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The design, synthesis, and the biological evaluation of 2-benzamido-pyrimidines as novel IKK inhibitors are described. By optimization of the lead compound 3, compounds 16 and 24 are identified as good inhibitors of IKK2 with IC(50) values of 40 and 25 nM, respectively. Compound 16 also demonstrated significant in vivo activity in an acute model of cytokine release.

Cinnamides as novel CCR1 antagonist chemotypes are described with high affinity to human and rodent receptors. A1B1 and A4B7 showed oral activity in the mouse collagen induced arthritis.

The surface and bulk components of the x-ray photoelectron spectra of free noble gas clusters are shown to display differences in the influence of postcollision interaction between the photoelectron and the Auger electron on the spectral line shape; the bulk component is observed to be less affected than the surface and atomic parts of the spectra. A model for postcollision interaction in nonmetallic solids and clusters is also provided which takes the polarization screening into account. Core-level photoelectron spectra of Ar, Kr, and Xe have been recorded to verify the dependence of the postcollision interaction effect on the polarizability of the sample.

A magnetic bottle spectrometer of the type recently developed by Eland et al. [Phys. Rev. Lett. 90, 053003 (2003).] has been implemented for use with synchrotron radiation, allowing multidimensional electron spectroscopy. Its application to the Xe 4d double Auger decay reveals all the energy pathways involved. The dominant path is a cascade process with a rapid (6 fs) ejection of a first Auger electron followed by the slower (>23 fs) emission of a second Auger electron. Weaker processes implying 3 electron processes are also revealed, namely, direct double Auger and associated Rydberg series.

(H2O)(N) clusters generated in a supersonic expansion source with N approximately 1000 were core ionized by synchrotron radiation, giving rise to core-level photoelectron and Auger electron spectra (AES), free from charging effects. The AES is interpreted as being intermediate between the molecular and solid water spectra showing broadened bands as well as a significant shoulder at high kinetic energy. Qualitative considerations as well as ab initio calculations explain this shoulder to be due to delocalized final states in which the two valence holes are mostly located at different water molecules. The ab initio calculations show that valence hole configurations with both valence holes at the core-ionized water molecule are admixed to these final states and give rise to their intensity in the AES. Density-functional investigations of model systems for the doubly ionized final states--the water dimer and a 20-molecule water cluster--were performed to analyze the localization of the two valence holes in the electronic ground states. Whereas these holes are preferentially located at the same water molecule in the dimer, they are delocalized in the cluster showing a preference of the holes for surface molecules. The calculated double-ionization potential of the cluster (22.1 eV) is in reasonable agreement with the low-energy limit of the delocalized hole shoulder in the AES.

Single photon double ionization of SF(6) has been investigated at the photon energies 38.71, 40.814, and 48.372 eV by using a recently developed time-of-flight photoelectron-photoelectron coincidence spectroscopy technique which gives complete two-dimensional e(-)-e(-) spectra. The first complete single photon double ionization electron spectrum of SF(6) up to a binding energy of approximately 48 eV is presented and accurately interpreted with the aid of Green's function ADC(2) calculations. Spectra which reflect either mainly direct or mainly indirect (via interatomic coulombic decay of F 2s holes) double ionization of SF(6) are extracted from the coincidence map and discussed. A previous, very low value for the onset of double ionization of SF(6) is found to energetically coincide with a peak structure related to secondary inelastic scattering events.

A recently developed time-of-flight photoelectron-photoelectron coincidence spectroscopy technique, which gives complete two-dimensional e(-)-e(-) spectra in single photon double ionization, is applied to molecular oxygen at photon energies below and above the adiabatic double ionization threshold of O(2). Analysis of the two-dimensional coincidence maps reveals specific indirect pathways for the double ionization process. Dissociative ionization paths with subsequent autoionization of atomic oxygen are found to be the dominant processes for all chosen photon energies. Spectra of the photoelectrons coincident with the autoionization electrons show that intermediate O(2)(+) states are involved which do not autoionize to molecular O(2)(2+). In particular, the ground state of O(2)(2+) is vibrationally resolved and shows a regular progression which can be well described by direct Franck-Condon transitions at an internuclear distance R(e)(X (1)Sigma(g)(+))=1.054 A. Quantum yields of double ionization for O(2), of a form discussed in this paper, are determined.

