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The synthesis and characterization of two distinct novel series of compounds, [II]n and [V]n, containing 1,3,4-thiadiazole units, were studied in this work. The central core of the first series is phenyl, whereas the central core of the second series is OCH2CH2O. FTIR,1HNMR,13CNMR, and mass spectroscopy are used to characterize the materials used in this investigation. Liquid crystalline properties were confirmed by the use of differential scanning calorimeter (DSC) and hot-stage polarizing optical microscopy (POM). While other compounds showed no liquid crystalline behavior, the compounds [II]3–[II]6, [V]1and [V]n showed enantiotropic nematic and smectic phases. [ABSTRACT FROM AUTHOR]

This work includes the synthesis of new ester compounds containing two 1,3,4- oxadiazole rings, 15a-c and 16a-c. This was done over seven steps, starting with pacetamido-phenol 1 and 2-mercaptobenzoimidazole 2. The structure of the products was determined using FT-IR, ¹H NMR, and mass spectroscopy. The evaluation of the antimicrobial activities of some prepared compounds was achieved against four types of bacteria (two types of gram-positive bacteria; Staphylococcus aureus and Bacillus subtilis, and two types of gram-negative bacteria, Pseudomonas aeruginosa and E. Coli), as well as against one types of fungus (C. albino). The results show moderate activit against the study bacteria, and the theoretical analysis of the toxicity demonstrates non-toxicity with acute oral human toxicity. Also, the toxicity of these compounds in rats was weak. A molecular modelling study explains that these compounds possess good binding with lung cancer proteins. [ABSTRACT FROM AUTHOR]

The organic compound imidazole has the chemical formula C3N2H4. Numerous significant biological compounds contain imidazole. The amino acid histidine is the most prevalent. The substituted imidazole derivatives have great potential for treating a variety of systemic fungi infections. Thiourea is an organosulfur compound with the formula SC(NH2)2. It is a reagent in organic synthesis. In this paper, some new imidazole and thiourea derivatives are synthesized, characterized, and studied for their biological activity. These new compounds were synthesized from the starting material terephthalic acid, which was transformed to corresponding ester [I] by the refluxing of diacid with methanol in the presence of H2SO4 as a catalyst, compound [I] condensation with hydrazine hydrate 80% to yielded acid hydrazide [II], which was refluxed with 2 moles of various aromatic aldehydes in the presence of few drops of glacial acetic acid as a catalyst to yielded Schiff bases [IIIa-d]. Refluxing of chosen derivative [IIIa-d] with acetyl chloride in dry benzene gave new acetyl compounds [IVa-a] which were reacted with thiourea and anhydrous sodium carbonate with acetone as a solvent to give new thiourea derivatives [Va-d]. Compounds [Va-d] were used to synthesize new imidazole derivatives [VIa-d] by the reaction of appropriate compound [Va-d] with 2 moles of benzoin in dry DMF under cyclization reaction. FTIR, HNMR, and mass spectroscopy are used to characterize the synthesized compounds. [ABSTRACT FROM AUTHOR]

The work involves synthesis of new compounds derived from 2-substituted-3-thio- acetohydrazide-1,2,4-triazin. The subsituted hydrazine thiocarbothioamide [IV] was obtained via reaction of hydrazide compound [III] with ammonium thiocyanate and HCl. The cyclization of compound [IV] in 4% NaOH led to formation 1,2,4-triazoles [V], which were refluxed with chloro-ethylacetate in ethanol and sodium acetate to give compound [VI]. Condensation of ester-compound [VI] with hydrazine (80%) led to formation new hydrazide compounds [VII]. Ring closure reaction of compound [VII] with 4-aminbenzoic acid in POCl3 give 1,3,4-oxadiazoles [VIII]. Compound [VIII] was reacted with sub. benzaldehyde to form compounds of Schiff bases [IX]a-d. The synthesized compounds were diagnosed via IR, Mass and ¹HNMR spectral data. Many of synthesized compounds were examined against activity of antibacterial: gram (+) (Bacillus subtitis, staphylococcus aureus) and gram (-): (E.coli bacteria) and candida tropicalis fungial. To ensure the safety of the synthesis compounds the toxicity was examined. [ABSTRACT FROM AUTHOR]

A research include of synthesized five member ring, which has been synthesized by condensation of 2-(1-(4- hydroxyphenyl) ethylidene)hydrazine-1-carbothioamide[I] with α-chloro ethylacetate in sodium acetate (fused) to form ethyl 2-(4-(1-((4-oxo-2-thioxopyrrolidin-3-ylidene)hydrazono) ethyl)phenoxy)acetate [II]. After that reacted [II]with hydrazine hydrate to resulting compound [III]. Compound [III] was refluxed with 4-aminobenzoicacid in excess of phosphorus oxy chloride give compound [IV],the later compound [IV] interact with acetyl acetone or ethylacetoacetate give to pyrazole and pyrazoline derivatives[V],[VI]. While when reacted with different aromatic aldehydes and one ketone consistence Schiff base derivatives [VII]a-e . The FTIR and 1HNMR were used for characterized the synthesized compounds, the synthesized derivatives have been screened for their two species of bacteria were used in this study as tested organisms. These are Escherichia Coli (Gram negative) and staphylococcus (Gram positive). [ABSTRACT FROM AUTHOR]

