounds were elucidated on the basis of their FTIR, 1H NMR, 13C NMR, GC/MS spectral data and elemental analysis. The in vitro antimicrobial activity of the new compounds was evaluated using a broth dilution technique in terms of minimal inhibitory concentration (MIC) against four bacterial and two fungal pathogens and anticancer activities against HELA cervix. The revealed data showed that compound 9d has excellent activity against Gram + ve and Gram -ve bacteria, and compounds 11b presented promising anticancer activity against HELA cervix. [Formula: see text].

New pyrano[2,3-c]pyridazine derivatives with antimicrobial activity synthesized using piperidine as the organocatalyst.

A simple and efficient method for the synthesis of highly diverse pyrano[2,3-c]pyridazines was achieved by a one pot multicomponent reaction using piperidine as the organocatalyst. The synthesis of a series of heterocyclic derivatives with varying functionality (e.g. thiazine, tetrazole and pyrimidine) incorporating the pyrano[2,3-c]pyridazine moiety were achieved via reaction of 2a-e with different reagents. The structures of the synthesized derivatives were elucidated by FTIR, MS, (1)H and (13)C NMR spectroscopy. A number of the newly synthesized targeted compounds 2b-e, 3a-c and 4a-c were evaluated for their in vitro antibacterial activity and were compared with chloramphenicol and nystatin as broad spectrum reference standard antibiotics. Tests were carried out against Staphylococcus aureus (MTCC3160) and Enterococcusi fecalis as Gram-positive bacteria, and Escherichia coli (MTCC1652) and Klebsiella pneumonia as Gram-negative bacteria. Antifungal potential against Candida albicans, and Aspergillus albicans strains were also evaluated. The results revealed that compounds 3a and 3c showed strong significant activity relative to the reference against these bacterial and fungal strains.

Synthesis and in vitro biological evaluation of new heterocycles based on the indole moiety.

New compounds based on the indole moiety were synthesized via the reaction of indole-3-carbinal 1 with different nucleophiles such as 6-aryl-[4-(2-methoxybenzyl)pyridazin-3-yl] hydrazones 2a-c, benzidine, 3,3'-dimethoxybenzidine 4a,b and 2,6-diaminopyridine 6 to afford hydrazine derivatives 3a-c and three different classes of bis-Schiff bases. The structures of the new compounds were elucidated on the basis of their FTIR, (1)H NMR, (13)C NMR spectral data, GC/MS and elemental analysis. The antimicrobial activity of the new compounds was evaluated using a broth dilution technique in terms of minimal inhibitory concentration (MIC) against four pathogenic bacteria and two pathogenic fungi strains. Compound 14b showed excellent activity against Escherichia coli and Klebsiella pneumoniae. Some of the prepared compounds were tested for anti-cancer activity against human cell lines HCT116 (colon), MCF7 (breast) and HELA (cervix). From the results of the in vitro assays, compounds 3a,b, and 18a,c presented promising anti-cancer activity.

Therapeutic applications of sustainable new chitosan derivatives and its nanocomposites: Fabrication and characterization.

Chitosan (CS) is a biologically active biopolymer used in different medical applications due to its biodegradability, biocompatibility, and nontoxicity. Nanotechnology is an exciting and quick developing field in medical applications. Nanoparticles have shown great potential in the treatment of cancer and inflammation. In the present work modification of chitosan and its (Ag, Au, or ZnO) nanocomposites by N-aminophthalimide (NAP) occurred through the reaction with epichlorohydrin (ECH) as a crosslinker in the presence or absence of glutaraldehyde (GA) under different reaction conditions using microwave irradiation to give modified chitosan derivatives CS-2, CS-6, and their nanocomposites. Modified chitosan derivatives were characterized using different tools. CS-2 and CS-6 derivatives displayed enhancement of thermal stability and crystallinity compared to chitosan. Additionally, CS-2, CS-6, and their nanocomposites exhibited improvements in antitumor activity against HeLa cancer cells and enzymatic inhibitory against trypsin and α-chymotrypsin enzymes compared to chitosan. However, CS-2 revealed the highest cell growth inhibition% toward HeLa cells (89.02 ± 1.46 %) and the enzymatic inhibitory toward α-chymotrypsin enzyme (17.13 ± 1.59 %). Furthermore, CS-Au-2 showed the highest enzymatic inhibitory against trypsin enzyme (28.14 ± 1.76 %). These results suggested that the new chitosan derivatives CS-2, CS-6, and their nanocomposites could be a platform for medical applications against HeLa cells, trypsin, and α-chymotrypsin enzymes.

