Discovery of spirohydantoins as selective, orally bioavailable inhibitors of p300/CBP histone acetyltransferases.

p300 and CREB-binding protein (CBP) are essential for a multitude of cellular processes. Dysregulation of p300/CBP histone acetyltransferase activity is linked to a broad spectrum of human diseases including cancers. A novel drug-like spirohydantoin (21) has been discovered as a selective orally bioavailable inhibitor of p300/CBP histone acetyltransferase. Lead compound 21 is more potent than the first-in-class lead A-485 in both enzymatic and cellular assays and lacks the off-target inhibition of dopamine and serotonin transporters, that was observed with A-485.

Dose-independent genotoxic response in A549 cell line exposed to fungicide Iprodione.

The fungicide Iprodione is widely applied in vegetables and raises concern for human health. The A549 human lung carcinoma cell line is a suitable model for assessing the toxicological effects of drugs. The goal of this work was to evaluate the genotoxicity and oxidative stress in the A549 cell line exposed to sublethal concentrations from 3 to 100 µg/mL Iprodione considering LC50 = 243.4 µg/mL Iprodione, as determined by the MTT assay. Generalized Linear Mixed Models (GLMM) were performed to determine the association between the responses NDI, MNim and MNib and the explanatory variables. Iprodione and solvent were relativized to the control whereas the concentration was included as numeric variable. ANOVA was used for the comparison of treatments. The coefficients of linear association between the explanatory variables and NDI, and the coefficients of logistic association between explanatory variables and MNim were not significant. However, these coefficients showed significant association with MNib only for Iprodione treatment but not for Iprodione concentration, indicating lack of dose-response relationship. Genotoxicity risk assessment indicated that the increase in Iprodione concentrations increased slightly the probability of belonging to the genotoxic category. ANOVA showed significant differences in MNib, and non-significant differences in NDI and MNim among treatments. The oxidative stress analysis performed at 3, 12, and 25 µg/mL Iprodione showed a significant and linear increase in SOD, and a significant and linear decrease in GSH and GST. The Dunnett test was significant for GSH at 12 and SOD at 25 µg/mL.

Construction of EVA/chitosan based PEG-PCL micelles nanocomposite films with controlled release of iprodione and its application in pre-harvest treatment of grapes.

A novel nanocomposite poly(ethylene-co-vinyl acetate) (EVA) film with controlled in vitro release of iprodione (ID) was prepared. Chitosan (CS) was used as the reinforcement which enhances the water and oxygen permeability of films. ID loaded poly(ethylene glycol)-poly(ε-caprolactone) (PEG-PCL) (IPP) micelles were used as the drug carrier which endows the films with antifungal and controlled release ability. IPP micelles with spherical shape and uniform size were obtained, and the maximum encapsulation efficacy (EE) was 91.17 ± 5.03% by well controlling the feeding amount of ID. Incorporation CS could improve the oxygen and moisture permeability of films, and the maximum oxygen permeability (OP) and water vapor transmission rate (WVTR) were 477.84 ± 13.03 cc/(m2·d·0.1 MPa) and 8.60 ± 0.25 g m-2 d-1, respectively. After loading IPP micelles, the films showed an improved antifungal ability and temperature-sensitive drug release behavior, and were found to enhance the quality of grapes by pre-harvest spraying.

Development of a prodrug of hydantoin based TACE inhibitor.

Our research on hydantoin based TNF-α converting enzyme (TACE) inhibitors led to fused bi-heteroaryl hydantoin series that demonstrate sub-nanomolar potency (Ki) as well as excellent activity in human whole blood (hWBA). However, lead compound 2 posed some formulation challenges which prevented it for further development. A prodrug approach was investigated to address this issue. The pivalate prodrug 3 can be formulated as stable neutral form and demonstrated improved DMPK properties when compared with parent compound.

Inhibitors of protein arginine deiminases and their efficacy in animal models of multiple sclerosis.

Protein arginine deiminases (PAD) are implicated in a variety of inflammatory and neurodegenerative diseases including multiple sclerosis (MS). Following the discovery of an in silico hit containing hydantoin and a piperidine moiety, we hypothesized that a 2-carbon linker on the hydantoin would be necessary for a 5-membered heterocycle for optimal PAD inhibitory activity. We designed thirteen compounds as potential inhibitors of PAD2 and PAD4 enzymes-two important PAD enzymes implicated in MS. Two compounds, one with an imidazole moiety (22) and the other with a tetrazole moiety (24) showed good inhibition of PAD isozymes in vitro and in the EAE mouse model of MS in vivo. Further experiments suggested that compound 22, a non-covalent inhibitor of PAD2 and PAD4, exhibits dose-dependent efficacy in the EAE mouse model and in the cuprizone-mediated demyelination model.

