Leaves maily yield quercetin (flavonoid) and nimbosterol (β- sitosterol) as well as number of liminoids (nimbin and its derivatives). Quercetin (a polyphenolic flavonoid) is known to have antibacterial and antifungal properties. This may perhaps account for the curative properties of leaves for sores and scabies. Limonoids like nimocinolide and isonimocinolide affect fecundity in house flies (Musca domestica) at a dose ranging between 100 and 500 ppm. They also show mutagenic properties in mosquitoes (Aedes aegypti) producing intermediates. Fresh matured leaves yield an odorous viscous essential oil, which exhibits antifungal activity against fungi (Trichophyton mentagrophytes) in vitro. White crystalline flakes obtained from petroleum ether extract of leaves consisting of a mixture of C 14, C 24, C 31 alkanes were found to exceed or equal the lavicidal activity of pyrethrum extract.