Design, Molecular docking, Synthesis and Biological evaluation of 5, 7 dimethyl pyrido(2, 3-d)pyrimidin-4-one and 4,5 dihydro pyrazolo (3, 4-d) pyrimidines for cytotoxic activity

The fused pyrimidine derivatives are potent tyrosine kinase and thymidylate synthase inhibitors. The compound 3-(4-sulphonyl amino)-2-methyl thio-6-phenyl azo-5, 7-dimethyl pyrido(2,3-d)pyrimidin-4-one was synthesized from Ethyl 2-amino-4,6-dimethylpyridine-3-carboxylate, benzene diazonium chloride, benzene sulphonyl amino isothiocyanate in subsequent reactions. 1-(1, 3-benzothiazol-2-yl)-3-methyl-4-phenyl-1H-pyrazolo[3,4-d]pyrimidines were synthesized from 1, 3-benzothiazole, 2-thiol, Hydrazine Hydrate, 2-hydrazinyl-1, 3-benzothiazole and aldehydes in subsequent reactions. Twenty-five derivatives pyrimidine scaffolds were designed and performed molecular docking studies for the ability to inhibit the target protein using molecular docking simulation, selective compounds were synthesized and characterized by spectral methods. All the synthesized compounds evaluated for their antioxidant activity and MTT assay exhibited compounds 13c, 13e and 14d can be potential anticancer candidates against MCF-7, Hep G2 and Hela cell lines respectively. Based on all the studies conclude that good agreement was observed between the top-ranked docking scores and top experimental inhibitors when compared with standards ascorbic acid and imatinib. Hence, the compounds could be considered as new anticancer hits for further lead optimization.

The Effect of Fiber Chemical Treatment on Chemical Resistance Behavior of Jute Polyethylene Composites for Storage Tank Application

The jute polyethylene composites were developed using the hot-press technique with different fiber weight ratios. Due to the hydrophilic nature of fiber, it exhibited poor interfacial interaction to hydrophobic polymer matrix. In order to enhance the interfacial interaction between fiber and polymer, the benzene diazonium salt (BDS), propionic anhydride (PA), and 3-isocyanatopropyl triethoxysilane (silane) treated jute were used for the manufacturing of composites in this study. The chemical resistance tests of prepared composites were performed in order to probe whether these are resistant to various chemicals such as: acids, alkalis, and solvents. The effect of chemical treatments of the composites have been investigated. It was observed that the fabricated composites were resistant to all chemicals except carbon tetrachloride. The treated jute composites showed higher chemical resistance than raw jute composite and silane treated jute composite yield the highest resistance which can be suggested for making the water and chemical storage tanks.

A novel trans-amination process in 3-arylamino- 5,5-dimethylcyclohex-2-en-1-one with nucleophiles and antimicrobial activity of selected products

Reaction of dimedone with arylamines afforded the respective enaminones. Some N-acetyl derivatives were prepared. The reaction of enaminones with hydroxylamine was found to be dependent on the nature of the arylamine moiety and the molar ratio of hydroxylamine to give the mono-, di- or tri-oximes. Cyclization of the trioxime by acetic anhydride gave dihydrobenzo[c][1,2,5]oxadiazol-4(5H)-one-5-O-acetyloxime. Coupling of the synthesized enaminones with benzene diazonium chloride gave 2,4-bis-phenylhydrazones or a mixture of 2-mono hydrazones and bis-hydrazones depending on the nature of the arylamine moiety. Trans-amination of the arylamine of the bis hydrazones with hydroxylamine gave the same1,3-bis oxime derivative. The structures of the synthesized compounds were confirmed by IR, 1HNMR, 13C NMR spectra. The antimicrobial activity of some selected products showed promising results.

Rapid in Situ Generation of Benzene Diazonium Ions under Basic Aqueous Conditions from Bench-Stable Triazabutadienes

Aryl diazonium ions are useful across a range of chemical/biochemical areas. These species are generally made using strongly acidic conditions, which can be detrimental to acid-sensitive functional groups. The ability to generate benzene diazonium ions under basic aqueous conditions is reported herein along with newfound understanding on the aqueous reactivity of solubilized triazabutadienes whereby π-interactions appear to confer a large degree of stability.

Synthesis and antitumor activity of some novel thiophene, pyrimidine, coumarin, pyrazole and pyridine derivatives

2-Cyano-N-(thiazol-2-yl) acetamide (2a) and 2-cyano-N-(oxazol- 2-yl) acetamide (2b) were obtained via the reaction of ethyl cyanoacetate with either 2-aminothiazole (1a) or 2-aminooxazole (1b). The formed products were directed toward the reaction with cyclopentanone and elemental sulfur in the presence of triethylamine to give cyclopenta[b]thiophene derivatives (3a,b). The latter products were reacted with either ethyl cyanoacetate or malononitrile to form compounds 4a,b and 5a,b, respectively. Compounds 4a,b were aimed at synthesizing some heterocyclic compounds; thus internal cyclization reactions were introduced to form compounds 6a,b. Also, compounds 4a,b reacted with salicylaldehyde, hydrazine derivatives and either urea or thiourea to produce coumarin derivatives (7a,b), pyrazole derivatives (8a-d) and pyrimidine derivatives (9a-d), respectively. Reaction of either benzaldehyde or benzene diazonium chloride (11) with compounds 4a,b afforded compounds 10a,b and 12a,b, respectively. On the other hand, compounds 5a,b underwent internal cyclization to form pyrimidine derivatives 13a,b. Also, when compounds 5a,b reacted with either ethyl cyanoacetate or malononitrile, they gave pyridine derivatives (15a-d) through the formation of intermediates (14a-d). Finally, formation of fused pyrimidine derivatives (17a,b) was achieved through the reaction of compounds 5a,b and salicylaldehyde applying two different pathways. The first pathway used a catalytic amount of piperidine to form compounds 16a,b; the latter products underwent cyclization to give compounds 17a,b. The second pathway, using a catalytic amount of sodium ethoxide solution directly in one step, afforded compounds 17a,b. Structures of the newly synthesized compounds were established using IR, 1H NMR, 13C NMR and mass spectrometry and their antitumor activity was investigated. Some of these compounds showed promising inhibitory effects on three different cell lines. However, fused pyrimidine acetonitrile derivatives 6a and 6b exerted the highest inhibitory effect, comparable to that of doxorubicin.

STUDY OF THE EFFECT OF CHEMICAL TREATMENTS ON THE TENSILE BEHAVIOUR OF ABACA FIBER REINFORCED POLYPROPYLENE COMPOSITES

Abaca fibers were subjected to different chemical treatments like alkali treatment, permanganate treatment, acrylation & benzene diazonium chloride treatment and these chemically treated fibers were used as reinforcements in the preparation of polypropylene composites by hot compression moulding method. Various composites were fabricated with different fiber loadings of 20%, 30%, 40%, 50%, 60%, and 70%. Abaca composites with 40% fiber loadings were found to have optimum properties when tensile tests were carried out and the study also revealed that treated composites were found to have improved tensile properties when compared to untreated composites. Among all the treatments carried out benzene diazonium chloride treated abaca fiber reinforced polypropylene composites showed higher tensile strength. These composites showed 82.38% increase in tensile strength when compared to untreated composites for 40% fiber loading.