Revisiting the SAR of the Antischistosomal Aryl Hydantoin (Ro 13-3978).

The aryl hydantoin 1 (Ro 13-3978) was identified in the early 1980s as a promising antischistosomal lead compound. However, this series of aryl hydantoins produced antiandrogenic side effects in the host, a not unexpected outcome given their close structural similarity to the antiandrogenic drug nilutamide. Building on the known SAR of this compound series, we now describe a number of analogs of 1 designed to maximize structural diversity guided by incorporation of substructures and functional groups known to diminish ligand-androgen receptor interactions. These analogs had calculated polar surface area (PSA), measured LogD7.4, aqueous kinetic solubility, and estimated plasma protein binding values in ranges predictive of good ADME profiles. The principal SAR insight was that the hydantoin core of 1 is required for high antischistosomal activity. We identified several compounds with high antischistosomal efficacy that were less antiandrogenic than 1. These data provide direction for the ongoing optimization of antischistosomal hydantoins.

Aryl hydantoin Ro 13-3978, a broad-spectrum antischistosomal.

OBJECTIVES: Praziquantel is the only drug available for the treatment of schistosomiasis and the state of the exhausted drug discovery pipeline is alarming. We restarted investigations on the abandoned antischistosomal Ro 13-3978, an aryl hydantoin discovered in the early 1980s by Hoffmann La-Roche. METHODS: Newly transformed schistosomula and adult Schistosoma mansoni were studied in the presence of Ro 13-3978 in vitro. The metabolic stability of Ro 13-3978 was determined in vitro using human and mouse liver S9 fractions. Dose-response relationship, stage specificity, hepatic shift and scanning electron microscopy studies were carried out in S. mansoni-infected mice. In addition, efficacy experiments were conducted in rodents infected with Echinostoma caproni and Fasciola hepatica as well as in S. mansoni-infected immunocompromised nude (Foxn1(nu)) mice. RESULTS: Ro 13-3978 showed minor in vitro activity and no damage to the tegument was found. No cytotoxicity was detected for Ro 13-3978. Ro 13-3978 was metabolically stable. ED50 values of 138.9 and 14.6 mg/kg were calculated for the treatment of juvenile and adult S. mansoni infections, respectively, with a single oral dose of Ro 13-3978. SEM studies revealed severe damage to the worms 48 h post-treatment of infected mice. A single oral dose of Ro 13-3978 (100 mg/kg) administered to S. mansoni-infected (Foxn1(nu)) mice reduced the worm burden by 88%. Ro 13-3978 was not active against E. caproni and F. hepatica in vivo. CONCLUSIONS: Ro 13-3978 has excellent antischistosomal properties in vivo. Structure-activity relationship studies with the aryl hydantoins have been launched in order to elucidate active pharmacophores, further investigate the mechanism of action and to identify a derivative with minimal antiandrogenic effects.

Creatinine metabolite, HMH (5-hydroxy-1-methylhydantoin; NZ-419), modulates bradykinin-induced changes in vascular smooth muscle cells.

A creatinine metabolite, 5-hydroxy-1-methylhydantoin (HMH: NZ-419), a hydroxyl radical scavenger, has previously been shown to confer renoprotection by inhibiting the progression of chronic kidney disease in rats. In the current study, we demonstrate that HMH modulates the effects of glucose and bradykinin (BK) in vascular smooth muscle cell (VSMC). HMH a novel anti-oxidant drug completely suppressed the expression of B2-kinin receptors (B2KR) in response to high glucose (25 mM) stimulation in VSMC and was also shown to attenuate the effects of BK on VSMC remodeling. HMH inhibited the BK-induced increase in MAPK phosphorylation and attenuated the increase in connective tissue growth factor (CTGF) protein levels in VSMC. These findings suggest that HMH may confer vascular protection against high glucose concentrations and BK-stimulation to ameliorate vascular injury and remodeling through its anti-oxidant properties.

ADME characterization in rats revealed immediate secretion of AZD7903 into the stomach after IV dosing.

