Schiff Base Research Articles

ON-OFF Control of Marangoni Self-propulsion via A Supra-amphiphile Fuel and Switch.

Marangoni self-propulsion refers to motions of liquid or solids driven by a surface tension gradient, and has applications in soft robots/devices, cargo delivery, self-assembly etc. However, two problems remain to be addressed for motion control (e.g., ON-OFF) with conventional surfactants as Marangoni fuel: (1) limited motion lifetime due to saturated interfacial adsorption of surfactants; (2) in- situ motion stop is difficult once Marangoni flows are triggered. Instead of covalent surfactants, supra-amphiphiles with hydrophilic and hydrophobic parts linked noncovalently, hold promise to solve these problems owing to its dynamic and reversible surface activity responsively. Here, we propose a new concept of 'supra-amphiphile fuel and switch' based on the facile synthesis of disodium-4-azobenzene-amino-1,3-benzenedisulfonate (DABS) linked by a Schiff base, which has amphiphilicity for self-propulsion, hydrolyzes timely to avoid saturated adsorption and provides pH-responsive control over ON-OFF motion. The self-propulsion lifetime is extended by 50-fold with DABS and motion control is achieved. The mechanism is revealed with coupled interface chemistry involving two competitive processes of interfacial adsorption and hydrolysis of DABS based on both experiments and simulation. The concept of 'supra-amphiphile fuel and switch' provides an active solution to prolong and control Marangoni self-propulsive devices for the advance of intelligent material systems.

Synthesis and Crystal Structure Studies of a New Complex of Co (III)-Schiff Base Derivative Derived from Isonicotinohydrazide

A new Co(III) complex prepared by the reaction of N'–(1–(pyridin–2 yl)ethylidene) isonicotinohydrazide (H2L) with Co(II) ion is reported in this paper. The H2L ligand is structurally characterized by elemental analysis, NMR, and infrared spectroscopies. The mononuclear complex [Co(HL)2]·Cl·3H2O (1), is characterized by infrared spectroscopy, elemental analysis, conductance, magnetic room temperature measurement and single X-ray diffraction. The complex crystallizes in the monoclinic system with space group P21/c. The parameters of the unit cell are a = 9.6818(3) Å; b = 25.1587(6) Å; c = 11.5481(3) Å;   β = 101.797(3) °; Z = 4; Rint = 0.0313 and wR(F2) = 0.0812. The asymmetric unit of the compound contains a discrete [Co(HL)2]+ cation one  free chloride anion and three uncoordinated water molecules. In the discrete cation one Co3+ ion two organic ligand molecules are present. The coordination polyhedron around the Co3+ center is best described as a distorted octahedral with CoN4O2 chromophore. The crystal structure of the complex is stabilized by intramolecular and intermolecular hydrogen bonds.

Photophysical Studies of a Zr(IV) Complex with Two Pyrrolide-Based Tetradentate Schiff Base Ligands.

The reaction of two equivalents of N,N'-bis(2-pyrrolylmethylidene)-1,2-phenylenediamine (H2bppda) with tetrabenzylzirconium provided the air- and moisture-stable eight-coordinate complex Zr(bppda)2. Temperature-dependent steady-state and time-resolved emission spectroscopy established weak photoluminescence (ΦPL = 0.4% at 293 K) by a combination of prompt fluorescence and thermally activated delayed fluorescence (TADF) upon visible light excitation at and around room temperature. TADF emission is strongly quenched by 3O2 and shows highly temperature-sensitive emission lifetimes of hundreds of microseconds. The lifetime of the lowest energy singlet excited state, S1, was established by transient absorption spectroscopy and shows rapid deactivation (τ = 142 ps) by prompt fluorescence and intersystem crossing to the triplet state, T1. Time-dependent density functional theory (TD-DFT) calculations predict moderate ligand-to-metal charge transfer (LMCT) contributions of 25-30% for the S1 and T1 states. A comparison of Zr(bppda)2 to related zirconium pyridine dipyrrolide complexes, Zr(PDP)2, revealed important electronic structure changes due to the eight-coordinate ligand environment in Zr(bppda)2, which were correlated to differences in the photophysical properties between the two compound classes.

