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Background and the purpose of the studyBoswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative.Methods4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-β-boswellic acid; 2, 3-O-acetyl-11-hydroxy-β-boswellic acid; 3. 3-O- acetyl-11-keto-β-boswellic acid and 4, 11-keto-β-boswellic acid. Their inhibitory activity on Jack bean urease were evaluated. Docking and pharmacophore analysis using AutoDock 4.2 and Ligandscout 3.03 programs were also performed to explain possible mechanism of interaction between isolated compounds and urease enzyme.ResultsIt was found that compound 1 has the strongest inhibitory activity against Jack bean urease (IC50 = 6.27 ± 0.03 μM), compared with thiourea as a standard inhibitor (IC50 = 21.1 ± 0.3 μM).ConclusionThe inhibition potency is probably due to the formation of appropriate hydrogen bonds and hydrophobic interactions between the investigated compounds and urease enzyme active site and confirms its traditional usage.

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Telomere maintenance is a universal cancer hallmark, and small molecules that disrupt telomere maintenance generally have anticancer properties. Since the vast majority of cancer cells utilize telomerase activity for telomere maintenance, the enzyme has been considered as an anticancer drug target. Recently, rational design of telomerase inhibitors was made possible by the determination of high resolution structures of the catalytic telomerase subunit from a beetle and subsequent molecular modeling of the human telomerase complex. A hybrid strategy including docking, pharmacophore-based virtual screening, and molecular dynamics simulations (MDS) were used to identify new human telomerase inhibitors. Docking methodology was applied to investigate the ssDNA telomeric sequence and two well-known human telomerase inhibitors' (BIBR1532 and MST-312) modes of interactions with hTERT TEN domain. Subsequently molecular dynamic simulations were performed to monitor and compare hTERT TEN domain, TEN-ssDNA, TEN-BIBR1532, TEN-MST-312, and TEN-ssDNA-BIBR1532 behavior in a dynamic environment. Pharmacophore models were generated considering the inhibitors manner in the TEN domain anchor site. These exploratory studies identified several new potent inhibitors whose IC50 values were generated experimentally in a low micromolar range with the aid of biochemical assays, including both the direct telomerase and the telomeric repeat amplification protocol (TRAP) assays. The results suggest that the current models of human telomerase are useful templates for rational inhibitor design.

Epidermal growth factor receptor (EGFR) is a tyrosine kinase with a key role in cell proliferation, death and differentiation. Mutations in EGFR, including substitution of Thr790 by methionine and Leu858 by arginine (T790M/L858R), lead to a lung cancer that is resistant against first generation inhibitors. In fact, second generation inhibitors were developed, but they proved to have had severe side effects because of the significant potency to suppress the wild type protein just as much. To resolve the problem, a step-by-step rational virtual screening was employed over almost sixty million compounds of PubChem Compound Database to filter out selective inhibitor(s) of T790M/L858R subtype. Consequently, the compound CID 133077 was observed, an active metabolite of Axitirome and also a cholesterol lowering prodrug. Selecting this compound can be explained by the oxamic acid part of molecule. Hence, administration of Axitirome or other compounds which contain oxamic acid is suggested in cases with EGFR T790M/L858R drug resistance.