Supaluk Prachayasittikul

Highlights: • 8-Aminoquinoline-based sulfonamide derivatives ( 3 - 13 ) displayed antioxidant and antimicrobial activities. • Significant descriptors influencing bioactivities were explored. • Computational methods were used to construct predictive (QSAR and QSPR) models. • In silico rational design of new 84 structurally modified compounds were generated. • Potential newly designed compounds with the most promising predicted were highlighted.

Sulfonamide‐based compounds have been a clinically attractive scaffold for drug development and proven as antioxidant and antimicrobial agents, but their pharmacological derivatives containing anthranilates (SA 1–4 ) and therapeutic targets are not clearly clarified. To unravel the neuroprotective roles and underlying mechanisms of SA 1–4 against oxidative injury and healthy longevity crosstalk, a combination of in vitro experiments, in silico modeling, and network pharmacology was employed. Pretreatment with SA 1–4 in human neuronal SH‐SY5Y cells significantly regulated sirtuins (SIRTs)/forkhead box class O 3a (FOXO3a)‐mediated longevity signaling pathway via targeting endogenous antioxidant enzymes (i.e., superoxide dismutase 2 [SOD2] and catalase [CAT]), apoptotic cascades (i.e., Bcl‐2‐associated X‐protein [BAX] and B‐cell lymphoma‐2 [BCL‐2]), mitochondrial balance, and ultimately led to the neuronal rescue. Molecular docking simulations support the possibility of the SA 1–4 modulatory effect within the active binding site of SIRT1. Importantly, in silico predictions of pharmacokinetic profiles suggested that the synthetic compounds possessed preferable drug‐like properties, good oral bioavailability, and safety profiles. Network pharmacology also revealed the involvement of SA 1–4 and key targets‐regulated SIRTs in neurodegeneration, including non‐amyloidogenic cascade, tau phosphorylation, calcium homeostasis, insulin‐mediated glucose uptake, and neuroinflammation. Therefore, SA 1–4 exert promising multi‐target therapeutic strategies against oxidative damage, potentially offering alternative anti‐Alzheimer candidates for further clinical neurodegenerative and anti‐aging therapeutics. image

Terpinen-4-ol (TP4O) is a key monoterpene alcohol commonly used as a quality and authenticity marker in essential oils, cosmetics, herbal products, and pharmaceutical formulations. However, reliable and comparable quantification of TP4O across laboratories is challenged by variability in natural matrices and the limited availability of well-characterized, traceable reference materials. In this study, a high-purity certified reference material (CRM) of TP4O was developed and characterized by the National Institute of Metrology (Thailand). The material’s purity was determined using two independent and complementary approaches: a mass balance method (MB) method based on gas chromatography with flame ionization detection (GC-FID), Karl Fischer coulometric titration (KFT), and thermogravimetric analysis (TGA), and a quantitative ¹H NMR (qNMR) method employing DSS-d₆ as an internal standard. The purity values obtained using the MB (98.41 ± 0.09%) and qNMR (99.13 ± 0.94%) methods were statistically equivalent (p > 0.05). Based on the combined evaluation, a certified purity value of 98.77% with an expanded uncertainty of 3.05% (k = 2) was assigned. Homogeneity and short- and long-term stability assessments confirmed the suitability of the material for its intended use. This TP4O CRM provides an SI-traceable, high-purity reference to support calibration, method validation, and quality assurance in analytical applications involving essential oil components.

Antioxidant compounds have gained current interest as potential protective agents for several therapeutic applications. Antimicrobial drug resistance and infectious diseases also still be concerning globally health issues. Accordingly, the discovery of new antioxidative and antimicrobial agents is essential for human well-being. Thiazole and sulfonamide are privileged scaffolds in drug discovery due to their various bioactive properties. In this study, a series of 2-aminothiazole sulfonamide derivatives (1-12) were synthesized and investigated for their antioxidant (i.e., DPPH and SOD-mimic) and antimicrobial activities. Among tested compounds, compound 8 was the most promising one with potent DPPH and SOD (%DPPH = 90.09 %, %SOD = 99.02 %). However, none of these compounds are active antimicrobial agents. Quantitative structure-activity relationship (QSAR) modeling was performed in which the key findings were further used to guide the rational design of additional derivatives. Two antioxidant QSAR models (i.e., DPPH and SOD) were constructed using multiple linear regression (MLR) with good predictive performance. An additional set of structurally modified compounds were designed based on QSAR findings to finally obtain 112 newly designed compounds in which their activities (DPPH and SOD) were predicted. Most of the modified compounds performed better activities than their prototypes. Mass, polarizability, electronegativity, the presence of C-F bond, van der Waals volume, and structural symmetry were revealed as key properties influencing antioxidant activities. In summary, this study demonstrated the combination used of chemical synthesis, experimental assays, and computer-aided drug design for developing novel antioxidants for potential medicinal applications.

Osteoanabolic agents, or drugs that promote bone formation, have gained considerable attention for osteoporosis management due to their curative and preventive potentials. Sphingosine-1-phosphate receptor 2 (S1PR2) is an attractive drug target, in which its activation leads to osteogenesis-promoting effect. Nitrogen-containing heterocyclic scaffolds (i.e., quinoxaline and indole) are promising pharmacophores possessing diverse bioactivities and were reported as S1PR2 activators. Quantitative structure-activity relationship (QSAR) modeling is a computational approach well-known as a fundamental tool for facilitating successful drug development. This study demonstrates the discovery of new S1PR2 activators using computational-driven rational design. Herein, an original dataset of nitrogen-containing S1PR2 activators was collected from ChEMBL database. The retrieved dataset was separated into two datasets according to their core scaffolds (i.e., quinoxaline and indole). QSAR modeling was performed using multiple linear regression (MLR) algorithm to successfully obtain two models with good predictive performance. The constructed models also revealed key properties playing essential roles for potent S1PR2 activation, such as Van der Waals volume (R2v+ and E3v), mass (MATS5m and Km), electronegativity (H3e), and number of 5-membered rings (nR05). Subsequently, the constructed models were further employed to guide rational design and predict S1PR2 activating effects of an additional set of 752 structurally modified compounds. Most of the modified compounds were predicted to have higher potency than their parents, and a set of promising potent newly designed compounds was highlighted. Additionally, drug-likeness prediction was performed to reveal that most of the newly designed compounds are druggable compounds with possibility for further development.

A series of sixteen acetamidosulfonamide derivatives (1-16) have been synthesized and investigated for their antioxidant (radical scavenging and superoxide dismutase (SOD)) and antimicrobial activities. Most compounds exhibited antioxidant activities in which compound 15 displayed the most potent radical scavenging and SOD activities. Quantitative structure-activity relationship (QSAR) has been studied using multiple linear regression. The constructed QSAR models displayed high correlation coefficient (Q2/Loo-CV= 0.9708 and 0.8753 for RSA and SOD activities, respectively), but low root mean square error (RMSELOO-CV = 0.5105 and 1.3571 for RSA and SOD activities, respectively). The structure-activity relationship showed that an ethylene group connected to pyridine ring provided significant antioxidant activities. The QSAR models give insight into the rational designed of eighty new sulfonamides with various electron donating and withdrawing groups. The top five new designed sulfonamides with nitro group are potential antioxidants to be further developed for medicinal applications.