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S1
Supporting Information
Ligand-free Pd-catalysed decarboxylative arylation of Imidazo[1,2-a]pyridine-3-carboxylic acids with Aryl bromides†
Uttam B. Karalea,b, Saradhi Kalaria, Jala Shivakumarc, Vitthal B. Makanea,b, Dattatraya A. Babara,b, Ritesh P. Thakared, Bathini Nagendra Babuc, Sidharth Choprad, Haridas B. Rodea,b*
a Department of Natural Product Chemistry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad-500007, India
bAcademy of Scientific and Innovative Research (AcSIR), New Delhi, IndiacDepartment of Medicinal Chemistry, National Institute of Pharmaceutical Education and
Research, Balanagar, Hyderabad - 500 037, IndiadMicobiology Division, Central Drug Research Institute, Lucknow - 226 031, India
CORRESPONDING AUTHOR’S E-MAIL [email protected]
Electronic Supplementary Material (ESI) for RSC Advances.This journal is © The Royal Society of Chemistry 2016
S2
Table of Contents
Materials and Methods S3
Bromides used in the study S4
Chlorides used in the study S5
Synthesis of starting materials S61H and 13C NMR spectra of the compounds S10
Antibacterial assay S68
References S68
S3
Materials and Methods1H and 13C NMR spectra were recorded on a Bruker Avance 300 or 400 or 500 spectrometer
and are referred to the residual solvent signal: dimethylsulfoxide-d6(2.50) for 1H and (39.52)
for 13C; CDCl3: (7.26) for 1H and (77.16) for 13C. Chemical shifts (δ) are given in ppm and
coupling constants (J) were measured in Hz. The following abbreviations are used; s-singlet,
d-doublet, dd-doublet of doublet, t-triplet, td-triplet of doublet, dt-doublet of triplet, q-
quartet, qd-quartet of doublet, qn-quintet, br-broad. ESI- and HR ESI-MS were recorded
using Finnigan MAT 1020B and Thermo Scientific Q Exactive hybrid quadrupole-Orbitrap
mass; values are given in m/z. Column chromatography was carried out using silica gel (60–
120 mesh) packed in glass columns. Analytical TLC was carried out on Macherey-Nagel 60
F245aluminium-backed silica gel plates. Melting point of compound was measured on Stuart
melting point apparatus SMP3. Anhydrous solvents and chemical materials were purchased
from commercial sources.
S4
Bromides used in the study
Br Br2b
Br
O
Br
O
Br
N
BrH
O
O
Br
NO2
Br
CF3
BrBr
2d 2e
2h
Br
OO
2i 2j
2l
2k
Br
O
Br2m 2n
2q
2o 2pBr
F
CN
Br
F
F
O
O
OH
2g
2fBr2c
O
Br
CN
2a
Br
S
Br
N
2r
2y2x
Br
N
Br
N
N
2v
2t2s
Br
O
O
O
N
Br Br
NHHN
2u
2w
Br
S5
Chlorides used in the study
Cl Br
Cl
O
Cl
NO2
Cl
CF3
ClCl
2d' 2h'
2i' 2j'
Cl
O
2n'
OH
2g'Cl2c'
Cl
CN
2a' 2b'
2m'
S6
Synthesis of starting materials
N
NH2R1
R2
R3R4
R1 R2 R3 R4
CH3
CH3
CH3
Cl
N
N
OO
R3
R1R2
R41. DMF acetal, 50 °C
2. ethyl 2-bromoacetate,NaHCO3, DMF,50 °C
No.
1b1/1b2/1b
N
N
OHO
R3
R1R2
R4LiOH, H2O/EtOH,reflux
ester synthesisreaction time (h)
stage1
stage2
ester hydrolysisreaction time (h)
1c1/1c2/1c
1d1/1d2/1d
1f1/1f2/1f
1b1, 1c1,1d1, 1f1
1b2, 1c2,1d2, 1f2
1b, 1c,1d, 1f
4 12
24 12
12
12
7 15 24
8 12 72
H H
H H H
H H H
H
H H H
N
NH2R1
R2
R3
R1 R2 R3
CH3
CF3
N
N
OO
R3
R1R2
ethyl 2-chloroacetoacetate,DME, reflux 3 days
No.
1e1/1e2/1e
N
N
OHO
R3
R1R2
LiOH, H2O/EtOH,reflux
esterhydrolysis
r eactionti me(h)
1g1/1g2/1g
1h1/1h2/1h
1e1, 1g1, 1h1 1e2, 1g2, 1h2 1e, 1g, 1h
Cl
24
48
36
H H
H H
H H
Imidazo[1,2-a]pyridine-3-carboxylic acids 1b-1h were synthesized using reporting procedure or modification thereof.1 Below is the brief description of their preparation and analysis.
S7
Synthesis of 1b, 1c, 1d, 1f
6-methylimidazo[1,2-a]pyridine-3-carboxylic acid (1b)
5-Methylpyridin-2-amine 1b1 (5g, 46.23 mmol) and N,N-dimethyl formamide dimethyl acetal (30 mL) were stirred at 50 °C for 4 hrs. Upon completion, reaction mixture was evaporated on rotary evaporator and dried. The dried residue, ethyl 2-bromoacetate (11.50 g, 69.29 mmol) and NaHCO3 (5.8 gm, 69.04 mmol) in DMF (30 mL) were stirred at 50 °C. The progress of reaction was monitored by TLC. After 15 hrs the reaction mixture was added in water (200 mL) and extracted with ethyl acetate (2x150 mL). The combined organic phase was separated, washed with water (100 mL), brine (100 mL) and dried with sodium sulphate. The organic solvent was evaporated on rotary evaporator and crude material obtained was purified using silica gel column chromatography with 20% ethyl acetate in hexane. 1b2 was obtained as green liquid (5g, 53% yield). 1H NMR (400 MHz, CDCl3): δ 9.11 (S, 1H), 8.25 (s, 1H), 7.66 (d, J = 9.1 Hz, 1H), 7.27 (dd, J = 9.1, 1.7 Hz, 1H), 4.41 (q, J = 7.1 Hz, 2H), 2.41 (s, 3H), 1.42 (t, J = 7.1 Hz, 3H); 13C NMR (100 MHz, CDCl3): δ 160.6, 147.1, 140.8, 130.5, 125.4, 124.2, 116.8, 115.4, 60.3, 18.3, 14.4; HRMS (ESI-MS):Calc. for C11H13N2O2 [(M+H)+]: 205.0972, Found: 205.0976.