Fabrication and characterization of unique sustain modified chitosan nanoparticles for biomedical applications.

Chitosan (CS) is a biopolymer that offers a wide range in biomedical applications due to its biocompatibility, biodegradability, low toxicity and antimicrobial activity. Syringaldehyde (1) is a naturally occurring organic compound characterized by its use in multiple fields such as pharmaceuticals, food, cosmetics, textiles and biological applications. Herein, development of chitosan derivative with physicochemical and anticancer properties via Schiff base formation from the reaction of chitosan with sustainable eco-friendly syringaldehyde yielded the (CS-1) derivative. Moreover, in the presence of polyethylene glycol diglycidyl ether (PEGDGE) or sodium tripolyphosphate (TPP) as crosslinkers gave chitosan derivatives (CS-2) and (CS-3NPs) respectively. The chemical structures of the new chitosan derivatives were confirmed using different tools. (CS-3NPs) nanoparticle showed improvement in crystallinity, and (CS-2) derivative revealed the highest thermal stability compared to virgin chitosan. The cytotoxicity activity of chitosan and its derivatives were evaluated against HeLa (human cervical carcinoma) and HEp-2 (Human Larynx carcinoma) cell lines. The highest cytotoxicity activity was exhibited by (CS-3NPs) compared to virgin chitosan against HeLa cell growth inhibition and apoptosis of 90.38 ± 1.46% and 30.3% respectively and IC50 of 108.01 ± 3.94 µg/ml. From the above results, it can be concluded that chitosan nanoparticle (CS-3NPs) has good therapeutic value as a potential antitumor agent against the HeLa cancer cell line.

Microwave-assisted synthesis of antimicrobial agents based on pyridazine moiety.

An efficient and simple microwave assisted synthesis of sulfonamide derivatives incorporating the pyridazine moiety has been developed. These sulfonamides were used for the preparation of new heterocyclic compounds via reaction with different reagents using a microwave irradiation technique. The structures of the newly synthesized compounds were confirmed on the basis of FTIR, (1)H and (13)C-NMR, mass spectral techniques and elemental analyses. Some of the new synthesized compounds were assayed for their in vitro antibacterial activity against Gram-positive bacteria, Staphylococcus aureus and Staphylococcus epidermidis, Gram-negative bacteria, Escherichia coli and Klebsiella pneumonia and antifungal activity against Aspergillus fumigatus and Candida albicans. Most of the new compounds showed significant antibacterial and antifungal activity.

Synthesis of a new class of antimicrobial agents incorporating the indolin-2-one moiety.

New furanone derivatives incorporating the indolin-2-one moiety 3 were prepared via the Perkin reaction of isatins 1 with aroylpropionic acids 2 under conventional conditions or microwave irradiation. A series of functionally heterocyclic derivatives (e.g., pyridazines, pyrroles, and sulfonamides) incorporating the indolin-2-one moiety was achieved via reaction of 3 with different reagents under microwave irradiation conditions. The newly synthesized compounds were characterized on the basis of FTIR, (1)H, (13)C NMR and mass spectral studies. Some of the new synthesized compounds were screened for antibacterial activity against Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus), Gram-negative bacteria (Escherichia coli and Shigilla flexneri) and antifungal activity against Aspergillus flavus and Candida albicans. Compound 8 j was equipotent to chloramphenicol in inhibiting the growth of E. coli minimum inhibitory concentration (MIC 2.5 µg/mL). Compound 8j may possibly be used as a lead compound for developing a new antibacterial agents. The antibacterial activity is expressed as the corresponding MIC (µg/mL) values.

New potential anti-SARS-CoV-2 and anti-cancer therapies of chitosan derivatives and its nanoparticles: Preparation and characterization.

