. Author manuscript; available in PMC: 2014 Jun 1.

Published in final edited form as: Bioorg Med Chem Lett. 2013 Apr 4;23(11):3283–3287. doi: 10.1016/j.bmcl.2013.03.108

Table 1.

In vitro HDAC inhibition activity of novel HDAC-Topo I inhibitors.

graphic file with name nihms-463939-t0006.jpg

Compound	n	R¹	HeLa^a IC₅₀ (nM)	HDAC 1^b IC₅₀ (nM)	HDAC 6^b IC₅₀ (nM)	HDAC 8^b IC₅₀ (nM)
5a	1	-CH₂CH₃	N.D.	N.D.	85 ± 34	1726 ± 577
5b	2	-CH₂CH₃	155.4	NT	NT	NT
5c	3	-CH₂CH₃	120.7	129 ± 33	42 ± 6	N.D.
5d	4	-CH₂CH₃	64.65	50 ± 7	36 ± 5	N.D.
5e	5	-CH₂CH₃	212.3	369 ± 111	75 ± 34	2599 ± 475
5f	2	-H	144.5	116 ± 40	260 ± 40	N.D.
5g	3	-H	112.2	N.T.	N.T.	N.T.
5h	4	-H	56.2	37 ± 7	81 ± 26	1046 ± 316
SN-38	-	-	N.D.	N.T.	N.T.	N.T.
SAHA	-	-	65.0	38 ± 2	27 ± 2	1989 ± 156

N.D. – Nondeterminable within tested range, 1 nM – 10 μM; N. T – Not tested.

HeLa nuclear extract. Each value is obtained from three independent experiments.

Data obtained through contract arrangement with BPS Bioscience (San Diego, USA; www.bpsbioscience.com). Assays were performed in duplicates at each concentration and data reported with standard error.^{29, 34c}