1b2(2g, 9.8 mmol) was dissolved in ethanol (24 mL) and 20 mL of LiOH (1 N aq. solution, 19.6 mmol) was added drop wise. The resulting reaction mixture was refluxed for 12 hrs. Ethanol was then removed on rotary evaporator and resulting mixture was cooled at ice bath temperature. The 4N HCl was added drop wise till the PH of reaction mixture became ≈ 4. The precipitated solid was filtered off and dried to furnish 1b2 as white solid (1.2 gm, 91 % yield). mp= 188-190°C; 1H NMR (400 MHz, DMSO-d6): δ 9.07 (s, 1H), 8.18 (s, 1H), 7.68 (d, J = 9.1 Hz, 1H), 7.40 (dd, J = 9.1, 1.7 Hz, 1H), 2.37 (s, 3H); 13C NMR (100 MHz, DMSO-d6): δ 161.4, 146.8, 140.8, 130.7, 125.0, 124.1, 116.8, 115.6, 17.9; HRMS (ESI-MS):Calc. for C9H9N2O2 [(M+H)+]: 177.0659, Found: 177.0667.
In an analogous way 1c, 1d, 1f were synthesized.
1c22: Obtained 6.19 g (65%) 1c2 as white solid from 5.0g of 1c1. mp= 72-74°C; 1H NMR (400 MHz, CDCl3): δ 9.15-9.09 (m, 1H), 8.24-8.17 (m, 1H), 7.46 (s, 1H), 6.84 (d, J = 6.8 Hz, 1H), 4.42-4.33 (m, 2H), 2.43 (s, 3H), 1.40-1.32 (m, 3H); 13C NMR (125 MHz, CDCl3): δ 160.6, 148.8, 141.4, 138.7, 126.6, 116.6, 116.3, 115.3, 60.2, 21.3, 14.4; HRMS (ESI-MS):Calc. for C11H13N2O2 [(M+H)+]: 205.09715, Found: 205.09837.
1c2: Obtained 0.64 g (74%) 1c as white solid from 1.0g of 1c2. mp= 189-192°C; 1H NMR (400 MHz, DMSO-d6): δ 9.16 (d, J = 7.0 Hz, 1H), 8.13 (s, 1H), 7.55 (s, 1H), 7.04 (dd, J = 7.0, 1.5 Hz, 1H), 2.42 (s, 3H); 13C NMR (125 MHz, DMSO-d6): δ 161.4, 148.1, 140.9, 138.6, 126.6, 116.8, 115.9, 115.6, 20.7; HRMS (ESI-MS):Calc. for C9H9N2O2 [(M+H)+]: 177.0659, Found: 177.0667.
1d2: Obtained 3.25 g (34%) 1d2 as red solid from 5.0g of 1d1. mp= 72-74°C;1H NMR (400 MHz, CDCl3) δ 9.13 (d, J = 7.0 Hz, 1H), 8.25 (s, 1H), 7.19-7.15 (m, 1H), 6.91 (t, J = 7.0 Hz, 1H), 4.38 (q, J = 7.1 Hz, 2H), 2.63 (s, 3H), 1.39 (t, J = 7.1 Hz, 3H); 13C NMR (125 MHz,
S8
CDCl3): δ 160.8, 148.7, 140.8, 127.7, 126.5, 125.5, 116.3, 114.3, 60.5, 17.0, 14.6; HRMS (ESI-MS):Calc. for C11H13N2O2 [(M+H)+]: 205.0972, Found: 205.0977.
1d: Obtained 0.65 g (49%) 1d as violet solid from 1.5 g of 1d2. mp= 184-185°C; 1H NMR (400 MHz, DMSO-d6): δ 9.20 (d, J = 7.0 Hz, 1H), 8.44 (s, 1H), 7.54 (d, J = 7.1 Hz, 1H), 7.27 (t, J = 7.0 Hz, 1H), 2.59 (s, 3H); 13C NMR (75 MHz, DMSO-d6): δ 160.8, 144.9, 135.5, 129.9, 125.8, 125.5, 117.0, 116.4, 16.5; HRMS (ESI-MS):Calc. for C9H9N2O2 [(M+H)+]: 177.06585, Found: 177.06720.
1f21c: Obtained 5.5 g (63%) 1f2 as yellow semisolid from 5.0g of 1f1. 1H NMR (400 MHz, CDCl3) δ 9.39 (dd, J = 2.0, 0.8 Hz, 1H), 8.29 (s, 1H), 7.68 (dd, J = 9.5, 0.8 Hz, 1H), 7.39 (dd, J = 9.5, 2.0 Hz, 1H), 4.43 (q, J = 7.1 Hz, 2H), 1.42 (t, J = 7.1 Hz, 3H); 13C NMR (125 MHz, CDCl3): δ 160.5, 146.8, 141.9, 129.0, 125.9, 122.9, 118.2, 116.4, 60.9, 14.6; HRMS (ESI-MS):Calc. for C10H10ClN2O2 [(M+H)+]: 225.0425, Found: 225.0428.
