Acac Research Articles

Design, synthesis and biological assessment of novel pyridopyrimidine and chromenopyridopyrimidine analogues

The important pharmacological and medicinal facts concerning chromenopyridopyrimidine and pyridopyrimidine compounds motivated us to condense our efforts into constructing novel derivatives with valuable biological properties. A series of new chromenopyridopyrimidine 2–4 and different substituted pyridopyrimidine derivatives 6–9 and 13 were synthesized in one pot three components base-catalyzed reaction of aminothiouracil 1 with various aldehydes and different active methylene compounds. Also, substituted pyridopyrimidines 10 and 11 were synthesized when thiouracil 1 reacted only with cinnamaldehyde and acetyl acetone. The synthesized compounds’ structure was verified by microanalysis and spectral data, the biological studies demonstrated antibacterial and antifungal activities against E. coli, Pseudomonas aeruginosa, S. aureus, and C. albicans.

Synthesis, characterization, and color performance of bis-azo and bis-pyrazole derivatives for dyeing of polyester

In this study, a novel series of bis-azo dyes 3–10 were synthesized via a two-step process. Initially, benzene-1,4-bis(diazonium) chloride was reacted with several active methylene compounds, such as ethyl acetoacetate, acetyl acetone, ethyl cyanoacetate, and malononitrile. yielding the corresponding bis-azo dyes 3–6. Subsequently, these dyes were cyclized through condensation with phenylhydrazine, resulting in the formation of bis-pyrazole derivatives 7–10. Comprehensive spectroscopic characterization, employing techniques like infrared (IR), nuclear magnetic resonance (NMR), and ultraviolet-visible (UV–Vis) spectroscopy, along with elemental analysis, elucidated the structural features, and electronic transitions of the synthesized dyes. The electronic absorption properties were investigated experimentally and computationally, revealing bathochromic and hypsochromic shifts influenced by substituents and tautomeric forms. The dyes showcased excellent dyeing performance on polyester fabrics, exhibiting notable color strength, perspiration fastness, light fastness, and wash fastness. Theoretical investigations of the electronic properties were conducted utilizing Density Functional Theory (DFT) methodology, employing the B3LYP functional with the 6–31G(d,p) basis set, enabling a comprehensive understanding of the structure-performance relationships governing the dyeing behavior of these dyes on polyester.

Synthesis of New Heterocyclic Derivatives from 4-(3, 5-Dimethyl-1-phenyl-1H-pyrazol-4-ylazo)- benzoic acid

In this work pyrazolin derivatives were prepared from the diazonium chloride salt of 4-aminobenzoic acid. Azo compounds were prepared from the reaction of an ethanolic solution of sodium acetate and calculated amount of active methylene compound namely, acetyl acetone to obtain the corresponding hydrazono derivative (1). Cyclocondensation reaction of compounds (1) with hydrazine hydrate and phenyl hydrazine in boiling ethanol affording the corresponding pyrazoline-5-one derivatives of 4-aminobenzoic acid (2,3). Then compound (3) was reacted with thionyl chloride to give the corresponding acid chloride derivative(4), followed by conversion into the corresponding acid hydrazide derivative (5) carboxylic acid thiosemicarbazide (11), esters (14,15), thioesters (16,17) and amides (18,19), when treated hydrazine hydrate, thiosemicarbazide, alcohols, alkylthiol and secondary amines in dry refluxing benzene; respectively. Schiff's bases (6-8) were prepared by refluxing of compound (5) with different aldehydes and ketons, then two compounds from the Schiff's bases were cyclized with ?-mercapto acetic acid to give (9 and 10). Furthermore, 1,2,4-triazole derivative (12) have been also prepared by refluxing thiosemicarbazide derivative with sodium hydroxide solution (4%) followed acidification of the result using (10%)hydrolic acid. Moreover, a thiadiazole derivative (13) has been prepared by treatment of thiosemicarbazide derivative with concentrated sulfuric acid as cyclyzing agent. Finally, oxadiazole derivative (20) has prepared by condensation of its acid hydrazide derivative with carbon disulfide in basic medium.

