G Model
CCLET-2896; No. of Pages 4
Z.-G. Luo et al. / Chinese Chemical Letters xxx (2014) xxx–xxx
3
Table 1
near 7 or 8 ppm for the methylene proton of the 1,3-diketo moiety
and 13C NMR absorptions for the methylene carbon of the 1,3-
diketo moiety near 97 ppm, respectively. In the negative ion MS
(ESI) spectrum, the loss of hydrogen ion substances [MꢀH]ꢀ were
usually observed as the base peak ion for all target compounds.
Selected characterization data of the targeted compounds are
listed below.
Inhibition of HIV-1 integrase strand transfer catalytic activities.a
Compound
R1
R2
IC50 (m
mol/L)b
c
4a
t-Bu
t-Bu
t-Bu
t-Bu
H
H
–
c
4b
Cl
F
–
c
4c
–
c
4d
CH3
H
–
4e
7.4
8.8
4a: White solid, yield: 41%; mp: 155–158 8C; 1H NMR
4f
H
Cl
F
(400 MHz, CDCl3):
d 0.96 (s, 18H, C(CH3)3), 1.33 (s, 18H,
4g
H
6.1
C(CH3)3), 2.44 (s, 6H, CH3), 3.42 (d, 4H, J = 13.2 Hz, ArCH2Ar),
4.45 (d, 4H, J = 13.2 Hz, ArCH2Ar), 4.75 (s, 4H, ArOCH2), 5.56 (s, 4H,
ArCH2), 6.85 (s, 2H, COCH), 6.90 (s, 4H, ArH), 7.12 (s, 4H, ArH), 7.18–
7.21 (m, 4H, ArH), 7.30–7.36 (m, 6H, ArH), 7.78 (s, 2H, ArOH), 15.31
4h
H
CH3
10.9
Baicalein
1.06
a
HIV-1 IN inhibitory activities were measured according to the procedure
described [27].
b
(s, 2H, OH); 13C NMR (100 MHz, CDCl3):
d 187.7, 181.5, 150.8,
Inhibition of strand transfer with the initial concentration at 25
mmol/L.
c
–: indicates that the HIV-IN inhibitory effect was less than 50% at the initial
149.8, 147.3, 141.3, 141.1, 136.4, 134.3, 132.5, 129.0, 128.3, 127.4,
127.1, 125.7, 125.0, 96.7, 75.7, 51.6, 33.9, 33.8, 31.8, 31.6, 30.9,
9.36; MS(ESI): m/z 1157.8 [MꢀH]ꢀ.
concentration.
4g: White solid, yield: 35%; mp: 170–172 8C; 1H NMR (400 MHz,
CDCl3): 2.43 (s, 6H, CH3), 3.45 (d, 4H, J = 13.2 Hz, ArCH2Ar), 4.54 (d,
4b: White solid, yield: 52%; mp: 182–185 8C; 1H NMR
d
(400 MHz, CDCl3):
d 0.93 (s, 18H, C(CH3)3), 1.31 (s, 18H,
4H, J = 13.2 Hz, ArCH2Ar), 4.77 (s, 4H, ArOCH2), 5.50 (s, 4H, ArCH2),
6.91 (s, 4H, ArH), 7.10–7.16 (m, 8H, ArH), 7.30–7.37 (m, 4H, ArH),
8.09 (s, 2H, COCH), 8.13 (s, 2H, ArOH), 15.15 (s, 2H, OH); 13C NMR
C(CH3)3), 2.45 (s, 6H, CH3), 3.49 (d, 4H, J = 13.2 Hz, ArCH2Ar),
4.50 (d, 4H, J = 13.2 Hz, ArCH2Ar), 4.75 (s, 4H, ArOCH2), 5.52 (s, 4H,
ArCH2), 6.68–6.73 (m, 4H, ArH), 6.83 (s, 2H, COCH), 7.01 (d, 4H,
J = 7.6 Hz, ArH), 7.12–7.17 (m, 8H, ArH), 7.36 (d, 4H, J = 8.4 Hz, ArH),
(100 MHz, CDCl3):
d 187.9, 181.3, 152.8, 149.8, 141.2, 136.3, 134.4,
7.80 (s, 2H, ArOH), 15.30 (s, 2H, OH); 13C NMR (100 MHz, CDCl3):
d
132.5, 132.4, 129.2, 128.5, 127.3, 125.7, 125.0, 119.3, 119.0, 96.8,
75.6, 50.9, 31.6, 9.31; MS (ESI): m/z 970.1 [MꢀH]ꢀ.
