3-Aminoisoquinolines Targeting PDE4B
7.27 (s, 1H), 7.33 (s, 1H), 7.36 (s, 4H), 7.85 (d, J 8.71,
2H), 8.31 (s, 1H), 9.96 (s, 1H). Calc. FW for C26H24ClN3O3
461.15, found in MS: 463 (9) M+, 461 (40) M+, 202 (70).
(3). This assay was provided for selected compounds by
DTP NCI program (3). Sixteen different protein kinases
were tested for their inhibition by 2g and 4d. Screening
was performed by the National Centre for Protein Kinase
Profiling, Division of Signal Transduction Therapy, Univer-
sity of Dundee. The data are portrayed as mean % activity
and standard deviation of assay duplicates (9).
1
m.p. 187 °C; 4b: H-NMR: 2.79 (s, 3H), 3.91 (s, 3H), 3.92
(s, 3H), 4.37 (d, J 5.30, 2H), 6.61 (d, J 8.62, 2H), 6.96 (t,
J 5.30, 1H), 7.17 (m, 2H), 7.27 (s, 1H), 7.34 (s, 1H), 7.39
(m, 2H), 7.86 (d, J 8.62, 2H), 8.30 (s, 1H), 9.97 (s, 1H).
Calc. FW for C26H24FN3O3 445.18, found in MS: 445 (70)
M+, 228 (100). m.p. 240 °C; 4c: 1H-NMR: 2.24 (s, 3H),
2.80 (s, 3H), 3.70 (s, 3H), 3.92 (s, 6H), 4.07 (s, 2H), 6.43
(s, 1H), 6,66 (d, J 8.70 2H), 7.27 (s, 1H), 7.33 (s, 1H),
7.34 (s, 1H), 7.88 (d, J 8.70, 2H), 8.31 (s, 1H), 9.96
(s, 1H). Calc. FW for C25H27N5O3 445.18, found in MS:
445 (15) M+, 228 (35). m.p. 132 °C; 4d: 1H-NMR: 1.28 (t,
J 7.21, 3H,), 2.25 (s, 3H), 2.80 (s, 3H), 3.92 (s, 3H), 3.93
(s, 3H), 4.04 (q, J 7.21, 2H), 4.07 (d, J 5.11, 2H,), 6.42 (t,
J 5.11, 1H,), 6.66 (d, J 8.79, 2H), 7.27 (s, 1H), 7.34 (s,
1H), 7.36 (s, 1H), 7.88 (d, J 5.11, 2H), 8.32 (s, 1H), 9.96
(s, 1H). Calc. FW for C26H29N5O3 459.2, found in MS: 459
Three-dimensional floating cell culture
Cells were seeded in a 96-well plate with an ultra-low
attachment surface and round bottom (Product Number
7007; Corning Inc., Corning, NY, USA). The area of the
spheroid was measured using a IN Cell Analyzer 1000 (GE
Healthcare Bio-Sciences, Pittsburgh, PA, USA) according
to manufactures’ protocol.
Cell culture
1
(10) M+, 242 (25), 228 (25), 109 (10); m.p. 193 °C; 4e: H-
Human colorectal cancer cell lines HKe3-wtKRAS and
NMR: 1.32 (t, J 3.82, 3H), 2.81 (s, 3H), 3.92 (s, 6H), 4.12
(m, 4H), 6.57 (s, 1H), 6.68 (d, J 8.20 2H), 7.28 (s, 1H),
7.34 (s, 1H), 7.41 (s, 1H), 7.67 (s, 1H) 7.84 (d, J 8.20,
2H), 8.32 (s, 1H), 9.97 (s, 1H). Calc. FW for C25H27N5O3
445.18, found in MS: 445 (40) M+, 228 (75). m.p. 145 °C;
4f: 1H-NMR: 2.80 (s, 3H), 3.92 (s, 3H), 3.93 (s, 3H), 4.42
(d, J 6.10, 2H), 6.60 (d, J 8.56, 2H), 7.03 (t, J 6.10, 1H),
7.27 (s, 1H), 7.33 (s, 1H), 7.35 (d, J 5.11, 2H) 7.88 (d, J
8.56, 2H), 8.32 (s, 1H), 8.51 (d, J 5.11, 2H), 9.96 (s, 1H).
