Full NMR assignment of new acridinyl-chalcones, pyrazolino-acridines, and spiro[imidazo[1,5-b]pyrazole-4,9′-acridines]

Full text of DOI:10.1002/mrc.5028

Imrich Ján (Orcid ID: 0000-0003-1795-951X)
Vilkova Maria (Orcid ID: 0000-0003-2833-7361)
Full NMR assignment of new acridinyl-chalcones, pyrazolino-acridines and
spiro[imidazo[1,5-b]pyrazole-4,9'-acridines]
Paulína Slepčíková1, Ivan Potočňák2, Tibor Béres3, Dávid Jáger4, Ján Imrich5, Mária Vilková5
ORCID
Paulína Slepčíková
Ivan Potočňak
Tibor Béres
0000-0002-9168-3622
0000-0001-6923-8816
0000-0002-5845-6903
0000-0003-1573-1407
0000-0003-1795-951X
0000-0003-2833-7361
Dávid Jáger
Ján Imrich
Mária Vilková
1Department of Organic Chemistry, Institute of Chemistry, Faculty of Science, P. J. Šafárik University, Moyzesova
11, 040 01, Košice, Slovak Republic
2Department of Inorganic Chemistry, Institute of Chemistry, Faculty of Science, P. J. Šafárik University,
Moyzesova 11, 040 01, Košice, Slovak Republic
3Centre of the Region Haná for Biotechnological and Agricultural Research, Department of the Phytochemistry,
Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
4Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, 040 01 Košice, Slovak Republic
5Laboratory of NMR, Institute of Chemistry, Faculty of Science, P. J. Šafárik University, Moyzesova 11, 040 01,
Košice, Slovak Republic
Correspondence
Mária Vilková, Institute of Chemistry, Faculty of Science, P. J. Šafárik University, Moyzesova 11, 040
01 Košice, Slovak Republic.
Email: maria.vilkova@upjs.sk
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through the copyediting, typesetting, pagination and proofreading process which may lead to
differences between this version and the Version of Record. Please cite this article as doi:
10.1002/mrc.5028
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KEYWORDS
Spiro acridine
Pyrazole
Carbothioamide
1H, 13C and 15N NMR studies
Single crystal X-ray crystallography
1
INTRODUCTION
In our continuing search for pharmacologically and structurally interesting acridine
derivatives, three new chalcones of acridine 2A–C have been synthesized and their
antiproliferative activity investigated.[1] Among these, (2E)-3-(acridin-9'-yl)-1-(2'',6''-
dimethoxyphenyl)prop-2-en-1-one (2C), most effective against human colorectal HCT116
cells (IC50 = 4.1 μmol/L), was selected for further studies. Inhibition of cell proliferation was
associated with cell cycle arrest in G2/M phase and dysregulation of α, α1 and β5 tubulins. In
addition, the compound causes a disruption of the mitochondrial membrane potential and an
increase in the number of cells with sub G0/G1 DNA content, which is considered as marker
of apoptosis. It also up-regulates proapoptotic expression of Bax, down-regulates anti-
apoptotic expression of Bcl-2, Bcl-xL and modulates MAPKs and Akt signalling pathways.[1]
In another work [2] we found that 2C had potent antiproliferative and cytotoxic effects on
parental cancer cell lines (PAR, Colo 205) and their resistant sub-lines expressing ABCB1. The
combination of 2C with the anticancer drug doxorubicin led to better inhibition of the both
ABCB1 expressing cell lines. These results demonstrated a dual potential of chalcone 2C to
act as a chemotherapeutic as well as a chemosensitizing agent in resistant T-cell lymphoma
and colon cancer, with higher sensitivity to cancer cells.[2]
In this study, the chalcones 2A-C were let to react with hydrazine hydrate to give new
9'-(3-R-4,5-dihydro-1H-pyrazol-5-yl)acridines 3A-C. The 3B,C pyrazolo-acridines, though
prepared, were not used in further syntheses due to low yields and stability at higher
temperatures. In contrast to 3B,C, the pyrazole 3A reacted with phenyl- and p-nitrophenyl
isothiocyanate via its 1-NH nitrogen to form 5-(acridin-9'-yl)-N-R1-3-R-4,5-dihydro-1H-
pyrazole-1-carbothioamide 4Aa and 4Ab, respectively. Both these products then
spontaneously and rapidly spirocyclized upon standing in DMSO-d6 to yield new acridine
pentacyclic spiro compounds, 5-substituted-2-phenyl-3,3a,5,6-tetrahydro-10'H-spiro[acridine-
9',4-pyrazolo[1,5-c]imidazole]-6-thiones 5Aa and 5Ab, resp., in a similar way as we have
repeatedly found in the past for various 9-acridinyl derivatives.[35]
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In the previous studies, [1,2] no NMR data for compounds 2A–C were presented. Herein,
we present the complete NMR data for the derivatives 2A–C, 3A,B, 4Aa, 4Ab and 5Aa, 5Ab,
and high-resolution mass spectra (HR-MS) and X-ray analysis for the derivatives 2A and 4Ab
(Table 1).