1f1c: Obtained 0.72 g (54%) 1f as violet solid from 1.5 g of 1f2. mp= 206°C; 1H NMR (400 MHz, DMSO-d6): δ 9.31 (dd, J = 2.0, 0.6 Hz, 1H), 8.27 (s, 1H), 7.84 (dd, J = 9.5, 0.6 Hz, 1H), 7.62 (dd, J = 9.5, 2.0 Hz, 1H); 13C NMR (100 MHz, DMSO-d6):160.1, 140.2, 127.4, 126.8, 124.0, 120.3, 117.8, 117.2; HRMS (ESI-MS):Calc. for C8H6ClN2O2 [(M+H)+]: 197.01123, Found: 197.01253.
Synthesis of 1e, 1g, 1h
Ethyl-2-chloroacetoacetate (7.93 g, 45.8 mmol) and 2-Amino-4-picoline (10.0 g, 91.5 mmol)were dissolved in 95 mL of 1,2-dimethoxyethane (DME) and heated for 48 hrs at reflux. The reaction mixture was cooled and solid (2-amino-4-picoline hydrochloride salt) was collected and washed with hexane. The filtrate was concentrated in vacuo and resulting residue was dissolved in dichloromethane (200 mL) and washed with 5% acetic acid solution (2x 50 mL) and brine. The organic phase was dried with sodium sulfate, filtered and concentrated in vacuo. Crude product was purified by silica gel with 22% ethyl acetate in hexane to furnish 7.0 g (34%) of ethyl 2,7-dimethylimidazo[1,2-a]pyridine-3-carboxylate (1e2)1a as a yellowish solid. mp= 66°C;1H NMR (500 MHz, CDCl3): δ 9.12 (d, J = 7.1 Hz, 1H), 7.35 (s, 1H), 6.76 (dd, J = 7.1, 1.2 Hz, 1H), 4.38 (q, J = 7.1 Hz, 2H), 2.66 (s, 3H), 2.40 (s, 3H), 1.40 (t, J = 7.1 Hz, 3H); 13C NMR (125 MHz, CDCl3): δ 161.4, 152.6, 147.2, 139.1, 127.1, 116.1, 115.3, 112.1, 60.2, 21.3, 16.5, 14.5; HRMS (ESI-MS):Calc. for C12H15N2O2 [(M+H)+]: 219.11280, Found: 219.11397.
1e2 (4.0 g, 18.34 mmol) was dissolved in of 55 mL ethanol and 37 mL of 1 N LiOH solution (36.58 mmol) was added. The reaction mixture was refluxed for 48 hrs. Once complete, ethanol was removed on rotary evaporator and resulting mixture was cooled at ice bath temperature. The 4N HCl was added drop wise till the pH of reaction mixture became ≈ 4. The precipitated solid was filtered off and dried under vacuum to furnish 1e1a as white solid (2.6 gm, 78 % yield). mp= 216-218°C; 1H NMR (400 MHz, DMSO-d6): δ 9.33 (d, J = 7.1 Hz, 1H), 7.79 (s, 1H), 7.45 (dd, J = 7.1, 1.5 Hz, 1H), 2.71 (s, 3H), 2.55 (s, 3H); 13C NMR (75 MHz, DMSO-d6): δ 160.9, 146.4, 141.9, 140.0, 128.4, 120.1, 113.3, 110.8, 21.0, 12.3; HRMS (ESI-MS):Calc. for C10H11N2O2 [(M+H)+]: 191.08150, Found: 191.08264.
S9
In an analogous way 1g and 1h were synthesized.
1g21c: Obtained 4.0 g (43%) 1g2 as yellow solid from 10.0 g of 1g1. mp= 102-104°C;1H NMR (500 MHz, CDCl3): δ 9.40 (dd, J = 2.0, 0.7 Hz, 1H), 7.56 (d, J = 9.3 Hz, 1H), 7.35 (dd, J = 9.3, 2.0 Hz, 1H), 4.44 (q, J = 7.1 Hz, 2H), 2.71 (s, 3H), 1.44 (t, J = 7.1 Hz, 3H); 13C NMR (125 MHz, CDCl3): δ 161.3, 153.3, 145.2, 128.9, 126.1, 122.1, 117.0, 113.2, 60.7, 16.7, 14.6; HRMS (ESI-MS):Calc. for C11H12ClN2O2 [(M+H)+]: 239.05818, Found: 239.05941.
1g1c: Obtained 1.5g (68%) 1g as white solid from 1.0 g of 1g2. mp= 158-160°C; 1H NMR (400 MHz, DMSO-d6): δ 9.31 (dd, J = 2.1, 0.6 Hz, 1H), 7.71 (dd, J = 9.5, 0.6 Hz, 1H), 7.59 (dd, J = 9.5, 2.1 Hz, 1H), 2.59 (s, 3H); 13C NMR (75 MHz, DMSO-d6) δ 161.9, 151.7, 144.2, 128.7, 125.4, 120.8, 117.0, 113.1, 15.9; HRMS (ESI-MS):Calc. for C9H8ClN2O2 [(M+H)+]: 211.02688, Found: 211.02825.