The distribution of AZD7903 and/or its metabolites was studied in rats following a single p.o. or i.v. dose using quantitative whole-body autoradiography (QWBA). At 5 min after i.v. administration of the ¹4C compound, high levels of radioactivity were observed in the fundus of the stomach compared to blood and plasma and the rest of the stomach, indicating an active secretion of ¹4C material into the stomach. Also, excretion and pharmacokinetics were studied following p.o. and i.v. dosage in rats. The radioactivity was mainly excreted via feces, and even in i.v. administered bile-duct cannulated (BDC) animals a significant part of radioactivity (26% in males and 57% in females) was recovered in the feces in the form of parent compound and two minor metabolic products. The compound was well absorbed (F% 98 in males and 76 in females), and showed low clearance in plasma (0.14 L/h/kg in males and 0.03 L/h/kg in females) and low-intermediate Vd(ss) (0.7 L/kg). Clear differences in metabolic pathways (qualitative) and rates (quantitative) and consequently in PK parameters between sexes were observed. In summary, the results indicate AZD7903 being substrate for a transporter protein and support the hypothesis that the differences in disposition between sexes are due to differences in metabolic pathways and rates.

New biocide with both N-chloramine and quaternary ammonium moieties exerts enhanced bactericidal activity.

Considering the rise of antibiotic resistance, the development of new antibacterial agents with improved biocidal functions is urgently required. In this study, ionic 5,5-dimethylhydantoin (DMH) analogues containing either a quaternary ammonium moiety (2)-4) or a phosphonate functional group (5),-6), were designed and synthesized to investigate the possible enhancing effect of quaternary ammonium moieties on the antibacterial performance of N-chloramines. These ionic DMH analogues were converted to their N-chloramine counterparts either in free form or after being covalently immobilized on a polymer surface via the "click" chemistry method. In the subsequent antimicrobial assessment against multi-drug-resistant Escherichia coli (MDR-E. coli) and methicillin-resistant Staphylococcus aureus (MRSA), chlorinated 2 and 3, the cyclic N-chloramines with a structural cation, exhibited distinctly enhanced biocidal functions in solution and after immobilization on surfaces.

Formaldehyde-releasers in cosmetics: relationship to formaldehyde contact allergy. Part 2. Patch test relationship to formaldehyde contact allergy, experimental provocation tests, amount of formaldehyde released, and assessment of risk to consumers allergic to formaldehyde.

This is the second part of an article on formaldehyde-releasers in cosmetics. The patch test relationship between the releasers in cosmetics to formaldehyde contact allergy is reviewed and it is assessed whether products preserved with formaldehyde-releasers may contain enough free formaldehyde to pose a threat to individuals with contact allergy to formaldehyde. There is a clear relationship between positive patch test reactions to formaldehyde-releasers and formaldehyde contact allergy: 15% of all reactions to 2-bromo-2-nitropropane-1,3-diol and 40-60% of the reactions to the other releasers are caused by a reaction to the formaldehyde in the test material. There is only fragmented data on the amount of free formaldehyde in cosmetics preserved with formaldehyde donors. However, all releasers (with the exception of 2-bromo-2-nitropropane-1,3-diol, for which adequate data are lacking) can, in the right circumstances of concentration and product composition, release >200 p.p.m. formaldehyde, which may result in allergic contact dermatitis. Whether this is actually the case in any particular product cannot be determined from the ingredient labelling. Therefore, we recommend advising patients allergic to formaldehyde to avoid leave-on cosmetics preserved with quaternium-15, diazolidinyl urea, DMDM hydantoin, or imidazolidinyl urea, acknowledging that many would tolerate some products.

Synthesis and in vitro cytotoxic evaluation of novel diazaspiro bicyclo hydantoin derivatives in human leukemia cells: a SAR study.

To study the structure activity relationship (SAR) on the cytotoxic activity and probe the structural requirement for the potent antitumor activity, a series of novel diazaspiro bicyclo hydantoin derivatives were designed and synthesized. Their structures were confirmed by (1)H NMR, LCMS and IR analyses. The antiproliferative effect of these compounds were determined against human leukemia, K562 (chronic myelogenous leukemia) and CEM (T-cell leukemia) cells using trypan blue and MTT assay, and the SAR associated with the position of N-terminal substituents in diazaspiro bicyclo hydantoin have also been discussed. It has been observed that these compounds displayed strong, moderate and weak cytotoxic activities. Interestingly, compounds having electron withdrawing groups at third and fourth position of the phenyl ring displayed selectively cytotoxic activities to both the cell lines tested with IC(50) value lower than 50 muM. In addition, the cytotoxic activities of the compounds 7(a-o) bearing the substituents at N-3 position of diazaspiro bicyclo hydantoin increases in the order alkene > ester > ether and plays an important role in determining their antitumor activities. The position and number of substituents in benzyl group attached to N-8 of diazaspiro bicyclo hydantoin nucleus interacted selectively with specific targets leading to the difference of biochemical and pharmacological effects.