Bletilla striata Polysaccharide-/Chitosan-Based Self-Healing Hydrogel with Enhanced Photothermal Effect for Rapid Healing of Diabetic Infected Wounds via the Regulation of Microenvironment.

The management of diabetic ulcers poses a significant challenge worldwide, and persistent hyperglycemia makes patients susceptible to bacterial infections. Unfortunately, the overuse of antibiotics may lead to drug resistance and prolonged infections, contributing to chronic inflammation and hindering the healing process. To address these issues, a photothermal therapy technique was incorporated in the preparation of wound dressings. This innovative solution involved the formulation of a self-healing and injectable hydrogel matrix based on the Schiff base structure formed between the oxidized Bletilla striata polysaccharide (BSP) and hydroxypropyltrimethylammonium chloride chitosan. Furthermore, the introduction of CuO nanoparticles encapsulated in polydopamine imparted excellent photothermal properties to the hydrogel, which promoted the release of berberine (BER) loaded on the nanoparticles and boosted the antibacterial performance. In addition to providing a reliable physical protection to the wound, the developed hydrogel, which integrated the herbal components of BSP and BER, effectively accelerated wound closure via microenvironment regulation, including alleviated inflammatory reaction, stimulated re-epithelialization, and reduced oxidative stress based on the promising results from cell and animal experiments. These impressive outcomes highlighted their clinical potential in safeguarding the wound against bacterial intrusion and managing diabetic ulcers.

Oxidovanadium(V) Schiff Base Complexes Derived from Chiral 3-amino-1,2-propanediol Enantiomers: Synthesis, Spectroscopic Studies, Catalytic and Biological Activity

Oxidovanadium(V) complexes, [(+)VOL1-5] and [(–)VOL1-5], with chiral tetradentate Schiff bases, which are products of monocondensation of S(‒)-3-amino-1,2-propanediol or R(+)-3-amino-1,2-propanediol with salicylaldehyde derivatives, have been synthesized. Different spectroscopic methods, viz. 1H and 51V NMR, IR, UV-Vis, and circular dichroism, as well as elemental analysis, have been used for their detailed characterization. Furthermore, the epoxidation of styrene, cyclohexene, and two monoterpenes, S(‒)-limonene and (‒)-α-pinene, using two oxidants, aqueous 30% H2O2 or tert-butyl hydroperoxide (TBHP) in decane, has been studied with catalytic amounts of all complexes. Finally, biological cytotoxicity studies have also been performed with these oxidovanadium(V) compounds for comparison with cis-dioxidomolybdenum(VI) Schiff base complexes with the same chiral ligands, as well as to determine the cytoprotection against the oxidative damage caused by 30% H2O2 in the HT-22 hippocampal neuronal cells in the range of their 10–100 μM concentration.

Saliva as a Diagnostic Tool for Early Detection of Exercise-Induced Oxidative Damage in Female Athletes

Although blood still remains the most commonly utilized medium to detect increased levels of oxidative damage induced by exercise, saliva diagnostics have gained increasing popularity due to their non-invasive nature and athlete-friendly collection process. Given that the contribution of various phases of the menstrual cycle to the levels of oxidative damage may differ, the aim of this study was to evaluate an agreement between salivary and plasmatic levels of lipid peroxidation products in female swimmers in both the follicular (F) and luteal (L) phases of the menstrual cycle at rest and following exercise. Twelve well-trained female swimmers aged 19.6 ± 1.1 years old were examined. We measured diene conjugates (DCs), triene conjugates (TCs), and Schiff bases (SBs) in lipids immediately after their extraction from both saliva and blood plasma. All female swimmers were studied two times each, in the two different phases of one menstrual cycle, before and after high-intensity interval exercise (HIIE). Salivary and plasmatic levels of DCs, TCs, and SBs significantly increased post-exercise compared to pre-exercise, in both the F and L phases. A high positive correlation was observed between the concentrations of DCs, TCs, and SBs in the saliva and blood plasma of participants in the F and L phases, both at rest and following HIIE. Ordinary least products regression analysis indicates that there was no proportional and differential bias in the data. The Bland–Altman method also declares that there was no differential bias, since the line of equality was within the 95% confidence interval of the mean difference between salivary and plasmatic levels of DCs, TCs, and SBs in female swimmers, in both the F and L phases, before and after HIIE. There was also no proportional bias in the Bland–Altman plots. Thus, this is the first study to report a high agreement between the quantifications of DCs, TCs, and SBs in the saliva and blood plasma of female swimmers in both the F and L phases, at rest and following HIIE.

