 The provisional naming was "nimbin" (sulphur-free crystalline product with melting point at 205 °C, empirical composition C7H10O2), "nimbinin" (with similar principle, melting at 192 °C), and "nimbidin" (cream-coloured containing amorphous sulphur, melting at 90–100 °C).Siddiqui identified "nimbidin" as the main active antibacterial ingredient, and the highest yielding bitter component in the neem oil.These compounds are stable and found in substantial quantities in the Neem.