Antibiotics medication is prescribed against bacterial infections. Several drug molecules are known to possess antimicrobial activity in addition to their known pharmacological actions like antihistamines, tranquilizers, Antihypertensive, antipsychotics and anti-inflammatory agents. In a quest to explore a newer antimicrobial drug, the present study proposes a novel synthetic process for Quinoxaline- 6-Carabaldehyde, expected to exhibit antimicrobial potency may be due to quinoxaline moiety in the core molecule structure. The structure and purity of the synthesized drug was established by spectral and elemental techniques. It was evaluated for antimicrobial potency in vitro and in vivo. The minimum inhibitory concentration (MIC) of the drug against the bacteria was determined by agar and broth dilution methods in vitro. The antibacterial activity was confirmed by animal experiments. Toxicity and protective efficacy of the drug were tested in vivo. The drug inhibited most of the bacterial isolates tested at 25-100 μg/ml concentration and a few were sensitive even at a lower concentration (10 μg/ml). It was found to be bacteriostatic against “Shigella dysenteriae 7”, and bactericidal against “S. aureus NCTC 6571, 8530 and 8531”.When administered to swiss white mice the drug protected the animals challenged with 50 MLD of “Salmonella typhimurium NCTC 74”. The drug showed inhibitory action against several pathogenic bacteria. It also offered significant protection to mice against the bacterial challenge.