Multifaceted biomedical applications of bismuth oxide-doped bioactive glass: Synthesis challenges, characterization and potential clinical implications

Herewith, the present work reports a facile synthesis method of Bi2O3 doped 70 SiO2.30CaO binary bioactive glass system termed as modified Bi-BG (acronymed as mBi-BG) that indicates successful incorporation of Bi3+ into the silicate glassy network, on prior complex formation of the precursor bismuth nitrate salt with acetyl acetone to address the rapid decomposition rate of precursor bismuth nitrate. The binary bioactive glass composition as above mentioned (70 SiO2.30CaO) is named as BG/Control. The synthesis methodology addresses inherent challenges encountered in traditional sol-gel derived bismuth oxide incorporated bioactive glass (Bi-BG) synthesis wherein yellow coloured bismuth oxide gets separated from the glassy network as confirmed by XRD phase analysis. Next, mBi-BG (modified Bi-BG) was synthesized via modifying the sol gel method by introducing a chelating agent acetyl acetone to stabilize the precursor Bi (NO3)3 salt, and was characterized using XRD, FTIR, FESEM-EDX. TG-DSC and BET isotherm. In vitro bioactivity studies illustrate the formation of hydroxyapatite crystals on mBi-BG surface indicating its potential for bone repair and regeneration. Additionally, mBi-BG exhibits significant effect against Staphylococcus aureus (gram-positive) bacterial strain, highlighting its utility in preventing bacterial infections at surgical sites. Radiographic imaging of mBi-BG reveals excellent radiopacity comparable to human bone, rendering it suitable for image-guided surgeries and fluoroscopic procedures. In summary, mBi-BG emerges as a versatile biomaterial with enhanced bioactivity, antibacterial efficacy and radiopacity, thereby offering novel avenues in medical treatment modalities and patient care.

Mononuclear nickel(II) and copper(II) coordination compounds with ligands based on acetyl(benzoyl)acetone S-methylisothiosemicarbazones and 8-quinolinecarboxaldehyde. Synthesis and crystal structure

Template condensation of S-methylisothiosemicarbazones of acetyl- or benzoylacetone with 8-quinolinecarboxaldehyde in the presence of nickel(II) and copper(II) ions gave four new mononuclear coordination compounds [NiL1]I (I), [CuL1I] (II), [NiL2]I (III) и [CuL2I] (IV). The chemical composition of the products was confirmed by elemental analysis, IR spectroscopy, and mass spectrometry, and the crystal structure of compounds I and II was determined by X-ray diffraction analysis (CCDC no. 2266386, 2266387). X-ray diffraction study revealed a square planar coordination environment of the central ion of the cationic Ni(II) complex and square pyramidal geometry for the molecular Cu(II) complex.

Synthesis, DFT studies on a series of tunable quinoline derivatives.

The synthesis, Density Functional Theory (DFT) calculations, and photo physical characteristics of a range of quinoline derivatives have been described in the present work. Initially, the innovative derivatives are synthesized through the cyclization of 2-amino-5-nitrobenzophenone with either acetyl acetone or ethyl acetoacetate, followed by reducing the nitro group to an amine. Subsequently, these compounds undergo an acid-amine cross-coupling reaction. The investigation shows the DFT and photo physical properties of these substances. It is noteworthy that compound 6z exhibits the most remarkable Stokes shift among the fluorophores investigated. Furthermore, the research also provides insights into the electrophilicity index, Electronegativity, chemical potential, chemical hardness and softness properties. These properties are determined by utilizing Density Functional Theory (DFT) calculations and evaluating electron potential efficiency and using computational methods Time-Dependent Density Functional Theory (TD-DFT) to predict absorption spectra in molecules at the B3LYP/6-31G'(d,p) level/basis.

Acetylacetone Boosts the Photocatalytic Activity of Metal–Organic Frameworks by Tunable Modification

Typical metal–organic frameworks (MOFs) usually suffer from a limited visible light-trapping ability and easy recombination of charge carriers, hindering their photocatalytic applications. Acetylacetone (AA), leveraging its exceptional coordination capabilities, serves as a versatile and effective modifier for enhancing the photocatalytic activity of MOFs via a post-synthesis approach. The synthesis of diketone-anchored MOFs with AA can be achieved by first diazotizing the amino groups on the ligands of MOFs, followed by a condensation reaction between AA and the resulting azide. Gradient AA loadings ranging from 17% to 98% were obtained, showcasing the tunability of this approach. Interestingly, a sub-stoichiometric effect was exhibited between the AA loading and the visible photocatalytic performance of the modified photocatalyst. The singlet oxygen yields of MIL-125-AA-37% and MIL-125-AA-54% were about 1.3 times that of MIL-125-AA-17% and 3.0 times that of MIL-125-AA-98%. The improved photocatalytic activity could be attributed to the fact that the AA modification altered the electron density of the Ti metal center, leading to the creation of a significant amount of oxygen defects. This alteration resulted in a reduction in the recombination of charge carriers and thus a better charge separation. In short, AA modification provides a new strategy to maximize the visible photocatalytic performance of MOFs.

