Synthesis, characterization, and antibacterial activities of novel sulfonamides derived through condensation of amino group containing drugs, amino acids, and their analogs

Comparative study on Antibacterial efficacy of a series of chromone sulfonamide derivatives against drug-resistant and MDR-isolates

Sulfonamide derivatives have numerous pharmaceutical applications having antiviral, antibacterial, antifungal, antimalarial, anticancer, and antidepressant activities. The structural flexibility of sulfonamide derivatives makes them an excellent candidate for the development of new multi-target agents, although long-time exposure to sulfonamide drugs results in many toxic impacts on human health. However, sulfonamides may be functionalized for developing less toxic and more competent drugs. In this work, sulfonamides including Sulfapyridine (a), Sulfathiazole (b), Sulfamethoxazole (c), and Sulfamerazine (d) are used to synthesize Schiff bases of 7-hydroxy-4-methyl-2-oxo-2H-chromene-8-carbalde-hyde (1a-1d). The synthesized compounds were spectroscopically characterized and tested against hospital isolates of three Gram-positive (Methicillin-resistant Staphylococcus aureus PH217, Ampicillin-resistant Coagulase-negative Staphylococcus aureus, multidrug-resistant (MDR) Enterococcus faecalis PH007R) and two Gram-negative bacteria (multidrug-resistant Escherichia coli, and Salmonella enterica serovar Typhi), compared to the quality control strains from ATCC (S. aureus 29213, E. faecalis 25922, E. coli 29212) and MTCC (S. Typhi 734). Two of the four Schiff bases 1a and 1b are found to be more active than their counterpart 1c and 1d; while 1a have showed significant activity by inhibiting MRSA PH217 and MDR isolates of E. coli at the minimum inhibitory concentration (MIC) of 150 μg/mL and 128 μg/mL with MBC of 1024 µg/mL, respectively. On the other hand, the MIC of 1b was 150 μg/mL against both S. aureus ATCC 29213 and Salmonella Typhi MTCC 734, compared to the control antibiotics Ampicillin and Gentamycin. Scanning electron microscopy demonstrated the altered surface structure of bacterial cells as a possible mechanism of action, supported by the in-silico molecular docking analysis.

Acetylsalicylic acid-sulfa drugs conjugates as potential urease inhibitors and anti-inflammatory agents: bio-oriented drug synthesis, molecular docking, and dynamics simulation studies

To explore the new mode of action and reduce side effects, making conjugates of existing drugs is becoming an attractive tool in the realm of medicinal chemistry. In this work, we exploited this approach and synthesized new conjugates to assess their activities against the enzymes involved in different pathological conditions. Specifically, we design and synthesized conjugates involving acetylsalicylic acid and sulfa drugs, validating the newly crafted conjugates using techniques like IR, 1HNMR, 13CNMR, and elemental analysis. These conjugates underwent assessment for their ability to inhibit cyclooxygenase-2 (COX-2), urease enzymes, and their anti-inflammatory potential. A competitive mode of urease inhibition was observed for acetylsalicylic acid conjugated with sulfanilamide, sulfacetamide, and sulfadiazine with IC50 of 2.49 ± 0.35 µM, 6.21 ± 0.28 µM, and 6.57 ± 0.44 µM, respectively. Remarkably, the acetylsalicylic acid-sulfamethoxazole conjugate exhibited exceptional anti-inflammatory activity, effectively curtailing induced edema by 83.7%, a result akin to the reference anti-inflammatory drug indomethacin's performance (86.8%). Additionally, it demonstrated comparable COX-2 inhibition (75.8%) to the reference selective COX-2 inhibitor celecoxib that exhibited 77.1% inhibition at 10 µM concentration. To deepen our understanding, we employed molecular docking techniques to predict the binding interactions of competitive inhibitors with COX-2 and urease receptors. Additionally, MD simulations were carried out, confirming the stability of inhibitor-target complexes throughout the simulation period, devoid of significant conformational changes. Collectively, our research underscores the potential of coupling approved medicinal compounds to usher in novel categories of pharmacological agents, holding promise for addressing a wide spectrum of pathological disorders involving COX-2 and urease enzymes.Communicated by Ramaswamy H. Sarma.

