Hydrazonoyl Chlorides as Precursors for Synthesis of Novel Bis-Pyrrole Derivatives

A convenient synthesis of some novel bis-pyrrole derivatives via hydrazonoyl halides is described. Antimicrobial evaluation of some selected examples of the synthesized products was carried out. The bis-pyrrole derivative having chloro substituents showed good activity against all of the used microbes. The molecular docking of the bis-pyrrole derivatives was performed by the Molecular Operating Environment (MOE) program.

Azoles and bis-azoles: synthesis and biological evaluation as antimicrobial and anti-cancer agents

Novel hydrazonoyl halides 3, 5 and bis-hydrazonoyl halides 7, 9 were synthesized. The synthetic utility of bis-hydrazonoyl halide 7 was explored to prepare novel bis-azole 13 with antipyrine moiety. On the other hand, [1,3,4]thiadiazol-2(3H)-ylidene 17 and thiazol-2(3H)-ylidene 21 derivatives, with antipyrine moiety, were prepared from the reaction of 3-mercapto-3-(phenylamino)acrylamide derivative 10 with N-phenyl benzenecarbohydrazonoyl chloride (14) and 3-(2-bromoacetyl)-2H-chromen-2-one (18), respectively. The structures of the isolated products were confirmed by spectral data (IR, (1)H-NMR, (13)C-NMR, MS) and elemental analyses. The anti-cancer activitiy of the synthesized products against the colon carcinoma (HCT) cell line was determined and the results revealed promising activity of compound 3. In addition, the antimicrobial activity of some selected products was evaluated. The results proclaimed that compounds 9, 17, and 21 have high antibacterial activity against Gram-positive bacteria (SA, BS) and Gram-negative bacteria (PA, EC).

Regioselective Synthesis of Some Pyrazole Scaffolds Attached to Benzothiazole and Benzimidazole Moieties

Condensation of 2-(benzothiazol-2-yl)acetonitrile (1) or 2-(1-methyl-1H-benzimidazol-2-yl)acetonitrile (2) with thiophene-2-carbaldehyde afforded the corresponding acrylonitrile derivatives3or4, respectively. The 1,3-dipolar cycloaddition reaction of the acrylonitrile3or4with nitrile-imine6gave novel pyrazole derivatives pendant to benzothiazole and benzimidazole. The pyrazoline derivative7was converted into the corresponding pyrazole derivative11via thermal elimination of hydrogen cyanide upon heating in sodium ethoxide solution. The structures of the synthesized products were confirmed by IR,1H NMR, and mass spectral techniques.

Synthesis and antimicrobial activity of some new thieno[2,3-b]thiophene derivatives

A series of thieno[2,3-b]thiophene moiety-containing bis-cyanopyrazoles 5a–c, bis-aminopyrazole 9 and bis-pyridazine derivatives 11 were synthesized and evaluated in vitro for their antimicrobial potential. The antimicrobial activity of some selected products was evaluated and showed good results. 5,5'-(3,4-Dimethylthieno[2,3-b]thiophene-2,5-diyl)bis(3-acetyl-1-(4-chlorophenyl)-1H-pyrazole-4-carbonitrile) (5d) was found to be more potent than the standard drug amphotericin B against Geotricum candidum and equipotent to amphotericin Bagainst Syncephalastrum racemosum. In addition, it was found to be equipotent to the standard drug Penicillin G against Staphylococcus aureus. Moreover, it was more potent than the standard drug streptomycin against Pseudomonas aeruginosa and Escherichia coli.