A quantitative determination of 2s vacancy lifetimes in surface and bulk atoms of free Ne clusters has been made. While for free atoms the 2s inner-valence hole has a ps lifetime, it reduces to 6+/-1 fs for cluster bulk atoms. For surface atoms, the lifetime is on average longer than 30 fs. The lifetime estimate was obtained from fits of high-resolution photoelectron spectra of Ne clusters. The shortening of the lifetime is attributed to the coordination dependent interatomic Coulombic decay, which is extremely sensitive to internuclear distances.

A library of trisubstituted oxazoles, thiazoles, imidazoles (1,2,4- and 2,4,5-substituted) and imidazo[1,2-b]pyridines was prepared and evaluated in vitro as p38alpha inhibitors and in vivo in several models of rheumatoid arthritis. Four structures--32, 37, 45 and 59--were identified as potent inhibitors of p38alpha with high efficacy in the LPS induced TNFalpha release model in the mouse, the adjuvant induced arthritis and the collagen induced arthritis in the rat with ED50s between 1.0 and 9.5 mg/kg p.o.

Benzoylpyridines and benzophenones were synthesized and evaluated in vitro as p38alpha inhibitors and in vivo in several models of rheumatoid arthritis. Oral activity was found to depend upon substitution: 1,1-dimethylpropynylamine substituted benzophenone 10b (IC50: 14 nM) and pyridinoyl substituted benzimidazole 17b (IC50: 21 nM) showed highest efficacy and selectivity with ED50s of 9.5 and 8.6 mg/kg p.o. in CIA.

A new approach for obtaining an estimate of the effective size of the free neutral clusters is proposed. The approach relies on an experimental measure of the surface and interior or "bulk" cluster atoms provided by the x-ray photoelectron spectroscopy and on a model for the attenuation of photoelectrons ejected from the bulk of the cluster as the result of the ionizing irradiation. The experimental part gives the ratio of the electron signal from the bulk cluster atoms to that from the cluster surface atoms for a wide range of cluster sizes and electron kinetic energies. The attenuated response of the bulk atoms is modeled using an exponential law with the cluster size and kinetic-energy-dependent electron escape depth as parameters. For the experimental size range, model-based calculations for Ar, Kr, and Xe clusters are presented. The cluster size estimates obtained from comparison of the model calculations and experimental results agree well with those determined from the parameters of the cluster creation process. The combination of experiment and modeling also makes it possible to estimate the effective escape depth for electron propagation in free clusters. For Ar, Kr, and Xe clusters of varying mean size, absolute determination of the surface and bulk electron binding energies of the core levels used in the experiments has also been made., ((c) 2004 American Institute of Physics)

Fragmentation of the SF6 molecule upon F 1s excitation has been studied by resonant photoemission. The F atomiclike Auger line exhibits the characteristic Doppler profile that depends on the direction of the photoelectron momentum relative to the polarization vector of the radiation as well as on the photon energy. The measured Doppler profiles are analyzed by the model simulation that takes account of the anisotropy of the Auger emission in the molecular frame. The Auger anisotropy extracted from the data decreases with an increase in the F-SF5 internuclear distance.

The resonant Auger spectrum from the decay of F 1s-excited CF4 is measured. Several lines exhibit a nondispersive kinetic energy as the exciting photon energy is tuned through the resonance region. The F 1s(-1) atomiclike Auger line is split into two components due to the emission of Auger electrons by a fragment in motion, when electron emission is observed along the polarization vector of the light. This Doppler splitting is direct evidence that the core excitation leads to T(d)-->C(3v) symmetry lowering, by elongation of a specific C-F bond preferentially aligned along the polarization vector of the incident photon.