Exploring the potential of propanamide-sulfonamide based drug conjugates as dual inhibitors of urease and cyclooxygenase-2: biological and their in silico studies

Derivative synthesis has been a crucial method for altering the effects of already-approved medications, especially to lessen adverse effects and enhance results. Making use of this multi-target approach, a series of naproxen-sulfa drug conjugates was designed and synthesized. The newly designed conjugates were confirmed by spectroscopic techniques like IR, 1HNMR, 13CNMR, and elemental analysis. The conjugates were screened for anti-inflammatory, urease, and cyclooxygenase-2 (COX-2) inhibition. Naproxen conjugated with sulfanilamide, sulfathiazole, and sulfaguanidine was found potent and showed a competitive mode of urease inhibition, with IC50 (µM) values 6.69 ± 0.11, 5.82 ± 0.28, 5.06 ± 0.29, respectively. When compared to other screened conjugates, the naproxen-sulfamethoxazole conjugation showed better anti-inflammatory action by inhibiting induced edema by 82.8%, which is comparable to the medication indomethacin (86.8% inhibition). Whereas it exhibited 75.4% inhibition of COX-2 at 10 µM concentration which is comparable with the reference drug (celecoxib, 77.1% inhibition). Moreover, the binding modes of competitive inhibitors with the urease and COX-2 receptor were predicted through molecular docking studies and their stability analysis through MD simulations showed that these compounds made stable complexes with the respective targets and there were no conformational changes that occurred during simulation. The obtained results showed that the conjugates of approved therapeutic molecules may lead to the development of novel types of pharmacological agents in the treatment of several pathological disorders where urease and COX-2 enzymes are involved.

New Acetamide-Sulfonamide-Containing Scaffolds: Antiurease Activity Screening, Structure-Activity Relationship, Kinetics Mechanism, Molecular Docking, and MD Simulation Studies

The development of novel scaffolds that can increase the effectiveness, safety, and convenience of medication therapy using drug conjugates is a promising strategy. As a result, drug conjugates are an active area of research and development in medicinal chemistry. This research demonstrates acetamide-sulfonamide scaffold preparation after conjugation of ibuprofen and flurbiprofen with sulfa drugs, and these scaffolds were then screened for urease inhibition. The newly designed conjugates were confirmed by spectroscopic techniques such as IR, 1HNMR, 13CNMR, and elemental analysis. Ibuprofen conjugated with sulfathiazole, flurbiprofen conjugated with sulfadiazine, and sulfamethoxazole were found to be potent and demonstrated a competitive mode of urease inhibition, with IC50 (µM) values of 9.95 ± 0.14, 16.74 ± 0.23, and 13.39 ± 0.11, respectively, and urease inhibition of 90.6, 84.1, and 86.1% respectively. Ibuprofen conjugated with sulfanilamide, sulfamerazine, and sulfacetamide, whereas flurbiprofen conjugated with sulfamerazine, and sulfacetamide exhibited a mixed mode of urease inhibition. Moreover, through molecular docking experiments, the urease receptor-binding mechanisms of competitive inhibitors were anticipated, and stability analysis through MD simulations showed that these compounds made stable complexes with the respective targets and that no conformational changes occurred during the simulation. The findings demonstrate that conjugates of approved therapeutic molecules may result in the development of novel classes of pharmacological agents for the treatment of various pathological conditions involving the urease enzyme.

Synthesis and Antimicrobial Activity of New Heteroaryl(aryl) Thiazole Derivatives Molecular Docking Studies

Herein, we report the design, synthesis, and evaluation of the antimicrobial activity of new heteroaryl (aryl) thiazole derivatives. The design was based on a molecular hybridization approach. The in vitro evaluation revealed that these compounds demonstrated moderate antibacterial activity. The best activity was achieved for compound 3, with MIC and MBC in the range of 0.23–0.7 and 0.47–0.94 mg/mL, respectively. Three compounds (2, 3, and 4) were tested against three resistant strains, namely methicillin resistant Staphylococcus aureus, P. aeruginosa, and E. coli, which showed higher potential than the reference drug ampicillin. Antifungal activity of the compounds was better with MIC and MFC in the range of 0.06–0.47 and 0.11–0.94 mg/mL, respectively. The best activity was observed for compound 9, with MIC at 0.06–0.23 mg/mL and MFC at 0.11–0.47 mg/mL. According to docking studies, the predicted inhibition of the E. coli MurB enzyme is a putative mechanism of the antibacterial activity of the compounds, while inhibition of 14a-lanosterol demethylase is probably the mechanism of their antifungal activity.