2
RESULTS AND DISCUSSION
Acridine-9-carbaldehyde (1) was prepared according to a previously published
procedure.[6] Base-catalysed reaction of aldehyde 1 with acetophenones in ethanol at room
temperature gave chalcones 2A–C (Scheme 1). Chalcones 2A,B were refluxed with hydrazine
hydrate in ethanol to give pyrazolines 3A,B. Next, pyrazoline 3A was treated with phenyl- and
4-nitrophenylisothiocyanate at 80 °C in ethanol. The resulting carbothioamides 4Aa,b were
isolated by filtration of the precipitate formed in the reaction mixture.
1H and 13C NMR chemical shifts of compounds 2A–C are given in Table 2. The 1D NMR
spectra of 2A (Figures S1 and S2) showed the acridin-9-yl 1H NMR signals at H 8.25 (2H, d,
J = 8.7 Hz, H-1',8'), 7.59 (2H, t, J = 7.8 Hz, H-2',7'), 7.83 (2H, t, J = 7.3 Hz, H-3',6'), 8.32 (d,
J = 8.8 Hz, H-4',5') (Table 2) and 13C NMR signals at C 125.4 (C-1',8'), 126.7 (C-2',7'), 130.6
(C-3',6'), 130.0 (C-4',5'), 141.2 (C-9'), 124.1 (C-8'a,9'a), 148.4 (C-4'a,10'a) (Table 2). In
addition, signals at H 7.59 (1H, d, J = 16.0 Hz, H-2) and 8.68 (1H, d, J = 16.0 Hz, H-3) revealed
the presence of a Z-chalcone fragment.
1
The structures of 3A,B were fully characterized by H,1H correlation spectroscopy
1
(COSY, Figures S18 and S24), H,13C heteronuclear single-quantum coherence (HSQC,
1
Figures S19 and S25), H,13C heteronuclear multiple-bond correlation (HMBC, Figures S20
1
1
and S26) and H,15N-HMBC (Figures S21 and S27) spectra. The aliphatic region of the H
NMR spectra (Figures S16 and S22) contain one doublet of doublets of doublets at H 3.36
(1H, ddd, J = 16.8, 13.2, 1.6 Hz for 3A) and 3.35 (1H, ddd, J = 16.8, 12.8, 1.7 Hz for 3B) and
one doublet of doublet at H 3.85 (1H, dd, J = 16.8, 13.2 Hz for 3A) and 3.83 (1H, dd, J = 16.8,
12.8 Hz for 3B) corresponding to H-4a and H-4b, respectively. The remaining signals of the
pyrazole spin system appear in the typical aromatic proton frequency range (H 8.00 (1H, dd, J
= 5.4, 1.6 Hz, H-1), 6.39 (1H, td, J = 13.0, 5.4 Hz, H-5) for 3A and H 7.79 (1H, d, J = 5.6 Hz,
H-1), 6.34 (1H, td, J = 12.8, 5.6 Hz, H-5) for 3B) (Table 2 and Figures S16 and S22). HSQC
connectivities (Figures S19 and S25) were used to identify protonated carbons and HMBC
connectivities (Figures S20 and S26) were used to assign nonprotonated carbons.
