Structure-activity relationship of short-chain sphingoid bases as inhibitors of sphingosine kinase (original) (raw)

Synthesis and evaluation of sphingoid analogs as inhibitors of sphingosine kinases

Bioorganic & Medicinal Chemistry, 2005

Sphingosine 1-phosphate (S1P), a product of sphingosine kinases (SphK), mediates diverse biological processes such as cell differentiation, proliferation, motility and apoptosis. In an effort to search and identify specific inhibitors of human SphK, the inhibitory effects of synthetic sphingoid analogs on kinase activity were examined.

Design, synthesis and biological activity of sphingosine kinase 2 selective inhibitors

Bioorganic & Medicinal Chemistry, 2012

Sphingosine kinase (SphK) has emerged as an attractive target for cancer therapeutics due to its role in cell survival. SphK phosphorylates sphingosine to form sphingosine 1-phosphate (S1P), which has been implicated in cancer growth and survival. SphK exists as two different isotypes, namely SphK1 and SphK2, which play different roles inside the cell. In this report, we describe SphK inhibitors based on the immunomodulatory drug, FTY720, which is phosphorylated by SphK2 to generate a S1P mimic. Structural modification of FTY720 provided a template for synthesizing new inhibitors. A diversity-oriented synthesis generated a library of SphK inhibitors with a novel scaffold and headgroup. We have discovered subtype selective inhibitors with K i 's in the low micromolar range. This is the first report describing quaternary ammonium salts as SphK inhibitors.

Iodophenyl tagged sphingosine derivatives: Synthesis and preliminary biological evaluation

Bioorganic & Medicinal Chemistry Letters, 2009

A facile synthesis of six 4-iodophenyl tagged sphingosine (SP) derivatives bearing alkyl chain lengths from 6 to 13 is described. The key steps for the assembly of these molecules, 5a-f, are Suzuki-Miyaura cross-coupling and cross-metathesis reactions. The feasibility of radiolabeling was demonstrated by synthesizing two 125 I labeled compounds, [ 125 I]5c and [ 125 I]5e. In vitro enzyme assays indicated that the molecules, 5c-e, are potent inhibitors. Thus, they deserve further evaluation as potential radioactive probes for tumor imaging.

Structure−Activity Relationship Studies and in Vivo Activity of Guanidine-Based Sphingosine Kinase Inhibitors: Discovery of SphK1- and SphK2-Selective Inhibitors

Journal of Medicinal Chemistry, 2015

Sphingosine 1-phosphate (S1P) is a pleiotropic signaling molecule that acts as a ligand for five Gprotein coupled receptors (S1P 1-5) whose downstream effects are implicated in a variety of important pathologies including sickle cell disease, cancer, inflammation, and fibrosis. The synthesis of S1P is catalyzed by sphingosine kinase (SphK) isoforms 1 and 2, and hence, inhibitors of this phosphorylation step are pivotal in understanding the physiological functions of SphKs. To date, SphK1 and 2 inhibitors with the potency, selectivity, and in vivo stability necessary to determine the potential of these kinases as therapeutic targets are lacking. Herein, we report the design, synthesis, and structure-activity relationship studies of guanidine-based SphK inhibitors bearing an oxadiazole ring in the scaffold. Our studies demonstrate that SLP120701, a SphK2-selective inhibitor (K i = 1 μM), decreases S1P levels in histiocytic lymphoma (U937) cells. Surprisingly, homologation with a single methylene unit between the oxadiazole and heterocyclic *

Synthesis of selective inhibitors of sphingosine kinase 1

Chemical Communications, 2013

Sphingosine kinase isoform 1 (SK1) inhibitors may serve as therapeutic agents for proliferative diseases, including hypertension. We synthesized a series of sphingosine-based SK1-selective inhibitors, the most potent of which is RB-005 (IC 50 = 3.6 lM), which also induced proteasomal degradation of SK1 in human pulmonary arterial smooth muscle cells.

Design and Development of Novel Urea, Sulfonyltriurea, and Sulfonamide Derivatives as Potential Inhibitors of Sphingosine Kinase 1

Pharmaceuticals

Sphingosine kinase 1 (SphK1) is one of the well-studied drug targets for cancer and inflammatory diseases. Recently discovered small-molecule inhibitors of SphK1 have been recommended in cancer therapeutics; however, selectivity and potency of first-generation inhibitors are great challenge. In search of effective SphK1 inhibitors, a set of small molecules have been designed and synthesized bearing urea, sulfonylurea, sulfonamide, and sulfonyltriurea groups. The binding affinity of these inhibitors was measured by fluorescence-binding assay and isothermal titration calorimetry. Compounds 1, 5, 6, and 7 showed an admirable binding affinity to the SphK1 in the sub-micromolar range and significantly inhibited SphK1 activity with admirable IC50 values. Molecular docking studies revealed that these compounds fit well into the sphingosine binding pocket of SphK1 and formed significant number of hydrogen bonds and van der Waals interactions. These molecules may be exploited as potent and s...

Fluorescence-labeled sphingosines as substrates of sphingosine kinases 1 and 2

Bioorganic & Medicinal Chemistry Letters, 2004

Fluorescently labeled d-erythro-sphingosines have been successfully synthesized in 9 and 12 steps starting from commercially available Garner aldehyde. Determining the influence of the nature, position and linkage of the label on the in vitro phosphorylation rate by sphingosine kinases 1 and 2 resulted in the identification of a pyrene-and a NBD-labeled sphingosine which are both phosphorylated with efficiency comparable to the natural substrate. #

Synthesis and bioactivity of sphingosine kinase inhibitors and their novel aspirinyl conjugated analogs

European Journal of Medicinal Chemistry, 2010

Sphingosine kinase (SphK) is a lipid kinase with oncogenic activity, and SphK inhibitors (SKIs) are known for their anti-cancer activity. Here, we report highly efficient syntheses of SKIs and their aspirinyl (Asp) analogs. Both SKIs and their Asp analogs were highly cytotoxic towards multiple human cancer cell lines; in several cases the Asp analogs were up to three times more effective. Furthermore, they were equally potent inhibitors of SphK. The pharmacokinetic study indicated that SKI-I-Asp cleaved efficiently to form SKI-I and the half-life of SKI-I was increased from w7 h in SKI-I to w10 h in SKI-I-Asp injected mice, thereby prolonging its effect. In summary, the Asp-conjugated SKIs seem to be promising prodrugs of SKIs where delivery in vivo remains a problem.