The enzyme 11β–hydroxysteroid dehydrogenase (HSD) type 1 converts inactive cortisone into active cortisol in cells, thereby raising the effective glucocorticoid (GC) tone above serum levels. We report that pharmacologic inhibition of 11β-HSD1 has a therapeutic effect in mouse models of metabolic syndrome. Administration of a selective, potent 11β-HSD1 inhibitor lowered body weight, insulin, fasting glucose, triglycerides, and cholesterol in diet-induced obese mice and lowered fasting glucose, insulin, glucagon, triglycerides, and free fatty acids, as well as improved glucose tolerance, in a mouse model of type 2 diabetes. Most importantly, inhibition of 11β-HSD1 slowed plaque progression in a murine model of atherosclerosis, the key clinical sequela of metabolic syndrome. Mice with a targeted deletion of apolipoprotein E exhibited 84% less accumulation of aortic total cholesterol, as well as lower serum cholesterol and triglycerides, when treated with an 11β-HSD1 inhibitor. These data provide the first evidence that pharmacologic inhibition of intracellular GC activation can effectively treat atherosclerosis, the key clinical consequence of metabolic syndrome, in addition to its salutary effect on multiple aspects of the metabolic syndrome itself.

We recently reported the discovery of AM-8553 (1), a potent and selective piperidinone inhibitor of the MDM2-p53 interaction. Continued research investigation of the N-alkyl substituent of this series, focused in particular on a previously underutilized interaction in a shallow cleft on the MDM2 surface, led to the discovery of a one-carbon tethered sulfone which gave rise to substantial improvements in biochemical and cellular potency. Further investigation produced AMG 232 (2), which is currently being evaluated in human clinical trials for the treatment of cancer. Compound 2 is an extremely potent MDM2 inhibitor (SPR KD = 0.045 nM, SJSA-1 EdU IC50 = 9.1 nM), with remarkable pharmacokinetic properties and in vivo antitumor activity in the SJSA-1 osteosarcoma xenograft model (ED50 = 9.1 mg/kg).

IMP-1 metallo-␤-lactamase (class B) is a plasmid-borne zinc metalloenzyme that efficiently hydrolyzes ␤-lactam antibiotics, including carbapenems, rendering them ineffective. Because IMP-1 has been found in several clinically important carbapenem-resistant pathogens, there is a need for inhibitors of this enzyme that could protect broad spectrum antibiotics such as imipenem from hydrolysis and thus extend their utility. We have identified a series of 2,3-(S,S)-disubstituted succinic acids that are potent inhibitors of IMP-1. Determination of high resolution crystal structures and molecular modeling of succinic acid inhibitor complexes with IMP-1 has allowed an understanding of the potency, stereochemistry, and structure-activity relationships of these inhibitors.Carbapenems such as imipenem (Scheme 1) have proven useful for the treatment of a variety of Gram-negative and Gram-positive infections (1, 2). Carbapenems and other ␤-lactam antibiotics covalently modify penicillin-binding proteins (PBPs) 1 involved in the peptidoglycan biosynthetic pathway of cell wall assembly in bacteria (3, 4). Resistance to carbapenems can arise because of acquisition of low affinity PBPs (3) (e.g. PBP2a of Staphylococcus aureus), altered membrane permeability (5), and expression of class A, B, and D ␤-lactamases (6 -10). Class B ␤-lactamases (metallo-␤-lactamases or MBLs) can hydrolyze a wide variety of substrates of the ␤-lactam class, including carbapenems, penicillins, and cephalosporins, rendering them ineffective as antibiotics.The IMP-1 gene encoding an MBL has been identified on a plasmid and in Japan has transferred among clinical isolates such as Pseudomonas aeruginosa (11,12), Klebsiella pneumoniae, Serratia marcescens, and other members of the Enterobacteriaceae (13,14). In addition, carbapenem-resistant clinical isolates expressing MBLs related to IMP-1 have been identified recently in Singapore (15), Italy (16), and Hong Kong (10). Such reports of plasmid-borne imipenem resistance highlight the need for inhibitors of IMP-1 that can restore the activity of carbapenems in resistant bacteria.Several classes of MBL inhibitors have been reported (for reviews, see Refs. 17 and 18)) including phenazines (19), trifluoromethyl alcohol and ketone derivatives of L-and D-alanine (20), thioesters (18, 21-23), thiols (24 -28), biphenyl tetrazoles (29, 30), and amino acid-derived hydroxamates (31). Biphenyl tetrazoles have been shown to reverse imipenem resistance in a clinical isolate of Bacteroides fragilis (29), and thioesters have been shown to reverse resistance to the carbapenem L-742,728 in a laboratory strain of Escherichia coli expressing IMP-1 (32). A 1␤-methylcarbapenem substituted at C-2 with a benzothienylthio moiety has been reported to be a potent IMP-1 inhibitor that can reverse resistance to imipenem in an IMP-1-producing strain of Serratia marcescens (33). Although the inhibitors described above have been reported to have good activity against a specific MBL, only certain thiols (e.g. SB 264218) exhibit broad spe...

Structure-based rational design led to the discovery of novel inhibitors of the MDM2-p53 protein-protein interaction. The affinity of these compounds for MDM2 was improved through conformational control of both the piperidinone ring and the appended N-alkyl substituent. Optimization afforded 29 (AM-8553), a potent and selective MDM2 inhibitor with excellent pharmacokinetic properties and in vivo efficacy.

BPT inhibitors can sensitize a resistant B. fragilis clinical isolate expressing metallo-beta-lactamase to the antibiotics imipenem or penicillin G but not to rifampicin.