1h2: Obtained 0.72 g (45%) 1h2 as yellow solid from 1.0 g of 1h1. mp= 88-90°C;1H NMR (500 MHz, CDCl3): δ 9.51 (d, J = 7.0 Hz, 1H), 7.70 (d, J = 7.1 Hz, 1H), 7.04 (t, J = 7.1 Hz, 1H), 4.45 (q, J = 7.1 Hz, 2H), 2.78 (s, 3H), 1.45 (t, J = 7.1 Hz, 3H), 13C NMR (100 MHz, DMSO-d6): δ 161.3, 153.7, 142.5, 131.1, 125.7, 125.6, 122.2 (q, J= 272.2 Hz), 113.5, 112.0, 60.8, 16.9, 14.4; HRMS (ESI-MS):Calc. for C12H12F3N2O2 [(M+H)+]: 273.08454, Found: 273.08563.
1h: Obtained 0.29 g (52%) 1h as pale yellow solid from 0.62 g of 1h2. mp= 171-173°C;1H NMR (400 MHz, DMSO-d6): δ 9.49 (d, J = 7.0 Hz, 1H), 7.94 (d, J = 7.3 Hz, 1H), 7.26 (t, J = 7.1 Hz, 1H), 2.65 (s, 3H); 13C NMR (75 MHz, DMSO-d6): δ 162.0, 152.1, 141.3, 131.7, 126.3 (X2), 119.2 (q, J= 272.1 Hz), 112.5, 16.1; HRMS (ESI-MS):Calc. for C10H8F3N2O2 [(M+H)+]: 245.05324, Found: 245.05448.
S10
1H and 13C NMR spectra of the compounds
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0f1 (ppm)
3.13
3.44
2.14
1.01
1.13
1.00
1.01
1.371.391.40
2.372.38
4.354.374.394.40
7.237.237.257.257.617.64
8.22
9.08
N
N
OO
1H NMR spectrum of 1b2
102030405060708090100110120130140150160f1 (ppm)
14.4
18.3
60.3
115.4
116.8
124.2
125.4
130.5
140.8
147.1
160.6
N
N
OO
13C NMR spectrum of 1b2
S11
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.22
1.06
1.03
0.97
1.00
2.37
7.397.397.417.41
7.677.69
8.18
9.07
N
N
OOH
1H NMR spectrum of 1b
2030405060708090100110120130140150160170180f1 (ppm)
17.9
115.6
116.8
124.1
125.0
130.7
140.8
146.8
161.4
N
N
OOH
13C NMR spectrum of 1b
S12
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.12
3.20
2.08
1.04
0.96
0.93
1.00
1.341.40
2.43
4.334.42
6.836.84
7.46
8.178.24
9.089.119.139.16
N
N
OO
1H NMR spectrum of 1c2
0102030405060708090100110120130140150160f1 (ppm)
14.4
21.3
60.2
115.3
116.3
116.6
126.6
138.7
141.4
148.8
160.6
N
N
OO
13C NMR spectrum of 1c2
S13
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0f1 (ppm)
3.27
1.06
0.96
0.90
1.00
2.42
7.037.05
7.55
8.13
9.159.17
N
N
OOH
1H NMR spectrum of 1c
0102030405060708090100110120130140150160170f1 (ppm)
20.7
115.6
115.9
116.8
126.6
138.6
140.9
148.1
161.4
N
N
OOH
13C NMR spectrum of 1c
S14
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.08
3.00
2.00
1.00
0.92
0.88
0.94
1.381.391.41
2.63
4.364.384.394.41
6.896.916.937.137.20
8.25
9.129.14
N
N
OO
1H NMR spectrum of 1d2
102030405060708090100110120130140150160170f1 (ppm)
14.6
17.0
60.5
114.3
116.3
125.5
126.5
127.7
140.8
148.7
160.8
N
N
OO
13C NMR spectrum of 1d2
S15
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.14
1.07
1.03
0.93
1.00
2.59
7.257.277.28
7.537.55
8.44
9.199.21
N
N
OOH
1H NMR spectrum of 1d
0102030405060708090100110120130140150160170f1 (ppm)
16.5
116.4
117.0
125.5
125.8
129.9
135.5
144.9
160.8
N
N
OOH
13C NMR spectrum of 1d
S16
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.5f1 (ppm)
4.34
2.44
1.19
1.27
1.08
1.00
1.42
4.404.424.444.45
7.377.387.407.407.677.69
8.29
9.399.399.399.39
10.69
N
N
OO
Cl
1H NMR spectrum of 1f2
0102030405060708090100110120130140150160170f1 (ppm)
14.6
60.9
116.4
118.2
122.9
125.9
129.0
141.9
146.8
160.5
N
N
OO
Cl
13C NMR spectrum of 1f2
S17
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
1.001.06
0.88
0.90
7.607.617.637.637.837.85
8.27
9.319.319.319.31
N
N
OOH
Cl
1H NMR spectrum of 1f
-100102030405060708090100110120130140150160170f1 (ppm)
117.2
117.8
120.3
124.0
126.8
127.4
140.2
160.1
N
N
OOH
Cl
13C NMR spectrum of 1f
S18
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.14
3.22
3.14
2.08
1.04
0.96
1.00
1.40
2.40
2.66
4.374.39
6.766.766.776.77
7.35
9.119.13
N
N
OO
1H NMR spectrum of 1e2
102030405060708090100110120130140150160f1 (ppm)
14.5
16.5
21.3
60.2
112.1
115.3
116.1
127.1
139.1
147.2
152.6
161.4
N
N
OO
13C NMR spectrum of 1e2
S19
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.173.00
1.07
1.03
1.06
2.552.71
7.437.447.457.46
7.79
9.329.34
N
N
OOH
1H NMR spectrum of 1e
0102030405060708090100110120130140150160170f1 (ppm)
12.3
21.0
110.8
113.3
120.1
128.4
140.0
141.9
146.4
160.9
N
N
OOH
13C NMR spectrum of 1e
S20
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.0f1 (ppm)
3.09
2.98