Chitosan (CS) is a biopolymer and has reactive amine/hydroxyl groups facilitated its modifications. The purpose of this study is improvement of (CS) physicochemical properties and its capabilities as antiviral and antitumor through modification with 1-(2-oxoindolin-3-ylidene)thiosemicarbazide (3A) or 1-(5-fluoro-2-oxoindolin-3-ylidene)thiosemicarbazide (3B) via crosslinking of poly(ethylene glycol)diglycidylether (PEGDGE) using microwave-assisted as green technique gives (CS-I) and (CS-II) derivatives. However, (CS) derivatives nanoparticles (CS-I NPs) and (CS-II NPs) are synthesized via ionic gelation technique using sodium tripolyphosphate (TPP). Structures of new (CS) derivatives are characterized using different tools. The anticancer, antiviral efficiencies and molecular docking of (CS) and its derivatives are assayed. (CS) derivatives and its nanoparticles show enhancement in cell inhibition toward (HepG-2 and MCF-7) cancer cells in comparison with (CS). (CS-II NPs) reveals the lowest IC50 values are 92.70 ± 2.64 µg/mL and 12.64 µ g/mL against (HepG-2) cell and SARS-CoV-2 (COVID-19) respectively and the best binding affinity toward corona virus protease receptor (PDB ID 6LU7) -5.71 kcal / mol. Furthermore, (CS-I NPs) shows the lowest cell viability% 14.31 ± 1.48 % and the best binding affinity -9.98 kcal/moL against (MCF-7) cell and receptor (PDB ID 1Z11) respectively. Results of this study demonstrated that (CS) derivatives and its nanoparticles could be potentially employed for biomedical applications.

New sustainable antimicrobial chitosan hydrogels based on sulfonamides and its nanocomposites: Fabrication and characterization.

Chitosan (Ch), a linear cationic biopolymer, has broad medical applications. In this paper, new sustainable hydrogels (Ch-3, Ch-5a, Ch-5b) based on chitosan/sulfonamide derivatives 2-chloro-N-(4-sulfamoylphenethyl) acetamide (3) and/or 5-[(4-sulfamoylphenethyl) carbamoyl] isobenzofuran-1,3-dione (5) were prepared. Hydrogels (Ch-3, Ch-5a, Ch-5b) were loaded (Au, Ag, ZnO) NPs to form its nanocomposites to improve the antimicrobial efficacy of chitosan. The structures of hydrogels and its nanocomposites were characterized using different tools. All hydrogels displayed irregular surface morphology in SEM, however hydrogel (Ch-5a) revealed the highest crystallinity. The highest thermal stability was shown by hydrogel (Ch-5b) compared to chitosan. The nanocomposites represented nanoparticle sizes <100 nm. Antimicrobial activity was assayed for hydrogels using disc diffusion method exhibited great inhibition growth of bacteria compared to chitosan against S. aureus, B. subtilis and S. epidermidis as Gram-positive, E. coli, Proteus, and K. pneumonia as Gram-negative and antifungal activity against Aspergillus Niger and Candida. Hydrogel (Ch-5b) and nanocomposite hydrogel (Ch-3/Ag NPs) showed higher colony forming unit (CFU) and reduction% against S. aureus and E. coli reaching 97.96 % and 89.50 % respectively in comparison with 74.56 % and 40.30 % for chitosan respectively. Overall, fabricated hydrogels and its nanocomposites enhanced the biological activity of chitosan and it can be potential candidates as antimicrobial drugs.

Antiproliferative effects of metal complexes of new isatin hydrazones against HCT116, MCF7 and HELA tumour cell lines.

New hydrazone ligands (HL) derived from 5-substituted isatins and 1-(4-(2-methoxybenzyl)-6-arylpyridazin-3-yl)hydrazines and its complexes with Co(II) and Cu(II) were synthesized. The new hydrazones and their complexes were characterized by means of elemental, spectral analyses and magnetic studies. Primary cytotoxicity evaluation of HL 5a and the new complexes showed that these complexes could act as anticancer agents since they reduced the growth of samples of human tumour cell lines (HCT116((Colon)), MCF7((Breast)) and HELA((Cervix))) to ≤18.5 µg/mL for the new complexes.

Synthesis, characterization and in vitro antimicrobial evaluation of new compounds incorporating oxindole nucleus.

