Testing enabling techniques for olefin metathesis reactions of lipophilic substrates in water as a diluent.

Olefin metathesis reactions of diverse polyfunctional substrates were conducted in water emulsions using two hydrophobic ruthenium catalysts in the presence of air. Instead of using surfactants to increase the efficiency of the metathesis reaction in water, ultrasound and microwave techniques were tested on a small-scale reaction, whereas conventional heating and mechanical stirring were effective enough to provide high conversion and selectivity on a larger scale. The developed conditions extend known protocols for the aqueous metathesis methodology, utilizing relatively low catalyst loadings and allowing for simple product isolation and purification. The established synthetic protocol was successfully adopted in the large-scale synthesis of a pharmaceutically related product - sildenafil (Viagra) derivative.

Synthesis and biological screening of novel 2-morpholinoquinoline nucleus clubbed with 1,2,4-oxadiazole motifs.

Novel series of 2-morpholinoquinoline scaffolds (6a-n), containing the 1,2,4-oxadiazole and moiety, was designed and synthesized in good yield (76-86%). The synthesized compounds were screened for their preliminary in vitro antimicrobial activity against a panel of pathogenic strains of bacteria and fungi. Molecular docking and pharmacokinetic study were carried out for the prepared compounds. The cytotoxicity of the synthesized compounds was tested at different concentrations using bioassay of S. pombe cells at the cellular level. The effect of synthesized compounds on the DNA integrity of S. pombe was observed on agarose gel. Compounds 6d, 6e, 6g, 6h, 6j and 6n exhibited excellent antimicrobial potency as compared to the standard drugs (i.e Ampicillin, Norfloxacin, Chloramphenicol, Ciprofloxacin). Compounds 6d, 6e, 6g, 6k and 6n were found to have significant antifungal activity as compared to griseofulvin. Compounds 6f, 6i, 6k, 6l were found very less cytotoxic, while compounds 6d, 6e, 6g, 6h were found to exhibit maximum toxicity. The rest of the synthesized compounds were found to be moderately toxic.

Novel morpholinoquinoline nucleus clubbed with pyrazoline scaffolds: Synthesis, antibacterial, antitubercular and antimalarial activities.

A series of novel morpholinoquinoline based conjugates with pyrazoline moiety were synthesized under microwave irradiation. The newly synthesized compounds were screened for their preliminary in vitro antibacterial activity against a panel of pathogenic strains of bacteria and fungi, antituberculosis activity against Mycobacterium tuberculosis H37Rv and antimalarial activity against Plasmodium falciparum. Most of them exhibited significant antibacterial activity as compared to the first line drugs. Compounds 6a and 9d were found to possess excellent antibacterial activity potency as compared to ampicillin (286 µM), chloramphenicol (154 µM) and ciprofloxacin (150 µM). In antifungal screening, against Candida albicans, compounds 6c, 7c, 8a, 8b, 8c and 9b showed significant activity as compared to griseofulvin (1147 µM). Compounds 8b, 6b, 9d, 6a, 9b, 7b and 8a displayed brilliant activity against P. falciparum strain as compared to chloroquine (IC50 0.062 µM) as well as quinine (IC50 0.826 µM). Compounds 6d, 7b, 8b, 9c and 9d exhibited superior antitubercular activity. Among them 8b was found to be equipotent to rifampicin with 95% inhibition. The cytotoxicity of the synthesized compounds was tested using bioassay of Schizosaccharomyces pombe cells at cellular level.

Design, synthesis and characterization of fluoro substituted novel pyrazolylpyrazolines scaffold and their pharmacological screening.

A novel series of fluoro substituted pyrazolylpyrazolines 7a-l was synthesized in good to excellent yield (77-88%) from pyrazole chalcones 5a-d and substituted phenyl hydrazine hydrochlorides 6a-c under microwave irradiation. The newly synthesized compounds were screened for their preliminary in vitro antibacterial activity against a panel of pathogenic stains of bacteria and fungi, antituberculosis activity against Mycobacterium tuberculosis H37Rv and antimalarial activity against Plasmodium falciparum. Compounds 7a, 7b, 7g, 7h, 7j and 7k displayed excellent activity against P. falciparum stain as compared to quinine IC50 0.268. Good antitubercular activity was exhibited by compounds 7a, 7e, 7h and 7k. Some of them also exhibited superior antibacterial activity as compared to the first line drugs.