CRTH2 is not involved in the anti-enteropooling effect of PGD2 in the small intestine.

The majority of prostaglandins (PGs) are known to induce intestinal fluid secretion (enteropooling). In contrast, PGD(2) has been demonstrated to inhibit fluid secretion induced by other PGs. This study was aimed to investigate, by the use of selective agonists/antagonists, which type of PGD(2) receptor mediates this inhibitory effect. The DP1 agonist BW245C dose-dependently inhibited the enteropooling effect of 16,16-dimethyl-PGE(2). This inhibition was counteracted by the DP1 antagonist BWA868C. In contrast, the CRTH2 receptor does not seem to be involved in the anti-enteropooling effect of PGD(2), since the selective agonists 13,14-dihydro-15-keto-PGD(2) and 15(R)-15-methyl-PGD(2) were without effect. Therefore, our results suggest that the inhibitory effect of PGD(2) in the small intestine is mediated via activation of the DP1 receptor.

Interactive effect of histamine and prostaglandin D2 on nasal allergic symptoms in rats.

This study was undertaken to investigate the interactive effect of histamine and prostaglandin D(2) in nasal allergic symptoms in rats. The intranasal application of histamine at doses lower than 10 mumol/site caused no sneezing or nasal rubbing. In addition, prostaglandin D(2) also showed no significant increase in these responses, even at a dose of 10 nmol/site. On the other hand, the simultaneous instillation of histamine and prostaglandin D(2) resulted in a 1000 times more potent effect in inducing nasal symptoms than the administration of histamine alone. Thus, prostaglandin D(2) enhanced the actions of histamine in inducing sneezing and nasal rubbing in a dose-dependent manner, and significant effects were observed at doses higher than 1 nmol/site. The responses induced by the simultaneous application of histamine and prostaglandin D(2) were inhibited by chlorpheniramine, cyproheptadine, BW A868C and ramatroban. Chlorpheniramine and cyproheptadine showed the dose-related inhibition of nasal symptoms induced by the combined administration of histamine (10 nmol) and prostaglandin D(2) (10 nmol), but the effect of cyproheptadine was relatively weak compared with chlorpheniramine. Moreover, BW A868C and ramatroban also showed the inhibition of nasal symptoms induced by the simultaneous administration of histamine and prostaglandin D(2) in a dose-dependent manner. BW A868C was more potent in inhibiting the nasal symptoms than ramatroban. These results clearly indicate that prostaglandin D(2) showed a synergistic effect on sneezing and nasal rubbing induced by histamine in rats, and its effect occurred through both prostaglandin D(2) and CRTH2 (chemoattractant receptor-homologous molecule expressed on TH2 cells) receptors.

Discovery of potent, orally-active, and muscle-selective androgen receptor modulators based on an N-aryl-hydroxybicyclohydantoin scaffold.

A novel, N-aryl-bicyclohydantoin selective androgen receptor modulator scaffold was discovered through structure-guided modifications of androgen receptor antagonists. A prototype compound (7R,7aS)-10b from this series is a potent and highly tissue-selective agonist of the androgen receptor. After oral dosing in a rat atrophied levator ani muscle model, (7R,7aS)-10b demonstrated efficacy at restoring levator ani muscle mass to that of intact controls and exhibited >50-fold selectivity for muscle over prostate.

Synthesis and antimicrobial applications of 5,5'-ethylenebis[5-methyl-3-(3-triethoxysilylpropyl)hydantoin].

A novel, durable, long lasting, N-halamine siloxane monomer precursor, 5,5'-ethylenebis[5-methyl-3-(3-triethoxysilylpropyl)hydantoin] has been prepared and characterized by (1)H-NMR and FTIR for the purpose of functionalizing the surfaces of various materials. In this work, the precursor N-halamine moiety was attached by siloxane covalent bonding to surfaces of cotton fibers. Simulated laundering tests indicated that the chlorinated N-halamine structure could survive many repeated home launderings. The materials were rendered biocidal after exposure to oxidative halogen solutions, i.e. dilute household bleach. Once chlorinated, these materials were biocidal against Staphylococcus aureus and Escherichia coli. Upon loss of the halogen from either long-term use or consumption by the microbes on the surfaces, they could be simply recharged by further exposure to dilute bleach to regain biocidal activity.