New compounds incorporating with the oxindole nucleus were synthesized via the reaction of substituted isatins [5-methyl-, 5-chloro- and 1-hydroxymethyl isatins] with different nucleophiles. The structures of the newly compounds were elucidated on the basis of FTIR, (1)H NMR, (13)CMR spectral data, GC/MS and chemical analysis. Investigation of antimicrobial activity of the new compounds was evaluated using broth dilution technique in terms of minimal inhibitory concentration (MIC) count against four pathogenic bacteria and two pathogenic fungi. Most of the new compounds are significantly active against bacteria and fungi. MIC showed that compound (4a) possesses higher effect on Gram-positive bacteria Bacillus cereus than the selected antibacterial agent sulphamethoxazole, whereas compound (11c) possesses more activity against Gram-negative bacteria Shigella dysenterie.

Synthesis and characterization of polystyrene with embedded silver nanoparticle nanofibers to utilize as antibacterial and wound healing biomaterial.

Herein, silver nanoparticles (Ag) embedded in polystyrene (PS) nanofiber composites have been prepared by an electrospinning technique using N, N-dimethylformamide (DMF) as a solvent and safe reducing agent. Electrospinning of polystyrene (PS) solutions is conducted using different electrospinning parameters such as polymer concentration in the electrospinning solution; solution feed rate, and electrical field strength. Then silver nanoparticles (AgNPs) were embedded into PS nanofibers to obtain an AgNPs-PS nanofiber composite as a powerful, cheap, and nontoxic bioactive material. PS nanofibers and AgNPs-PS nanofibers composite were characterized by using thermogravimetric analysis (TGA), X-ray diffraction, and scanning electron microscopy (SEM). Also, AgNPs were characterized by UV-vis spectroscopy, transmission electron microscopy (TEM), and EDX analysis. Results showed that PS nanofibers were obtained with concentrations ranging from 10-30 wt.% in DMF solvent. Also, an AgNPs-PS nanofiber composite has been produced from its solutions by using DMF at the optimum value. The prepared AgNPs have a 21-40 nm particle size and a semi-spherical shape. In addition, the antibacterial activity of AgNPs-PS nanofibers towards both Gram-positive and Gram-negative bacteria has been increased. Therefore, this nanocomposite can be used as a powerful bioactive material in biomedical fields.

New chitosan derivatives inspired on heterocyclic anhydride of potential bioactive for medical applications.

In the present work new chitosan derivatives inspired heterocyclic anhydride were prepared to improve the biological activities of chitosan via imidization reaction of chitosan (CS) and N-(1,3-dioxoisoindolin-2-yl)-1,3-dioxo-1,3-dihydroiso-benzofuran-5-carboxamide (5) to yield amic acid CS-6 at room temperature and imide CS-8 thermally. However, the reaction between (CS) and anhydride (5) in presence of sodium tripolyphosphate (TPP) or Poly (ethylene glycol) diglycidyl ether (PEGDG) at room temperature yielded CS-6 NPs and CS-7 respectively. The structure of new chitosan derivatives was characterized using morphological and spectroscopic analyses. From evaluation of the biological activities, the greatest enzymatic inhibitory for trypsin and α-chymotrypsin revealed by CS-7 at 88.33 ± 2.27 and 79.63 ± 3.16% respectively. Furthermore, the highest inhibition zones, (MIC) and (MBC) against S. aureus and B. subtilis recorded by CS-6 NPs at 21 ± 0.75, 22 ± 0.98 mm, 19.5, 19.5, 38 and 38 ppm respectively. Additionally, CS-8 displayed the best cell growth inhibition against vero cell line at 93.17 ± 0.29%.

Iron Oxide Nanoparticles: Physicochemical Characteristics and Historical Developments to Commercialization for Potential Technological Applications.

Iron oxide nanoparticles (IONPs) have gained increasing attention in various biomedical and industrial sectors due to their physicochemical and magnetic properties. In the biomedical field, IONPs are being developed for enzyme/protein immobilization, magnetofection, cell labeling, DNA detection, and tissue engineering. However, in some established areas, such as magnetic resonance imaging (MRI), magnetic drug targeting (MDT), magnetic fluid hyperthermia (MFH), immunomagnetic separation (IMS), and magnetic particle imaging (MPI), IONPs have crossed from the research bench, received clinical approval, and have been commercialized. Additionally, in industrial sectors IONP-based fluids (ferrofluids) have been marketed in electronic and mechanical devices for some time. This review explores the historical evolution of IONPs to their current state in biomedical and industrial applications.

