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Kristian K Jensen,
Neil S Geoghagen,
Lan Jin,
Tom G Holt,
Qi Luo, Lorraine Malkowitz,
Weihua Ni,
Shuo Quan,
M Gerard Waters,
Aiwu Zhang,
Heather H Zhou,
Kang Cheng,
Ming-Juan Luo
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ABSTRACT: Hydrogen sulfide (H(2)S) is a recently discovered gasotransmitter found in mammalian tissues and blood. Treatment with H(2)S donor molecules has shown promising results in preclinical models of inflammatory and cardiovascular diseases. Augmentation of H(2)S levels thus holds promise as a novel therapeutic approach for treatment of disease in man. Cystathionine β-synthase (CBS) has been shown to catalyze H(2)S production in vitro. CBS enzyme activity is allosterically regulated by the endogenous activator S-adenosyl methionine. This mode of regulation suggests the possibility for designing a small molecule activator of CBS to enhance H(2)S production. This hypothesis, however, has not been directly tested in vivo. We show here that CBS contributes significantly to endogenous H(2)S production in mice: adenovirus mediated over expression of CBS in the liver significantly increased circulating levels of H(2)S, whereas CBS deficiency resulted in reduced levels. We demonstrate that CBS enzyme from endogenous sources can be activated by S-adenosyl methionine to a greater extent compared to recombinant enzyme, suggesting greater potential for activation than previously anticipated. Importantly, we show that circulating H(2)S levels are increased by pharmacological activation of CBS in vivo; i.e. in the presence of the endogenous activator. Together, our data demonstrate that CBS activity partially regulates endogenous H(2)S in mice, and suggest that pharmacological activation of CBS is a promising approach for enhancing endogenous production of H(2)S for the treatment of cardiovascular and other diseases.
European journal of pharmacology 10/2010; 650(1):86-93. · 2.59 Impact Factor
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Tom G Holt,
Bernard K Choi,
Neil S Geoghagen,
Kristian K Jensen,
Qi Luo,
William A LaMarr,
Gergely M Makara, Lorraine Malkowitz,
Can C Ozbal,
Yusheng Xiong,
Claude Dufresne,
Ming-Juan Luo
[show abstract]
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ABSTRACT: Label-free mass spectrometric (MS) technologies are particularly useful for enzyme assay design for drug discovery screens. MS permits the selective detection of enzyme substrates or products in a wide range of biological matrices without need for derivatization, labeling, or capture technologies. As part of a cardiovascular drug discovery effort aimed at finding modulators of cystathionine beta-synthase (CBS), we used the RapidFire((R)) label-free high-throughput MS (HTMS) technology to develop a high-throughput screening (HTS) assay for CBS activity. The in vitro assay used HTMS to quantify the unlabeled product of the CBS reaction, cystathionine. Cystathionine HTMS analyses were carried out with a throughput of 7 s per sample and quantitation over a linear range of 80-10,000 nM. A compound library of 25,559 samples (or 80 384-well plates) was screened as singlets using the HTMS assay in a period of 8 days. With a hit rate of 0.32%, the actives showed a 90% confirmation rate. The in vitro assay was applied to secondary screens in more complex matrices with no additional analytical development. Our results show that the HTMS method was useful for screening samples containing serum, for cell-based assays, and for liver explants. The novel extension of the in vitro analytical method, without modification, to secondary assays resulted in a significant and advantageous economy of development time for the drug discovery project.
Assay and Drug Development Technologies 09/2009; 7(5):495-506. · 1.73 Impact Factor
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Dooseop Kim,
Liping Wang,
Jeffrey J Hale,
Christopher L Lynch,
Richard J Budhu,
Malcolm Maccoss,
Sander G Mills, Lorraine Malkowitz,
Sandra L Gould,
Julie A DeMartino, [......],
Daria Hazuda,
Michael Miller,
Joseph Kessler,
Renee C Hrin,
Gwen Carver,
Anthony Carella,
Karen Henry,
Janet Lineberger,
William A Schleif,
Emilio A Emini
[show abstract]
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ABSTRACT: A series of 1,3,4-trisubstituted pyrrolidine CCR5 receptor antagonists containing a variety of fused heterocycles at the 4-position of the piperidine side chain has been discovered, which are orally bioavailable with potent anti-HIV activity.