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1D and 2D NMR spectra of 4Aa and 4Ab in DMSO-d6 and CDCl3 are summarized in
1
13
Table 3. Both H NMR (Figures S64) and C NMR (Figures S65) signals of 4Ab measured
immediately after dissolution in DMSO-d6 were doubled. The same was observed in 1H NMR
(Figures S39) and 13C NMR (Figures S40) spectra of 4Aa upon standing in DMSO-d6 solution.
The doubling of signals demonstrates that pyrazoline-thioamides 4Aa,b react further in
DMSO-d6 to novel compounds, namely spiro compounds of 9,10-dihydroacridine 5Aa,b
(Scheme 1, Table 4). This spirocyclization proceeded through an intramolecular nucleophilic
attack of the thioamidic NH-7 nitrogen of the pyrazoline on the electrophilic C-9' carbon of
acridine. The compounds 4A and 5A were obtained as an inseparable mixture. No
spirocyclization was observed in the CDCl3 solution (Table 3, Figures S33–S38 and Figures
S57–S63).
1
The aliphatic region of the H NMR spectrum (Figure S64) of 4Ab/5Ab in DMSO-d6
contained pyrazole proton signals at H 3.62 (1H, dd, J = 18.7, 8.3 Hz, H-4a), 4.40 (1H, dd, J
= 18.7, 12.8 Hz, H-4b) for 4Ab and at H 2.37 (1H, dd, J = 18.0, 8.6 Hz, H-4a), 3.37 (1H, dd,
J = 18.0, 11.6 Hz, H-4b) and 5.10 (1H, dd, J = 11.6, 8.6 Hz, H-5) for 5Ab. The H-5 proton
signal of 4Ab derivative also appeared at H 7.34 (1H, dd, J = 12.8, 8.3 Hz). Signals of acridine
and a phenyl substituent on C-3 appeared in the aromatic region (Table 3, Figure S64). HSQC
connectivities were used to identify the protonated carbons (Figures S69). In particular, Figures
S71 and S72 show the unambiguous assignment of the aromatic carbons of acridin-9-yl and
phenyl moieties of both derivatives 4Ab and 5Ab. Quarternary carbons C-3 (C 156.9), C-6
(C 173.7) and C-9' (C 143.7)of 4Ab (Figure S74 and S75) and C-3 (C 161.7), C-6 (C 178.7)
and C-9' (C 75.6) of 5Ab (Figure S74 and S75) were assigned by their HMBC connectivity
with adjacent protons H-4, H-5 and H-7. Also, the unambiguous assignment of N-1 (N -183.1),
N-2 (N -65.9) and N-7 (N -249.0) nitrogen atoms in 4Aa and N-1 (N -183.7), N-2 (N -59.6)
and N-7 (N -220.6) in 5Aa was made through their observed HMBC connectivities with H-4
and H-5 (Figure S79).
NOESY experiments performed with the 4Ab derivative allowed the assignment of relative
stereochemistry at C-5 carbon. The 2D NOESY spectrum measured in DMSO-d6 was of little
help. In contrast, in the 2D NOESY spectrum measured in CDCl3, a strong correlation was
observed between protons H-5 and H-4b, which showed that these protons were in a syn-
periplanar orientation (the same side of the pyrazole ring). In addition, the weak NOESY
correlation observed between H-5 and H-4a indicated that these protons were in an anticlinal
orientation (opposite side of the pyrazole ring, Figure S60). The results were supported by
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a coupling constant 3JH5H4b = 12.8 Hz (indicating the syn-periplanar orientation) and a value of
3JH5H4a = 8.7 Hz (indicating an anticlinal orientation, Table 3). The findings are consistent with
the X-ray analysis (Figure 4).
