The Schiff's bases 3a–3h were synthesized by reacting substituted/unsubstituted aromatic aldehydes 2a–2h with 1-(2-aminoethyl)-piperazine 1. A series of novel aryl-3-(2-piperazin-1-ylethyl)-1,3-thiazolidin-4-one 4a–4h and 3-chloro-1-{2-[4-(chloroacetyl)piperazin-1 yl]ethyl}-4-arylazetidin-2-one 5a–5h were synthesized from the Schiff's bases of 1-(2-aminoethyl)-piperazine 3a– 3h. The structures of synthesized compounds were confirmed by analytical (C, H, and N) and spectral (FT-IR, 1 H NMR, 13C NMR, and Mass) data. The compounds 4a–4h and 5a–5h were screened for antimicrobial activity. The compounds 4a, 4d, 4f, 4g, 5a, 5d, 5f, and 5g exhibited substantially significant antibacterial as well as antifungal activity.