[Studies on nitrofuran derivatives. V. Synthesis of [2-(5-nitro-2-furyl) vinyl]-azoles and -azines]

Orthoamide und Iminiumsalze, CVIa. Kondensationsreaktionen von Orthoamiden der Alkincarbonsäuren mit CH-aciden Methylheterocyclen

Orthoamides of alkynecarboxylic acids 10 react with 2-thienyl-acetonitrile under condensation to give ketene aminals. In the reaction of orthoamides 10 with 2-benzimidazolyl-acetonitrile tricyclo[1,2-a]benzimidazol-4-carbonitriles are formed under similar conditions. From 2-methyl-1,3-disubstituted-triazin-2,4-diones and orthoamides 10 the ketene aminals result at room temperature.

Small molecules with antimicrobial activity against E. coli and P. aeruginosa identified by high-throughput screening

BACKGROUND AND PURPOSE

New antimicrobials are needed because of the emergence of organisms that are resistant to available antimicrobials. The purpose of this study was to evaluate a high-throughput screening approach to identify antibacterials against two common disease-causing bacteria, and to determine the frequency, novelty, and potency of compounds with antibacterial activity.

EXPERIMENTAL APPROACH

A high-throughput, turbidometric assay of bacterial growth in a 96-well plate format was used to screen a diverse collection of 150,000 small molecules for antibacterial activity against E. coli and P. aeruginosa. The statistical Z'-factor for the assay was > or = 0.7.

KEY RESULTS

Screening for inhibition of E. coli growth gave a 'hit' rate (> 60% inhibition at 12.5 microM) of 0.025%, which was more than 5-fold reduced for P. aeruginosa. The most potent antibacterials (EC50 < 0.5 microM) were of the nitrofuran class followed by naphthalimide, salicylanilide, bipyridinium and quinoazolinediamine chemical classes. Screening of > 250 analogs of the most potent antibacterial classes established structure-activity data sets.

CONCLUSIONS AND IMPLICATIONS

Our results validate and demonstrate the utility of a growth-based phenotype screen for rapid identification of small-molecule antibacterials. The favourable efficacy and structure-activity data for several of the antibacterial classes suggests their potential development for clinical use.