The structures of derivatives 2A and 4Ab were confirmed by X-ray analysis. Molecular
structures of 2A and 4Ab are shown in Figure 4, while crystal data and structure refinement
appear in Table 5. As expected, all aromatic moieties in both structures are planar. However,
the acridine and phenyl ring systems are not coplanar, mainly due to the twisting of the acridine
group along the C1–C3 in 2A and C3–C5 bond in 4Ab. The twist is apparently caused by
intermolecular hydrogen bonds; C2—H2···N10i (i = 1 – x, 2 – y, 1 – z) in 2A, and C4—
H4B···N10i (i = 2 – x, 1 – y, 2 – z) in 4Ab (Table S9), joining two inversely related molecules
of the title compounds into dimers (Figures S80 and S81). Obviously, the hydrogen bonds in
4Ab play a vital role in the arrangement of the molecule. Due to the intramolecular N7—
H7···N2 and C2'''—H2'''···S8 hydrogen bonds (Table S9), the nitrophenyl, pyrazole and phenyl
rings are almost coplanar. Moreover, intermolecular hydrogen bonds assemble the 4Ab
molecules to a final supramolecular arrangement (see below).
The search for - interactions in 2A and 4Ab has shown that above formed dimer in 2A
is further stabilized by a pair of centrosymmetrically related - interactions between aromatic
rings with Cg1 and Cg2i centroids (Figure S80). The dimer in 4Ab is supported by -
interaction between rings with Cg1 and Cg1i centroids and two pairs of centrosymmetrically
related - interactions between rings with Cg1 and Cg2i, and Cg2 and Cg3i centroids (Figure
S81). Finally, the dimers are arranged in zig-zag layers due to the intermolecular C5'''—
H5'''···O8'''iii ( iii = 1 – x, ½ + y, ½ – z) hydrogen bond system (Table S9). The crystal structure
is stabilized by nonspecific interactions between these layers.
3
EXPERIMENTAL
Analytical TLC was performed on pre-coated aluminium plates of silica gel 60 F254
(Merck, Germany), and the compounds were visualized in the UV light. The melting points
were recorded on a Boetius instrument and are uncorrected. Nuclear magnetic resonance data
were collected on a Varian VNMRS 600 MHz spectrometer operating at 599.87 MHz for 1H,
150.84 MHz for 13C, and 60.79 MHz for 15N. The concentration of all samples was
approximately 10 mg/0.6 mL of DMSO-d6 (chemical shifts were referenced to residual solvent
peak: 1H NMR 2.50 ppm and 13C NMR 39.5 ppm) or CDCl3 (chemical shifts were referenced
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to TMS 0.0 ppm). NMR data were recorded at 300 K, with chemical shifts  reported in parts
per million and coupling constants J in Hertz. The 15N chemical shifts were obtained from two
dimensional 1H,15N-HMBC experiments with gradient coherence selection, performed using a
15
standard pulse sequence from the Varian pulse library. For the N chemical shifts, CH3NO2
was used as an external reference (0.0 ppm). 2D NMR experiments gCOSY, zTOCSY,
NOESY, gHSQC and gHMBC were performed using the standard Varian software. All data
were analyzed using MNova 7.1.1 (2012) software. The spectral acquisition parameters are
summarized in Tables S1 and S2.
4
CONCLUSIONS
In conclusion, we have described the full assignment of 1H, 13C and 15N NMR signals as
well as the x-ray and HR-MS data of acridine bearing chalcone or pyrazole fragments,
including one promising new potential antitumor agent.
ACKNOWLEDGEMENTS
This work was supported by the Grant Agency for Science of the Slovak Ministry of
Education (VEGA), a grant. no. 1/0148/19.
