Table 2.

PDE inhibiting activity of selected compounds.

Cmpd	R1	R2	Y	M.W.	cLogPa	tPSAa	G.l. IC50 (nM)b	GlPDE Ki (nM)c	hPDE4B Ki (nM)c
11	NO2	MeO	Y1	531.6	3.3	127.7	0.5 ± 0.2	500 ± 300	0.16 ± 0.02
18	NO2	MeO	Y3	479.5	2.1	127.7	0.2 ± 0.1	>104	3.2 ± 0.4
19	NO2	Cl	Y3	483.9	2.9	118.5	19.0 ± 3.2	>106	200 ± 50
20	H	MeO	Y3	434.5	2.1	84.5	930 ± 100	>106	5.0 ± 1.0

^acLogP, tPSA are calculated using CDD Vault.

^bmean values ± standard errors are given for quadruplicates, the standard errors correspond to the 95% confidence intervals as calculated via the logit-log algorithm.

^cmean values ± standard deviations, n ≥ 2.