Triazolo Based-Thiadiazole Derivatives. Synthesis, Biological Evaluation and Molecular Docking Studies

The goal of this research is to investigate the antimicrobial activity of nineteen previously synthesized 3,6-disubstituted-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole derivatives. The compounds were tested against a panel of three Gram-positive and three Gram-negative bacteria, three resistant strains, and six fungi. Minimal inhibitory, bactericidal, and fungicidal concentrations were determined by a microdilution method. All of the compounds showed antibacterial activity that was more potent than both reference drugs, ampicillin and streptomycin, against all bacteria tested. Similarly, they were also more active against resistant bacterial strains. The antifungal activity of the compounds was up to 80-fold higher than ketoconazole and from 3 to 40 times higher than bifonazole, both of which were used as reference drugs. The most active compounds (2, 3, 6, 7, and 19) were tested for their inhibition of P. aeruginosa biofilm formation. Among them, compound 3 showed significantly higher antibiofilm activity and appeared to be equipotent with ampicillin. The prediction of the probable mechanism by docking on antibacterial targets revealed that E. coli MurB is the most suitable enzyme, while docking studies on antifungal targets indicated a probable involvement of CYP51 in the mechanism of antifungal activity. Finally, the toxicity testing in human cells confirmed their low toxicity both in cancerous cell line MCF7 and non-cancerous cell line HK-2.

Sulfonamide drugs: structure, antibacterial property, toxicity, and biophysical interactions

Sulfonamide (or sulphonamide) functional group chemistry (SN) forms the basis of several groups of drug. In vivo sulfonamides exhibit a range of pharmacological activities, such as anti-carbonic anhydrase and anti-t dihydropteroate synthetase allowing them to play a role in treating a diverse range of disease states such as diuresis, hypoglycemia, thyroiditis, inflammation, and glaucoma. Sulfamethazine (SMZ) is a commonly used sulphonamide drug in veterinary medicine that acts as an antibacterial compound to treat livestock diseases such as gastrointestinal and respiratory tract infections. Sulfadiazine (SDZ) is another frequently employed sulphonamide drug that is used in combination with the anti-malarial drug pyrimethamine to treat toxoplasmosis in warm-blooded animals. This study explores the research findings and the work behaviours of SN (SMZ and SDZ) drugs. The areas covered include SN drug structure, SN drug antibacterial activity, SN drug toxicity, and SN environmental toxicity.

Cephalosporin Conjugated Sulfonamides: Synthesis, Characterization and Anticancer Activities

Background:

In the present study, eight new cephalosporin conjugated sulfonamides were synthesized to investigate the anticancer activity.

Methods:

All the compounds were characterized on the basis of FTIR, 1HNMR, MS and elemental analysis (CHN). The new compounds were evaluated against the Vero and Hep G2 cancer cell lines for their anticancer activities. Cytotoxicity of all the compounds was determined against brine shrimp at 20 μg concentration.

Results and Conclusion:

The results revealed that ceftriaxone conjugated sulfonamide was the most potent and showed cytotoxicity (86.4 %) comparable to the standard reference drug actinomycin D (90.0 %). The compounds with lower cLogP value showed more antiproliferative effect due to their higher cell permeability. Ceftriaxone conjugated with 4-acetamido benzene sulfonyl was the most active compound against both cell lines with IC50 3.95 μM (Vero) and 5.11 μM (Hep G2) values whereas its activity was comparable with 5-fluorouracil used as reference drug (IC50 = 2.84 μM).

Amidine Sulfonamides and Benzene Sulfonamides: Synthesis and Their Biological Evaluation

New amidine and benzene sulfonamide derivatives were developed and structures of the new products were confirmed by elemental and spectral analysis (FT-IR, ESI-MS,1HNMR, and13CNMR). In vitro, developed compounds were screened for their antibacterial and antifungal activities against medically important bacterial strains, namely,S. aureus, B. subtilis, andE. coli, and fungi, namely,A. flavus, A. parasiticus, andA.sp. The antibacterial and antifungal activities have been determined by measuring MIC values (μg/mL) and zone of inhibitions (mm). Among the tested compounds, it was found that compounds3b,9a, and9bhave most potent activity againstS. aureus, A. flavus, and A. parasiticus, respectively, and were found to be more active than sulfamethoxazole and itraconazole with MIC values 40 μg/mL. In contrast, all the compounds were totally inactive against theA.sp. except10band15bto show activity to some extent.