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The enzymatic oxidation of polyunsaturated fatty acids, particularly arachidonic acid, produces important lipid mediators such as leukotrienes and prostaglandins, which are critical for triggering inflammatory cascades in the body. The enzyme lipoxygenase‐15 (LOX‐15) plays a crucial role in the oxygenation of unsaturated fatty acids. Targeting this enzyme for inhibition is essential for diminishing inflammation and averting numerous potentially fatal diseases. Therefore, the inhibitory activity of a series of isoniazid derivatives, selected from our in‐house library, was assessed against LOX‐15 by employing both in vitro and in silico methods. Among the 23 compounds evaluated, 15 showed activity in vitro. Notably, compound 7 was the most effective, demonstrating an IC50 value of 1.4±0.1 μM while the standard inhibitor, NDGA, showed an inhibition at 9.4±0.6 μM. These compounds were found to competitively inhibit LOX‐15, with Ki values ranging from 1.2–7.1 μM. Molecular docking was utilized to investigate the intermolecular interactions among the active compounds. The thermodynamic stability of the compound 7 and NDGA in complex with LOX‐15 was verified through 100 ns of molecular dynamics simulations. Post‐simulation analyses involved RMSD, RMSF, RoG, free energy landscape, principal component analysis, and dynamic cross‐correlation matrix. Compound 7 and NDGA had MM/GBSA binding energies of −54.14±2.55 kcal/mol and −35.24±3.23 kcal/mol, respectively. The study underscores the significant potential of isoniazid derivatives in LOX‐15 inhibition and their role in managing inflammatory diseases. [ABSTRACT FROM AUTHOR]

In this paper, we have examined eight new first‐row transition metal complexes (1–8). Mutli‐donor ligands based on barbituric and thiobarbituric acids were used in complexation reactions. The synthesized complexes were analyzed using FT‐IR and UV–vis spectroscopy, elemental (CHN) analysis, and single‐crystal X‐ray diffraction analysis. These complexes exhibited significant urease enzyme inhibition with IC50 values in the range of 13.73 ± 1.08–43.21 ± 1.50 μM. We observed excellent binding orientation of these complexes in the active site of Urease. The molecular docking results correlate well with in vitro observations. [ABSTRACT FROM AUTHOR]

A new compound, commikuanoid D, was isolated from the ethyl acetate fraction of Commiphora kua resin. The structure was unambiguously elucidated on the basis of complete spectroscopic analysis. Furthermore, the compound displayed potent carbonic anhydrase II inhibition with IC50 of 17.4 ± 0.32 μM. On the other hand, the molecular docking reflected that the acetyl group of the molecule specifically binds with the Zn ion at the active site of CA-II, and the OH group of the compound mediated hydrogen bonding with Gln92, thus blocking the enzyme activity with a good binding score (≥ 7 kcal/mol). [ABSTRACT FROM AUTHOR]

Here, we report the synthesis, carbonic anhydrase-II (CA-II) inhibition and structure–activity relationship studies of cinnamaldehyde-clubbed thiosemicarbazones derivatives. The derivatives showed potent activities in the range of 10.3 ± 0.62–46.6 ± 0.62 µM. Among all the synthesized derivatives, compound 3n (IC50 = 10.3 ± 0.62 µM), 3g (IC50 = 12.1 ± 1.01 µM), and 3h (IC50 = 13.4 ± 0.52 µM) showed higher inhibitory activity as compared to the standard inhibitor, acetazolamide. Furthermore, molecular docking of all the active compounds was carried out to predict their behavior of molecular binding. The docking results indicate that the most active hit (3n) specifically mediate ionic interaction with the Zn ion in the active site of CA-II. Furthermore, the The199 and Thr200 support the binding of thiosemicarbazide moiety of 3n, while Gln 92 supports the interactions of all the compounds by hydrogen bonding. In addition to Gln92, few other residues including Asn62, Asn67, The199, and Thr200 play important role in the stabilization of these molecules in the active site by specifically providing H-bonds to the thiosemicarbazide moiety of compounds. The docking score of active hits are found in range of − 6.75 to − 4.42 kcal/mol, which indicates that the computational prediction correlates well with the in vitro results. [ABSTRACT FROM AUTHOR]