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REFERENCES
[1] P. Takáč, M. Kello, M. Bago Pilátová, Z. Kudličková, M. Vilková, P. Slepčíková, P. Petik,
J. Mojžiš, Chem. Biol. Interact. 2018, 292, 37–49.
[2] M. Čižmáriková, P. Takáč, G. Spengler, A. Kincses, M. Nové, M. Vilková, J. Mojžiš,
Anticancer Res. 2019, 39, 6499–6505.
[3] M. Vilková, M. Prokaiová, J. Imrich, Tetrahedron 2014, 70, 944-961 and references cited
therein.
[4] D. Sabolová, M. Vilková, J. Imrich, I. Potočňák, Tetrahedron Lett. 2016, 57, 5592-5595.
[5] M. Vilková, M. Šoral, M. Bečka, I. Potočňák, D. Sabolová, T. Béres, M. Dušek, J. Imrich,
Magn. Reson. Chem. 2019, 57, 1–11.
[6] M. Vilková, L. Ungvarská Maľučká, J. Imrich, Magn. Reson. Chem. 2016, 54, 8–16.
This article is protected by copyright. All rights reserved.

R
O
R
3
N
1
HN
1
2
3
CHO
5
8'
5'
1'
8'
5'
1'
4'
acetophenone
NaOH
8'a
9'a
8'a
9'a
NH2NH2xH2O
9'
9'
MeOH
rt, 60 min
EtOH
reflux, 2h
4'a
N
10'a N 4'a
10'a N
4'
1
2A: R = Ph
2B: R = 4-CH3O-Ph
3A: R = Ph
3B: R = 4-CH3O-Ph
2C: R = 2,6-diCH3O-Ph
R
N
3
S
N
R1
NH
R
N1
4
N1
5
5
9'
3
6
7 N
8'a
4
R1
1'
4'
1'
S
standing
in DMSO-d6
8'a
9'a
4'a
9'a
R1NCS
rt
EtOH
reflux
10'a
10'a
4'a
N
N
H
5'
5'
4'
4Aa: R1 = Ph
4Ab: R1 = 4-NO2-Ph
5Aa: R1 = Ph
5Ab: R1 = 4-NO2-Ph
SCHEME 1
Synthesis
of
5-(acridin-9'-yl)-N-substituted-3-phenyl-4,5-dihydro-1H-pyrazole-1-
carbothioamides 4Aa,b and 2-phenyl-5-substituted-3,3a-dihydro-10'H-spiro[imidazo[1,5-b]pyrazole-4,9'-
acridine]-6(5H)-thione 5Aa,b. The structures are shown along with atom numbering.
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TABLE 1
Physico-chemical data for compounds 2A–C, 3A,B and 4Aa,b
No.
Name
Melting point
[°C]
Yield
[mg]
132
155
159
98
82
52
63
Yield
[%]
88
94
89
93
79
73
81
2A
2B
2C
3A
3B
(2E)-3-(acridin-9'-yl)-1-phenylprop-2-en-1-one
(2E)-3-(acridin-9'-yl)-1-(4''-methoxyphenyl)prop-2-en-1-one
(2E)-3-(acridin-9'-yl)-1-(2'',6''-dimethoxyphenyl)prop-2-en-1-one
9'-(3-phenyl-4,5-dihydro-1H-pyrazol-5-yl)acridine
148–149
143–144
177–178
208–209
200–201
254–255
261–262
9'-[3-(4''-methoxyphenyl)-4,5-dihydro-1H-pyrazol-5-yl]acridine
5-(acridin-9'-yl)-N,3-diphenyl-4,5-dihydro-1H-pyrazole-1-carbothioamide
5-(acridin-9'-yl)-N-(4''-nitrophenyl)-3-phenyl-4,5-dihydro-1H-pyrazole-1-carbothioamide
4Aa
4Ab
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TABLE 2
1H, 13C and 15N NMR data for compounds 2A–C and 3A,Ba,b
2A
2B
2C
3A
3B
No.