Synthesis, Thermogravimetric and Spectroscopic Characterizations of New Tetraazamacrocyclic Schiff Base Ligand and Some Metal Complexes

In the present study, metal complexes of Mn(II), Ni(II), Co(II), Cu(II) and Hg(II) were synthesized using new Tetraazamacrocyclic Schiff Base (5E,8E,14E,17E)-6,8,15,17-tetramethyl-1,2,3,4,4a,7,9a,10,11,12,13,13a,16,18a-tetradecahydrodibenzo [b,i][1,4,8,11]tetraazacyclotetradecine (L) derived from 1,2-diamino cyclo hexane with the acetyl acetone. Compounds have been exanimated and confirmed by fourier-transform infrared (FT-IR), ultraviolet-visible (UV-visible), proton nuclear magnetic resonance (1HNMR), carbon nuclear magnetic resonance (13CNMR), microelemental analyses (CHN), thermal analysis (TG), conductivity and magnetic susceptibility. The propose geometry for all complexes [MLCl2] structures were octahedral. Thermogravimetric of cobalt complex was carried out in two steps by fission into several small aggregates.

Fabrication of Functional Coating Layer for Emerging Transparent Electrodes using Antimony Tin Oxide Nano-colloid

This study fabricated a functional coating layer for transparent electrodes using antimony tin oxide nanopowder. The wet grinding method was employed to create a stable dispersion solution of antimony tin oxide nanopowder with aminopropyl tri-methoxysilane and acetyl acetone as primary dispersing agents. Various concentrations of these dispersing agents were used to determine optimal conditions, followed by a gel reaction to form a stable solution. The primary objective was to provide a viable alternative to indium-based transparent electrodes, specifically indium tin oxide, by incorporating antimony oxide. This approach not only addresses limitations associated with indium, but also enhances mechanical properties. The methodology involves the utilization of antimony tin oxide nanopowder and various solvents including ethanol and aforementioned dispersing agents to create a stable antimony tin oxide sol through wet grinding. Effects of dispersant concentration and milling time on the secondary particle size of the antimony tin oxide sol were thoroughly evaluated. Furthermore, this study examined sheet resistance of resulting coating layers by conducting a comparative analysis between antimony tin oxide and indium tin oxide under similar conditions. Findings of this study meticulously detailed in subsequent sections of the manuscript provide valuable insights into optimizing the entire process, encompassing synthesis, coating, heat treatment, and the production of high-quality transparent conductive coatings. These techniques and outcomes can significantly contribute to the development of more sustainable and cost-effective alternatives to traditional indium-based transparent electrodes.

Effect of Nickel Acetyl Acetonate as Lubricant Additive in Base Oils with Different Molecular Structure on In-Situ Formation and Tribomechanism of Carbon-Based Tribofilms of Steel-Steel Sliding Pair

Effect of Nickel Acetyl Acetonate as Lubricant Additive in Base Oils with Different Molecular Structure on In-Situ Formation and Tribomechanism of Carbon-Based Tribofilms of Steel-Steel Sliding Pair

Design, synthesis, antimicrobial evaluation, molecular docking studies, and in silico prediction of ADME properties for novel pyrazolo[1,5‐a]pyrimidine and its fused derivatives

AbstractDienamine 2 was synthesized by reacting 5‐aminopyrazole 1 with two moles of (DMF DMA). Enamine 2 underwent subsequent reactions with various reagents in different reaction media, leading to the formation of distinct compounds. In an acidic environment, enamine 2 reacted with acetyl acetone, benzoyl acetone, dimedone, and ethyl acetoacetate, resulting in the synthesis of compounds 9a, 9b, 13, and 17, respectively. Conversely, in a basic medium, dienamine 2 combined with malononitrile, ethyl cyanoacetate, and malononitrile dimer, yielding compounds 21a, 21b, and 25. Moreover, by reacting with ammonium acetate in acetic acid, dienamine 2 produced compounds 28. The synthesized compounds underwent in vitro testing against various bacterial and fungal strains, revealing significant antibacterial activity against hazardous bacterial strains. To identify potential bacterial targets, an in‐silico study was initiated. Molecular docking investigations indicated that compound 25 exhibited the highest binding affinity toward dihydrofolate reductase and penicillin‐binding proteins. Furthermore, compound 25 demonstrated robust physiochemical properties, bioavailability, and drug‐like characteristics. These results collectively suggest the potential of compound 25 as a promising antibacterial agent with favorable drug properties.