Fluorescent Schiff Bases with Phenothiazine and Coumarin Moieties: Synthesis, Characterization, Photophysical, Electrochemical, Computational and Biological Studies.

We present the design and synthesis of four new schiff bases viz., two each of phenothiazine and coumarin derivatives. The structures were proposed based on FT-IR, 1H NMR, 13C NMR and mass spectral data. The photophysical, solvatochromic and electrochemical studies of all the compounds were carried out. Furthermore, theoretical studies such as density functional theory (DFT) were carried out to gain a better understanding of the compounds' intramolecular charge transfer properties and electronic structures. Good agreement was noticed between the HOMO-LUMO energy gap obtained from DFT studies and that calculated from absorption threshold wavelengths. All the compounds showed Stokes shifts in the range of 6345-11,405cm-1. These findings showed that the new schiff bases could be considered as attractive candidates for use in the development of OLEDs, organic electrical devices and optoelectronic devices. Newly synthesized compounds were tested for biological activities. When compared to conventional standards, gallic acid and indomethacin, the schiff bases showed better antioxidant and antiinflammatory activities, respectively.

Synthesis and characterization of a new eco-friendly dopamine derivative schiff base as an effective corrosion inhibitor for mild steel in acidic environment

The natural corrosion inhibitor behaviour of a newly synthesized dopamine derivative Schiff base (4-DBAB) has been inspected on mild steel in aggressive 1 M HCl using linear polarization, electrochemical impedance spectroscopy and potentiodynamic polarization techniques. The Schiff base was synthesized by eco-friendly pathway. Characterization of the synthesized new non-toxic inhibitor was performed using FT-IR and 1H-NMR spectroscopy techniques. The anti-corrosive efficiencies at optimum concentration of 4-DBAB inhibitor was 87.4% after 1 h and 98.4% after 120 h by impedance technique in acidic solution. The potential of zero charge of mild steel was also determined to elucidate the inhibition mechanism in the presence of the highest 4-DBAB solution. The atomic force microscopy and field emission scanning electron microscopy researches performed on surface morphology to provide additional support on the interaction between the mild steel surface and 4-DBAB molecules. Adsorption behaviour of the inhibitor was also studied at different durations by experimental inhibition results and showed the Langmuir isotherm involving chemisorption. Highlights A new dopamine-derived Schiff base (4-DBAB) with natural and environmentally friendly corrosion inhibition properties was synthesized. (Synthesis of eco-friendly compound). 4-DBAB demonstrated a high anti-corrosive efficiency after 120 hours in aggressive 1M HCl, as determined by impedance technique. (Exceptional corrosion inhibition). The determination of the potential of zero charge of mild steel provided insights into the inhibition mechanism in the presence of the highest 4-DBAB solution. (Mechanism elucidation). AFM and FE-SEM studies on surface morphology supported the interaction between the mild steel and 4-DBAB molecules, affirming its corrosion inhibition properties. (Surface interaction analysis).

