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Updated: Jan 27, 2026

Synthesis of Masarimycin, a Small Molecule Inhibitor of Gram-Positive Bacterial Growth
Published on: January 7, 2022
A preliminary study on quinazolinylaminobenzoyl monopeptide esters as effective Gram-positive bacteriostatic agents
Nikil Purushotham1, Boja Poojary1, Vaishali Rai2
1Department of Chemistry, Mangalore University, Mangalagangothri-574 199, Karnataka, India.
Aim:
To investigate a novel series of quinazoline monopeptide esters for the in vitro antibacterial activity.
Methodology/Results:
The compounds were synthesized via one-pot Dimroth rearrangement of suitable formamidine intermediates with 3-aminobenzoic acid, followed by coupling the resulting acids with amino acid esters and screening for their antibacterial activity by broth dilution method. The compounds 5a, 5b, 5c, 5g, 5i and 5j showed promising activity against the Gram-positive bacteria, 5c and 5g being the most potent against Enterococcus faecalis and Staphylococcus aureus, respectively, with a minimal inhibitory concentration of 0.51 μM. The percentage hemolysis of the compounds ranged from 2.79 to 12.92 at a concentration of 100 μg/ml. The molecular docking studies revealed their GlmU inhibitory action.
Conclusion:
The compounds 5a and 5g emerged as antibacterial hits.
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