An interference quenching of the nu(")=1 vibrational line in the resonant Auger decay of N 1s-->pi(*) core-excited N2 is observed and analyzed. The intensity ratio between the nu(")=1 and nu(")=0 vibrational levels of the X2Sigma(+)(g) final state shows a surprising nonmonotonous variation as a function of frequency detuning, going through a minimum with a complete suppression of nu(")=1. We have developed a simple model which shows a linear relation between the value of the detuning frequency for this minimum and the equilibrium bond distance R(0)(c) of the core-excited state. A new way is thus established of determining the equilibrium bond distance for the core-excited state with a precision deltaR(0)(c)<10(-3) A.

2,6-Diamino-3,5-difluoropyridinyl substituted pyridinylimidazoles, -pyrroles, -oxazoles, -thiazoles and -triazoles have been identified as novel p38alpha inhibitors. Pyridinylimidazole 11 potently inhibited LPS-induced TNFalpha in mice, showed good efficacy in the established rat adjuvant (ED(50): 10 mg/kg po b.i.d.) and collagen induced arthritis (ED(50): 5 mg/kg po b.i.d.) with disease modifying properties based on histological analysis of the joints.

Novel hydroxamate inhibitors of tumor necrosis factor converting enzyme (TACE) and matrix metalloproteases (MMPs) have been synthesized via the Claisen-Ireland rearrangement. Aryl residues have been introduced to fill the enzyme's P1' specificity pocket. The best compound inhibits MMPs and TACE with nanomolar potency and inhibits the release of TNFalpha from cells with an IC50 of 48 nM. Oral administration to rats inhibits the LPS-induced plasma TNFalpha levels with an ED50 of 1 mg/kg.

The femtosecond dissociation of HCl after core excitation has been studied through the resonant Auger decay. The spectra contain contributions from decay occurring at both "molecular" and "atomic" internuclear distances. We have observed a new interference mechanism in these spectra: An atomic spectral line develops into a negative spectral contribution, a "hole," when detuning the excitation energy from the maximum of the Cl2p(-1)sigma(*) resonance. Resonant x-ray scattering theory quantitatively explains this behavior as due to a novel destructive continuum-continuum interference between molecular and atomic contributions to the Auger decay.

The 4-hydroxypiperidine substituent was found to confer high p38 selectivity devoid of COX-1 affinity, when attached to a series of pyridinyl substituted heterocycles. Pyridinyloxazole 11 showed a promising in vivo profile with bioavailability of 64% and ED50 in rat collagen induced arthritis of 10 mg/kg po bid. In contrast to pyridinylimidazoles such as SB 203580, 11 did not inhibit human cytochrome P450 isoenzymes.

By exploiting the core-excitation-induced dissociation of O2, we find that the Auger emission exhibits a Doppler-like energy shift. We show this to be a manifestation of localization of the core hole and propose that the problem of core-hole localization versus delocalization in core-hole spectroscopies may be resolved by considering the nature of the measurement.

The two apoptosis receptors of mammalian cells, i.e. the 55 kDa TNF receptor (TNF-R1) and CD95 (Fas/APO1) are activated independently of each other, however, their signaling involves a variety of ICE-related proteases [I]. We used a cell-permeable inhibitor of ICE-like protease activity to examine in vivo whether post-receptor signaling of TNF and CD95 are fully independent processes. Mice pretreated with the inhibitor, Z-VAD-fluoromethylketone (FMK) were dose-dependently protected from liver injury caused by CD95 activation as determined by plasma alanine aminotransferase and also from hepatocyte apoptosis assessed by DNA fragmentation (ID50 = 0.1 mg/kg). A dose of 10 mg/kg protected mice also from liver injury induced by TNF-alpha. Similar results were found when apoptosis was initiated via TNF-alpha or via CD95 in primary murine hepatocytes (IC50 = 1.5 nM) or in various human cell lines. In addition to prevention, an arrest of cell death by Z-VAD-FMK was demonstrated in vivo and in vitro after stimulation of apoptosis receptors. These findings show in vitro and in vivo in mammals that CD95 and the TNF-alpha receptor share a distal proteolytic apoptosis signal.