Convenient One‐Pot Synthesis and Biological Evaluation of New 3,5‐Dimethyl‐1H‐pyrazole‐1‐carbothiohydrazide Derivatives as Anti‐Tumor Agents

AbstractPyrazole compounds have garnered attention due to their potential biological and medicinal qualities. Therefore, the purpose of the research being described is to utilize 3,5‐dimethyl‐1H‐pyrazole‐1‐carbothiohydrazide (1) as a starting material in a one‐pot synthesis to create novel pyrazole derivatives with potential biological applications. When either ethanol or acetic acid was added, components 1 and 1,3‐diphenylpropane‐1,3‐dione (2) reacted to produce derivative 3. Compound 1, when combined with ethanol, chemical 2, or acetyl acetone 5 and triethylamine, yielded chemicals 4 and 6 respectively. When ingredient 1 was mixed with ethyl cyanoacetate (7), stearic acid (10), or carboxylic acids 12 a–c, 9, 11, and 13 a–c were formed as a result. The equivalent 1,3,4‐thiadiazine derivatives, 15 and 17, were produced when 1 was mixed with either 14 or 16. The developed compounds′ cytotoxic properties were evaluated against lung and liver cancer. Our research identified a number of interesting bioactive chemicals, among which chemical 17 exhibited the greatest effectiveness against lung and liver cancer as well as the highest selectivity index measurements. It indicated a strong IC50 value of 5.35 and 8.74 μM, accordingly, when compared with 3.78 and 6.39 μM for the reference medication cisplatin. Additionally, its safety for use has been confirmed.

Mononuclear Nickel(II) and Copper(II) Coordination Compounds with Ligands Based on Acetyl(benzoyl)acetone S-Methylisothiosemicarbazones and 8-Quinolinecarboxaldehyde. Synthesis and Crystal Structure

Mononuclear Nickel(II) and Copper(II) Coordination Compounds with Ligands Based on Acetyl(benzoyl)acetone S-Methylisothiosemicarbazones and 8-Quinolinecarboxaldehyde. Synthesis and Crystal Structure

Pervaporation dehydration of an isopropanol aqueous solution using microporous TiO2-SiO2-OCL (Organic chelating Ligand) composite membranes prepared under different firing conditions

Microporous TiO2-SiO2 composite membranes intended for use in the pervaporation dehydration of a water/isopropanol mixture were prepared via the sol–gel method using acetylacetone (ACA) as an organic chelating ligand (OCL). TiO2-SiO2-ACA sols were prepared by using titanium (IV) propoxide (TiTP), an alkoxide of Ti, tetraorthoethylsilicate (TEOS), an alkoxide of Si, and ACA, as a composite of TiO2 and SiO2 with coordinating OCL to Ti. The dried gels were fired at 300 °C under N2 or at 500 °C under air, and were analyzed via FT-IR. Both powders had Ti-O-Si bonds, however, OCL in the powder fired at 500 °C in air has decomposed and removed. The TiO2-SiO2-ACA sols were applied to alumina plates and fired at either 300 °C under N2 or at 500 °C under air to check the water-contact angle, which indicated that the OCL was retained on the plates fired at 300 °C under N2 and were more hydrophobic than when fired at 500 °C under air. TiO2-SiO2-ACA composite membranes were fabricated by coating either the TiO2-SiO2-ACA sol layer fired at 300 °C under N2 or that fired at 500 °C under air onto a TiO2-SiO2 intermediate layer with an α-alumina support. The pore sizes of both membranes were estimated via the NKP method for single-gas permeance at 200 °C. The mean pore sizes of the membranes fired under N2 at 300 °C and under air at 500 °C were 0.47 nm and 0.68 nm, respectively, which suggested the possibility of pore size control via firing conditions. Pervaporation tests of the TiO2-SiO2-ACA composite membranes in a water/isopropanol mixture (IPA: 90 wt%) showed that the membranes fired under air at 500 °C and under N2 at 300 °C had values for permeation flux of 0.90 and 0.13 kg/(m2 h) and separation factors of 667 and 98 at 50 °C, respectively. The higher permeation flux of the membrane fired under air at 500 °C was due to the influence of a larger pore size as well as to a more hydrophilic surface. On the other hand, the separation factor was also higher for the membrane fired under air at 500 °C, because the hydrophilic surface facilitated water permeation. These results indicate the possibility of using firing conditions to control both the pore size and the surface properties of microporous TiO2-SiO2-ACA composite membranes for use in PV separation.

