1,4-Benzodiazepines as inhibitors of respiratory syncytial virus

Respiratory syncytial virus (RSV) is the cause of one-fifth of all lower respiratory tract infections worldwide and is increasingly being recognized as a serious threat to patient groups with poorly functioning immune systems. Our approach to finding a novel inhibitor of this virus was to screen a 20 000-member diverse library in a whole cell XTT assay. Parallel assays were carried out in the absence of virus in order to quantify any associated cell toxicity. This identified 100 compounds with IC50's less than 50 μM. A-33903 (18), a 1,4-benzodiazepine analogue, was chosen as the starting point for lead optimization. This molecule was moderately active and demonstrated good pharmacokinetic properties. The most potent compounds identified from this work were A-58568 (47), A-58569 (44), and A-62066 (46), where modifications to the aromatic substitution enhanced potency, and A-58175 (42), where the amide linker was modified

Observation of diffractive J/psi production at the Fermilab Tevatron

We report the first observation of diffractive J/psi(→ mu (+)mu (-)) production in [(p)power bar] collisions at roots = 1.8 TeV. Diffractive events are identified by their rapidity gap signature. In a sample of events with two muons of transverse momentum p(T)(mu) gt 2 GeV/c within the pseudorapidity region \ eta \ lt 1.0, the ratio of diffractive to total J/[psi] production rates is found to be R-J/psi = [1.45 +/- 0.25]%. ne ratio R-J/psi(X) is presented as a function of x-Bjorken. By combining it with our previously measured corresponding ratio R-jj(x) for diffractive dijet production, we extract a value of 0.59 +/- 0.15 for the gluon fraction of the diffractive structure function of the proton

Searches for new physics in events with a photon and b-quark jet at CDF

We have searched for evidence of physics beyond the standard model in events that include an energetic photon and an energetic b-quark jet, produced in 85 pb(-1) of (p) over barp collisions at 1.8 TeV at the Tevatron Collider at Fermilab. This signature, containing at least one gauge boson and a third-generation quark, could arise in the production and decay of a pair of new particles, such as those predicted by supersymmetry, leading to a production rate exceeding standard model predictions. We also search these events for anomalous production of missing transverse energy, additional jets and leptons (e, mu and tau), and additional b quarks. We find no evidence for any anomalous production of gammab or gammab + X events, We present limits on two supersymmetric models: a model where the photon is produced in the decay (χ) over tilde (0)(2)→gamma(χ) over tilde (0)(1), and a model where the photon is produced in the neutralino decay into the gravitino LSP, (χ) over tilde (0)(1)→gamma(G) over tilde. We also present our limits in a model-independent form and test methods of applying model-independent limits