Novel hydrazinocurcumin derivative loaded chitosan, ZnO, and au nanoparticles formulations for drug release and cell cytotoxicity.

Synthesis of new hydrazinocurcumin derivative 4-((E)-2-(1-(4-Methoxy benzyl)-6-p-tolylpyridazin-3-yl)-3-((E)-4-hydroxy-3-methoxystyryl)-1H-pyrazol-5-yl)vinyl)-2-methoxyphenol (HCUR) through the reaction of curcumin (CUR) with 1- (4-(2-Methoxybenzyl)-6-p-tolylpyridazin-3-yl)hydrazine(VII). Nanoparticles formulations of (HCUR) loaded chitosan (CS), ZnO, Au, CS-ZnO and CS-Au NPs, via self-assembling process were developed to give CS-HCUR NPs, ZnO-HCUR NPs, Au-HCUR NPs, CS-ZnO-HCUR NPs and CS-Au-HCUR NPs. Chemical structures of (HCUR) and (HCUR) loaded nanoparticles formulations were characterized by UV-Vis, FTIR, Mass Spectrum, Elemental Analysis, 1HNMR, 13CNMR, TGA, DSC, SEM and TEM. The particle size of the nanoformulations ranged from 16.8 to 59.6 nm. NPs formulations were used as delivery system to sustain controlled drug delivery. Drug release profiles and cytotoxicity of NPs formulations against HCT-116 (colon carcinoma) and HepG-2 (hepatocellular cancer) cell lines were investigated. Drug release studies showed that by decreasing the pH value of release medium from 7.4 to 5.4 increased the release rate of (HCUR) from the NPs formulations. Cell viability study proved that NPs formulations revealed higher activity against HCT- 116 cell than (CUR) especially CS-HCUR NPs which displayed the most active with cell viability 1.80%. Moreover, ZnO-HCUR NPs expressed as the highest cytotoxic effect against HepG-2 cell with cell viability 0.98%.

Sustainable antimicrobial modified chitosan and its nanoparticles hydrogels: Synthesis and characterization.

The target of the present study is the development of sustainable chitosan and chitosan nanoparticles-based heterocyclic compound hydrogels with antimicrobial properties. Sustainable antimicrobial new modified chitosan hydrogel (CS-3) was synthesized by the reaction of chitosan (CS) with 2-([4-[(1, 3-dioxoisoindolin-2-ylimino) methyl] phenyl] methyleneamino) isoindoline-1, 3-dione (3) via ring opening of cyclic imide moiety in compound (3). However, the modified chitosan nanoparticles hydrogel (CS-3 NPs) were prepared in-situ by an ionotropic gelation technique using sodium tripolyphosphate (TPP) as the cross-linking agent. The prepared hydrogels were characterized by FTIR, SEM, TEM, TGA, DSC and elemental analysis. The hydrogels were tested versus eight pathogenic strains of Gram +ve and Gram -ve bacteria and two fungi. The results revealed that hydrogels (CS-3) and (CS-3 NPs) showed higher antimicrobial activities than virgin (CS) and (CS-NPs). However, hydrogel (CS-3 NPs) showed the highest Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) especially with Gram +ve bacteria (S. pyogenes) at 19.5 and 39 µg/ml compared to the standard antibiotic Ciprofloxacin at 19 and 38 µg/ml respectively.

Nanoscale Thermosensitive Hydrogel Scaffolds Promote the Chondrogenic Differentiation of Dental Pulp Stem and Progenitor Cells: A Minimally Invasive Approach for Cartilage Regeneration.