Bioorganic & Medicinal Chemistry Letters 05/2005; 15(8):2129-34. · 2.55 Impact Factor
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Shrenik K Shah,
Natalie Chen,
Ravindra N Guthikonda,
Sander G Mills, Lorraine Malkowitz,
Martin S Springer,
Sandra L Gould,
Julie A Demartino,
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael Miller,
Emilio A Emini,
Malcolm MacCoss
[show abstract]
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ABSTRACT: Synthesis of analogs containing more rigid bicyclic piperidine replacements for the 4-benzyloxycarbonyl-(ethyl)amino-piperidine moiety of the CCR5 antagonist structure, 1, is described. Although similar binding affinity to the lead was achieved with some analogs they were overall less potent anti-HIV agents suggesting that other features besides CCR5 binding are required for good anti-viral activity.
Bioorganic & Medicinal Chemistry Letters 03/2005; 15(4):977-82. · 2.55 Impact Factor
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K Shankaran,
Karla L Donnelly,
Shrenik K Shah,
Ravindra N Guthikonda,
Malcolm MacCoss,
Sander G Mills,
Sandra L Gould, Lorraine Malkowitz,
Salvatore J Siciliano,
Martin S Springer,
Anthony Carella,
Gwen Carver,
Daria Hazuda,
Karen Holmes,
Joseph Kessler,
Janet Lineberger,
Michael D Miller,
Emilio A Emini,
William A Schleif
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ABSTRACT: Efforts toward the exploration of the title compounds as CCR5 antagonists are disclosed. The basis for such work stems from the fact that cellular proliferation of HIV-1 requires the cooperative assistance of both CCR5 and CD4 receptors. The synthesis and SAR of pyrrolidineacetic acid derivatives as CCR5 antagonists displaying potent binding and antiviral properties in a HeLa cell-based HIV-1 infectivity assay are discussed.
Bioorganic & Medicinal Chemistry Letters 08/2004; 14(13):3419-24. · 2.55 Impact Factor
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K Shankaran,
Karla L Donnelly,
Shrenik K Shah,
Charles G Caldwell,
Ping Chen,
Paul E Finke,
Bryan Oates,
Malcolm MacCoss,
Sander G Mills,
Julie A DeMartino, [......],
Anthony Carella,
Gwen Carver,
Renee Danzeisen,
Daria Hazuda,
Karen Holmes,
Joseph Kessler,
Janet Lineberger,
Michael D Miller,
Emilio A Emini,
William A Schleif
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ABSTRACT: Cellular proliferation of HIV-1 requires the cooperative assistance of both the CCR5 and CD4 receptors. Our medicinal chemistry efforts in this area have resulted in the identification of N-alkyl piperidine sulfones as CCR5 antagonists. These compounds display potent binding and show antiviral properties in HIV-1 spread cell-based assays.
Bioorganic & Medicinal Chemistry Letters 08/2004; 14(13):3589-93. · 2.55 Impact Factor
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Hiranthi Jayasuriya,
Kithsiri B Herath,
John G Ondeyka,
Jon D Polishook,
Gerald F Bills,
Anne W Dombrowski,
Marty S Springer,
Sal Siciliano, Lorraine Malkowitz,
Manuel Sanchez,
Ziqiang Guan,
Suroojnauth Tiwari,
Dennis W Stevenson,
Robert P Borris,
Sheo B Singh
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ABSTRACT: Human CCR5 is a G-coupled receptor that binds to the envelope protein gp120 and CD4 and mediates the HIV-1 viral entry into the cells. The blockade of this binding by a small molecule receptor antagonist could lead to a new mode of action agent for HIV-1 and AIDS. Screening of natural product extracts led to the identification of anibamine (1), a novel pyridine quaternary alkaloid as a TFA salt, from Aniba sp.; ophiobolin C from fermentation extracts of fungi Mollisia sp.; and 19,20-epoxycytochalasin Q from Xylaria sp. Formation of the TFA salt of anibamine is plausibly an artifact of the isolation. The identity of the natural counterion is unknown. Anibamine.TFA competed for the binding of 125I-gp120 to human CCR5 with an IC50 of 1 microM. Ophiobolin C and 19,20-epoxycytochalasin Q exhibited binding IC50) values of 40 and 60 microM, respectively.