Synthesis and Characterization of Novel Schiff Base Complexes of Cu (II), Cd (II), Ni (II), and Co (II) Ions with N'-(4-Nitrobenzylidene) Isonicotinohydrazide

The Schiff base complexes of Cu (II), Cd (II), Ni (II), and Co (II) ions were synthesized utilizing Schiff base ligand. The Schiff base ligand was produced through the reaction of isoniazid with equimolar quantities of p-nitrobenzaldehyde yielding final product of N'-(4-nitrobenzylidene) isonicotinohydrazide (L). The ligand and its metal complexes were assessed by TLC, melting point determination, conductivity measurement, FTIR spectroscopy, magnetic moment analysis, and UV-Vis spectroscopy. The FTIR spectra revealed that the Schiff base ligand established coordination bonds with the metal ion by utilizing the nitrogen (N) atom of the azomethine group and the oxygen (O) atom of the carbonyl group. All synthesized compounds exhibited cytotoxicity against brine shrimp nauplii, thereby confirming their biological activity. [Ni(L)2] and [Cd(L)2] complexes displayed greater cytotoxic or anticancer efficacy. In addition, the antibacterial efficacy of both ligand and its complexes was investigated against several harmful bacteria. In comparison with the ligand (L), the antibacterial activity of the complexes of [Cu(L)2], [Cd(L)2], and [Ni(L)2] is higher, whereas that of [Co(L)2] is lower.

Enhanced Efficiency of Silicon Solar Cell by New Salophen Complexes Embedded PMMA as Light Concentrators

AbstractThe Schiff base N,N-bis(salicylidene)-o-phenylenediamine (salophen) was prepared by the condensation of salicylaldehyde with o-phenylenediamine in ethanol solution. Two new Zn(II) and Ni(II) salophen complexes, were synthesized, fully characterized by infrared (IR), 1H NMR spectroscopic measurements, UV–Vis spectra, photoluminescence (PL), and X-ray diffraction (XRD). The prepared complexes were used as phosphors to fabricate complexes/PMMA slab-based luminescent solar concentrators (LSC). The thermal stability of pure and doped PMMA polymer was examined by differential scanning calorimetry. Various parameters such as the optical energy gap, refractive index, AC and DC conductivity, dielectric constant, dielectric loss, Urbach energy, fluorescence quantum yield, and Stokes shift have been calculated and discussed. Optical absorption is carried out in wavelength region 200–900 nm at room temperature before and after the samples have been exposed to sunlight for up to 8 h. Photodegradation studies showed that the Zn(II) complex/PMMA LSC has the lowest rate of degradation compared with Ni(II) complex/PMMA LSC with the same concentration (0.06% weight). I–V characteristics of the photovoltaic devices with and without collectors were examined. The PV cell coupled with LSC shows an increase in maximum efficiency by about 50% compared to the normal one. This indicates that the proposed technique is very useful for improving the efficiency of solar cells.

Synthesis of novel bi-Zwitterion Schiff base derivate from 4‑hydroxy-2H-pyran-2-one: DFT/HSA-interactions, thermal, physicochemical, TD-DFT and optical activity

A novel tetradentate bi-Zwitterion Schiff base (SB): 3,3′-((1E,1′E)((oxybis(4,1-phenylene))-bis-(azanylylidene))-bis(ethan-1-yl-1-ylidene))bis(4‑hydroxy-2H-pyran-2-one) was synthesized, via reflux condensation of 3-acetyl-4‑hydroxy-6-methyl-2H-pyran-2-one with 4,4′-oxydianiline in methanol. The SB ligand was characterized using various physicochemical techniques, including 1HNMR , elemental analysis (CHN-EA), XRD, MS, UV–vis, and FT-IR. The XRD analysis confirmed the presence of a bi-zwitterionic salt form, characterized by intra-H-bond interactions between [N+—H…−O] groups. Hirschfield surface analysis (HSA) and MEP/MAC/NPA were conducted to gain insight into the intra/intermolecular hydrogen bond interactions of the molecule. The completion of the SB dehydration reaction was UV–vis., tracked by studying the behavior of the reactants before and after mixing. Additionally, the absorbance/transmittance, TD-DFT, and optical properties of the SB were evaluated. Finally, the TG/DTG analysis was used to determine the thermal stability of the desired SB ligand.

