The aim of the present study was to isolate antibacterial compound from Streptomyces sp. VITMK1 isolated from mangrove soil of Pichavaram, Tamil Nadu, India. A total of 31 actinomycetes isolates were isolated from soil samples collected at the mangrove region. Actinomycetes isolates were screened for antibacterial activity by well diffusion method. The potential isolate was identified and characterized using morphological, biochemical and molecular taxonomic methods. The partial 16S r-RNA gene sequence of the potential isolate was submitted to GenBank under the accession number KF493733. The isolate was mass cultured on Tryptone Yeast Extract (ISP 1) medium followed by solvent extraction using ethyl acetate (EA). The EA extract showed antibacterial activity with a maximum zone of inhibition against Proteusvulgaris (23 mm), Salmonellaparatyphi (21 mm), Staphylococcusaureus (20 mm) and Bacilluscereus (20 mm). The EA extract was purified using silica gel column chromatography using chloroform and EA (9:1 v/v) as solvent system and the active fraction was subjected to compound identification using spectral techniques such as fourier transform infrared spectroscopy, gas chromatography–mass spectrometry and hydrogen and carbon nuclear magnetic resonance spectroscopy. The compound was identified as Pyrrolo [1, 2-A] pyrazine-1, 4-dione, hexahydro-3-(2-methylpropyl) with a molecular weight of 210 kDa. The extracted compound showed high antibacterial activity. © 2015, The National Academy of Sciences, India.