Journal of Natural Products 07/2004; 67(6):1036-8. · 3.13 Impact Factor
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Dong-Ming Shen,
Min Shu,
Sander G Mills,
Kevin T Chapman, Lorraine Malkowitz,
Martin S Springer,
Sandra L Gould,
Julie A DeMartino,
Salvatore J Siciliano,
Gloria Y Kwei,
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael D Miller,
Emilio A Emini
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ABSTRACT: Replacement of the flexible connecting chains between the piperidine moiety and an aromatic group in previous CCR5 antagonists with heterocycles, such as pyrazole and isoxazole, provided potent CCR5 antagonists with excellent anti-HIV-1 activity in vitro. SAR studies revealed optimal placement of an unsubstituted nitrogen atom in the heterocycle to be meta to the bond connected to the 4-position of piperidine. Truncation of a benzyl group to a phenyl group afforded compounds with dramatically improved oral bioavailability, albeit with reduced activity.
Bioorganic & Medicinal Chemistry Letters 03/2004; 14(4):935-9. · 2.55 Impact Factor
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Dong-Ming Shen,
Min Shu,
Christopher A Willoughby,
Shrenik Shah,
Christopher L Lynch,
Jeffrey J Hale,
Sander G Mills,
Kevin T Chapman, Lorraine Malkowitz,
Martin S Springer, [......],
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael D Miller,
Emilio A Emini
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ABSTRACT: Modifications of the alkyl acetic acid portion and the phenyl on pyrrolidine in our lead pyrazole compound 1 afforded the isopropyl compound 9. This compound is a potent CCR5 antagonist showing good in vitro antiviral activity against HIV-1, an excellent selectivity profile, and good oral bioavailability in three animal species. During this investigation, a new method for the preparation of alpha-(pyrrolidin-1-yl)-alpha,alpha-dialkyl acetic acid from a pyrrolidine and alpha-bromo-alpha,alpha-dialkyl acetic acid using silver triflate was discovered. This allowed us to prepare compounds such as 24 and 25 for the first time. A novel Pd-mediated N-dealkylation of alpha-(pyrrolidin-1-yl)acetic acid was also uncovered.
Bioorganic & Medicinal Chemistry Letters 03/2004; 14(4):941-5. · 2.55 Impact Factor
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Min Shu,
Jennifer L Loebach,
Kerry A Parker,
Sander G Mills,
Kevin T Chapman,
Dong-Ming Shen, Lorraine Malkowitz,
Martin S Springer,
Sandra L Gould,
Julie A DeMartino, [......],
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael D Miller,
Emilio A Emini
[show abstract]
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ABSTRACT: Extensive SAR studies in our benzylpyrazole series of CCR5 antagonists have shown that both lipophilic and hydrophilic substituents on the phenyl of the benzyl group increase antiviral potency. However, improvements in pharmacokinetic profiles were generally only observed with more lipophilic substitutions. 4-Biphenyl (51) performed the best in this regard. Highly lipophilic substituents impart undesirable ion channel activity to these CCR5 antagonists. Alkoxy substituents provide a good balance of antiviral activity, pharmacokinetic parameters, and selectivity. Compounds 42b and 42d, containing a 3,4-dimethoxy substituent, are considered the most promising improvements over parent compounds 9. They demonstrate improved antiviral activity while retaining good pharmacokinetic profile and selectivity.
Bioorganic & Medicinal Chemistry Letters 03/2004; 14(4):947-52. · 2.55 Impact Factor
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Christopher L Lynch,
Jeffrey J Hale,
Richard J Budhu,
Amy L Gentry,
Paul E Finke,
Charles G Caldwell,
Sander G Mills,
Malcolm MacCoss,
Dong-Ming Shen,
Kevin T Chapman, [......],
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael Miller,
Emilio Emini
[show abstract]
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ABSTRACT: [reaction: see text] A novel approach to alpha,alpha-disubstituted-beta-amino acids (beta(2,2)-amino acids) was employed in the synthesis of a series of 3-(pyrrolidin-1-yl)propionic acids possessing high affinity for the CCR5 receptor and potent anti-HIV activity. The rat pharmacokinetics for these new analogues featured higher bioavailabilities and lower rates of clearance as compared to cyclopentane 1.
Organic Letters 08/2003; 5(14):2473-5. · 5.86 Impact Factor
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Christopher A Willoughby,
Keith G Rosauer,
Jeffery J Hale,
Richard J Budhu,
Sander G Mills,
Kevin T Chapman,
Malcolm MacCoss, Lorraine Malkowitz,
Martin S Springer,
Sandra L Gould, [......],
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael Miller,
Emilio A Emini
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ABSTRACT: A new class of 4-(aminoheterocycle)piperidine derived 1,3,4 trisubstituted pyrrolidine CCR5 antagonists is reported. Compound 4a is shown to have good binding affinity (1.8 nM) and antiviral activity in PBMC's (IC(95)=50 nM). Compound 4a also has improved PK properties relative to 1.
