Designing and Synthesis of Flavonoids Derivatives and Screening of their Antimicrobial Activity

Abstract

Antimicrobial drugs either kill microbes (microbicidal) or prevent the growth of microbes (microbistatic). The streptococcus mutans is a bacteria that found in the human mouth cavity. This bacterial strain produces plaque and acids that break down tooth enamel and cause dental caries. Gram positive cocci, facultatively anaerobic bacteria that forms rod-like chains. the chemical reaction of 2- hydroxyacetophenones with aromatic acylchloride occurs to form 1,3-diketones. This rearrangement reaction proceeds via enolate formation followed by acyl transfer. Then it cyclises into flavone.13 As the same of above scheme can be worked out as 2- Methoxybenzoyl Chloride is prepared by reaction of 2- methoxybenzoic acid with Thionyl chloride and DMF. 2-Methoxybenzoyl Chloride then added to mixture of 2- hydroxyacetophenone and pyridine, 2-[(2-Methoxybenzoyl)oxy]acetophenone thus obtained is treated with pyridine and KOH which gives1-(2-Hydroxyphenyl)-3-(2- methoxyphenyl)-propan1,3-dione. The result of study indicated that C5 [1-(2- hydroxyphenyl)-5-phenylpenta-2,4-dien-1-one]; is only inactive against Streptococcus mutans. All 3-hydroxyflavone derivatives exhibited their MIC to be in range of 250-125 µg/ml., 2,3-dihydroflavan-3-ol derivatives exhibited their MIC to be in range of 1000- 500 µg/ml. The chalcone derivatives exhibited their MIC to be at 250 µg/ml. Keywords: Streptococcus mutans, flavonoids derivatives, MIC, 2,3-dihydroflavan-3-ol.