Many proteins have been proposed to act as surrogate markers of organ damage, yet for many candidates the essential characteristics which link the protein to the injured organ have not yet been described. We generated an NGAL-reporter mouse by inserting a di-fusion reporter gene, Luciferase2(Luc2)/mCherry(mC) into the Ngal locus. The Ngal-Luc2/mC reporter accurately recapitulated the endogenous message and illuminated injuries in vivo in real-time. In the kidney, Ngal-Luc2/mC imaging showed a sensitive, rapid, dose-dependent, reversible, and organ and cellular specific relationship with tubular stress, which quantitatively paralleled urinary Ngal (uNgal). Unexpectedly, specific cells of the distal nephron were the source of uNgal. Cells isolated from Ngal-Luc2/mC mice could also track both the onset and the resolution of the injury, and monitor the actions of NF-κB inhibitors and antibiotics in the case of infection. Accordingly, the imaging of Ngal-Luc2/mC mice and cells identified injurious and reparative agents which effect kidney damage.

Design, synthesis and biological evaluation of a series of 5-chloropyridine ester-derived severe acute respiratory syndrome-coronavirus chymotrypsin-like protease inhibitors is described. Position of the carboxylate functionality is critical to potency. Inhibitor 10 with a 5-chloropyridinyl ester at position 4 of the indole ring is the most potent inhibitor with a SARS 3Clpro IC 50 value of 30 nM and antiviral EC 50 value of 6.9 μM. Molecular Docking studies have provided possible binding modes of these inhibitors.© 2008 Elsevier Ltd. All rights reserved. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. 4 While SARS is contained in the world and no more cases have been reported since April 2004, there is expectation that this epidemic will strike again in an even more severe form. Furthermore, the nature of its unpredictable outbreak is a potential threat to the global economy and public heath. To date, no effective therapy exists for this viral illness. NIH Public AccessThe SARS coronavirus is a positive-strand RNA virus. The 5′ two-thirds of the genome encodes two overlapping polyproteins, pp1a and pp1ab, which are processed to generate the viral replication complex. During viral replication, the replicase polyprotein undergoes extensive processing by two viral proteases namely, chymotrypsin-like protease (3CLpro) and papainlike protease (PLpro). 5,6 Because of their essential roles in viral replication, both proteases are recognized as attractive targets for development of anti-SARS therapeutics. 7 The structure and activity of active sites of both SARS-CoV 3CLpro and SARS-CoV PLpro have been elucidated. Thus far, inhibitor design efforts are mostly limited to SARS-CoV 3CLpro and numerous covalent and noncovalent inhibitors have been reported. 7 In our continuing interest in the design and development of SARS-CoV 3CLpro inhibitors, we recently reported structurebased design of a number of potent peptidomimetic SARS-CoV 3CLpro inhibitors (1 and 2). The SARS-CoV 3CLpro active site contains a catalytic dyad where a cysteine residue acts as a nucleophile and a histidine residue acts as the general acid base. 9 The inhibitors bind to SARS-CoV-3CLpro through covalent bonding with the active site cysteine 145 residue. These inhibitors contain peptidomimetic scaffolds and lacked adequate potency, particularly antiviral activity suitable for drug-development. Recently, Wong and co-workers reported a new class of potent small molecule benzotriazole ester-based 3CLpro inhibitors. Compound 3 is the most potent inhibitor among the benzotriazole esters. 10 The mode of acti...

[structure: see text] An enantioselective total synthesis of (-)-lasonolide A is described. The upper tetrahydropyran ring was constructed stereoselectively by an intramolecular 1,3-dipolar cycloaddition reaction. The bicyclic isooxazoline led to the tetrahydropyran ring as well as the quaternary stereocenter present in the molecule. The lower tetrahydropyran ring was assembled by a catalytic asymmetric hetero-Diels-Alder reaction as the key step. Three stereocenters were enantioselectively installed in this single step reaction.

We report here a class of thiazolidine-2,4-diones and 2-thioxothiazolidin-4-ones as potent inhibitors of the lymphoid specific tyrosine phosphatase (Lyp) identified from high throughput screens. Chemical modification by incorporating the known phosphotyrosine (pTyr) mimics led to the discovery of a salicylate-based inhibitor with submicromolar potency.

The lymphoid tyrosine phosphatase (Lyp, PTPN22) is a critical negative regulator of T cell antigen receptor (TCR) signaling. A single-nucleotide polymorphism (SNP) in the ptpn22 gene correlates with the incidence of various autoimmune diseases, including type 1 diabetes, rheumatoid arthritis, and systemic lupus erythematosus. Since the disease-associated allele is a more potent inhibitor of TCR signaling, specific Lyp inhibitors may become valuable in treating autoimmunity. Using a structure-based approach, we synthesized a library of 34 compounds that inhibited Lyp with IC 50 values between 0.27 and 6.2 μM. A reporter assay was employed to screen for compounds that enhanced TCR signaling in cells, and several inhibitors displayed a dose-dependent, activating effect. Subsequent probing for Lyp's direct physiological targets by immunoblot analysis confirmed the ability of the compounds to inhibit Lyp in T cells. Selectivity profiling against closely related tyrosine phosphatases and in silico docking studies with the crystal structure of Lyp yielded valuable information for the design of Lyp-specific compounds.