These results suggest that the molecular flexibility given by the alkyl spacers allows a better fit to the enzymes active site, including formation of a new hydrogen relationship by the second urea group

These results suggest that the molecular flexibility given by the alkyl spacers allows a better fit to the enzymes active site, including formation of a new hydrogen relationship by the second urea group. hypertension, inflammatory diseases and pain.8C10 Small N,N-disubstituted symmetric ureas, such as 1,3-dicyclohexyl urea, were found to be very potent inhibitors of sEH.11C15 However, because of their strong crystalline lattice, these kinds of compounds have poor solubility in many solvents. To improve solubility, asymmetric ureas having a flexible side chain, such as AUDA (12-(3-adamantylureido)-dodecanoic acid), were tested and found to be potent sEH inhibitors. While this class of sEH inhibitor shows biological effects when tested without careful formulation.16,17 Therefore, to CID 2011756 improve the metabolic stability, a third class of conformationally restricted inhibitors, such as AEPU (1-adamantyl-3-(1-acetylpiperidin-4-yl)-urea) or em t /em -AUCB ( em trans /em -4-((4-(3-adamantylureido)-cyclohexyl)oxy)-benzoic acid), were designed. This latest series includes very potent and more metabolically stable sEH inhibitors that enable in vivo studies. However, these compounds have in general poor solubility, and are quite expensive to synthesize since several steps (3 to 5 5) are required. Here, we statement the screening of symmetric di-ureas that are simpler to obtain as sEH inhibitors. As demonstrated on Number 1, a flexible chain was integrated at the CID 2011756 center of the molecules to improve physical properties, while adamantane and urea organizations Rabbit polyclonal to ACTBL2 were placed at both ends of the molecules to protect the central flexible chain from metabolism, and to provide the additional possibility of hydrogen bonding to improve potency and solubility. Open in a separate window Number 1 General structure of synthesized diureas As explained on plan 1, two simple (one step) and complementary methods were used to obtain the desired compounds in high yield ( 95%). Commercially available 1-isocyanatemethyl adamantane or numerous adamantyl comprising isocyanates18 were reacted with numerous amines comprising 2, 4, 6 or 8 carbons that are usually used in supramolecular chemistry as guest-monomers.19C21. To vary the XCparameter, several commercially available hydrochlorides of amines were reacted with alkyl di-isocyanates. Compounds comprising phenyl and piperidine rings between the urea groups were synthesized as well because those organizations generally confer properties found to be handy in medicinal chemistry.22C24 Constructions of the acquired chemicals were assessed by NMR, while purity was assessed by mass spectrometry and elemental analysis (observe supplemental materials for details). Open in a separate window Plan 1 Reagents and conditions: (a) adamant-2-ylmethyl isocyanate (1.9 equiv), DMF, rt, 12 h; (b) triethylamine (2 equiv), DMF, 0C25 C, 12h. The inhibitor potency of the synthesized compounds was measured using recombinant purified human being sEH and CMNPC (cyano(6-methoxynaphthalen-2-yl)methyl ((3-phenyloxiran-2-yl)methyl) carbonate) like a substrate as explained.25 For the di-adamantyl urea-based compounds (1aC1f), increasing the space of the flexible chain between the urea organizations from 2 to 6 carbons in the compounds 1aCc lead to a 400-fold increase in potency (lower IC50). Further increase of chain size to 8 carbons resulted in a 15-collapse decrease of inhibition potency for compound 1d, suggesting an optimal size for interaction with the enzyme. 1,4-Diaminobenzene (1e) and piperidine (1f) centered disubstituted diureas also showed poor potency, presumably because the significant reduction of flexibility between the urea groups did not permit an ideal positioning of the compounds inside the enzyme active site. In the 2 2, 3 and 4 series, not only the space and nature of the chain between the urea organizations (Z) but also the spacer linking the urea organizations with adamantane (X) were altered as well (Table 2). As found with the 1st series (Table 1), the presence of an alkyl chain in the middle of the molecule (series 2 and 3) yielded globally more potent inhibitors than the presence of a phenyl group (series 4). While, as observed for series 1, the space of the middle chain influenced potency (globally, series 2 (with 4 carbon) yielded more potent compounds than series 3 (8 carbon)), the IC50s were markedly influenced from the spacer between the adamantanes and ureas (X), especially in the 3 series. This provides evidence for the orientation of the inhibitor in the active site of human being sEH, and increases the possibility that the second CID 2011756 urea makes strong polar interactions with the enzyme. Interestingly, changing the relationship from your ureas to the adamantane from a 1- (2a and 3a) to a 2- (3a to 3d) position does not alter the potency of the compounds with short central alkyl chains (2a and 2d), but dramatically (500-collapse) decreases the potency of a compound with a longer central alkyl chain (3d). Table 1 IC50 ideals for diadamantyl urea-based sEH inhibitors 1aCf*. thead th colspan=”4″ valign=”bottom” align=”center” rowspan=”1″ Open in a separate windows hr / /th th valign=”bottom” align=”center” rowspan=”1″ colspan=”1″ Z /th th valign=”bottom” align=”center” rowspan=”1″ colspan=”1″ n /th th valign=”bottom” align=”center” rowspan=”1″ colspan=”1″ # /th CID 2011756 th valign=”bottom” align=”center” rowspan=”1″ colspan=”1″ IC50.