Bioorganic & Medicinal Chemistry Letters 03/2003; 13(3):427-31. · 2.55 Impact Factor
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Christopher L Lynch,
Christopher A Willoughby,
Jeffrey J Hale,
Edward J Holson,
Richard J Budhu,
Amy L Gentry,
Keith G Rosauer,
Charles G Caldwell,
Ping Chen,
Sander G Mills, [......],
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael Miller,
Emilio A Emini
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ABSTRACT: The 4-(3-phenylprop-1-yl)piperidine moiety of the 1,3,4-trisubstituted pyrrolidine CCR5 antagonist 1 was modified with electron deficient aromatics as well as replacement of the benzylic methylene with sulfones, gem-difluoromethylenes and alcohols in an effort to balance the antiviral potency with reasonable pharmacokinetics.
Bioorganic & Medicinal Chemistry Letters 02/2003; 13(1):119-23. · 2.55 Impact Factor
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Jeffrey J Hale,
Richard J Budhu,
Sander G Mills,
Malcolm MacCoss,
Sandra L Gould,
Julie A DeMartino,
Martin S Springer,
Salvatore J Siciliano, Lorraine Malkowitz,
William A Schleif,
Daria Hazuda,
Michael Miller,
Joseph Kessler,
Renee Danzeisen,
Karen Holmes,
Janet Lineberger,
Anthony Carella,
Gwen Carver,
Emilio A Emini
[show abstract]
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ABSTRACT: Incorporation of acidic functional groups into a lead CCR5 antagonist identified from a targeted combinatorial library resulted in compounds with enhanced anti-HIV-1 activity and attenuated L-type calcium channel affinity.
Bioorganic & Medicinal Chemistry Letters 11/2002; 12(20):2997-3000. · 2.55 Impact Factor
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Christopher L Lynch,
Jeffrey J Hale,
Richard J Budhu,
Amy L Gentry,
Sander G Mills,
Kevin T Chapman,
Malcolm MacCoss, Lorraine Malkowitz,
Martin S Springer,
Sandra L Gould, [......],
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael Miller,
Emilio A Emini
[show abstract]
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ABSTRACT: A series of alpha-(pyrrolidin-1-yl)acetic acids is presented as selective and potent antivirals against HIV. Several of the pyrrolidine zwitterions demonstrated reasonable in vitro properties, enhanced antiviral activities and improved pharmacokinetic profiles over pyrrolidine 1.
Bioorganic & Medicinal Chemistry Letters 11/2002; 12(20):3001-4. · 2.55 Impact Factor
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Christopher L Lynch,
Amy L Gentry,
Jeffrey J Hale,
Sander G Mills,
Malcolm MacCoss, Lorraine Malkowitz,
Martin S Springer,
Sandra L Gould,
Julie A DeMartino,
Salvatore J Siciliano, [......],
Anthony Carella,
Gwen Carver,
Karen Holmes,
William A Schleif,
Renee Danzeisen,
Daria Hazuda,
Joseph Kessler,
Janet Lineberger,
Michael Miller,
Emilio A Emini
[show abstract]
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ABSTRACT: A series of CCR5 antagonists containing bicyclic isoxazolidines was generated through a nitrone mediated cycloaddition with olefins bearing the preferred pharmacophores previously described. Potent antagonists (3 and 16) were generated with enhanced affinity for the CCR5 receptor while maintaining antiviral activity against HIV.
Bioorganic & Medicinal Chemistry Letters 03/2002; 12(4):677-9. · 2.55 Impact Factor
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Christopher A Willoughby,
Steven M Hutchins,
Keith G Rosauer,
Madhumeeta J Dhar,
Kevin T Chapman,
Gary G Chicchi,
Sharon Sadowski,
David H Weinberg,
Smita Patel, Lorraine Malkowitz,
Jerry Di Salvo,
Stephen G Pacholok,
Kang Cheng
[show abstract]
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ABSTRACT: Preparation and screening of mixture libraries based on a 2-arylindole scaffold resulted in the discovery of potent ligands for a variety of G-protein coupled receptors.
Bioorganic & Medicinal Chemistry Letters 02/2002; 12(1):93-6. · 2.55 Impact Factor