Utilizing multi-target drugs shows great promise as an effective strategy against polygenic diseases characterized by intricate patho-mechanisms, such as ulcers, skin dermatitis, and cancers. The current research centers around the creation of hybrid compounds, connecting dibenzazepine and isoxazole, with the aim of exploring their potential as inhibitors for urease and tyrosinase enzymes. Analogs 6a, 6b, 6d, 6 h-6j, and 6 l demonstrated strong inhibitory potential against tyrosinase enzyme with IC 50 values of 4.32 ± 0.31–12.36 ± 0.48. Whereas analogs 6a, 6c, 6e, 6f, 6h-6m, and 6r exhibited potent inhibitory activities against urease enzyme with IC 50 values of 3.67 ± 0.91–15.60 ± 0.18 μM. Furthermore, compounds 6i, 6n, and 6r showed weak toxic effect in BJ-cell line, whereas the remaining compounds were found non-toxic to normal cell line. The mechanistic studies of potent inhibitors of both the enzymes showed competitive mode of inhibition. Molecular docking was employed to establish the relationship between structure and activity and to elucidate the interaction mechanism. This analysis revealed that the active analogs exhibited crucial interactions with the active site residues of urease and tyrosinase, thus corroborating our experimental results. Hence, the generated derivatives of dibenzazepine-linked isoxazoles present intriguing starting points for further investigations into their potential as inhibitors of urease and tyrosinase, with the potential for future modification and enhancement. [ABSTRACT FROM AUTHOR]

Carbonic anhydrase-II (CA-II) is strongly related with gastric, glaucoma, tumors, malignant brain, renal and pancreatic carcinomas and is mainly involved in the regulation of the bicarbonate concentration in the eyes. With an aim to develop novel heterocyclic hybrids as potent enzyme inhibitors, we synthesized a series of twelve novel 3-phenyl-β-alanine 1,3,4-oxadiazole hybrids (4a–l), characterized by 1H- and 13C-NMR with the support of HRESIMS, and evaluated for their inhibitory activity against CA-II. The CA-II inhibition results clearly indicated that the 3-phenyl-β-alanine 1,3,4-oxadiazole derivatives 4a–l exhibited selective inhibition against CA-II. All the compounds (except 4d) exhibited good to moderate CA-II inhibitory activities with IC50 value in range of 12.1 to 53.6 µM. Among all the compounds, 4a (12.1 ± 0.86 µM), 4c (13.8 ± 0.64 µM), 4b (19.1 ± 0.88 µM) and 4h (20.7 ± 1.13 µM) are the most active hybrids against carbonic CA-II. Moreover, molecular docking was performed to understand the putative binding mode of the active compounds. The docking results indicates that these compounds block the biological activity of CA-II by nicely fitting at the entrance of the active site of CA-II. These compounds specifically mediating hydrogen bonding with Thr199, Thr200, Gln92 of CA-II. [ABSTRACT FROM AUTHOR]

In continuation of phytochemical investigations of the methanolic extract of Dictyopteris hoytii, we have obtained twelve compounds (1–12) through column chromatography. Herein, three compounds, namely, dimethyl 2-bromoterepthalate (3), dimethyl 2,6-dibromoterepthalate (4), and (E)-3-(4-(dimethoxymethyl)phenyl) acrylic acid (5) are isolated for the first time as a natural product, while the rest of the compounds (1, 2, 6–12) are known and isolated for the first time from this source. The structures of the isolated compounds were elucidated by advanced spectroscopic 1D and 2D NMR techniques including 1H, 13C, DEPT, HSQC, HMBC, COSY, NEOSY, and HR-MS and comparison with the reported literature. Furthermore, eight compounds (13–20) previously isolated by our group from the same source along with the currently isolated compounds (1–12) were screened against the CA-II enzyme. All compounds, except 6, 8, 14, and 17, were evaluated for in vitro bovine carbonic anhydrase-II (CA-II) inhibitory activity. Eventually, eleven compounds (1, 4, 5, 7, 9, 10, 12, 13, 15, 18, and 19) exhibited significant inhibitory activity against CA-II with IC50 values ranging from 13.4 to 71.6 μM. Additionally, the active molecules were subjected to molecular docking studies to predict the binding behavior of those compounds. It was observed that the compounds exhibit the inhibitory potential by specifically interacting with the ZN ion present in the active site of CA-II. In addition to ZN ion, two residues (His94 and Thr199) play an important role in binding with the compounds that possess a carboxylate group in their structure. [ABSTRACT FROM AUTHOR]

