Objective

To test the inhibitory activity of Ugi products 148B and 150D (Ugi product Exp150)against falcipain-2. For a summary of the project refer to this post.

Contributors

Jiri Gut from the Rosenthal group performed these experiments.

Procedure

The compounds are dissolved in DMSO as 10 mM stock then diluted 1:100 into 100 mM acetate buffer (pH 6.0) then pre-incubated with the falcipain-2 enzyme. Fluorogenic substrate is then added (Z-LEU-ARG-aminomethylcoumarin) and the signal read over time. The results are expressed as percent of control (DMSO), and IC 50 calculated.

Results

compound
Test 1 IC50(nM)
SD
Test 2 IC50(nM)
SD
148B
5284
344
19655
1874
150D
4718
448
16660
2319
E64
105.55
2.3
64
2

Discussion


The 2 Ugi products exhibited similar activity. In the first test the compounds were about 50 times less active than the Rosenthal positive control E64. In the second test they were about 300 times less active than E64.
It is unclear why the activities of both compounds decreased about fourfold in the second run. Compounds were stored as DMSO solutions at -20C. Degradation over time is one possibility but the fact that these are essentially insoluble in water may render the experiments less reproducible.
Further studies in liposomal formulations should be performed to overcome the solubility problem.

Conclusion

Both Ugi products proved to be inhibitors of falcipain-2 with IC-50s in the range of 4.7-19.7 micromolar.

Log



Tags


Phenanthrene-9-carboxaldehydeInChI=1/C15H10O/c16-10-12-9-11-5-1-2-6-13(11)15-8-4-3-7-14(12)15/h1-10H InChIKey: QECIGCMPORCORE-UHFFFAOYAE
tert-butylisocyanideInChI=1/C5H9N/c1-5(2,3)6-4/h1-3H3 InChIKey: FAGLEPBREOXSAC-UHFFFAOYAL
Crotonic Acid: InChI=1/C4H6O2/c1-2-3-4(5)6/h2-3H,1H3,(H,5,6)/f/h5H InChIKey: LDHQCZJRKDOVOX-UHFFFAOYAC
n-Heptylamine : InChI=1/C7H17N/c1-2-3-4-5-6-7-8/h2-8H2,1H3 InChIKey: WJYIASZWHGOTOU-UHFFFAOYAD
targetUgiExp148:InChI=1/C31H40N2O2/c1-6-8-9-10-15-21-33(28(34)16-7-2)29(30(35)32-31(3,4)5)
27-22-23-17-11-12-18-24(23)25-19-13-14-20-26(25)27/h7,11-14,16-20,22,29H,6,8-10,15,21H2,1-5H3,(H,32,35)/b16-7

Phenanthrene-9-carboxaldehydeInChI=1/C15H10O/c16-10-12-9-11-5-1-2-6-13(11)15-8-4-3-7-14(12)15/h1-10H InChIKey: QECIGCMPORCORE-UHFFFAOYAE
tert-butylisocyanideInChI=1/C5H9N/c1-5(2,3)6-4/h1-3H3 InChIKey: FAGLEPBREOXSAC-UHFFFAOYAL
Crotonic Acid: InChI=1/C4H6O2/c1-2-3-4(5)6/h2-3H,1H3,(H,5,6)/f/h5H InChIKey: LDHQCZJRKDOVOX-UHFFFAOYAC
benzylamine InChI=1/C7H9N/c8-6-7-4-2-1-3-5-7/h1-5H,6,8H2 InChIKey: WGQKYBSKWIADBV-UHFFFAOYAL
Ugi Product