A novel series of IKKβ inhibitors part II: description of a potent and pharmacologically active series of analogs

A novel series of (E)-1-((2-(1-methyl-1H-imidazol-5-yl) quinolin-4-yl) methylene) thiosemicarbazides was discovered as potent inhibitors of IKKβ. In this Letter we document our efforts at further optimization of this series, culminating in 2 with submicromolar potency in a HWB assay and efficacy in a CIA mouse model.     

Synthesis and evaluation of [¹¹C]Cimbi-806 as a potential PET ligand for 5-HT₇ receptor imaging

2-(2',6'-Dimethoxy-[1,1'-biphenyl]-3-yl)-N,N-dimethylethanamine has been identified as a potent ligand for the serotonin 7 (5-HT(7)) receptor. In this study, we describe the synthesis, radiolabeling and in vivo evaluation of [(11)C]2-(2',6'-dimethoxy-[1,1'-biphenyl]-3-yl)-N,N-dimethylethanamine ([(11)C]Cimbi-806) as a radioligand for imaging brain 5-HT(7) receptors with positron emission tomography (PET). Precursor and reference compound was synthesized and subsequent (11)C-labelling with [(11)C]methyltriflate produced [(11)C]Cimbi-806 in specific activities ranging from 50 to 300 GBq/μmol. Following intravenous injection, brain uptake and distribution of [(11)C]Cimbi-806 was assessed with PET in Danish Landrace pigs. The time-activity curves revealed high brain uptake in thalamic and striatal regions (SUV ～2.5) and kinetic modeling resulted in distribution volumes (V(T)) ranging from 6 mL/cm(3) in the cerebellum to 12 mL/cm(3) in the thalamus. Pretreatment with the 5-HT(7) receptor antagonist SB-269970 did not result in any significant changes in [(11)C]Cimbi-806 binding in any of the analyzed regions. Despite the high brain uptake and relevant distribution pattern, the absence of appropriate in vivo blocking with a 5-HT(7) receptor selective compounds renders the conclusion that [(11)C]Cimbi-806 is not an appropriate PET radioligand for imaging the 5-HT(7) receptor in vivo.     

Development of a simple proton nuclear magnetic resonance-based procedure to estimate the approximate distribution coefficient at physiological pH (log D7.4): Evaluation and comparison to existing practices

In drug discovery, lipophilicity is a key parameter for drug optimization. Lipophilicity determinations can be both work and time consuming, especially for non-UV active compounds. Herein, an improved and simple 1H NMR-based method is described to estimate the lipophilicity at physiological pH (log D_7.4) in 1-octanol and D₂O buffer. The method can be applied to both UV and non-UV active compounds. In addition, neither calibration curves nor internal/external standards are needed. We have demonstrated that log D_7.4 can be accurately measured using 1H NMR for compounds within the log D_7.4 interval between 0.7 and 3.3. The method was also compared to a previously described HPLC method.     

Antagonistic reactions of arginine and lysine against formaldehyde and their relation to cell proliferation,apoptosis, folate cycle and photosynthesis

¹H, ¹³C NMR, ESMS and MS/MS investigations proved that there is an antagonism in the spontaneous reaction of formaldehyde with L-lysine and L-arginine. L-Arginine can only be hydroxymethylated on the guanidino group in a very fast reaction forming mono-, di-, and trihydroxymethyl arginines (HMA). L-Lysine can be methylated on the -amino group forming mono-, di-, and trimethyl lysine on physiological pH. Hydroxymethyl arginines are relative stable, isolable products, and can also be formed in biological systems, especially in plants. Significant amounts of hydroxymethyl arginines were identified in the aqueous extract of lyophilized kohlrabi, which can be formed in photosynthesis during CO₂ fixation. ¹⁴C-Formaldehyde formed in a short-term (10, 30 sec) ¹⁴CO₂ fixation reaction in Zea mays L. (early maturity variety: Szegedi TC 277) was captured by L-arginine, which occurs in leaves in large amount. Formaldehyde formed during photosynthesis can react not only with the arginine, but with ribulose-1,5-diphosphate present in leaves. In model reactions formaldehyde can react with the ene diole group of ribulose-1,5-diphosphate in the absence of Rubisco enzyme, which is a similar reaction to the addition of formaldehyde to L-ascorbic acid. Hydroxymethyl arginines (HMA) are endogenous formaldehyde carrier molecules transferring the bound formaldehyde to thymidylate synthase enzyme system incorporating it into the folate cycle. HMA can also carry the bound formaldehyde to the cells especially to the tumorous cells (HT29 adenocarcinoma), and cause significant inhibition of cell proliferation and causes apoptosis.     

Toxicity of S-metolachlor containing formulation and heavy metals to chicken embryos

Environmental pollution of metal modelled by copper sulphate, cadmium sulphate and a 960 g/l S-metolachlor containing herbicide formulation (Dual Gold 960 EC) were studied on chicken embryos after administration as a single compounds or in combination. The test materials were injected into the air-chamber in a volume of 0.1 ml/egg on day 0 of incubation. The concentration of copper, and cadmium sulphate was 0.01%. The applied concentration of Dual Gold 960 EC was 0.375%. Evaluation was done on day 19 of the hatching period. In comparison with the values of the control group, the rate of embryomortality also increased significantly in the groups which were treated by herbicide and heavy metals individually. When the herbicide (Dual Gold 960 EC) was used individually, one quarter of the treated animals died in comparison with the values measured in the control group. In the groups which were treated with cadmium sulphate and Dual Gold 960 EC embryomortality increased significantly in comparison with both the control and individually treated groups. In the groups, which were treated together, the occurrence of development disorders remained as low level as in the case individual treatments. Looking at the types of development disorders, the most frequent problems were the oedema, the shortening of the beak mandible, and the incorrect posture of the feet and the neck. As the collective result of the treatment with cadmium sulphate and Dual Gold 960 EC, the body mass of the treated embryos decreased significantly in comparison with the control and individually treated groups, therefore we can conclude that the combined treatment resulted in increased embryo toxic effect in comparison with the individual embryo damaging effect of the used components.     

The dual-function hamster receptor for amphotropic murine leukemia virus (MuLV), 10A1 MuLV, and gibbon ape leukemia virus is a phosphate symporter.

Previously, we showed that the amphotropic receptor homolog in hamster cells functions as a receptor not only for amphotropic murine leukemia viruses and 10A1 murine leukemia virus but also for gibbon ape leukemia virus (C.A. Wilson, K. B. Farrell, and M. V. Eiden, J. Virol. 68:7697-7703, 1994). Here, we demonstrate that this receptor functions as a sodium-dependent Pi transporter and that Na-Pi uptake can be specifically blocked following infection with either amphotropic murine leukemia virus, 10A1 murine leukemia virus, or gibbon ape leukemia virus.