2.00
0.941.00
0.80
1.431.441.46
2.71
4.424.434.454.46
7.347.347.367.367.557.57
9.409.409.409.40
N
N
OO
Cl
1H NMR spectrum of 1g2
0102030405060708090100110120130140150160f1 (ppm)
14.6
16.7
60.7
113.2
117.0
122.1
126.1
128.9
145.2
153.3
161.3
N
N
OO
Cl
13C NMR spectrum of 1g2
S21
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.0f1 (ppm)
3.47
1.111.19
1.00
2.59
7.587.587.607.617.697.707.727.72
9.319.319.319.31
N
N
OOH
Cl
1H NMR spectrum of 1g
0102030405060708090100110120130140150160f1 (ppm)
15.9
113.1
117.0
120.8
125.4
128.7
144.2
151.7
161.9
N
N
OOH
Cl
13C NMR spectrum of 1g
S22
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.0f1 (ppm)
3.33
3.16
2.12
1.08
1.11
1.00
1.431.451.46
2.78
4.424.444.464.47
7.027.047.06
7.697.72
9.509.52
N
N
OO
F
F
F
1H NMR spectrum of 1h2
0102030405060708090100110120130140150160f1 (ppm)
14.4
16.9
60.8
112.0
113.5
118.6
124.0
125.7
131.1
142.5
153.7
161.3
N
N
OO
F
F
F
13C NMR spectrum of 1h2
S23
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.22
1.05
1.01
1.00
2.65
7.247.267.28
7.937.95
9.499.50
N
N
OOH
F
F
F
1H NMR spectrum of 1h
0102030405060708090100110120130140150160170f1 (ppm)
16.1
112.5
113.6
117.4
121.0
124.6
131.7
141.3
152.1
162.0
N
N
OOH
F
F
F
13C NMR spectrum of 1h
S24
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
1.05
1.12
3.113.00
1.02
6.916.91
7.257.31
7.687.747.78
8.368.38
N
N
N
1H NMR spectrum of 3a
0102030405060708090100110120130140150f1 (ppm)
111.4
113.6
118.6
123.3
125.4
133.2
134.1
134.3
147.2
N
N
N
13C NMR spectrum of 3a
S25
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
3.18
1.02
1.012.032.051.90
1.00
2.44
6.776.806.83
7.167.34
7.647.69
8.318.32
N
N
1H NMR spectrum of 3b
0102030405060708090100110120130140150f1 (ppm)
21.47
112.54
118.35
123.51
124.18
125.90
126.47
128.17
138.32
146.11
N
N
13C NMR spectrum of 3b
S26
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0f1 (ppm)
1.01
1.01
1.024.021.070.94
1.00
6.77
7.16
7.387.487.52
7.67
8.298.31
N
N
1H NMR spectrum of 3c
05101520253035404550556065707580859095105115125135145f1 (ppm)
112.5
118.1
123.3
125.6
128.1
132.4
146.0
N
N
13C NMR spectrum of 3c
S27
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
3.14
1.00
2.011.00
2.000.881.00
0.94
3.88
7.037.087.157.20
7.457.507.637.658.248.248.25
8.26
N
N
O
1H NMR spectrum of 3d
0102030405060708090100110120130140150160f1 (ppm)
55.55
112.52
114.84
118.30
121.68
124.10
129.82
132.08
145.90
159.77
N
N
O
13C NMR spectrum of 3d
S28
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
6.00
1.132.11
1.04
2.010.981.02
1.00
3.03
6.746.756.766.766.776.776.816.87
7.12
7.38
7.607.637.658.268.278.28
N
N
N
1H NMR spectrum of 3e
404550556065707580859095105115125135145155f1 (ppm)
40.5
112.3
112.8
116.7
118.1
123.6
123.8
126.3
129.4
131.4
145.6
150.5
N
N
N
13C NMR spectrum of 3e
S29
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
3.13
1.010.980.982.03
1.03
1.030.90
1.00
3.87
6.826.936.997.077.097.117.147.23
7.44
7.667.697.70
8.368.38
N
N
O
1H NMR spectrum of 3f
0102030405060708090100110120130140150160f1 (ppm)
55.5
112.7
113.7
113.9
118.4
123.7
130.5
130.7
132.7
146.3
160.4
N
N
O
13C NMR spectrum of 3f
S30
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
1.05
1.17
1.991.051.001.002.13
1.061.06
1.03
6.85
7.24
7.517.647.747.81
8.018.428.43
N
N
1H NMR spectrum of 3g
05101520253035404550556065707580859095105115125135145f1 (ppm)
113.0
118.3
123.5
126.6
126.9
132.5
133.0
133.7
146.1
N
N
13C NMR spectrum of 3g
S31
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0f1 (ppm)
1.00
1.07
1.062.181.911.020.930.972.10
6.676.686.707.197.237.397.437.507.567.69
7.79
N
N
1H NMR spectrum of 3h
0102030405060708090100110120130140150f1 (ppm)
112.3
118.1
123.7
124.4
125.7
126.4
128.8
129.7
133.8
145.9
N
N
13C NMR spectrum of 3h
S32
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
1.00
3.68
3.042.95
1.00
6.866.886.90
7.217.29
7.677.737.76
8.358.37
N
N
F
FF
1H NMR spectrum of 3i
0102030405060708090100110120130140150f1 (ppm)
113.14
118.68
123.02
123.28
124.48
124.97
126.42
127.97
146.85
147.42
N
N
F
FF
13C NMR spectrum of 3i
S33
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