Coumarin Schiff Base Derivatives with 4’-Alkoxy Biphenyl-4-carboxaldehyde: Synthesis, Mesomorphic studies and DFT Calculations

Two homologous series of coumarin Schiff base derivatives with 4’-alkoxy biphenyl-4-carboxaldehyde have been designed and synthesized. All the compounds were analyzed IR, 1H-NMR, 13C-NMR, ESI-MS and CHN analysis followed by mesomorphic properties polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) analysis. In the first homologous series BPS(6-16), Schiff base of 7-alkoxy-3-aminocoumarin with 4’-alkoxy biphenyl-4-carboxaldehyde, alkoxy chain length was varied systematically at both end of the molecules such as n=6,8,10,12,14,16. In this series, BPS(6-10) (n=6,8,10) exhibited enantiotropic nematic(N) and smectic C (SmC) mesophase and turned to monophasic on increasing the chain length n=12,14,16 in BPS(12-16) with stable SmC mesophase. While in the second homologous series 10BPU(2-16), systemic variation of alkoxy chain length was carried out at coumarin end only (n=2-18) and 4’-decyloxy-biphenyl-4-carboxaldehyde was used for Schiff base formation. In the this series, early member of the series with n=2,3 showed enantiotropic very stable (∼ 145 °C) nematic mesophase, while N as well as SmC mesophase were observed for n=4-8 at, whereas with increase of chain length stability of nematic mesophase was decreased and that of SmC was increased. Higher membered analogous 10BPU(12-16) exhibited SmC mesophase with stability in the rage of 130-160 °C. VT-XRD analysis was also confirmed the tilted SmC mesophase in this class of compounds. For both the series, all compounds were studied for the DFT calculations as well as literature molecules with similar variations. Based on the calculated structural (length, aspect ratio) and electronic (dipole moment, polarizability) parameters were correlated with mesomorphic behaviour observed for literature compounds and compounds from both the series followed by the detailed discussion.

Synthesis, characterization, thermal, theoretical studies, antimicrobial, antioxidant activity, superoxide dismutase-like activity and catalase mimetics of metal(II) complexes derived from sugar and Schiff base

Abstract Scientists are searching for reactive oxygen species, which have been associated with various health issues like heart problems, neurological disorders, inflammation, and aging. Salen complexes have proven to be effective in multiple oxidative stress situations and have been used as catalase and superoxide mimetics. To explore this further, three mixed complexes were synthesized using a Schiff base (salen) and a sugar (d-glucose) with Co(II), Ni(II), and Cu(II) ions. These complexes were then diagnosed by different analytical and spectral techniques. Stoichiometry, stereochemistry, some physical properties, and the method of bonding complexes were measured. Comparisons of the IR and 1HNMR spectra of the ligands with the complexes demonstrated the involvement of the azomethine group of the ligand in the chelation process. The mass spectra and TGA agree with the proposed formula of the complexes, and the conductivity and UV–Vis data supported the octahedral geometry of the complexes, and information was obtained from partial parameter calculations by molecular modeling. The metal complexes exhibited strong antimicrobial and antioxidant properties when compared to standard drugs. The like-superoxide and catalyst mimetic complexes were screened using DPPH ABTS, revealing their effectiveness.

A specific, ultra-sensitive and rapid naked-eye on-site recognition of CN– and Cu2+ ions in tap water using an isonicotinohydrazide-salisaldehyde hybrid probe

Schiff base 1, namely (E)-N'-(2-hydroxy-3-methoxybenzylidene)isonicotinohydrazide, exhibits amide-iminol tautomerism in its molecular structure and functions as a colorimetric sensor for detecting cyanide (CN–) and copper ions (Cu2+) in ethanol/H2O (1:1). Compound 1 can distinguish CN– and Cu2+ ions from various competing ions based on unique color and spectral alterations. Spectral analyses reveal the prevalence of the iminol-form of 1 over the amide-form, enabling the selective detection of CN– and Cu2+ ions. When CN– is present, deprotonation occurs in both the phenolic and iminolic groups, leading to increased conjugation along molecule 1, as confirmed by 1H NMR spectroscopy. On the other hand, Cu2+ sensing involves coordination with 1 through a tridentate moiety, specifically interacting with the azomethine nitrogen atom as well as the deprotonated phenolic and iminolic groups. This mechanism allows for superior detection of Cu2+ compared to CN–. Key features of this sensor include its selectivity, sensitivity (with detection limits of 4.05 nM for CN– and 1.7 nM for Cu2+), a rapid response (less than 5 s), and the capability for on-site monitoring of CN– and Cu2+ ions in tap water using either solution or solid kits. Additionally, DFT calculations have validated the influence of Cu2+ and CN– on the system's electronic structure, as demonstrated by the results of MEP maps and changes in gap energy values.