Prolyl endopeptidase or prolyl oligopeptidase (PEP or POP) is highly expressed in brain, and associated with autism spectrum disorders, dementia, aging and various psychological disorders, such as schizophrenia, mania, and neurodegeneration. To design highly potent and novel POP inhibitors, structure-based virtual screening was carried out using pharmacophore modeling and molecular docking studies. The docking based active compounds [incensole (1), incensole acetate (2), incensone (3), incensfuran (4), and epi-incensole acetate (5)] were selected and their dynamic behavior was studied through molecular dynamic simulation. Later, the top-ranked [predicted active, (1–5)] and lower-ranked [predicted in-active, (6–10)] compounds were tested by in-vitro assay. The in-vitro results showed that all top-ranked compounds (1–5) found significantly active against POP enzyme with IC 50 values in range of 3.1 ± 0.45 to 24.4 ± 1.16 μM, while lower-ranked (6–10) were inactive, indicated accuracy of docking results. Kinetics studies on all active compounds 1–5 were carried out to investigate their mode of inhibition and dissociation constants K i. All compounds showed competitive behaviors with K i values in the range of 0.92–8.12 μM. The study resulted in the identification of five (1–5) diterpene based molecules from natural sources that significantly inhibit the activity of POP by competitive mode of inhibition. [ABSTRACT FROM AUTHOR]

Lycium shawii Roem. & Schult and resin of Aloe vera (L.) BURM. F. are commonly used in Omani traditional medication against various ailments. Herein, their antiproliferative and antioxidant potential was explored. Bioassay-guided fractionation of the methanol extract of both plants led to the isolation of 14 known compounds, viz., 1–9 from L. shawii and 10–20 from A. vera. Their structures were confirmed by combined spectroscopic techniques including 1D (1H and 13C) and 2D (HMBC, HSQC, COSY) nuclear magnetic resonance (NMR), and electrospray ionization-mass spectrometry (ESI-MS). The cytotoxic potential of isolates was tested against the triple-negative breast cancer cell line (MDA-MB-231). Compound 5 exhibited excellent antiproliferative activity in a range of 31 μM, followed by compounds 1–3, 7, and 12, which depicted IC50 values in the range of 35–60 μM, while 8, 6, and 9 also demonstrated IC50 values >72 μM. Subsequently, in silico target fishing was applied to predict the most potential cellular drug targets of the active compounds, using pharmacophore modeling and inverse molecular docking approach. The extensive in silico analysis suggests that our compounds may target carbonic anhydrase II (CA-II) to exert their anticancer activities. When tested on CA-II, compounds 5 (IC50 = 14.4 µM), 12 (IC50 = 23.3), and 2 (IC50 = 24.4 µM) showed excellent biological activities in vitro. Additionally, the ethyl acetate fraction of both plants showed promising antioxidant activity. Among the isolated compounds, 4 possesses the highest antioxidant (55 μM) activity followed by 14 (241 μM). The results indicated that compound 4 can be a promising candidate for antioxidant drugs, while compound 5 is a potential candidate for anticancer drugs. [ABSTRACT FROM AUTHOR]

