Figure 1.
Previously reported HDAC3-selective inhibitors 1 and 2.
Figure 2.
Design of triazole-containing HDAC inhibitor candidates.
Figure 3.
Scheme for the synthesis of Az1–Az5, Az7, and Az11.
Reagents and conditions: (a) NaN3, CuI, l-Pro, NaOH, DMSO, 60°C, 37–95%.
Figure 4.
Scheme for the synthesis of Az6, Az8–Az10, and Az12.
Reagents and conditions: (a) i) NaNO2, H2O, TFA, 0°C; ii) NaN3, H2O, 0°C to room temp, 18–90%.
Figure 5.
Scheme for the synthesis of Az13 and Az14.
Reagents and conditions: (a) NaN3, DMSO, room temp, 97% for Az13; 64% for Az14.
Figure 6.
Scheme for the synthesis of Ak1–Ak3.
Reagents and conditions: (a) EDCI, HOBt, DMF, room temp, 36–62%.
Figure 7.
Inhibition of HDAC3 in the presence of T1–T504 (10 µM for o-aminoanilides T1–T336; 1 µM for hydroxamates T337–T504).
o-Aminoanilides inhibiting more than 90% of HDAC3 activity and hydroxamates inhibiting more than 60% of HDAC3 activity are indicated in red. Vorinostat (3) (1 µM) and compound 1 (10 µM) inhibited 98% and 47% of HDAC3 activity, respectively.
Figure 8.
Total HDACs activity in the presence of 48 hydroxamates (1 µM).
Figure 9.
Activity of total HDACs in the presence of 59 o-aminoanilides (10 µM).
Table 1.
HDAC3 inhibition in the presence of vorinostat (3), compound 1, and 11 o-aminoanilides at 1 µM and 3 µM.a
Figure 10.
Scheme for the synthesis of T247 and T326.
Reagents and conditions: (a) CuSO4, sodium ascorbate, EtOH, H2O, room temp, 65% for T247; 97% for T326.
Table 2.
HDAC-Inhibitory Activity of vorinostat (3), compound 1, T247, and T326 a.
Figure 11.
(A) View of the conformation of T247 (tube) docked in the HDAC3 catalytic core. Compound T247 was docked into a model based on the crystal structure of HDAC3 (PDB code 4A69) using the Molegro Virtual Docker software package. Residues around T247 are displayed as wires. (B) The same view as A. The narrow and long tunnel of the active site is displayed as a green mesh. (C) Schematic diagram of T247-binding to the catalytic site.
Figure 12.
Western blot detection of acetylated NF-κB, p53, and α-tubulin levels in HCT116 cells after 8 h treatment with vorinostat (3), compound 1, T247, and T326.
Table 3.
Growth inhibition of colon cancer HCT116 cells and prostate cancer PC3 cells by vorinostat (3), compound 1, T247, and T326a.
Figure 13.
Induction of viral replication from OM10.1 cells latently infected with HIV-1.
Cells were incubated with compound 1, vorinostat (3), T247, and T326 for 48 h. HIV-1 p24 antigen in the cell culture supernatant was measured using ELISA. Experiments were performed in triplicate, and the means ±S.D. are indicated. **P<0.01, *P<0.05; Student’s t test results indicated differences between DMSO and inhibitors.