3.14
0.99
1.32
3.081.03
2.01
1.00
2.66
6.866.886.897.217.28
7.65
8.09
8.408.41
N
N
O
1H NMR spectrum of 3j
0102030405060708090100110120130140150160170180190200f1 (ppm)
26.6
113.1
118.4
123.4
129.3
133.7
133.9
136.1
146.8
197.1
N
N
O
13C NMR spectrum of 3j
S34
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
3.03
0.99
2.83
2.051.020.91
1.96
1.00
3.97
6.88
7.227.29
7.647.68
7.808.15
8.398.41
N
N
OO
1H NMR spectrum of 3k
-100102030405060708090100110120130140150160170f1 (ppm)
52.4
113.2
118.6
123.5
125.0
127.4
129.4
130.7
146.7
166.7
N
N
OO
13C NMR spectrum of 3k
S35
2.63.03.43.84.24.65.05.45.86.26.67.07.47.88.2f1 (ppm)
3.23
1.06
1.09
1.031.100.961.132.07
1.00
3.56
6.746.776.80
7.207.24
7.487.577.627.668.098.108.118.11
N
N
O
O
1H NMR spectrum of 3l
35404550556065707580859095105115125135145155165f1 (ppm)
52.4
112.4
117.9
124.0
124.7
129.1
129.4
131.2
131.3
133.0
145.6
167.2
N
N
O
O
13C NMR spectrum of 3l
S36
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.0f1 (ppm)
1.03
3.262.070.981.061.001.00
1.00
1.02
6.88
7.227.30
7.697.79
8.108.348.36
10.11
N
N
O
H
1H NMR spectrum of 3m
0102030405060708090100110120130140150160170180190f1 (ppm)
113.3
118.5
123.2
124.5
125.0
128.4
129.7
130.3
146.6
191.9
N
N
O
H
13C NMR spectrum of 3m
S37
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
1.03
1.05
0.942.081.00
1.961.07
6.94
7.277.347.737.757.76
7.868.368.41
N
N
N+ OO-
1H NMR spectrum of 3n
0102030405060708090100110120130140150f1 (ppm)
113.8
118.9
123.4
123.8
124.9
134.7
136.0
147.0
147.4
N
N
N+ OO-
13C NMR spectrum of 3n
S38
4.24.44.64.85.05.25.45.65.86.06.26.46.66.87.07.27.47.67.88.08.28.48.68.8f1 (ppm)
1.05
1.06
2.09
1.04
1.08
1.00
1.10
7.00
7.337.38
7.657.73
7.86
8.068.11
8.268.278.28
8.618.62
N
N
F
N
1H NMR spectrum of 3o
0102030405060708090100110120130140150160170f1 (ppm)
113.2
113.8
117.4
120.5
125.3
132.7
133.6
135.3
145.9
160.0
163.4
N
N
F
N
13C NMR spectrum of 3o
S39
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0f1 (ppm)
1.042.01
0.78
1.00
1.89
1.00
6.846.987.087.217.267.457.66
7.947.95
N
N
F
F
1H NMR spectrum of 3p
0102030405060708090100110120130140150160170f1 (ppm)
105.0
118.3
119.3
124.2
124.7
132.4
134.0
146.5
159.1
161.5
162.1
164.6
N
N
F
F
13C NMR spectrum of 3p
S40
3.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.093.05
1.191.08
1.64
1.061.001.14
1.04
1.06
3.964.02
6.846.94
7.237.297.617.707.71
7.927.93
9.68
N
N
O
O
O
H
1H NMR spectrum of 3q
0102030405060708090100110120130140150160170180190f1 (ppm)
56.4
56.6
109.6
113.1
113.4
118.3
123.3
126.7
134.9
146.2
150.2
154.4
189.9
N
N
O
O
O
H
13C NMR spectrum of 3q
S41
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
1.08
1.47
1.060.991.000.951.011.031.111.05
1.00
6.90
7.24
7.637.78
8.178.188.338.33
9.139.13
N
N
N
1H NMR spectrum of 3r
0102030405060708090100110120130140150f1 (ppm)
113.3
118.6
122.6
123.1
127.6
133.8
133.9
146.8
147.5
149.9
N
N
N
13C NMR spectrum of 3r
S42
3.43.84.24.65.05.45.86.26.67.07.47.88.28.69.09.4f1 (ppm)
1.04
1.661.00
3.050.880.97
1.01
1.00
0.99
6.78
7.257.307.387.39
7.737.827.858.128.14
8.508.52
9.38
N
N
N
1H NMR spectrum of 3s
0102030405060708090100110120130140150160f1 (ppm)
112.9
118.0
122.1
124.9
127.3
133.0
134.2
134.8
144.1
146.2
153.3
N
N
N
13C NMR spectrum of 3s
S43
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0f1 (ppm)
0.98
1.00
1.123.101.061.040.92
0.99
0.90
6.78
7.227.287.367.50
7.71
7.858.218.228.55
N
N
NH
1H NMR spectrum of 3t
05101520253035404550556065707580859095105115125135145f1 (ppm)
102.2
111.7
112.2
118.0
120.6
121.0
122.3
125.2
132.7
136.4
145.9
N
N
NH
13C NMR spectrum of 3t
S44
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0f1 (ppm)
0.891.03
1.052.001.051.040.940.96
1.00
0.89
6.606.666.78
7.157.227.307.387.53
7.718.368.38
9.27
N
N
NH
1H NMR spectrum of 3u
0102030405060708090100110120130140150f1 (ppm)
102.7
112.1
112.4
117.9
120.9
123.7
125.7
131.7
135.9
145.6
N
N
NH
13C NMR spectrum of 3u
S45
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.01
1.00
1.07
2.08
1.05
1.05
1.00
3.94
6.716.72
7.00
7.297.35
7.70
8.02
8.848.86
N
N
O
O
O
1H NMR spectrum of 3v
