Synthesis of some new 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2 H)-pyridazinone derivatives

The present study describes the synthesis of 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone derivatives. The synthesis of the first target compound, 4,5-dihydro-6-(4-methoxy-3-methylphenyl)-3(2H)-pyridazinone(1), was achieved by Friedel-Crafts acylation of o-cresylmethyl ether with succinic anhydride and subsequent cyclization of the intermediary g-keto acid with hydrazine hydrate. Condensation compound 1 with aromatical dehydes in the presence of sodium ethoxide affords the corresponding 4-substituted benzyl pyridazinones(3a-d). The pyridazinone 1 under went dehydrogenation upon treatment with bromine/acetic acid mixture to give (4). Pyridazine (5) has been synthesized upon the reaction of pyridazinone  (1) with 1,3-diphenyl-2-propen-1-one under the Michael addition reaction.  N-dialkylaminomethyl derivatives 6a-b have been obtained from the reaction of pyridazinone 1 with formaldehyde and secondary amine, whereas reaction of 1 with formaldehyde gives N-hydroxymethyl derivative (7). This study also includes the synthesis of the 3-chloro pyridazinone derivative 8 in excellent yield by heating pyridazinone 3b in phosphorus oxychloride. The behaviour of the chloro derivative toward sodium azide, benzyl amine and anthranilic acid was also studied. The proposed structures of the products were confirmed by elemental analysis, spectral data and chemical evidence

Synthesis, biological activity and electron impact of mass spectra of trisubstituted-2-thiohydantoins

3-[1-(2-Hydroxyphenyl)ethylideneamino]-2-thiohydantoin (2) was prepared via cyclization of 2-hydroxyacetophenone thiosemicarbazone (1) with ethyl chloroacetate in the presence of fused sodium acetate. The chemical behaviour of 2 towards acetic anhydride, arenediazonium chloride, aromatic aldehydes and hydrazine hydrate is described. The electron impact ionization mass spectra of compounds 2 and 3 show a strong molecular ion peak and a base peak of m/z 232 resulting from cleavage fragmentation. The molecular ion of compounds 4a,4b, and 8 is a base peak of m/z 353, 387 and 288, respectively.In contrast, compounds 5a and 5b show a base peak at m/z 336 and 370 resulting from fragmentation. Compounds 6a,b and 7a,b give a characteristic fragmentation pattern with a very stable fragment of m/z 326 and 350, respectively. Some of the synthesized compounds also exhibited antimicrobial activities

Reactions of 5-(4-methoxy-3-methylphenyl)-2(3H)-furanone with some electrophilic and nucleophilic reagents

5-(4-Methoxy-3-methylphenyl)-2(3H)-furanone was prepared and reacted with some nucleophilic and electrophilic reagents. The condensation of furanone with aromatic aldehydes or phthalic anhydride yielded the corresponding 3-arylidenefuranone derivatives and phthalide, respectively. While the treatment of furanone with amines in refluxing ethanol led to the formation of amides. The reaction of the amides with thionyl chloride afforded the corresponding isothiazolones. The benzimidazole derivative was prepared via the reaction of the 2(3H)-furanone with o-phenylenediamine in boiling ethanol. However, hydrazine hydrate affected ring opening of furanone to give the corresponding acid hydrazide, which underwent in situ cyclization into the corresponding pyridazinone. The base catalyzed ethanolysis of furanone afforded the corresponding ethyl ester

Correlation between single crystal data and molecular mechanics calculation of 3-(2-hydroxy-phenylimino)-1,3-diphenyl-propan-1-one

The Schiff base 3-(2-hydroxy-phenylimino)-1,3-diphenyl-propan-1-one (L), was prepared and characterized by elemental analysis, IR, 1H NMR and mass spectral techniques. The crystal and molecular structures were determined by using the single crystal X-ray diffraction data. The crystal was triclinic with unit-cell dimensions: a = 9.051(3) Å, b = 10.245(3) Å, c = 11.016(3) Å, α = 69.28(2)°, β = 81.66(2)°, γ = 64.25(2)°, space group is Pī and Z = 2. The structure was refined by least squares method. The single crystal was prepared by supersaturating method using tetramethoxysilane as gelling agent. Energy minimization for locating stable conformations and single point energy calculations for comparing the obtained and calculated conformations of the same molecule were carried out using molecular mechanics method (MM2 force field). The bond lengths and the bond angles were calculated and compared with the values obtained from the single crystal analysis. The obtained results were discussed and evaluated. Generally, the calculated parameters are in good agreement with the corresponding X-ray diffraction values. The obtained results reveal that, the amine-imine tautomerism is more preferable than keto-enol form and the intra-hydrogen bond stabilize the amine-imine tautomerism.

Synthesis and Mass Spectral Fragmentation Patterns of some 2-Thiohydantoin, Salicyladazine and Pyradazine Derivatives

3-[(5-Arylazo-2-hydroxybenzylidene)amino]-2-thiohydantoins 3a-c were prepared via condensation of 5-arylazo-2-hydroxybenzaldehyde 1 with thiosemicarbazide, followed by cyclization of 2 with ethyl chloroacetate. Acetylation of 3 with acetic anhydride yielded the corresponding diacetyl derivatives 6a-c. Hydrazinolysis of compounds 3 and 6 with hydrazine hydrategave the corresponding 5-arylazosalicylaldehydes 5a-c.Ammonolysis of benzoin (7) with ammonia afforded thecorresponding 2,3,5,6-tetraphenyl-1,4-dihydropyradazine (8). Acetylation of compound 8 with acetic anhydride gave the corresponding 1,4-diacetylpyradazine 9. The electron impact ionization mass spectra of the compounds pairs 3a and 6a, 3b and 6b, and 3c and 6c show a base peak of m/z 77, m/z 91 and m/z 111 resulting from fragmentation. The base peak of compounds 5a, 5b and 5c is the molecular ion for all these compounds

Facile Route for Synthesis of Novel Flame Retardant, Reinforcement and Antibacterial Textile Fabrics Coatings

New and innovative textile fabrics coatings were facilely developed. The coating was developed based on synthesis of novel charring and antibacterial organic agent in conjunction with chitosan. N-[2,3-dibromo-4-(4-methoxy-3-methylphenyl)-4-oxobutanoyl]anthranilic acid was synthesized as organic antibacterial, reinforcement, and charring agent (OA) and then, dispersed in chitosan solution followed by coating on textile fabrics using immersion route forming new flame retardant coating layer. The developed organic molecule structure was elucidated using spectroscopic techniques. The mass loadings of developed organic agent dispersed in chitosan solution were varied between 20–60 wt.%. The coated textile fabrics have special surface morphology of fiber shape aligned on textile fibers surface. The thermal stability and charring residues of the coated textile fabrics were enhanced when compared to blank and organic agent free coated samples. Furthermore, the flammability properties were evaluated using LOI (limiting oxygen index) and UL94 tests. Therefore, the coated textile fabrics record significant enhancement in flame retardancy achieving first class flame retardant textile of zero mm/min rate of burning and 23.8% of LOI value compared to 118 mm/min. rate of burning and 18.2% for blank textile, respectively. The tensile strength of the coated textile fabrics was enhanced, achieving 51% improvement as compared to blank sample. Additionally, the developed coating layer significantly inhibited the bacterial growth, recording 18 mm of clear inhibition zone for coated sample when compared to zero for blank and chitosan coated ones