A VARIETY of synthetic routes to benzimidazole derivatives have been reported based on different hetero-cyclic rings such as Schiff bases, 2-azetidinone, 4-thiazolidinone and 1,3-oxazepan. Additionally, HOMO-LUMO and vibrational wavenumbers which represents the quantum mechanical calculations of energies, were conducted by Density functional theory (DFT) method at the level of B3LYP with 6-31G(d,p) basis set. FTIR, ¹H NMR spectroscopy and spectral mass spectrometry were used to characterize these compounds; this was followed by measuring the biological activities for gram-negative, gram-positive bacteria and fungi by using diffusion protocol. The outcomes of DFT calculations showed consistency between the experimental values and theoretical of the vibrational and NMR spectroscopy.

Heterocyclic compounds have been used extensively used in pharmaceutical research area due to their effective biological activities. Thiazine, a heterocyclic compound with four carbon atoms, one nitrogen and one sulfur atoms which have promising pharmacological activities that have attracted the attention of scientists and researchers. In this research [3-(4-Amino-phenyl)-2-(4-nitro-phenyl)-2,3-dihydro-benzo[e][1,3]thiazin-4-one [comp. (2)] was used as a synthone for the preparation of Schiff bases [comp.(3)-(7)]. The synthesis compounds were characterized by FT-IR, 1H NMR and spectrophotometric methods. Furthermore, silver nanoparticles was prepared by chemical reduction and characterized by X-Ray diffraction (XRD), infra-red spectrum (FTIR), atomic force microscope (AFM) and scanning electron microscope (SEM). The Ag NPs was used as a base nano metal for preparing Schiff bases-Ag NPs derivatives. The pure Ag NPs and Ag NPs functionalized Schiff bases nano compounds were used to check their effectiveness against four different types of bacterial (Staphylococcus aurous, Staphylococcus epidermidis, Escherichia coli and Klebsiella sp.) and one type of fungal (Candida albicans) by a serial dilution method.

In this work, quinazolinone derivatives were prepared, characterized by IR, UV, HNMR spectroscopy. Theoretically these compounds were studied

Agroup of benzimidazole derivatives bearing different heterocyclic moieties such as Schiff bases, 2-azetidinone and  4-thiazolidinone were efficiently prepared. The structures of the newly compounds were characterized by FTIRand ¹H NMR spectra. The synthesized compounds were evaluated for their antimicrobial activities against gram-positive and gram negative bacteria and fungi using the microdilution procedure.

The group of imidazoline derivatives is an important class of compounds that possess broad biological activity. Many derivatives that have been efficiently synthesized form 2-(-2,4-dimethoxyphenyl)-4,5dihydro-1H-imidazole as starting material to Synthesis of some derivatives. The structures were characterized by FTIR and 1H-NMR spectra. All The synthesized compounds were evaluated for their antimicrobial activities against two kind of bacteria (gram +ve) [ S. aureus, S.epidermi dis] and (gram –ve) [E.coli, Klebsiel lla spp] as well as fungi [C.albica ns] using the micro dilution procedure and compared with amoxicillin activity.