0102030405060708090100110120130140150160f1 (ppm)
52.1
107.4
114.0
116.7
118.3
125.8
125.9
134.5
143.2
146.9
149.0
159.1
N
N
O
O
O
13C NMR spectrum of 3v
S46
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
1.13
1.281.000.970.99
1.271.11
1.00
6.87
7.287.29
7.677.697.77
8.398.41
N
N
S
1H NMR spectrum of 3w
05101520253035404550556065707580859095105115125135145f1 (ppm)
112.9
118.0
123.8
124.5
125.9
133.5
146.2
N
N
S
13C NMR spectrum of 3w
S47
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
1.07
1.19
1.030.991.081.030.96
1.08
0.950.90
6.93
7.277.33
7.75
8.048.25
8.57
8.898.898.908.91
N
N
N
N
1H NMR spectrum of 3x
0102030405060708090100110120130140150f1 (ppm)
113.5
118.6
123.5
125.3
130.1
130.8
134.2
142.5
143.5
145.2
145.9
N
N
N
N
13C NMR spectrum of 3x
S48
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
1.19
1.301.03
1.041.001.261.04
0.991.00
6.86
7.217.45
7.707.75
8.27
8.648.658.668.668.848.84
N
N
N
1H NMR spectrum of 3y
0102030405060708090100110120130140150f1 (ppm)
113.2
118.4
122.3
123.0
124.0
133.4
135.2
146.7
148.9
149.3
N
N
N
13C NMR spectrum of 3y
S49
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0f1 (ppm)
3.14
1.00
1.092.201.052.01
1.00
2.34
7.107.117.137.13
7.597.657.73
8.13
N
N
N
1H NMR spectrum of 4a
0102030405060708090100110120130140150f1 (ppm)
18.5
111.1
117.9
118.7
120.8
123.3
127.7
133.1
134.0
134.3
146.2
N
N
N
13C NMR spectrum of 4a
S50
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0f1 (ppm)
3.11
0.98
1.931.010.891.03
0.980.921.00
0.93
2.34
7.127.147.607.787.90
8.158.178.198.32
9.12
N
N
N
1H NMR spectrum of 4b
0102030405060708090100110120130140150f1 (ppm)
18.5
117.9
120.7
122.3
123.0
123.1
127.6
133.6
134.1
145.9
147.5
150.0
N
N
N
13C NMR spectrum of 4b
S51
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.510.010.5f1 (ppm)
3.11
0.99
0.940.761.171.000.970.981.00
0.96
2.43
6.696.70
7.457.697.707.817.837.897.908.078.22
10.10
N
N
O
H
1H NMR spectrum of 4c
0102030405060708090100110120130140150160170180190f1 (ppm)
21.4
115.8
116.9
122.5
128.2
130.2
133.2
135.9
147.2
191.9
N
N
O
H
13C NMR spectrum of 4c
S52
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
3.16
3.00
1.011.04
0.991.01
0.98
1.02
2.43
3.92
6.656.666.796.806.816.81
7.297.297.44
7.92
8.698.70
N
N
O
O
O
1H NMR spectrum of 4d
0102030405060708090100110120130140150160f1 (ppm)
21.4
52.1
106.9
116.1
116.6
120.0
125.1
134.2
137.1
143.0
147.3
149.2
159.1
N
N
O
O
O
13C NMR spectrum of 4d
S53
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0f1 (ppm)
3.28
1.00
2.14
1.041.04
0.98
1.010.99
2.41
6.686.69
7.387.477.667.83
8.148.16
8.618.81
N
N
N
1H NMR spectrum of 4e
0102030405060708090100110120130140150f1 (ppm)
20.4
114.9
115.8
120.9
121.3
123.0
132.0
134.1
135.2
146.2
147.8
148.1
N
N
N
13C NMR spectrum of 4e
S54
6.46.56.66.76.86.97.07.17.27.37.47.57.67.77.87.98.08.18.28.38.48.5f1 (ppm)
1.04
1.03
2.07
1.06
0.98
2.10
1.09
1.00
1.00
6.76
7.027.04
7.50
7.59
7.657.67
7.80
7.85
7.937.967.988.02
8.308.32
N
N
1H NMR spectrum of 4f
05101520253035404550556065707580859095105115125135145f1 (ppm)
17.2
112.9
121.4
126.0
126.6
127.0
128.1
132.3
132.9
133.7
146.7
N
N
13C NMR spectrum of 4f
S55
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0f1 (ppm)
3.173.06
0.99
0.97
2.07
1.97
1.00
2.412.48
6.626.64
7.35
7.55
7.78
8.018.02
N
N
N
1H NMR spectrum of 4g
0102030405060708090100110120130140150f1 (ppm)
14.3
21.4
111.0
115.3
115.9
118.8
122.1
129.3
133.0
134.7
136.3
142.4
145.9
N
N
N
13C NMR spectrum of 4g
S56
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0f1 (ppm)
3.35
1.132.172.171.031.11
1.00
2.44
7.147.167.167.34
7.617.637.67
8.318.32
N
N
Cl
1H NMR spectrum of 4h
0102030405060708090100110120130140150f1 (ppm)
21.5
118.3
118.6
121.1
121.4
125.7
126.1
126.5
128.2
138.9
144.3
N
N
Cl
13C NMR spectrum of 4h
S57
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0f1 (ppm)
2.09
1.12
1.071.07
1.051.00
1.00
0.930.94
7.237.287.697.71
7.93
8.27
8.57
8.908.92
N
N
Cl
N
N
1H NMR spectrum of 4i
05101520253035404550556065707580859095105115125135145f1 (ppm)
119.1
121.4
122.0
125.1
130.0
135.0
142.8
143.5
145.4
145.5
146.0
N
N
Cl
N
N
13C NMR spectrum of 4i
S58
