Orally active MMP-1 sparing α-tetrahydropyranyl and α-piperidinyl sulfone matrix metalloproteinase (MMP) inhibitors with efficacy in cancer, arthritis, and cardiovascular disease

α-Sulfone-α-piperidine and α-tetrahydropyranyl hydroxamates were explored that are potent inhibitors of MMP's-2, -9, and -13 that spare MMP-1, with oral efficacy in inhibiting tumor growth in mice and left-ventricular hypertrophy in rats and in the bovine cartilage degradation ex vivo explant system. α-Piperidine 19v (SC-78080/SD-2590) was selected for development toward the initial indication of cancer, while α-piperidine and α-tetrahydropyranyl hydroxamates 19w (SC-77964) and 9i (SC-77774), respectively, were identified as backup compounds.

Pyrrolizidine Esters and Amides as 5-HT4 Receptor Agonists and Antagonists

A series of pyrrolizidine esters, amides, and ureas was prepared and tested for 5-HT(4) and 5-HT(3) receptor binding, 5-HT(4) receptor agonism in the rat tunica muscularis mucosae (TMM) assay, and for 5-HT(3) receptor-mediated functional antagonism in the Bezold-Jarisch reflex assay. Several pyrrolizidine derivatives were identified with high affinity for the 5-HT(4) receptor, including benzamide 12a (SC-53116), a potent and selective 5-HT(4) partial agonist that exhibits efficacy in promoting antral contractions and activity in promoting gastric emptying in canine models. Also discovered were 5-HT(4) receptor antagonists, including imidazopyridine amide 12h (SC-53606), which is a potent and selective 5-HT(4) receptor antagonist with a pA(2) value of 8.13 in the rat TMM assay. N-Methyl indole ester 13d was identified as a potent 5-HT(4) antagonist with a pA(2) value of 8.93. High selectivity was observed for these pyrrolizidine derivatives versus other monoamine receptors, including 5-HT(1), 5-HT(2), D(1), D(2), alpha(1), alpha(2), and beta receptors.

Synthesis and Structure−Activity Relationships of β- and α-Piperidine Sulfone Hydroxamic Acid Matrix Metalloproteinase Inhibitors with Oral Antitumor Efficacy

alpha-Piperidine-beta-sulfone hydroxamate derivatives were explored that are potent for matrix metalloproteinases (MMP)-2, -9, and -13 and are sparing of MMP-1. The investigation of the beta-sulfones subsequently led to the discovery of hitherto unknown alpha-sulfone hydroxamates that are superior to the corresponding beta-sulfones in potency for target MMPs, selectivity vs MMP-1, and exposure when dosed orally. alpha-Piperidine-alpha-sulfone hydroxamate 35f (SC-276) was advanced through antitumor and antiangiogenesis assays and was selected for development. Compound 35f demonstrates excellent antitumor activity vs MX-1 breast tumor in mice when dosed orally as monotherapy or in combination with paclitaxel.

Synthesis of Diazepinones via Intramolecular Transamidation

[structure: see text] The synthesis of a collection of bicyclic fused azepinones via an intramolecular beta-lactam ring-opening strategy is reported. Depending on the chirality of the various inputs, complete stereocontrol of product formation is achieved.

Bridgehead-methyl analog of SC-53116 as a 5-HT4 agonist

Pyrrolizidine benzamide (+/-)-2, the bridgehead-methyl analog of SC-53116, was prepared and evaluated for 5-HT(4) agonism activity in the rat tunica muscularis (TMM) mucosae assay. Compound (+/-)-2 has an EC(50) of 449 nM in the TMM assay, as compared to 23 nM for SC-53116, and 66 nM for the racemate of SC-53116.

alpha-Amino-beta-sulphone hydroxamates as potent MMP-13 inhibitors that spare MMP-1

A series of alpha-amino-beta-sulphone hydroxamates was prepared and evaluated for potency versus MMP-13 and selectivity versus MMP-1. Various substituents were employed on the alpha-amino group (P(1) position), as well as different groups attached to the sulphone group extending into P(1)'. Low nanomolar potency was obtained for MMP-13 with selectivity versus MMP-1 of >1000x for a number of analogues.

Selective, orally active MMP inhibitors with an aryl backbone

This letter describes SAR exploration and rat PK optimization of a series of novel, MMP-1 sparing aryl hydroxamate sulfonamides with activity against MMP-2 and MMP-13.

Synthesis and activity of selective MMP inhibitors with an aryl backbone

A series of novel, MMP-1 sparing arylhydroxamate sulfonamides with activity against MMP-2 and -13 is described.

The herpesvirus protease: mechanistic studies and discovery of inhibitors of the human cytomegalovirus protease

The herpesvirus protease is a recently identified enzyme which is essential for viral replication. It is found in all herpesviruses and offers a new molecular target for therapeutic intervention. Its genomic structure has recently been described and consists of a large open reading frame which encodes a fusion protein containing an amino-terminal protease domain in-frame with a carboxyl-terminal "assembly protein-like" domain. Auto-processing releases the amino-terminal protease as a maturational enzyme. The herpesvirus protease has been characterized as a novel serine protease. Four surface accessible sulfhydryl groups have been identified in the human cytomegalovirus (HCMV) protease. Utilizing a fluorogenic DABCYL-EDANS substrate assay, directed screening has identified a class of sulfhydryl-modifying benzimidazolylmethyl sulfoxides which inhibits recombinant HCMV protease. Site-directed mutagenesis studies suggest oxidative modification of surface-accessible HCMV protease Cys138 (and possibly Cys161) by this class of inhibitors. The benzimidazolylmethyl sulfoxide 1 inhibits HCMV protease (IC50 = 1.9 microM), exhibits selectivity vs. mammalian serine proteases, and exhibits antiviral activity in an HCMV infected cell culture assay.

(Acyloxy)benzophenones and (acyloxy)-4-pyrones. A new class of inhibitors of human neutrophil elastase

A series of 4-(acyloxy)- and 4,4'-bis(acyloxy)benzophenones were synthesized. Some of them, pivalates (trimethylacetates) and isobutyrates in particular, were found to be potent and selective inhibitors of human neutrophil (leukocyte) elastase. A series of 2-[(acyloxy)methyl]-5-(acyloxy)-4-pyrones were synthesized regioselectively from kojic acid. The 4-pyrones bearing a long chain acyl group at the 2-position and either pivaloyloxy or isobutyryloxy at the 5-position were potent and selective inhibitors of the human elastase. A number of analogues and derivatives in both series were synthesized in order to study the structure-activity relationship as summarized in Tables I-VI and in Tables IX and X. The inhibition was selective to human neutrophil elastase. No inhibition of porcine pancreatic elastase or bovine pancreatic chymotrypsin (Tables VII and XI) was observed. The most likely mechanism of inhibition is discussed. The implication of these findings for the treatment of rheumatoid arthritis and emphysema is outlined.