Calc. FW for C25H24N3O3 428.18, found in MS: 428 (80)
M+, 257 (30), 211 (100), 153 (25). m.p. 148–150 °C; 4g:
1H-NMR: 1.32 (t, J 7.26, 3H,) 2.82 (s, 3H), 3.93 (s, 3H),
3.9 (s, 3H), 4.07 (q, J 7.23, 2H), 4.36 (d, J 5.70, 2H), 5.70
(t, J 5.70, 1H), 7.28 (dd, J 8.90, J 2.02, 1H), 7.32 (s, 1H),
7.36 (s, 1H), 7.37 (d, J 8.90, 1H), 7.43 (s, 1H), 7.47 (d, J
2.02, 1H), 7.67 (s, 1H), 8.33 (s, 1H), 10.51 (s, 1H). Calc.
FW for C25H26ClN5O3 479.2, found in MS: 479 (25) M+,
481 (8) M+, 109 (100), 81 (30). m.p. 98–9 °C; 4h: 1H-
NMR: 2.83 (s, 3H), 3.93 (s, 3H), 3.94 (s, 3H), 4.53 (d, J
6.21, 2H), 5.37 (t, J 6.21, 1H), 7.15 (m, 2H), 7.25 (m, 1H),
7.31 (s, 1H), 7.36 (s, 1H), 7.38 (m, 2H), 7.42 (m, 2H), 8.34
(s, 1H), 10.57 (s, 1H). Calc. FW for C26H23ClFN3O3
479.14, found in MS: 479 (20) M+, 245 (40), 182 (100),
154 (50). m.p. 230 °C; 6: 1H-NMR: 1.25 (t, J 6, 3H), 2.25
(s, 3H), 4.04 (q, J 6, 2H), 4.08 (d, J 4.8, 2H), 6.45 (t, J
4.8, 1H), 6.71 (d, J 9, 2H), 7.36 (s,1H), 7.39 (t, J 7.2, 1H),
7.47 (t, J 7.3, 1H), 7.82 (m, 6H), 8.41 (s, 1H), 9.75 (s, 1H).
Calc. FW for C24H24N4O 384.2, found in MS: 384 (5) M+,
290 (25), 262 (95), 242 (20); m.p. 135–7 °C; 7: 1H-NMR:
2.17 (s, 3H), 2.35 (m, 8H), 3.53 (s, 2H), 7.45 (m, 4H), 7.85
(m, 4H), 7.96 (d, J 7, 2H), 8.45 (s, 1H), 10.40 (s, 1H).Calc.
FW for C23H25N3O 359.2, found in MS: 359 (100) M+, 288
(95); m.p. 152–4 °C.
HKe3-mtKRAS were maintained as previously described
(6).
In silico study
com (4, 5). AutoDock Tools and Vina were used for rever-
sal docking in agreement with author’s guidelines (10). File
3IAK.pdb with co-ordinates of papaverine and PDE4D was
used for calculation of binding poses of 2-4. The catalytic
domain is the most conserved domain among the PDE
families. PDE4B and PDE4D have most similar active site
among family of PDE4 isoenzymes (11). Vina scoring func-
tion was calculated as -8.8 kcal/mol for 2g and -8.3 kcal/
mol for 4d. Analysis of binding poses of 2g in PDE4D was
discussed below. Discovery Studio 3.05 (DS 3.05, Accel-
rys) was used for visualization of docking results as free
software from Accelrys in agreement with company guide-
lines.
Results and Discussion
Earlier, it was found that aryl amide of 1–2a (Figure 1) with
para-substituents possessed weak cytostatic activity on
CaOv cell line (8). Later, raised methods of virtual screen-
ing among drug target like PASS-online helped us to
understand several main classes of possible targets for
this chemotype (12, 13).
Isoquinoline 1 was synthesized according to the previously
described procedure (8). Primary library of compounds 2
and 3 was generated from simplest rules of medicinal
chemistry as such amides 2 with meta- and para-electron
donor or acceptor substituents. Aryl amides (2) and
thiourea or urea (3) were synthesized according to the
Scheme 2. The 3-amino group of 1 is less nucleophilic
than such group at other position of isoquinoline (1) as we
Biology
MTT assay with selected cancer cell lines were accom-
plished in agreement with well-documented procedures
Chem Biol Drug Des 2016; 87: 575–582
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