187.6, 181.6, 150.7, 151.3, 151.0, 147.1, 136.4, 134.5, 133.2, 132.7,
129.3, 128.6, 127.6, 125.8, 119.0, 118.7, 97.0, 75.7, 51.0, 34.0, 33.8,
31.8, 31.5, 30.9, 9.30; MS (ESI): m/z 1225.6 [MꢀH]ꢀ.
4h: White solid, yield: 33%; mp: 149–151 8C; 1H NMR
(400 MHz, CDCl3):
d 2.32 (s, 6H, CH3), 2.39 (s, 6H, CH3), 3.46 (d,
4c: White solid, yield: 46%; mp: 189–192 8C; 1H NMR
4H, J = 13.2 Hz, ArCH2Ar), 4.48 (d, 4H, J = 13.2 Hz, ArCH2Ar), 4.72 (s,
4H, ArOCH2), 5.48 (s, 4H, ArCH2), 6.65 (t, 4H, J = 7.6 Hz, ArH), 6.95
(d, 4H, J = 7.6 Hz, ArH), 7.05–7.09 (m, 8H, ArH), 7.13 (d, 4H,
J = 7.6 Hz, ArH), 7.97 (s, 2H, COCH), 8.06 (s, 2H, ArOH), 15.16 (s, 2H,
(400 MHz, CDCl3):
d 0.95 (s, 18H, C(CH3)3), 1.32 (s, 18H,
C(CH3)3), 2.44 (s, 6H, CH3), 3.43 (d, 4H, J = 13.2 Hz, ArCH2Ar),
4.42 (d, 4H, J = 13.2 Hz, ArCH2Ar), 4.75 (s, 4H, ArOCH2), 5.52 (s, 4H,
ArCH2), 6.85 (s, 2H, COCH), 6.90 (s, 4H, ArH), 7.10–7.16 (m, 8H,
ArH), 7.30–7.37 (m, 4H, ArH), 7.85 (s, 2H, ArOH), 15.33 (s, 2H, OH);
OH); 13C NMR (100 MHz, CDCl3):
d 187.2, 181.9, 153.7, 152.1,
141.1, 138.2, 136.4, 133.2, 131.3, 129.7, 129.3, 128.5, 127.7, 127.2,
125.7, 118.7, 96.9, 75.7, 51.5, 31.5, 21.1, 9.36; MS (ESI): m/z 961.4
[MꢀH]ꢀ.
13C NMR (100 MHz, CDCl3):
d 187.9, 181.3, 150.8, 149.8, 147.2,
141.4, 141.0, 136.3, 134.4, 132.7, 132.4, 129.2, 128.5, 127.3, 125.7,
125.0, 96.8, 75.6, 50.9, 34.0, 33.8, 31.8, 31.6, 30.9, 9.37; MS (ESI):
m/z 1193.6 [MꢀH]ꢀ.
The inhibition effects of the calix[4]arene derivative 4a–h were
measured by the HIV-1 integrase strand transfer activity assay,
which was carried out as described previously [27] with some
minor modifications. Compounds diluted in DMSO were pre-
incubated with 800 ng integrase at 37.8 8C in the reaction buffer in
the absence of Mn2+ for 10 min. Subsequently, 1.5 pmol donor DNA
and 9 pmol target DNA were added, and the reaction was initiated
by the addition of 10 mmol/L Mn2+ into the final reaction volume.
The reactions were carried out at 37.8 8C for 1 h, and a subsequent
detection procedure was applied to detect the assay signals. An
integrase inhibitor, baicalein, was used as the control compound
(positive control), whereas no compound but only DMSO in the
reaction mixture was set as the drug-free control (negative
control). The inhibition effects of compounds 4a-h were calculated
based on the positive and negative controls, and the data are
summarized in Table 1.