Fourteen triterpene acids, viz., three tirucallane-type (1–3), eight ursane-type (4–11), two oleanane-type (12, 13) and one lupane type (21), along with boswellic aldehyde (14), α-amyrine (15), epi-amyrine (16), straight chain acid (17), sesquiterpene (19) and two cembrane-type diterpenes (18, 20) were isolated, first time, from the methanol extract of Boswellia elongata resin. Compound (1) was isolated for first time as a natural product, while the remaining compounds (2‒21) were reported for first time from B. elongata. The structures of all compounds were confirmed by advanced spectroscopic techniques including mass spectrometry and also by comparison with the reported literature. Eight compounds (1–5, 11, 19 and 20) were further screened for in vitro α-glucosidase inhibitory activity. Compounds 3–5 and 11 showed significant activity against α-glucosidase with IC50 values ranging from 9.9–56.8 μM. Compound 4 (IC50 = 9.9 ± 0.48 μM) demonstrated higher inhibition followed by 11 (IC50 = 14.9 ± 1.31 μM), 5 (IC50 = 20.9 ± 0.05 μM) and 3 (IC50 = 56.8 ± 1.30 μM), indicating that carboxylic acid play a key role in α-glucosidase inhibition. Kinetics studies on the active compounds 3–5 and 11 were carried out to investigate their mechanism (mode of inhibition and dissociation constants Ki). All compounds were found to be non-competitive inhibitors with Ki values in the range of 7.05 ± 0.17–51.15 ± 0.25 µM. Moreover, in silico docking was performed to search the allosteric hotspot for ligand binding which is targeted by our active compounds investigates the binding mode of active compounds and it was identified that compounds preferentially bind in the allosteric binding sites of α-glucosidase. The results obtained from docking study suggested that the carboxylic group is responsible for their biologic activities. Furthermore, the α-glucosidase inhibitory potential of the active compounds is reported here for the first time. [ABSTRACT FROM AUTHOR]

• A novel series of N4 -substitution of cinnamaldehyde with thiosemicarbazones 3a-q were synthesized. • Structures were characterized by FTIR, 1HNMR, 13CNMR and ESI-MS. • All compounds displayed significant urease inhibition with IC 50 values of 11.4 ± 0.23–80.6 µM. • Kinetic studies showed that compound 3o is a competitive inhibitor with ki value 8.65 ± 0.37 µM. • Molecular docking studies were carried out to establish their structure-activity relationship and binding interaction. Hyperactivity of urease enzyme induces pathogenesis of peptic ulcers and gastritis. The excess of urease can be reduced by introducing various inhibitors. The risk of high urease content also partakes in agriculture field where it declines the environmental health. This alarming situation leads to the mandatory quest of such novel scaffolds that must work wonders in the field of medicinal chemistry. Consequently, we herein report a novel series of N4 -substitution of cinnamaldehyde with thiosemicarbazones 3a-q as potential candidates for urease inhibition. These new N4 -substituted thiosemicarbazones 3a-q of indistinct chemical scaffolds were characterized by advanced spectroscopic techniques, such as ESI-MS, 13CNMR, 1HNMR, and FTIR. All newly synthesized compounds showed significant urease inhibitions with IC 50 values in range of 11.4 ± 0.23 to 80.6 ± 0.52 μM. Furthermore, kinetic studies of compound 3o displayed competitive type of inhibition with ki value 8.65 ± 0.37 µM. For analysis of structure‒activity relationship and interactions pattern of all compounds, molecular docking was used, which revealed excellent binding interactions of compounds with the active site residues, such as nickel atom coordination, π–cation, π–π interactions, and hydrogen bonding. Additionally, the predicted pharmacokinetics and drug-likeness of compounds suggest that these compounds have good pharmacokinetic and physicochemical properties, and these compounds follow rules of drug-likeness. [ABSTRACT FROM AUTHOR]