Preparation of amino cellulose aerogel and its formaldehyde adsorption properties

The aerogel prepared from cellulose has the advantages of low density, high porosity, large specific surface area, good gas diffusion and adsorption space, which is a good gas adsorption material. In this study, microcrystalline cellulose was used as raw material, and LiBr ionic liquid was used as a solvent system. In addition, cellulose aerogel was modified by polyethyleneimine, which retained three-dimensional network structure and had excellent formaldehyde adsorption capacity. The adsorption capacity of polyethyleneimine-modified cellulose aerogel (PCA) to formaldehyde can reach 12.3 mg/g at 25 ℃. It was found that the adsorption capacity of PCA aerogel for formaldehyde changed with the increase in nitrogen content. The adsorption of formaldehyde was mainly through the chemical adsorption of the Schiff base reaction between NH2 and formaldehyde molecules in polyethylenimine (PEI).

New nanometric metal complexes based on thiazole derivative as potential antitumor and antimicrobial agents: Full structural elucidation, docking simulation and biological activity studies

Novel Mn(II), Ni(II), Zr(IV) and Cd(II) nanosized complexes of thiazole Schiff base derivative (HL) were synthesized for further medicinal applications. The inspected complexes were fully characterized using elemental and thermal analyses in addition to infrared spectroscopy (IR) and nuclear magnetic resonance (1HNMR). Electronic absorption spectra, X-ray powder diffraction (XRD), transmittance electron microscopy (TEM), molar conductance and magnetic moment were also measured and explained. The brought about data revealed that the ligand–metal chelation happened through the N atom of N = N group, and the ortho-dehydrogenated phenolic O atom to form the chelates where the metal binds with one molecule of the parent ligand. All applied spectroscopic and analytical techniques confirmed tetrahedral geometry in Mn(II) and Ni(II) complexes and octahedral geometry for Cd(II) and Zr(IV) complexes. The ligand, Mn(II), Ni(II), and Zr(IV) chelates' XRD patterns indicated an amorphous character where the Cd(II) complex's nature is crystalline. Transmission electron microscopy (TEM) images of the prepared compounds showed that the surface morphology is uniform and homogeneous. Also, the metal ions distribute through the complexes' surface in a nanosized nature. The metal complexes have been simulated by docking in the co-crystal structures of the liver cancer and breast cancer proteins with PDB IDs, 2JW2 and 3S7S, successively. Antibacterial, antifungal and anticancer activities for the ligand that has been produced and its complexes were achieved. The most encouraging antitumor results were acquired by Ni(II) chelate which exhibited an IC50 of 23.52 µg/ml contra MCF-7 cells (human breast cancer) which is lower than the reference 5-Fluorouracil (5-FU, IC50 = 28.00 µg/ml).