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
2.061.000.851.020.85
0.86
7.187.247.297.307.477.487.49
7.77
8.408.41
N
N
Cl
S
1H NMR spectrum of 4j
0102030405060708090100110120130140150f1 (ppm)
118.6
119.8
121.5
121.8
126.0
126.7
134.6
144.7
N
N
Cl
S
13C NMR spectrum of 4j
S59
2.63.03.43.84.24.65.05.45.86.26.67.07.47.88.28.6f1 (ppm)
3.08
1.00
1.203.10
3.271.040.97
7.157.157.177.18
7.527.557.897.968.02
8.168.16
N
N
Cl
1H NMR spectrum of 4k
05101520253035404550556065707580859095105115125135145f1 (ppm)
14.0
117.4
120.7
125.8
127.0
133.1
133.7
142.2
142.8
N
N
Cl
13C NMR spectrum of 4k
S60
0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0f1 (ppm)
3.09
0.97
0.961.013.011.030.881.021.00
2.44
6.68
7.307.327.427.507.577.637.977.998.02
N
N
F
F
F
1H NMR spectrum of 4l
05101520253035404550556065707580859095105115125135145f1 (ppm)
14.2
110.1
119.9
122.1
122.6
124.9
125.8
126.6
127.2
129.9
132.2
140.2
143.7
N
N
F
F
F
13C NMR spectrum of 4l
S61
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)
3.14
0.97
0.96
0.971.011.93
0.98
0.99
1.00
2.40
6.75
7.147.15
7.547.68
8.15
8.478.48
9.38
N
N
N
F
F
F
1H NMR spectrum of 4m
0102030405060708090100110120130140150160f1 (ppm)
14.2
110.6
117.7
119.4
122.9
125.1
127.4
134.0
140.6
144.2
144.3
153.4
N
N
N
F
F
F
13C NMR spectrum of 4m
S62
3.03.43.84.24.65.05.45.86.26.67.07.47.88.2f1 (ppm)
0.89
2.00
1.892.34
7.127.137.137.147.39
7.647.677.687.71
S
N
1H NMR spectrum of 5a
0102030405060708090100110120130140150f1 (ppm)
110.7
119.0
125.2
126.2
128.7
132.9
138.8
142.2
S
N
13C NMR spectrum of 5a
S63
-0.50.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)
2.48
2.71
7.507.527.687.70
N
S
N
1H NMR spectrum of 5b
0102030405060708090100110120130140150160170f1 (ppm)
16.5
19.3
111.1
118.7
129.6
132.6
137.3
148.9
165.0
N
S
N
13C NMR spectrum of 5b
S64
5.35.45.55.65.75.85.96.06.16.26.36.46.56.66.76.86.97.07.17.27.37.47.57.67.77.8f1 (ppm)
1.00
1.461.152.111.38
2.191.162.13
2.08
1.00
6.95
7.217.257.267.277.307.317.347.377.407.437.467.477.50
7.727.76
N
N
1H NMR spectrum of 5c
05101520253035404550556065707580859095105115125135145f1 (ppm)
105.8
110.6
110.9
118.9
121.3
127.9
132.1
137.1
138.1
138.5
139.8
N
N
13C NMR spectrum of 5c
S65
3.03.54.04.55.05.56.06.57.07.58.0f1 (ppm)
2.00
1.044.062.01
2.112.18
1.03
7.287.347.417.467.537.587.597.627.717.757.807.847.957.99
N
N
1H NMR spectrum of 5c'
35404550556065707580859095100105110115120125130135140145150f1 (ppm)
109.3
111.4
117.4
119.5
119.9
121.7
123.5
124.8
127.6
130.0
132.8
137.1
139.1
140.3
N
N
13C NMR spectrum of 5c'
S66
5.55.75.96.16.36.56.76.97.17.37.57.77.9f1 (ppm)
0.95
1.16
1.27
1.08
1.07
2.02
2.00
7.187.18
7.257.307.337.38
7.537.567.617.657.717.74
7.937.97
O
N
1H NMR spectrum of 5d
50556065707580859095100105110115120125130135140145150155160f1 (ppm)
104.5
111.6
111.6
118.9
121.6
125.2
128.8
132.7
134.6
153.7
155.4
O
N
13C NMR spectrum of 5d
S67
3.54.04.55.05.56.06.57.07.58.0f1 (ppm)
1.10
2.33
5.162.132.00
7.297.347.407.497.587.647.687.727.787.83
O
N
N
1H NMR spectrum of 5d'
0102030405060708090100110120130140150f1 (ppm)
111.8
112.3
112.3
118.5
124.0
127.4
130.5
133.2
137.4
149.1
154.5
O
N
N
13C NMR spectrum of 5d'
S68
Antibacterial assay
The screening panel consist of E. coli ATCC 25922, S. aureus ATCC 29213, P. aeruginosa ATCC 27853, K. pneumoniae BAA-1705 and A. baumannii BAA-1605. The bacterial strains were procured from ATCC (ATCC, Manassas, VA, USA) and Mueller Hinton broth II (MHB II) (Becton Dickinson) was used to propagate the bacteria. The compounds were serially diluted utilizing 2-fold dilutions and bacteria were subsequently added to a final count of 104-105 cfu/ml. The 96-well plates were incubated at 37°C for 24 hrs and the antimicrobial activity was determined by visual inspection. The MIC of the active compounds was determined and was defined as the lowest concentration of the compound that inhibited visible growth after 24 hrs.
References
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2. F. Liang, M. Gibney, V. Yeh, X. Li, V. Molteni, D. Shaw, A. M. Berman, S. Lewis, J. Loren and V. Furminger, PCT Int Appl, WO 2013033620 A1, 2013.