1. We have compared the binding properties of several hexocyclium and sila-hexocyclium derivatives to muscarinic M1 receptors (in rat brain, human neuroblastoma (NB-OK 1) cells and calf superior cervical ganglia), rat heart M2 receptors, rat pancreas M3 receptors and M4 receptors in rat striatum, with their functional antimuscarinic properties in rabbit vas deferens (M1/M4-like), guinea-pig atria (M2), and guinea-pig ileum (M3) muscarinic receptors. 2. Sila-substitution (C/Si exchange) of hexocyclium (-->sila-hexocyclium) and demethyl-hexocyclium (-->demethyl-sila-hexocyclium) did not significantly affect their affinities for muscarinic receptors. By contrast, sila-substitution of o-methoxy-hexocyclium increased its affinity 2 to 3 fold for all the muscarinic receptor subtypes studied. 3. The p-fluoro- and p-chloro-derivatives of sila-hexocyclium had lower affinities than the parent compound at the four receptor subtypes, in binding and pharmacological studies. 4. In binding studies, o-methoxy-sila-hexocyclium (M1 = M4 > or = M3 > or = M2) had a much lower affinity than sila-hexocyclium for the four receptor subtypes, and discriminated the receptor subtypes more poorly than sila-hexocyclium (M1 = M3 > M4 > M2). This is in marked contrast with the very clear selectivity of o-methoxy-sila-hexocyclium for the prejunctional M1/M4-like heteroreceptors in rabbit vas deferens. 5. The tertiary amines demethyl-hexocyclium, demethyl-sila-hexocyclium and demethyl-o-methoxy-sila-hexocyclium had 10 to 30 fold lower affinities than the corresponding quaternary ammonium derivatives.

Muscarinic receptors of resistance vessels (submucosal arterioles, outside diameter 50-75 microns) from the guinea-pig small intestine were investigated in vitro using a computer-assisted videomicroscopy system (Diamtrak). The muscarinic receptor which mediates vasodilation of precontracted [U-46619 (300 nM) or (-)-noradrenaline (10 microM)] arterioles was characterized with several muscarinic agonists and subtype-selective antagonists. The following agonists all produced equivalent maximum vasodilation (given in rank order of potency): acetylcholine = arecaidine propargyl ester (APE) greater than oxotremorine = (+/-)-muscarine = (+/-)-methacholine greater than carbachol greater than 4-[[N-(4-chlorophenyl)carbamoyl]oxy]-2-butynyltrimethylammonium iodide (4-Cl-McN-A-343). 4-[[N-(3-Chlorophenyl)-carbamoyl]oxy]-2-butynyltrimethylammonium chloride (McN-A-343) and N-ethyl-guvacine propargyl ester (NEN-APE) produced minimal or no arteriolar vasodilation. The muscarinic antagonists pirenzepine, (+-)-5,11-dihydro-11-[[[2-[2-((dipropylamino)methyl)-1-piperidinyl] ethyl]amino]-carbonyl]-6H-pyrido(2,3-b)(1,4)-benzodiazepin-6-one (AF-DX 384), 11-[[4-[4-(diethylamino)butyl]-1-piperidinyl]acetyl]-5,11-dihydro- 6H-pyrido(2,3-b)(1,4)-benzodiazepin-6-one (AQ-RA 741), p-fluorohexahydro-sila-difenidol (p-F-HHSiD), 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) and (R)- and (S)-hexahydro-difenidol [(R)-HHD, (S)-HHD] shifted the muscarine, methacholine or carbachol dose-response curve to the right in a competitive manner. Schild analysis of the data yielded pA2 values for pirenzepine (6.74/6.9), AF-DX 384 (6.72), AQ-RA 741 (6.58), p-F-HHSiD (7.53/7.57), 4-DAMP (9.06), (R)-HHD (7.88/8.32) and (S)-HHD (5.52/5.88). Thus, it can be concluded that submucosal arterioles possess only the M3 functional muscarinic receptor, the activation of which causes blood vessel dilation.(ABSTRACT TRUNCATED AT 250 WORDS)

