6410 Journal of Medicinal Chemistry, 2006, Vol. 49, No. 21
Brief Articles
Table 1. Affinities(Ki, nM) for Dopamine Receptor D1-D5 Subtypes Determined by Radioligand Binding Experiments
Ki (nM)
compd
HEK D1
CHO D2L
CHO D3
CHO D4.4
HEK D5
1 (LE-300)
2 (LE-CE-580)
3 (LE-CE-560)
10
1.9 ( 0.9a
163.5b
2.2b
44.5 ( 15.8a
143 ( 127a
14.5b
25.9b
108 ( 39a
184b
7.5 ( 0.3a
92b
521 ( 239a
277.5b
NAc
98.4b
0.61b
NAc
NAc
NAc
NAc
17
NAc
NAc
NAc
NAc
NAc
a Ki values are the means of three experiments, performed in triplicate ( SEM. b Ki values are the means of two experiments, performed in triplicate.
c NA ) no activity. Less than 70% radioligand displacement of a 10-5 M solution.
Table 2. Inhibitor Activities (Ki, NM) at Dopamine Receptor D1, D2,
and D5 Subtypes Generated by a Functional Calcium Assay
respectively, which were converted into their HCl salt from diethyl
ether with ethereal HCl. Yields: 82% for 3 and 93% for 2,
respectively.
Ki (nM)
compd
HEK D1
HEK D2L
HEK D5
Acknowledgment. We thank Ba¨rbel Schmalwasser, Petra
Wiecha, and Heidi Traber for skillful technical assistance
performing the pharmacological assays.
1
2
3
10
17
60.4 ( 20.4a
304b
19.0 ( 11.7a
38b
12.7 ( 6.35a
71.6b
2.8 ( 2.4a
NAc
1.5b
2.8b
NAc
NAc
NAc
NAc
NAc
Supporting Information Available: Synthetic procedures and
spectral characterization for compounds 2-18. This material is
a Ki values are the means of three experiments, each including six values
( SEM. b Ki values are the means of two experiments, each including six
values. a NA ) no activity.
References
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TLC from CHCl3/MeOH 9:1 showed no starting materials but two
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