Pyridinium-1-yl Bisphosphonates Are Potent Inhibitors of Farnesyl Diphosphate Synthase and Bone Resorption (original) (raw)

3-D QSAR Investigations of the Inhibition of Leishmania major Farnesyl Pyrophosphate Synthase by Bisphosphonates

Journal of Medicinal Chemistry, 2003

We report the activities of 62 bisphosphonates as inhibitors of the Leishmania major mevalonate/isoprene biosynthesis pathway enzyme, farnesyl pyrophosphate synthase. The compounds investigated exhibit activities (IC 50 values) ranging from ∼100 nM to ∼80 µM (corresponding to K i values as low as 10 nM). The most active compounds were found to be zoledronate (whose single-crystal X-ray structure is reported), pyridinyl-ethane-1-hydroxy-1,1bisphosphonates or picolyl aminomethylene bisphosphonates. However, N-alicyclic aminomethylene bisphosphonates, such as incadronate (N-cycloheptyl aminomethylene bisphosphonate), as well as aliphatic aminomethylene bisphosphonates containing short (n) 4, 5) alkyl chains, were also active, with IC 50 values in the 200-1700 nM range (corresponding to K i values of ∼20-170 nM). Bisphosphonates containing longer or multiple (N,N-) alkyl substitutions were inactive, as were aromatic species lacking an o-or m-nitrogen atom in the ring, or possessing multiple halogen substitutions or a p-amino group. To put these observations on a more quantitative structural basis, we used three-dimensional quantitative structure-activity relationship techniques: comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA), to investigate which structural features correlated with high activity. Training set results (N) 62 compounds) yielded good correlations with each technique (R 2) 0.87 and 0.88, respectively), and were further validated by using a training/test set approach. Test set results (N) 24 compounds) indicated that IC 50 values could be predicted within factors of 2.9 and 2.7 for the CoMFA and CoMSIA methods, respectively. The CoMSIA fields indicated that a positive charge in the bisphosphonate side chain and a hydrophobic feature contributed significantly to activity. Overall, these results are of general interest since they represent the first detailed quantitative structure-activity relationship study of the inhibition of an expressed farnesyl pyrophosphate synthase enzyme by bisphosphonate inhibitors and that the activity of these inhibitors can be predicted within about a factor of 3 by using 3D-QSAR techniques.

Structural and thermodynamic basis of the inhibition ofLeishmania majorfarnesyl diphosphate synthase by nitrogen-containing bisphosphonates

Acta Crystallographica Section D Biological Crystallography, 2014

Farnesyl diphosphate synthase (FPPS) is an essential enzyme involved in the biosynthesis of sterols (cholesterol in humans and ergosterol in yeasts, fungi and trypanosomatid parasites) as well as in protein prenylation. It is inhibited by bisphosphonates, a class of drugs used in humans to treat diverse bone-related diseases. The development of bisphosphonates as antiparasitic compounds targeting ergosterol biosynthesis has become an important route for therapeutic intervention. Here, the X-ray crystallographic structures of complexes of FPPS fromLeishmania major(the causative agent of cutaneous leishmaniasis) with three bisphosphonates determined at resolutions of 1.8, 1.9 and 2.3 Å are reported. Two of the inhibitors, 1-(2-hydroxy-2,2-diphosphonoethyl)-3-phenylpyridinium (300B) and 3-butyl-1-(2,2-diphosphonoethyl)pyridinium (476A), co-crystallize with the homoallylic substrate isopentenyl diphosphate (IPP) and three Ca2+ions. A third inhibitor, 3-fluoro-1-(2-hydroxy-2,2-diphosphon...