A method was developed to determine the affinities of antimuscarinic drugs at M1 receptors. [3H](+/-)-Telenzepine served as radioligand in crude preparations of calf superior cervical ganglia and showed high affinity for a single receptor population, consisting of M1 receptors (KD = 1.12 nM). Kinetic experiments showed monophasic association (k1 = 0.017 min-1 nM-1) and dissociation (k-1 = 0.017 min-1) kinetics, the half-life of dissociation being 41 min at 37 degrees C. The kinetic KD value amounted to 1.00 nM. M1 affinities for pirenzepine, methoctramine, hexahydro-sila-difenidol and p-fluoro-hexahydro-sila-difenidol determined in competition experiments were similar to those found in functional studies with M1 receptors in rabbit isolated vas deferens. The binding assay was used to determine the affinities of the (R) and (S) enantiomers of tertiary (trihexyphenidyl, hexahydro-difenidol, hexbutinol, p-fluoro-hexbutinol) and quaternary muscarinic antagonists (trihexyphenidyl methiodide, hexbutinol methiodide). Comparison of results obtained with the rabbit vas deferens suggested that the ionic environment may influence the affinities.

1. The affinities of the (R)- and (S)-enantiomers of hexahydro-difenidol (1) and its acetylenic analogues hexbutinol (2), hexbutinol methiodide (3) and p-fluoro-hexbutinol (4) (stereochemical purity greater than 99.8%) for muscarinic receptors in rabbit vas deferens (M1), guinea-pig atria (M2) and guinea-pig ileum (M3) were measured by dose-ratio experiments. 2. The (R)-enantiomers consistently showed higher affinities than the (S)-isomers. The stereoselectivity ratios [(R)/(S)] were greatest with the enantiomers of 1 (vas deferens: 550; ileum: 191; atria: 17) and least with those of the p-Fluoro-analogue 4 (vas deferens: 34; ileum: 8.5; atria: 1.7). 3. The enantiomeric potency ratios for compounds 1-4 were highest in rabbit vas deferens, intermediate in guinea-pig ileum and much less in guinea-pig atria. Thus, these ratios may serve as a predictor of muscarinic receptor subtype identity. 4. (S)-p-Fluoro-hexbutinol [(S)-4] showed a novel receptor selectivity profile with preference for M3 receptors: M3 greater than M2 greater than or equal to M1. 5. These results do not conform to Pfeiffer's rule that activity differences between enantiomers are greater with more potent compounds.