Unleashing the power of acetylacetone: Effective control of harmful cyanobacterial blooms with ecological safety

Harmful algal blooms resulting from eutrophication pose a severe threat to human health. Acetylacetone (AA) has emerged as a potential chemical for combatting cyanobacterial blooms, but its real-world application remains limited. In this study, we conducted a 42-day evaluation of AA's effectiveness in controlling blooms in river water, with a focus on the interplay between ecological community structure, organism functional traits, and water quality. At a concentration of 0.2 mM, AA effectively suppressed the growth of Cyanobacteria (88 %), Bacteroidia (49 %), and Alphaproteobacteria (52 %), while promoting the abundance of Gammaproteobacteria (5.0 times) and Actinobacteria (7.2 times) that are associated with the degradation of organic matter. Notably, after dosing of AA, the OD680 (0.07 ± 0.02) and turbidity (8.6 ± 2.1) remained at a satisfactory level. AA induced significant disruptions in two photosynthesis and two biosynthesis pathways (P < 0.05), while simultaneously enriching eight pathways of xenobiotics biodegradation and metabolism. This enrichment facilitated the reduction of organic pollutants and supported improved water quality. Importantly, AA treatment decreased the abundance of two macrolide-related antibiotic resistance genes (ARGs), ereA and vatE, while slightly increased the abundance of two aminoglycoside-related ARGs, aacA and strB. Overall, our findings establish AA as an efficient and durable algicide with favorable ecological safety. Moreover, this work contributes to the development of effective strategies for maintaining and restoring the health and resilience of aquatic ecosystems impacted by harmful algal blooms.

In Vitro Evaluation of Certain 6-Hetero Aryl-5-Hexene-2, 4-Diones and Their Metal Complexes for Cytotoxic Activity

A series of 6-Hetero aryl-5-hexene-2, 4-diones (1a-b) and their Cu (II) complexes (1c-d) of ML2 stoichiometry were synthesized by condensation of heterocyclic aldehydes with acetyl acetone through boric anhydride mediated mechanism. Boric anhydride act by blocking the medial methylene group of acetyl acetone and provides a new pathway other than facile Knoevenagel condensation. All the final structures were assigned on the basis of IR, 1H NMR and mass spectra analysis. The test compounds were studied for short term in vitro cytotoxicity using Dalton’s Lymphoma Ascites cell lines (DLA). The compound code 1C and 1D found to show significant cytotoxic action.

Fabrication of fuel electrode supported proton conducting SOFC via EPD of La2Ce2O7 electrolyte and its performance evaluation

The proton conducting La2Ce2O7 electrolyte has already been shown to be chemically more stable to H2O and CO2 than BaCeO3 based electrolyte materials. It has become widely popular as an alternative electrolyte for low to intermediate temperature operation in solid oxide fuel cells. Few initial studies have reported the fabrication of LCO-based fuel cells using the co-pressing process. Here, we present an alternative, simple, cost-effective and efficient method for the deposition of uniform and dense La2Ce2O7 electrolyte coatings, which is a key requirement for any fuel cell fabrication process. In this work, La2Ce2O7 is synthesized by a conventional solid state reaction route and we have established the process of fuel cell fabrication followed by its investigation for SOFC application as electrolyte material. Different alcohols (e.g. butanol, ethanol, acetone, acetyl acetone and isopropanol) are used as dispersion medium, the suspension chemistry and subsequent coating of LCO powders by electrophoretic deposition are investigated. A thin and good quality coating of about 11 μm thickness is obtained in an ethanol-based suspension under deposition conditions at 50 V for 2 min. Fuel electrode supported half cells with LCO electrolyte fabricated by electrophoretic deposition and performance test of fabricated cell is evaluated in moist H2 (∼3% H2O) as reducing medium and static air as oxidizing medium.

