A pharmacophore model for sulphonyl-urea (-cyanoguanidine) compounds with dual action, thromboxane receptor antagonists and thromboxane synthase inhibitors

Synthesis and evaluation of α-glucosidase inhibitory activity of sulfonylurea derivatives

Two series of sulfonylureas derivatives including 24 compounds (4, 7, 5a–5o, 8a–8h), among them 17 new derivatives, have been synthesized and evaluated for their α-glucosidase inhibitory activity. Compounds 5c, 5h and 8e showed significant in vitro α-glucosidase inhibition with IC50 values of 5.58, 79.85 and 213.36 µm, respectively, comparing with the standard compounds acarbose (IC50 = 268.29 µm) and glipizide (IC50 = 300.47 µm). The preliminary structure-activity relationships (SARs) of the synthesized compounds were also investigated.

Human cytochrome P450 enzymes 5-51 as targets of drugs and natural and environmental compounds: mechanisms, induction, and inhibition - toxic effects and benefits

Cytochrome P450 (P450, CYP) enzymes have long been of interest due to their roles in the metabolism of drugs, pesticides, pro-carcinogens, and other xenobiotic chemicals. They have also been of interest due to their very critical roles in the biosynthesis and metabolism of steroids, vitamins, and certain eicosanoids. This review covers the 22 (of the total of 57) human P450s in Families 5-51 and their substrate selectivity. Furthermore, included is information and references regarding inducibility, inhibition, and (in some cases) stimulation by chemicals. We update and discuss important aspects of each of these 22 P450s and questions that remain open.

Synthesis of Novel 1-(4-Substituted pyridine-3-sulfonyl)-3-phenylureas with Potential Anticancer Activity

A series of novel 4-substituted-N-(phenylcarbamoyl)-3-pyridinesulfonamides 11–27 have been synthesized by the reaction of 4-substituted pyridine-3-sulfonamides 2–10 with the appropriate aryl isocyanates in presence of potassium carbonate. The in vitro anticancer activity of compounds 11, 12, 14–21 and 24–26 was evaluated at the U.S. National Cancer Institute and in light of the results, some structure-activity relationships were discussed. The most prominent compound, N-[(4-chlorophenyl)carbamoyl]-4-[4-(3,4-dichlorophenyl)piperazin-1-yl]pyridine-3-sulfonamide (21) has exhibited a good activity profile and selectivity toward the subpanels of leukemia, colon cancer and melanoma, with average GI₅₀ values ranging from 13.6 to 14.9 µM.

In silico design of a dual TPR/TxS inhibitor for venous thromboembolism and related cardiovascular diseases

In recent years, many research efforts have been directed towards preventing vasoconstrictor and platelet aggregatory properties of TxA2related to the prostaglandin cycle, as TxA2has been implicated directly or indirectly in pathologies such as cardiovascular diseases, venous thromboembolism, and pulmonary embolism. The TxA2antagonists and TxS inhibitors undergoing clinical trials have not shown the expected clinical efficacy. This molecular modeling and docking study explains how efficacy may be enhanced by a careful design of multitarget drugs producing synergistic effects simultaneously at different targets. A dual TPR/TxS inhibition strategy is expected to give better clinical efficacy. This study also emphasizes the importance of designing efforts based on detailed analysis of drug−receptor interactions at both targets. Ab initio HF/6-31G(d) and B3LYP/6-31G(d) molecular orbital calculations coupled with flexible ligand docking studies have led to the design of a dual TPR/TxS inhibitor starting from a naturally occurring compound bromelain, derived from pineapple extract with some known pharmacological advantages. A designed lead compound may prove to be a fruitful starting point for the development of clinically efficient drugs for venous thromboembolism and related cardiovascular diseases.

3D pharmacophore models for thromboxane A(2) receptor antagonists

Thromboxane A(2) (TXA(2)) is an endogenous arachidonic acid derivative closely correlated to thrombosis and other cardiovascular diseases. The action of TXA(2) can be effectively inhibited with TXA(2) receptor antagonists (TXRAs). Previous studies have attempted to describe the interactions between the TXA(2) receptor and its ligands, but their conclusions are still controversial. In this study, ligand-based computational drug design is used as a new and effective way to investigate the structure-activity relationship of TXRAs. Three-dimensional pharmacophore models of TXRAs were built with HypoGenRefine and HipHop modules in CATALYST software. The optimal HypoGenRefine model was developed on the basis of 25 TXRAs. It consists of two hydrophobic groups, one aromatic ring, one hydrogen-bond acceptor and four excluded volumes. The optimal HipHop model contains two hydrophobic groups and two hydrogen-bond acceptors. These models describe the key structure-activity relationship of TXRAs, can predict their activities, and can thus be used to design novel antagonists.

Structure-based pharmacophore of COX-2 selective inhibitors and identification of original lead compounds from 3D database searching method

A four-point pharmacophore of COX-2 selective inhibitors was derived from a training set of 16 compounds, using the Catalyst program. It consists of a H bond acceptor, two hydrophobic groups and an aromatic ring, in accordance with SAR data of the compounds and with topology of the COX-2 active site. This hypothesis, combined with exclusion volume spheres representing important residues of the COX-2 binding site, was used to virtually screen the Maybridge database. Eight compounds were selected for an in vitro enzymatic assay. Five of them show COX-2 inhibition close to that of nimesulide and rofecoxib, two reference COX-2 selective inhibitors. As a result, structure-based pharmacophore generation was able to identify original lead compounds, inhibiting the COX-2 isoform.