In an attempt to assess the structural requirements of hexahydro-sila-difenidol for potency and selectivity, a series of analogues modified in the amino group and the phenyl ring were investigated for their affinity to muscarinic M1-(rabbit vas deferens), M2- (guinea-pig atria) and M3- (guinea-pig ileum) receptors. All compounds were competitive antagonists in the three tissues. Their affinities to the three muscarinic receptor subtypes differed by more than two orders of magnitude and the observed receptor selectivities were not associated with high affinity. The pyrrolidino and hexamethyleneimino analogues, compounds substituted in the phenyl ring with a methoxy group or a chlorine atom as well as p-fluoro-hexahydro-difenidol displayed the same affinity profile as the parent compound, hexahydro-sila-difenidol: M1 approximately M3 greater than M2. A different selectivity pattern was observed for p-fluoro-hexahydro-sila-difenidol: M3 greater than M1 greater than M2. This compound exhibited its highest affinity for M3-receptors in guinea-pig ileum (pA2 = 7.84), intermediate affinity for M1-receptors in rabbit vas deferens (pA2 = 6.68) and lowest affinity for the M2-receptors in guinea-pig atria (pA2 = 6.01). This receptor selectivity profile of p-fluoro-hexahydro-sila-difenidol was confirmed in ganglia (M1), atria (M2) and ileum (M3) of the rat. Furthermore, dose ratios obtained with either pirenzepine (M1) or hexahydrosila-difenidol (M2 and M3) and the p-fluoro analogue used in combination suggested that the antagonism was additive, implying mutual competition with a single population of muscarinic receptor subtypes. These results indicate that p-fluoro-hexahydro-sila-difenidol represents a valuable tool for characterization of muscarinic receptor subtypes.

A series of hexahydro-difenidol (HHD) and hexahydro-sila-difenidol (HHSiD) analogues modified in the amino group, the phenyl ring and in the alkylene chain were investigated for their binding and functional properties at muscarinic M1, M2 and M3 receptors. Novel muscarinic receptor antagonists were obtained which exhibited different receptor selectivity profiles from the parent compounds HHD and HHSiD (M1 congruent to M3 greater than M2), e.g. HHD and HHSiD methiodides, M1 greater than M2 congruent to M3; p-fluoro-HHSiD, M3 greater than M1 greater than M2; trans-hexbutenol, M1 greater than M3 greater than M2; and (s)-p-fluoro-hexbutinol, M3 greater than M2 congruent to M1. Stereoselectivity ratios [(R)/(S)] for the enantiomers of HHD, hexbutinol and p-fluoro-hexbutinol were highest at M1, intermediate at M3 and lowest at M2 receptors.

High stereoselectivity was observed for the enantiomers of trihexyphenidyl and trihexyphenidyl methiodide at muscarinic M1-receptors in field-stimulated rabbit vas deferens and at M2 alpha- and M2 beta-receptors in guinea-pig atrium and ileum, respectively. Considerably higher affinities (up to 1700-fold) were found for the (R)-(-)-enantiomers. The stereochemical demands made by the muscarinic receptor subtypes were most stringent at the M1-receptors. The (R)-(-)-enantiomers were found to be potent M1-selective antagonists (pA2 = 10.1/10.6). They showed a 91- and 45-fold selectivity for M1- over M2 alpha-receptors, respectively.

The stereoselectivity of the interaction with muscarinic receptors of enantiomers of a series of chiral antagonists is receptor subtype dependent. There is no overall relationship between stereoselectivity and receptor affinity. Depending on the antagonist studied, receptor stereoselectivity may indeed reflect: (1) the weakening or loss of a single interaction involving one of the four groups bound to the asymmetric carbon; (2) steric hindrance preventing optimum interaction of the low affinity steroisomer with the receptor; and/or (3) the inversion of the relative positions of two moieties of the ligand with similar structural and electronic properties i.e. comparable affinities for the two corresponding subsites in the receptor.

The affinity of the enantiomers of phenglutarimide at three muscarinic receptor subtypes was examined in vitro using field-stimulated rabbit vas deferens (M1 receptors) and guinea pig atria (M2 alpha receptors) and ileum (M2 beta receptors). Extremely high stereoselectivity was observed and higher affinities (up to 6000-fold) were found for the (+)-S-enantiomer. The stereoselectivity ratios were different at the three subtypes, and the stereochemical demands made by the muscarinic receptors were most stringent at M1 receptors. (+)-(S)-Phenglutarimide was found to be a potent M1-selective antagonist (pA2 at M1 = 8.53). Its receptor selectivity profile is qualitatively similar to that of pirenzepine. (-)-(R)-Phenglutarimide showed no comparable discriminatory properties.