Porphyrin-based Schiff base fluorescent probe: mercuric ion recognition by naked eye colorimetric analysis and application of test strip detection

Porphyrin-based Schiff base fluorescent probe: mercuric ion recognition by naked eye colorimetric analysis and application of test strip detection

Low hysteresis, high sensitivity, fast response, and recovery time of humidity sensor based on Schiff bases material

Low hysteresis, high sensitivity, fast response, and recovery time of humidity sensor based on Schiff bases material

Cerric ammonium nitrate catalyzed eco-friendly green synthesis of chitosan Schiff base using PEG-400 as an anticancer agent against gastric cancer cells via inhibiting EGFR

The present study was conducted to scrutinize the pharmacological effect of oxazole-embedded Chitosan as an anticancer agent against gastric cancer cells. This compound was synthesized using the classical Schiff base reaction but utilizing the novel green chemical process where cerric ammonium nitrate (CAN) was used as a catalyst in the PEG-400 as solvent media. The target compound was obtained with an excellent yield at the catalyst loading of 5% CAN concentration in 15 min. The Kinase-Glo Plus luminescence kinase assay kit was used to determine the EGFR inhibitory activity of compound 1 where it showed potent activity with IC50 of 2.14 µM. Its effect was also determined on the cellular viability of the Human gastric cancer cell line (SGC7901), liver cancer cell line (HepG2), and lung cancer cell line (A549), where it exhibits potent activity against SGC7901. The compound further showed the concentration-dependent inhibitory effect on migration and invasion of SGC7901. In RT-qPCR analysis, the compound showed induction of apoptosis of SGC7901 cells possibly by restoring the expression of Bcl-2 and Bax near to normal, and inhibition of the mRNA expression of EGFR in a concentration-dependent manner. KEY WORDS: Schiff base, Chitosan, EGFR, mRNA, apoptosis, Bcl-2 Bull. Chem. Soc. Ethiop. 2024, 38(4), 1091-1101.                                                    DOI: https://dx.doi.org/10.4314/bcse.v38i4.22

Synthesis and Characterization of some new heterocyclic derivatives from aromatic carbonyl ‎compounds and carboxylic acids with Evaluation some of them for biological activity

     In this research investigation, a total of eighteen diverse tetra- and penta-lateral cyclic compounds were synthesized. These included 1,3,4-thiadiazole, thiazolidin-4-one (via an alternative method), 1,2,4-triazole, carbothioamide, thiazole-4-one, azetidin-2-one, and oxazole. The synthesis procedure entailed a sequence of reactions. The thiazolidine-4-one 1 was obtained by reaction p-aminobenzoic acid with thiosemicarbazide, followed by treatment with p-tolualdehyde to produce Schiff base 2. Reaction Schiff base 2 with mercaptoacetic acid in dry benzene was carried out to produce thiazolidine-4-one 3. In another synthesis pathway, the esterification of p-nitro benzoic acid with ethanol in the presence of sulfuric acid was obtained to formation of compound 4. Compound 4 was subsequently reacted with thiosemicarbazide, yielding compound 5. Cyclization of compound 5 was then achieved using 4% sodium hydroxide solution. This formed the 1,2,4-triazole heterocycle, designated compound 6. Thiosemicarbazone 7-9 were prepared by reaction of thiosemicarbazide with different aldehydes. Additionally, 2-substituted-1,3-thiazolidine-4-one derivatives 10-12 were synthesized through the reaction of thiosemicarbazone with chloroacetic acid in the presence of anhydrous sodium acetate. The Oxazole derivative 15 was obtained through a series of reactions starting with the reaction of p-amino benzoic acid with ethyl chloroacetate, resulting in compound 13. Compound 13 was then treated with urea to obtain compound 14, followed by a reaction with 4-phenyl phenacyl bromide to yield the final product, the Oxazole derivative 15. The 2-aminooxadiazole derivative 16 was synthesized by reaction urea with 4-bromoacetophenone which was reacted with 4-bromobenzaldehyde to produce Schiff base derivative 17. Finally, β-lactam 18 is obtained through reaction Schiff base with chloroacetyl chloride in the presence of triethyl amine. FT-IR, 1H-NMR, and 13C-NMR spectroscopy were used to confirm their proposed structures. Moreover, the antibacterial and antifungal activities of certain synthesized compounds, specifically 2,3,6,11,13,15,17, and 18, were assessed against Staphylococcus aureus, Escherichia coli, and Candida albicans, demonstrating encouraging outcomes.Keywords: Antibacterial, antifungal activity, oxadaizole, heterocyclic derivatives, Oxazole.