• Synthesis of amantadine derivatives was carried out using ultra sonication method. • Synthesized analogs were evaluated for their urease, and α-glucosidase enzyme inhibition activities. • Molecular docking was performed in order to predict the binding interactions with respective enzymes. • Potent inhibitors of urease and α-glucosidase enzyme were obtained. • Kinetic studies were carried out to determine the mode of inhibition. Ultrasonic synthesis of 26 amantadine derivatives, (3-28) including seven new compounds, are reported with significantly reduced synthesis time and increased percentage yield relative to literature data. Evaluation of the urease, and α-glucosidase enzyme inhibitory activities of all amantadine derivatives are being reported here for the first time. Three compounds were found to be potent urease inhibitors (IC 50 = 9.32 ± 1.01 µM, to IC 50 = 11.32 ± 1.05 µM) as compared to the standard drug acetohydroxamic acid (IC 50 = 20.3 ± 0.4 µM). Five compounds were found to be potent inhibitors of α-glucosidase (IC 50 = 40.63 ± 1.70, to 50.07 ± 1.73) as compared to standard drug acarbose (IC 50 = 875.75 ± 2.08 µM). Kinetic studies were performed to investigate competitive and non-competitive inhibition of α-glucosidase enzymes and mixed type inhibition of urease enzyme. All compounds along with parent drug was checked for their cytotoxicity against human fibroblast (B.J.) cell line. Four compounds were found to be toxic, while the rest were nontoxic. Furthermore, in silico studies were performed to predict the binding interactions of the compounds at the active site of the enzymes. The two most active adamantane analogs against urease are those with m- and o-fluoro substitution due to specific interactions with CME592, HOH1918 and GLN635 (3.04, 2.74, and 3.21 Å). Ortho analogs interact with GLN635 (3.04, 3.10 Å). The two analogs having diflouro and tri flouro methyl group, showed a slight lower activity as compared to the first two compounds. This analysis clearly indicates the importance of position of fluoro group in urease inhibition activity. Similarly, in α-glucosidase inhibitors, three compounds with p-OCH 3, ethyl groups, and di-fluoro were found to be the most active inhibitors in excellent agreement with experimental data. This study identifies new analogs with potent α-glucosidase and urease inhibitory activities. and, thus, may be of therapeutic importance. [Display omitted] [ABSTRACT FROM AUTHOR]

In several types of cancers, the expression of carbonic anhydrase-IX (CA-IX) enzyme is elevated than its normal level which ultimately plays a key role in the tumor growth of epithelial cells in breast and lung cancer by acidifying tumor microenvironment, therefore, inhibition of this target is important in antitumor therapy. We have synthesized bis -benzimidazole derivatives (1–25) by using 3,3′-diaminobenzidine and various aromatic aldehydes and characterized by various spectroscopic methods (UV/Visible, 1HNMR, 13CNMR, and mass spectrometry). Their inhibitory potential for human CA-IX (h CA-IX) was evaluated in-vitro , where several synthesized derivatives showed potent inhibition of h CA-IX (IC 50 values in range of 5.23 ± 1.05 to 40.10 ± 1.78 μM) and compounds 3–5 , 7–8 , 13–16 , 21 and 23 showed superior activity than the standard drug "acetazolamide" (IC 50 = 18.24 ± 1.43 μM). Furthermore, all these compounds showed no toxicity on human fibroblast cell lines (BJ cell lines). Moreover, molecular docking was carried out to predict their binding modes in the active site of CA-IX and revealed a significant role of imidazole ring of synthesized entities in their effective binding with the specific residues of CA-IX. The obtained results paved the way for further in vivo and other pharmacological studies for the optimization of these molecules as possible anti-cancer agents. [ABSTRACT FROM AUTHOR]

Three new cycloartane triterpenoids, commikuanoids A-C (1 – 3), together with four known compounds 4 – 7 , were isolated from the resin of Commiphora kua. Their structures were confirmed by advanced NMR techniques such as 1D (1H and 13C) and 2D (HMBC, HSQC, COSY, NOESY and NOE) and high-resolution mass spectrometry (HRMS). Five compounds (1 – 5) were screened for in vitro carbonic anhydrase II (CA II) inhibitory activity. All the tested compounds demonstrated significant activity against CA II with IC 50 values ranging from 4.9–19.6 μM. Moreover, the binding pattern of each compound in the binding site of CA-II was predicted through in silico molecular docking approach. It was observed that compounds 2 , 4 , and 5 binds with the Zn ion present in the active site of CA II, while compounds 1 and 3 mediated hydrogen bonding with Thr199 of CA-II, and all the compounds showed good binding score (> − 5 kcal/mol). [Display omitted] [ABSTRACT FROM AUTHOR]