A novel series of chitosan derivatives were synthesized via reaction of chitosan with carbonyl compounds and grafted it’s by with different amine compounds substituted hydrogen. The produced polymers were characterized by different analyses FTIR, 1HCNMR, XRD, DSC and TGA. Solubility in water as well as many solvent was investigated, antibacterial activity of chitosan and its derivatives against two types of bacteria E. coli and S. aureus was also investigated. The results showed that derivatives sort of have antibacterial activities against Esherichia coli (Gram negative) better than chitosan whilst compound IX has better antibacterial against Staphylococcus aureus (Gram positive). SEM analysis showed that increase of surface roughness with modification. [ABSTRACT FROM AUTHOR]

The compound [G1] was prepared from the reaction of thiosemicarbazide with para-hydroxyphenylmethyl ketone in ethanol as a solvent. Then by sequence reactions prepared [G2] and [G3] compounds. The compound [G4] reaction with ethyl acetoacetoneto synthesized compound [G6] and acetyl acetone to synthesized compound [G5]. Reaction the [G3] with two different types of aldehydes in the present of pipredine to form new alkenes compounds [G7]and [G8]. The compound [G3] reacted with hydrazine hydrate to formation[G4] with present the hydrazine hydrade 80% in (10) ml of absolute ethanol. Latter the compound [G4]reacted with different aldehydes with present the glacial acetic acid and the solvent was ethanol to formed the Schiff bases compounds[G9] and [G10]. All the prepared compounds were characterized by FT-IR, 1H-NMR spectra, also biologically activity evaluated, the synthesized derivatives have been screened for their two species of bacteria were used in this study as tested organisms. These are Escherichia Coli (Gram negative) and staphylococcus (Gram positive). [ABSTRACT FROM AUTHOR]

Two series of bent and liner core mesogen containing 1,2,4-traizole ring [VI]a, g and series were synthesized by many steps starting from esterification of isophthalic acid and terephathalic acid with methanol to yield diester compound [I]a, b which was converted to their acid hydrazide [II]a, b and the acid hydrazide reacted with ammonium thiocyanate or diester reacted with thiosemicarbazide to yield compounds [III]a, b. Then cyclization by 4% NaOH to yielded 1,2,4 traizole-3-thiol compounds [IV]a, b, afterword adding hydrazine hydrate to yield compounds [V]a,b. These compounds condensated with different substituted aldehyde to give new Schiff bases[VI]a,b,[VII]a,b. Also, reaction acid hydrazide [II]a,b with aldehyde [VII] to yielded Schiff bases [IX]a,b and then reaction with thioglycolic acid to yielded thiazolidinone [X]a,b in addition to synthesized Schiff bases [XI]a,b from reaction compounds [V]a,b with aldehyde [VIII]. The synthesized compounds were characterized by melting points, FT-IR, 1H-NMR and Mass spectroscopy (some of them). The liquid crystalline properties were studied by hot stage polarizing optical microscopy(POM) and differential scanning calorimetry DSC. [ABSTRACT FROM AUTHOR]

A series of amic acid derivatives of mefenamic acid were synthesized with the aim of inhibitting topical gastrointestinal toxicity of mefenamic acid. The key intermediate amic acid (III) was prepared from the reaction of acid hydrazid of mefenamic acid(II) with phthalic anhydrides in dry actone. The new type of imide compound (IV) was dehydrated the amic acid(III) with acetic anhydrous and sodium acetate. The esterification of hydroxyl groups of amic acid (III) produce corresponding ester(V), which was condensed with hydrazine hydrate to give acid hydrazide (VI), then the later compound reacted with syringaldehyde in dry benzene to yield new schiff base (VII). The new derivatives containing heterocyclic unit (VIII)- (X), four and five, member ring were successfully formed such as azetidin-2-one, thiazolidin-4-one, and,imidazolidin-4-one. The structures of the synthesized compounds were confirmed using FTIR, 1HNMR, Mass and CHN-S. The antibacterial activities of some synthesized compounds were screened and showed a highest or low inhibition against Staph.aureus (G+), Bacillus subtilisa (G+), Klebsiella pneumoniae (G-), and E.coli (G-). Also, The cytotoxic effect of different concentrations of some the synthesized compounds was tested against MCF-7 cell line (human breast carcinoma cells) and positive results were obtained for some of them, which encouraged us to study the toxicity using living organisms (mice) to evaluate its acute toxicity and proved the resules of non-toxicity of the derivatives. [ABSTRACT FROM AUTHOR]

The compounds 3-[4-(4-methoxybenzoyloxy) benzylideneamino]-2-thioxo-imidazolidine-4-one(3)aand 4-(1-(5-oxo-2-thioxoimidazolidin-1-ylimino)ethyl)phenyl acetate(3)b were prepared from the reaction of aromatic aldehyde or ketone(1)a,bwith thiosemicarbazide to give aryl thiosemicarbazones(2)a,b ,followed by cyclization with ethylchloroacetate in the presence of fused sodium acetate. Treatment the compounds(3)a,bwith 4- hydroxybenzenediazoniumchloride yielded the correspondings4-((4-((4-hydroxyphenyl)diazenyl)-5-oxo-2- thioxoimidazolidin-1-ylimino)methyl)phenyl 4-methoxybenzoate(4)aand4-(1-(4-((4-hydroxyphenyl)diazenyl)-5-oxo-2- thioxoimidazolidin-1-ylimino)ethyl)phenyl acetate(4)b. The new 2-thioxo-imidazolidin-4-one with esters (5-7)a,b synthesized by reacting (4)a,b with different acid chlorides. The synthesized compounds were characterized by IRand1HNMR spectra (of some of them) in order to elucidatetheir structures. [ABSTRACT FROM AUTHOR]

Some new 2,5-disubsituted-1,3,4-oxadiazole derivatives with azo group were synthesized by known reactions sequence. The structure of the synthesized compounds were confirmed by physical and spectral means. [ABSTRACT FROM AUTHOR]