Polyethylene Glycol-400 Prompted an Efficient Synthesis of Thienyl Pyrazolo[ 1,5-a] Pyrimidines as Microbial Inhibitors.

AIMS: The aim of this present work was to design and establish an efficient synthesis of new thienyl pyrazolo[1,5-a] pyrimidines using an environmentally friendly reaction solvent. Further, the newly synthesized compounds were evaluated for antimicrobial activity. MATERIALS AND METHODS: A series of thienyl pyrazolo[1,5-a] pyrimidines have been synthesized by the condensation reaction of 4-(4'-chloro-phenylazo)-5-amino pyrazole with α, ß- unsaturated carbonyl composites (chalcones) using NaOH in polyethylene glycol- 400 as a green reaction solvent. The dissemination technique recommended by the National Clinical Laboratory Standards Committee was used to study the antimicrobial activities of synthesized compounds. RESULTS AND DISCUSSION: Polyethylene glycol-400 prompting an efficient synthesis of thienyl pyrazolo[1,5-a] pyrimidines have been discussed. Excellent yields of the products were obtained in a shorter reaction time using PEG 400 as a green reaction solvent. The reaction solvent was recovered and reused without the loss of its activity. The synthesized compounds have shown interesting antibacterial activity. Hydroxyl and halo substitution with thienyl moiety emerged as an active antibacterial and antifungal study. CONCLUSION: The advantage of this methodology is that it incorporates the green method, has excellent yields, easy workup, avoids toxic solvents, and an expensive catalyst. The new dimension pyrazolo[1,5-a] pyrimidine derivatives with thienyl moiety exhibit promising anti-microbial activity.

Trisubstituted thiophene analogues of 1-thiazolyl-2-pyrazoline, super oxidase inhibitors and free radical scavengers.

Xanthine oxidase (XO) generates superoxide anions and H(2)O(2) for the self-defence system of organism. Abnormal production of this superoxide's (reactive oxygen species) is responsible for a number of complications including inflammation, metabolic disorder, cellular aging, reperfusion damage, atherosclerosis and carcinogenesis. Series of novel trisubstituted thiophenyl-1-thiazolyl-2-pyrazoline libraries are synthesized containing 2,5-dichloro thiophene, 5-chloro-2-(benzylthio) thiophene and 5-chlorothiophene-2-sulphonamide, from chalcones in PEG-400 as green solvent. Superoxide (XO) inhibitory and free radical scavenging activities were also figured out with molecular modeling analysis, bearing in mind their possible future for super oxide inhibitor (Gout) therapeutics, compound 3k shows interesting superoxide inhibitory and free radical scavenger activity with IC(50)=6.2 µM, in comparison with allopurinol.

Poly(ethylene glycol) (PEG-400) as an alternative reaction solvent for the synthesis of some new 1-(4-(4'-chlorophenyl)-2-thiazolyl)-3-aryl-5-(2-butyl-4-chloro-1H-imidazol-5yl)-2-pyrazolines and their in vitro antimicrobial evaluation.

Several 1-(4-(4'-chlorophenyl)-2-thiazolyl)-3-aryl-5-(2-butyl-4-chloro-1H-imidazol-5yl)-2-pyrazoline derivatives were prepared by the base catalyzed treatment of appropriate chalcones with 4-(4'-chlorophenyl)-2-hydrazino-thiazole in poly (ethylene glycol) (PEG-400) as an alternative reaction solvent. All the synthesized compounds were tested for their antimicrobial activities against Escherichia coli (MTCC 2939), Salmonella typhi (MTCC 98), Staphylococcus aureus (MTCC 96), Bacillus subtilis (MTCC 441), Aspergillus niger (MTCC 281), Trichoderma viridae (MTCC 167), Penicillium chrysogenum (MTCC 160), Fusarium moniliforme (MTCC 156) and Candida albicans (MTCC 183). Most of the compounds showed potent antibacterial and antifungal activity.