Organic Chemistry: Current Research
Open Access
ISSN: 2161-0401
+44 1478 350008
ISSN: 2161-0401
+44 1478 350008
Lucian M Birsa, Laura G Sarbu and Lucian G Bahrin
Alexandru Ioan Cuza University of Iasi, Romania
Posters & Accepted Abstracts: Organic Chem Curr Res
The synthesis of new 3-dithiocarbamic flavonoids has been accomplished by the reaction of the corresponding 2-hydroxyaryl dithiocarbamates with aminals. These flavonoids were obtained as a mixture of diastereoisomers, the anti isomer being the major one. The heterocyclization of these compounds provided a little known class of tricyclic flavonoids bearing a 1,3-dithiolium-2-yl ring fused at the 3,4-carbon positions of the benzopyran moiety. Sulfur containing flavanones and tricyclic flavonoids were tested for antibacterial activity against Staphylococcus aureus ATCC 25923 (Gram-positive) and Escherichia coli ATCC 25922 (Gram-negative), using disc diffusion assay with gentamicin as reference and minimum inhibitory concentrations were determined where activity was found present.1-4 While the tested flavanones did not yield the desired results, good antibacterial activities were recorded for the tricyclic flavonoids. The introduction of the 1,3-dithiolium cation produced results comparable to those of gentamicin and in some cases, MIC values were less than 1μg/ml. The ion-dissociation vs. formation of a tight ionpair appears to be of significant importance on how cationic tricyclic flavonoids interact with bacteria. The major component of bacterial cell wall is represented by negatively charged phosphatidylethanolamine (70%). Thus, the positively charged 1,3-dithiolium flavonoids target the oppositely charged biological structures such as cell walls of microorganisms which leads to the leakage of intracellular substances.5
Recent Publications
1. Bahrin LG, Jones PG, Hopf H (2012) Beilstein J Org Chem 8: 1999-2003.
2. Bahrin LG, Apostu MO, Birsa ML, Stefan M (2014) Bioorg. Med. Chem. Lett 24: 2315-2318.
3. Bahrin LG, Hopf H, Jones PG, Sarbu LG, Babii C, Mihai AC, Stefan M, Birsa ML (2016) Beilstein J Org Chem 12: 1065-1071.
4. Bahrin LG, Sarbu LG, Hopf H, Jones PG, Babii C, Stefan M, Birsa ML (2016) Bioorg Med Chem 24: 3166-3173.
5. Babii C, Bahrin LG, Neagu A, Gostin I, Mihasan M, Birsa ML, Stefan M (2016) J Appl Microbiology 120: 630- 637.
Lucian M Birsa is currently a Professor in the Department of Chemistry at the Alexandru Ioan Cuza University of Iasi, Romania. He received a Bachelor of Science degree in Chemistry from the same university in 1995. He joined the master program at Alexandru Ioan Cuza University of Iasi in 1995, and in 2000 was awarded a PhD. degree in Organic Chemistry. From 2000 to 2002, he was a postdoctoral fellow under the mentorship of Professor Samuel Braverman at Bar-Ilan University, Israel. In 2003 he was selected as a member of the Alexander von Humboldt Foundation, working with Professor Henning Hopf in TU Braunschweig - Germany. Since then numerous return fellowships were granted by the Alexander von Humboldt Foundation.