Phosphonate and Bisphosphonate Inhibitors of Farnesyl Pyrophosphate Synthases: A Structure-Guided Perspective

Frontiers in Chemistry, 2021

Phosphonates and bisphosphonates have proven their pharmacological utility as inhibitors of enzymes that metabolize phosphate and pyrophosphate substrates. The blockbuster class of drugs nitrogen-containing bisphosphonates represent one of the best-known examples. Widely used to treat bone-resorption disorders, these drugs work by inhibiting the enzyme farnesyl pyrophosphate synthase. Playing a key role in the isoprenoid biosynthetic pathway, this enzyme is also a potential anticancer target. Here, we provide a comprehensive overview of the research efforts to identify new inhibitors of farnesyl pyrophosphate synthase for various therapeutic applications. While the majority of these efforts have been directed against the human enzyme, some have been targeted on its homologs from other organisms, such as protozoan parasites and insects. Our particular focus is on the structures of the target enzymes and how the structural information has guided the drug discovery efforts.

Inhibition of Geranylgeranyl Diphosphate Synthase by Bisphosphonates and Diphosphates: A Potential Route to New Bone Antiresorption and Antiparasitic Agents

Journal of Medicinal Chemistry, 2002

We report the X-ray structures of several bisphosphonate inhibitors of geranylgeranyl diphosphate synthase, a target for anticancer drugs. Bisphosphonates containing unbranched side chains bind to either the farnesyl diphosphate (FPP) substrate site, the geranylgeranyl diphosphate (GGPP) product site, and in one case, both sites, with the bisphosphonate moiety interacting with 3 Mg 2+ that occupy the same position as found in FPP synthase. However, each of three "V-shaped" bisphosphonates bind to both the FPP and GGPP sites. Using the Glide program, we reproduced the binding modes of 10 bisphosphonates with an rms error of 1.3 Å. Activities of the bisphosphonates in GGPPS inhibition were predicted with an overall error of 2× by using a comparative molecular similarity analysis based on a docked-structure alignment. These results show that some GGPPS inhibitors can occupy both substrate and product site and that binding modes as well as activity can be accurately predicted, facilitating the further development of GGPPS inhibitors as anticancer agents. † Crystal structure coordinates have been deposited in the Protein Data Bank and will be released upon publication (2z4w, 2z4z, 2z78, 2z4x, 2z4y, 2z50, 2z52, 2z4v, 2z71).

Identification of a Bisphosphonate That Inhibits Isopentenyl Diphosphate Isomerase and Farnesyl Diphosphate Synthase

Biochemical and Biophysical Research Communications, 2002

We and others have recently shown that the major molecular target of nitrogen-containing bisphosphonate drugs is farnesyl diphosphate synthase, an enzyme in the mevalonate pathway. In an in vitro screen, we discovered a bisphosphonate, NE21650, that potently inhibited farnesyl diphosphate synthase but, unlike other N-BPs investigated, was also a weak inhibitor of isopentenyl diphosphate isomerase. NE21650 was a more potent inhibitor of protein prenylation in osteoclasts and macrophages, and a more potent inhibitor of bone resorption in vitro, than alendronate, despite very similar IC 50 values for inhibition of farnesyl diphosphate synthase. Our observations show that minor changes to the structure of bisphosphonates allow inhibition of more than one enzyme in the mevalonate pathway and suggest that loss of protein prenylation due to inhibition of more than one enzyme in the mevalonate pathway may lead to an increase in antiresorptive potency compared to bisphosphonates that only inhibit farnesyl diphosphate synthase.

Structure–Activity Relationships Among the Nitrogen Containing Bisphosphonates in Clinical Use and Other Analogues: Time-Dependent Inhibition of Human Farnesyl Pyrophosphate Synthase