Synthesis of New Oxopyrimidine and Cyanopyridine Derivatives Containing the Pyrimidine Benzothiazole Moiety with the Evaluating their Colon Anticancer Bioactivity

In this contribution, new derivatives of bicyclic fused rings with bridgehead nitrogen of 3-substituted imidazo/pyrimidine derivatives A1-A3 were synthesized by reacting 2-aminobenzothiazol, acetyl acetone, and different substituted aldehydes in a one-pot reaction. These compounds A1-A3 were then condensed with 4-bromobenzaldehyde and 4-(N,N-dimethylamino)benzaldehyde to form new chalcone derivatives A4-A9. Ring closure of these compounds A4-A9 with urea and malononitrile afforded new oxopyrimidine derivatives A10-A15 and cyanopyridine derivatives A16-A21, respectively. These compounds were characterized by FT-IR, 1H NMR, and 13C NMR spectroscopy. The second part of this work included some of the important applications conducted for these compounds to evaluate their biological activities against colon cancer, which showed excellent results against this disease.

Novel bis pyrimidine-pyrazolone and pyridinyl-4,5-dihydropyrimido[2,1[1]-c,1,2,4]triazepine utilized ultrasonic energy, anti-proliferative activity, docking simulation, and theoretical investigation

Eco-friendly synthesis of novel bis heterocyclic compounds containing pyridine derivatives utilized green tools such as ultrasonication energy. Moreover, the nucleophilic substitution of bis pyrimidine-2-thiol derivatives with hydrazine hydrate in glacial acetic acid in order to form the corresponding bis(hydrazinyl-6-(pyridin-yl)pyrimidin-4-yl) derivatives 3a-c in excellent yield. Furthermore, the latter obtained hydrazinyl pyrimidine derivatives 3a-c can easily be attacked with ethylacetoactate to give bis dihydro-3H-pyrazol-3-one derivatives 5a-c, while the reactivity of acetyl acetone in glacial acetic acid using ultrasonic energy affords the dihydropyrimido[2,1-c][1,2,4]triazepin-9-yl)-5-methyl-1H-1,2,3-triazol-1-yl)benzene derivatives 7a-c, and these compounds were elucidated utilized spectrum analysis. These obtained compounds were exhibited as having antitumor activity against MCF-7 breast and A-549 carcinoma cell lines via neutral red uptake assays, and bis compounds 5c and 7cshowed excellent activity comparable to the doxorubicin drug. Moreover, these biological evaluations were confirmed through molecular docking simulation with PDBID: 4hdq and PDBID:2ito, which showed the least binding affinity with -11.641 and -13.646 kcal/mol, respectively. Also, the theoretical calculation of these bis heterocycles was optimized through the DFT/B3LYP/6-31(G) basis set, which identified their physical descriptors and showed the stability of these bis compounds, confirmed the experimental work with FMO, ESP, and MEP.

Synthesis, photostability and antibacterial activity of a series of symmetrical α,β-unsaturated ketones as potential UV filters

A series of three symmetrical α,β-unsaturated ketones, namely, (1E,4E)-1,5-bis[4-(methylthio)phenyl]penta-1,4-dien-3-one, 1, (1E,4E)-1,5-bis[4-(dimethylamino)phenyl]penta-1,4-dien-3-one, 2, and (1E,4E)-1,5-bis[4-(ethyl)phenyl] penta-1,4-dien-3-one, 3, were synthesized in excellent yields (above 70%) and within a short reaction time (1 h), via an improved Knoevenagel condensation with acetyl acetone and substituted benzaldehydes. All the compounds were fully characterized by UV/Vis, IR, NMR and mass spectrometry. In addition, compound 1 was characterized by single crystal X-ray diffraction. The photostability of the prepared compounds was investigated in solvents of different polarity and proticity by exposure to simulated solar radiation. Three solvents were used, namely, ethyl acetate, dimethylsulfoxide and methanol. The change in UV absorption was monitored by a standard spectrophotometric method and photodegradation products were identified by 1H NMR. According to the results, 1 and 3 were not photostable, and suffered significant changes in their UV absorption spectra. Compound 2, on the other hand, was observed to be considerably photostable in the polar protic solvent methanol but less photostable in the polar aprotic solvent dimethylsulfoxide. All three compounds (1–3) photodegraded appreciably in the less polar aprotic solvent ethyl acetate. Therefore, their photostability is solvent dependent. The antibacterial activity of 1–3 was evaluated by means of the modified broth microdilution method against both gram-negative and gram-positive bacterial strains. Compounds 2 (methylated amine) and 3 (ethyl) have electron-releasing substituents and they were found to have excellent activity against all the tested bacteria. Thus, compounds 2 and 3 can be further explored as potential leads for the development of cheaper, safer, more effective and potent antibiotics against both gram-positive and gram-negative bacterial strains, and compound 2 is a good candidate for use in sunscreen formulations if dissolved in a polar solvent.