PURPOSE: Several scaffolds and cell sources are being investigated for cartilage regeneration. The aim of the study was to prepare nanocellulose-based thermosensitive injectable hydrogel scaffolds and assess their potential as 3D scaffolds allowing the chondrogenic differentiation of embedded human dental pulp stem and progenitor cells (hDPSCs). MATERIALS AND METHODS: The hydrogel-forming solutions were prepared by adding ß-glycerophosphate (GP) to chitosan (CS) at different ratios. Nanocellulose (NC) suspension was produced from hemp hurd then added dropwise to the CS/GP mixture. In vitro characterization of the prepared hydrogels involved optimizing gelation and degradation time, mass-swelling ratio, and rheological properties. The hydrogel with optimal characteristics, NC-CS/GP-21, was selected for further investigation including assessment of biocompatibility. The chondrogenesis ability of hDPSCs embedded in NC-CS/GP-21 hydrogel was investigated in vitro and compared to that of bone marrow-derived mesenchymal stem cells (BMSCs), then was confirmed in vivo in 12 adult Sprague Dawley rats. RESULTS: The selected hydrogel showed stability in culture media, had a gelation time of 2.8 minutes, showed a highly porous microstructure by scanning electron microscope, and was morphologically intact in vivo for 14 days after injection. Histological and immunohistochemical analyses and real-time PCR confirmed the chondrogenesis ability of hDPSCs embedded in NC-CS/GP-21 hydrogel. CONCLUSION: Our results suggest that nanocellulose-chitosan thermosensitive hydrogel is a biocompatible, injectable, mechanically stable and slowly degradable scaffold. hDPSCs embedded in NC-CS/GP-21 hydrogel is a promising, minimally invasive, stem cell-based strategy for cartilage regeneration.

Chitosan nanoparticle hydrogel based sebacoyl moiety with remarkable capability for metal ion removal from aqueous systems.

In this present study, a new modified chitosan hydrogel, Cts-SC NPs, was prepared from a one pot reaction of sebacoyl chloride (SC) with chitosan in the presence of 1% v/v glacial acetic acid and 1% w/v sodium tripolyphosphate (TPP) using an ionotropic gelation technique. The modified chitosan hydrogel, Cts-SC NPs, was characterized by FTIR, TEM, XRD, TGA, DSC and SEM. The adsorption efficiency of Cts-SC NPs for metal ions Hg2+, Ni2+ and Co2+ from aqueous solution was evaluated. The effects of various parameters such as contact time, pH and initial metal ions concentration were investigated. Adsorption isotherm data were fitted using different two-parameter models. Modified chitosan hydrogel Cts-SC NPs had remarkable adsorption of Hg2+, Ni2+ and Co2+ ions than chitosan hydrogel Cts-NPs. The antimicrobial activity of Cts-NPs towards the bacteria, Bacillus subtilis, Pseudomonas aeruginosa and fungus Aspergillus flavus was improved by modification with sebacoyl chloride to give Cts-SC NPs.

Synthesis and antimicrobial activity of some new pyrazole, fused pyrazolo[3,4-d]-pyrimidine and pyrazolo[4,3-e][1,2,4]-triazolo[1,5-c]pyrimidine derivatives.

Hydrazonyl bromides 2a,b reacted with active methylene compounds (dibenzoylmethane, acetylacetone, ethyl acetoacetate, phenacyl cyanide, acetoacetanilide, ethyl cyanoacetate, cyanoacetamide and malononitrile) to afford the corresponding 1,3,4,5- tetrasubstituted pyrazole derivatives 5-12a,b. Reaction of 12a,b with formamide, formic acid and triethyl orthoformate give the pyrazolo[3,4-d]pyrimidine, pyrazolo[3,4- d]pyrimidin-4(3H)one and 5-ethoxymethylene-aminopyrazole-4-carbo-nitrile derivatives 13-15a,b, respectively. Compounds 15 a,b reacted with benzhydrazide and hydrazine hydrate to afford pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine and [4-iminopyrazolo- [3,4-d]pyrimidin-5-yl]amine derivatives 16 a,b and 17 a,b. Reactions of compounds 17 a,b with triethyl orthoformate and carbon disulfide give the corresponding pyrazolo[4,3-e]- [1,2,4]triazolo[1,5-c]pyrimidine derivatives 18a,b and 19 a,b, respectively.

Synthesis and biological activity of some new pyrazoline and pyrrolo[3,4-c]pyrazole-4,6-dione derivatives: reaction of nitrilimines with some dipolarophiles.

Several 1,3-diaryl-5-(cyano-, aminocarbonyl- and ethoxycarbonyl-)-2-pyrazoline, pyrrolo[3,4-c]pyrazole-4,6-dione and 1,3,4,5-tetraaryl-2-pyrazoline derivatives were prepared by the reaction of nitrilimine with different dipolarophilic reagents. The new compounds were characterized using IR, (1)H-NMR, (13)C-NMR and mass spectra. Biological screening of some compounds is reported.