Structure-activity relationship study of novel necroptosis inhibitors.

Necroptosis is a regulated caspase-independent cell death mechanism that results in morphological features resembling necrosis. It can be induced in a FADD-deficient variant of human Jurkat T cells treated with TNF-alpha. 5-(1H-Indol-3-ylmethyl)-2-thiohydantoins and 5-(1H-indol-3-ylmethyl)hydantoins were found to be potent necroptosis inhibitors (called necrostatins). A SAR study revealed that several positions of the indole were intolerant of substitution, while small substituents at the 7-position resulted in increased inhibitory activity. The hydantoin ring was also quite sensitive to structural modifications. A representative member of this compound class demonstrated moderate pharmacokinetic characteristics and readily entered the central nervous system upon intravenous administration.

Effects of BW245C, a prostaglandin dp receptor agonist, on systemic and regional haemodynamics in the anaesthetized rat.

1. Prostaglandin D (DP) receptor agonists have been shown to induce hypotension in rat models, possibly via peripheral vasodilation. However, it is not known which tissues and organs are most responsive. 2. In the present study, BW245C, a DP receptor-selective agonist, was administered to Inactin (Sigma, St Louis, MO, USA)-anaesthetized rats. Animals received three serial i.v. infusions (17 min each) of either BW245C (escalating doses of 0.3, 3 and 30 microg/kg; n=6) or vehicle (6% ethanol in normal saline; n=6). Mean arterial pressure (MAP) and heart rate were monitored continuously and regional blood flow was determined by the radionuclide-labelled microsphere method at baseline and at the end of each infusion. 3. It was found that BW245C dose-dependently reduced MAP; blood flow increased in forelimb skeletal muscle and skin, resulting in decreases in the regional vascular resistance (RVR) of skeletal muscle to -6+/-13, -53+/-11 and -68+/-6% of baseline following 0.3, 3 and 30 microg/kg BW245C, respectively (P<0.05 vs vehicle treatment for the two higher doses), and skin to -29+/-8, -55+/-8 (P<0.05) and -30+/-16% of baseline, respectively. Relative to vehicle, blood flow and RVR for brain, heart, lung, liver, stomach and kidney were not significantly affected by BW245C. 4. These results demonstrate that the hypotension resulting from DP receptor activation in the rat is mediated primarily through vasodilation of arterioles of skeletal muscle independent of changes in blood flow to vital organs.

Possible involvement of p38 in mechanisms underlying acceleration of proliferation by 15-deoxy-Delta(12,14)-prostaglandin J2 and the precursors in leukemia cell line THP-1.

15-deoxy-Delta(12,14)-prostaglandin J(2) (15dPGJ2), which is a ligand for peroxisome proliferator-activated receptor gamma (PPARgamma), induced apoptosis of several human tumors including gastric, lung, colon, prostate, and breast. However, the role of PPARgamma signals in other types of cancer cells (e.g., leukemia) except solid cancer cells is still unclear. The aim of this study is to evaluate the ability of 15dPGJ2 to modify the proliferation of the human leukemia cell line THP-1. 15dPGJ2 at 5 microM stimulated the proliferation in THP-1 at 24 to 72 h after incubation. In contrast, 15dPGJ2 at concentrations above 10 microM inhibited the proliferation through the induction of apoptosis. PGD2, PGJ2, and Delta12-PGJ2 (DeltaPGJ2), precursors of 15dPGJ2, had similar proliferative effects at lower concentrations, whereas they induced apoptosis at high concentrations. 15dPGJ2 and three precursors failed to induce the differentiation in THP-1 as assessed by using the differentiation marker CD11b. FACScan analysis revealed that PGD2 at 5 microM, PGJ2 at 1 microM, DeltaPGJ2 at 1 microM and 15dPGJ2 at 5 microM all accelerated cell cycle progression in THP-1. Immunoblotting analysis revealed that PGD2 at 5 microM and 15dPGJ2 at 5 microM inhibited the expression of phospho-p38, phospho-MKK3/MKK6, and phospho-ATF-2, and the expression of Cdk inhibitors including p18, p21, and p27 in THP-1. In contrast, PGJ2 at 1 microM and DeltaPGJ2 at 1 microM did not affect their expressions. These results suggest that 15dPGJ2 and PGD2 may, through inactivation of the p38 mitogen-activated protein kinase pathway, inhibit the expression of Cdk inhibitors, leading to acceleration of the THP-1 proliferation.