4d: White solid, yield: 43%; mp: 145–147 8C; 1H NMR
(400 MHz, CDCl3):
d 0.96 (s, 18H, C(CH3)3), 1.31 (s, 18H,
C(CH3)3), 2.33 (s, 6H, CH3), 2.43 (s, 6H, CH3), 3.42 (d, 4H,
J = 13.2 Hz, ArCH2Ar), 4.44 (d, 4H, J = 13.2 Hz, ArCH2Ar), 4.76 (s,
4H, ArOCH2), 5.52 (s, 4H, ArCH2), 6.86 (s, 2H, COCH), 6.92 (s, 4H,
ArH), 7.11–7.17 (m, 7H, ArH), 7.29–7.37 (m, 4H, ArH), 7.85 (s, 2H,
ArOH), 15.33 (s, 2H, OH); 13C NMR (100 MHz, CDCl3):
d 187.6,
181.1, 150.8, 149.7, 147.2, 141.2, 141.0, 136.2, 134.3, 132.7, 132.3,
129.1, 128.2, 127.3, 125.5, 125.0, 97.0, 75.2, 50.9, 34.1, 33.7, 31.5,
31.4, 30.9, 21.1, 9.35; MS (ESI): m/z 1185.3 [MꢀH]ꢀ.
4e: White solid, yield: 38%; mp: 177–180 8C; 1H NMR
(400 MHz, CDCl3):
d 2.43 (s, 6H, CH3), 3.45 (d, 4H, J = 13.2 Hz,
ArCH2Ar), 4.50 (d, 4H, J = 13.2 Hz, ArCH2Ar), 4.76 (s, 4H, ArOCH2),
5.52 (s, 4H, ArCH2), 6.70 (t, 4H, J = 7.2 Hz, ArH), 7.00 (d, 4H,
J = 7.6 Hz, ArH), 7.12 (d, 4H, J = 7.6 Hz, ArH), 7.19 (d, 4H, J = 7.6 Hz,
ArH), 7.34–7.40 (m, 6H, ArH), 8.02 (s, 2H, COCH), 8.10 (s, 2H, ArOH),
As shown in Table 1, p-tert-butylcalix[4]arene derivatives 4a–d
proved to be inactive in the ST assay at the concentration of
15.20 (s, 2H, OH); 13C NMR (100 Hz, CDCl3):
d 187.4, 181.8, 153.8,
25
activity in the low micromolar range (6.1–10.9
potent derivative was compound 4g, which had an IC50 value for
strand transfer of 6.1 mol/L. Moreover, the anti-IN activity of the
m
mol/L. The calix[4]arene derivatives 4e–h presented anti-IN
m
mol/L). The most
152.1, 141.5, 136.6, 134.7, 133.6, 129.6, 129.0, 128.5, 128.3, 127.7,
127.3, 126.0, 119.0, 96.9, 75.6, 51.6, 31.6, 9.31; MS (ESI): m/z 933.4
[MꢀH]ꢀ.
m
4f: White solid, yield: 36%; mp: 147–149 8C; 1H NMR (400 MHz,
compounds 4e–h with electron withdrawing groups or electron
donating groups on the benzene rings of the 1,3-diketo subunits in
alternate positions at the lower rim shows no clear difference. This
experimental observation seems to indicate that the bulky tert-
butyl groups reduced combination ability with integrase compa-
rable to H atoms at the upper rim of calix[4]arene. In addition, an
appropriate water-soluble anionic group incorporated at the upper
rim, including sulfonates, carboxylates, or phosphonates, seems
essential to enhance potential anti-integrase activity [13].
CDCl3):
d 2.44 (s, 6H, CH3), 3.49 (d, 4H, J = 13.2 Hz, ArCH2Ar), 4.50
(d, 4H, J = 13.2 Hz, ArCH2Ar), 4.75 (s, 4H, ArOCH2), 5.52 (s, 4H,
ArCH2), 6.68–6.73 (m, 4H, ArH), 7.01 (d, 4H, J = 7.6 Hz, ArH), 7.12–
7.17 (m, 8H, ArH), 7.36 (d, 4H, J = 8.4 Hz, ArH), 8.11 (s, 2H, COCH),
8.15 (s, 2H, ArOH), 15.19 (s, 2H, OH); 13C NMR (100 MHz, CDCl3):
d
187.6, 181.6, 153.7, 153.3, 151.9, 141.1, 136.4, 134.5, 133.2, 132.7,
129.3, 128.6, 127.6, 125.8, 119.0, 118.7, 97.0, 75.7, 51.0, 31.5, 9.30;
MS (ESI): m/z 1001.3 [MꢀH]ꢀ.
Please cite this article in press as: Z.-G. Luo, et al., Synthesis and anti-integrase evaluation of novel calix[4]arene derivatives containing