Journal of Medicinal Chemistry, 2008

The nitrogen-containing bisphosphonates (N-BPs) are the main drugs currently used to treat diseases characterized by excessive bone resorption. The major molecular target of N-BPs is farnesylpyrophosphate synthase. N-BPs inhibit the enzyme by a mechanism that involves time dependent isomerization of the enzyme. We investigated features of N-BPs that confer maximal slow and tight-binding by quantifying the initial and final K i s and calculating the isomerization constant K isom for many N-BPs. Disruption of the phosphonate-carbon-phosphonate backbone resulted in loss of potency and reduced K isom. The lack of a hydroxyl group on the geminal carbon also reduced K isom. The position of the nitrogen in the side chain was crucial to both K i and K isom. A correlation of K isom and also final K i with previously published in vivo potency reveals that the isomerization constant (R)-0.77, p < 0.0001) and the final inhibition of FPPS by N-BPs (R) 0.74, p < 0.0001) are closely linked to antiresorptive efficacy.

Lipophilic Bisphosphonates as Dual Farnesyl/Geranylgeranyl Diphosphate Synthase Inhibitors: An X-ray and NMR Investigation

Journal of the American Chemical Society, 2009

Considerable effort has focused on the development of selective protein farnesyl transferase (FTase) and protein geranylgeranyl transferase (GGTase) inhibitors as cancer chemotherapeutics. Here, we report a new strategy for anti-cancer therapeutic agents involving inhibition of farnesyl diphosphate synthase (FPPS) and geranylgeranyl diphosphate synthase (GGPPS), the two enzymes upstream of FTase and GGTase, by lipophilic bisphosphonates. Due to dual site targeting and decreased polarity, the compounds have activities far greater than do current bisphosphonate drugs in inhibiting tumor cell growth and invasiveness, both in vitro and in vivo. We explore how these compounds inhibit cell growth, how cell activity can be predicted based on enzyme inhibition data, and, using x-ray diffraction, solid state NMR and isothermal titration calorimetry, we show how these compounds bind to FPPS and/or GGPPS.

Bisphosphonate-Based Molecules as Potential New Antiparasitic Drugs

Molecules

Neglected tropical diseases such as Chagas disease and leishmaniasis affect millions of people around the world. Both diseases affect various parts of the globe and drugs traditionally used in therapy against these diseases have limitations, especially with regard to low efficacy and high toxicity. In this context, the class of bisphosphonate-based compounds has made significant advances regarding the chemical synthesis process as well as the pharmacological properties attributed to these compounds. Among this spectrum of pharmacological activity, bisphosphonate compounds with antiparasitic activity stand out, especially in the treatment of Chagas disease and leishmaniasis caused by Trypanosoma cruzi and Leishmania spp., respectively. Some bisphosphonate compounds can inhibit the mevalonate pathway, an essential metabolic pathway, by interfering with the synthesis of ergosterol, a sterol responsible for the growth and viability of these parasites. Therefore, this review aims to pres...

New insights into molecular recognition of 1,1-bisphosphonic acids by farnesyl diphosphate synthase

Bioorganic & Medicinal Chemistry, 2014

As part of our project pointed at the search of new antiparasitic agents against American trypanosomiasis (Chagas disease) and toxoplasmosis a series of 2-alkylaminoethyl-1-hydroxy-1,1bishosphonic acids has been designed, synthesized and biologically evaluated against the etiologic agents of these parasitic diseases, Trypanosoma cruzi and Toxoplasma gondii, respectively, and also towards their target enzymes, T. cruzi and T. gondii farnesyl pyrophosphate synthase (FPPS), respectively. Surprisingly, while most pharmacologically active bisphosphonates have a hydroxyl group at the C-1 position, the additional presence of an amino group at C-3 resulted in decreased activity towards either T. cruzi cells or TcFPPS. Density functional theory calculations justify this unexpected behavior. Although these compounds were devoid of activity against T. cruzi cells and TcFPPS, they were efficient growth inhibitors of tachyzoites of T. gondii. This activity was associated with a potent inhibition of the enzymatic activity of TgFPPS. Compound 28 arises as a main example of this family of compounds exhibiting an ED 50 value of 4.7 μM against tachyzoites of T. gondii and an IC 50 of 0.051 μM against TgFPPS.