Background: An economical plant regeneration was established for Caesalpinia bonducella by culturing immature flower buds and phytoconstituents such as β-Sitosterol (LC3) and methyl (4E)-5-(2-[(1E)-buta-1,3-dien-1-yl]-4,6-dihydroxyphenyl) pent-4-enoate (SC2) were isolated from its extracts and the isolated phytoconstituents were tested against Leptospira interrogans. Objectives: The aim of the study is to establish the C. bonducella through tissue culture technique and to investigate the antileptospiral activity through computational and in vitro screening. Materials and Methods: Morphogenic calli were initiated from 96% of immature flower buds on MS medium supplemented with 2, 4 D (2, 4-Dichlorophenoxyacetic acid) 2.0 mg/l and 6-Benzylaminopurine (BAP) 0.5 mg/l. The calli formed were excised and subcultured on MS medium. Extreme percentage organogenesis (84%) and average shoots per culture were determined on MS medium fortified with 3.0 mg/l BAP and 0.5 mg/l indole-3-butyric acid (IBA). The addition of IBA in ½ MS medium favored the development of recovered shoots. Out of 30 shoots transferred to soil, 27 survived once acclimated. The isolated compounds were selected for in vitro and in silico screening. The primary pharmacological assay for leptospirosis was carried out by test tube dilution and microdilution technique and the computational screening was done using molecular docking. Results: The phytoconstituents obtained from the medicinal plant showed promising results in both in vitro and in silico antileptospiral activity. Conclusion: The LC3 and SC2 compounds isolated from C. bonducella were evaluated on Gram-negative bacteria L. interrogans. The assay and molecular docking studies revealed the efficacy of phytocomponents of C. bonducella as traditional medicine which has an ability to cure bacterial diseases.