Table 1.

HDAC inhibitory activity of phenyl- and benzyl-capped MCAs 10–26.

Compound	Total HDAC (IC50, μM)	Class I (IC50, μM)				Class IIb (IC50, μM)
		HDAC1	HDAC2	HDAC3	HDAC8	HDAC6	HDAC10	SIb	Ref	Original No.
SAHA (1)a	0.28 (0.08)	0.03	0.94	0.25	0.64	0.033	0.30	1	[70, 71]	–
TSA (9)a	0.004	0.004	0.014	0.002	1.38	0.001	0.005	4	[71]	–
10	11.00	n.a.c	n.a.	n.a.	n.a.	n.a.	n.a.	n.d.d	[70]	5c
11a	0.39 (0.30, 2.44)	3.76	>30	n.a.	14.1 (200, 3.89)	0.34	>30	11.1	[70-72, 74]	5b, 10e, 4, 1a
12	3.00 (0.15)	n.a.	n.a.	n.a.	0.69	n.a.	n.a.	n.d.	[70]	5a, 7
13a	1.10	3.36	18.8	n.a.	7.53	0.19	8.71	17.6	[71]	4h
14a	0.90	2.42	10.4	n.a.	8.75	0.54	5.24	4.5	[71]	4i
15a	0.75	2.60	15.6	n.a.	11.4	0.52	4.34	5	[71]	5c
16	0.63	10.9	>30	n.a.	13.9	2.01	>30	5.4	[71, 73]	5d, 6
17a	1.00	5.18	>30	n.a.	11.0	1.16	9.26	4.5	[71]	5e
18	0.80	5.26	>30	n.a.	12.3	0.22	8.78	23.9	[71, 73]	4a, 13
19	4.70	11.9	>30	n.a.	>30	0.62	29.7	19.2	[71, 73]	4b, 12
20	0.20	1.08	6.46	n.a.	10.2	0.11	1.54	9.8	[71, 73]	4c, 11
21	0.45	1.43	4.64	n.a.	19.1	0.48	3.43	3	[71, 73]	4d, 7
22a	0.60	5.38	17.0	n.a.	15.6	0.32	17.7	16.8	[71]	10a
23a	1.70e	2.82	>30	n.a.	n.a.	0.68	4.61	4.1	[75]	BC-4-93
24	1.70	n.a.	n.a.	n.a.	n.a.	n.a.	n.a.	n.d.	[71]	5a
25	5.00	n.a.	n.a.	n.a.	n.a.	n.a.	n.a.	n.d.	[71]	5b
26a	0.20	14.7	>30	n.a.	16.7	1.54	>30	9.5	[71]	4k

^aUnpublished HDAC isoform enzymatic data. IC₅₀ values are the mean of two experiments obtained from curve-fitting of a 10-point enzymatic assay starting from 30 μM with 3-fold serial dilution against HDACs (Reaction Biology Corp, Malvern, PA).

^bSI, HDAC1/6 selectivity index.

^cn.a., not available.

^dn.d., not determined.

^eIC₅₀ value was calculated from pIC₅₀ value.