H (mult., J)
C
H (mult., J)
C
H (mult., J)
C
H (mult., J)
8.00 (dd, 5.4, 1.6)
C
N
-235.9
H (mult., J)
7.79 (d, 5.6)
C
N
-237.2
1
187.1 (C)
193.3 (C-1)
189.0 (C)
2
3
4a
7.59(d, 16.0)
8.68(d, 16.0)
133.0 (CH) 7.58 (d, 16.0)
139.0 (CH) 8.66 (d, 16.0)
132.7 (CH)
138.1 (CH)
6.95 (d, 16.5)
138.9 (CH)
138.4 (CH)
-40.8
-46.1
8.24 (d, 16.5)
8.21 (d, 8.3)
7.56 (ddd, 8.6, 6.5, 126.2 (CH)
1.2)
7.80 (ddd, 8.7, 6.5, 130.1 (CH)
1.4)
8.24 (d, 8.6)
148.4 (C)
148.6 (C)
3.36 (ddd, 16.8, 13.2, 1.6)
3.35 (ddd, 16.8, 12.8,
1.7)
3.83 (dd, 16.8, 12.8)
6.34 (td, 12.8, 5.6)
8.56 (d, 8.9)
41.3 (CH2)
41.7 (CH2)
4b
5
1',8'
2',7'
3.85 (dd, 16.8, 13.2)
6.39 (td, 13.2, 5.4)
8.55 (d, 9.0)
57.5 (CH)
125.0 (CH)
57.4 (CH)
125.0 (CH)
125.5 (CH)
8.25 (d, 8.7)
7.59 (t, 7.8)
125.4 (CH) 8.25 (d, 8.3)
125.4 (CH)
125.4 (CH)
7.57 (ddd, 8.7, 6.6, 126.4 (CH)
1.2)
7.81 (ddd, 8.3, 6.5, 130.2 (CH)
1.4)
7.58 (ddd, 9.0, 6.4, 1.4)
7.58 (t, 7.0)
126.7 (CH)
130.6 (CH)
125.5 (CH)
129.9 (CH)
3',6'
7.83 (t, 7.3)
8.32 (d, 8.8)
7.83 (ddd, 8.8, 6.4, 1.3)
8.18 (d, 8.8)
7.83 (t, 7.0)
8.17 (d, 8.7)
129.8 (CH)
4',5'
9'
130.0 (CH) 8.27 (d, 8.4)
141.2 (C)
130.2 (CH)
140.9 (C)
130.1 (CH)
140.4 (C)
130.1 (CH)
145.2 (C)
130.0 (CH)
145.4 (C)
10'
-74.0
-74.1
8'a,9'a
4'a,10'a
1''
2'',6''
3'',5''
4''
124.1 (C)
148.4 (C)
137.5 (C)
129.0 (CH) 8.09 (d, 8.8)
129.1 (CH) 7.01 (d, 8.8)
133.7 (CH)
124.0 (C)
148.7 (C)
130.4 (C)
131.2 (CH)
114.1 (CH)
164.0 (C)
55.6 (CH3)
123.8 (C)
148.6 (C)
117.8 (C)
158.1 (CH)
104.2 (CH)
131.7 (C)
124.3 (C)
148.3 (C)
132.9 (C)
125.7 (CH)
128.6 (CH)
128.3 (CH)
124.3 (C)
148.2 (C)
125.6 (C)
127.2 (CH)
114.1 (CH)
159.6 (C)
8.10 (d, 6.9)
7.55 (t, 7.8)
7.64 (t, 7.4)
7.74 (d, 7.0)
7.44 (t, 7.6)
7.37 (t, 7.4)
7.67 (d, 8.7)
7.00 (d, 8.7)
6.68 (d, 8.4)
7.39 (t, 8.4)
3.92 (s)
OCH3
3.90 (s)
56.1 (OCH3)
55.2 (O CH3)
a in ppm, J in Hz
bCompounds were recorded at 600 MHz for 1H, 150 MHz for 13C and 61 MHz for 15N in CDCl3 (2A–C) and DMSO-d6 (3A,B).
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TABLE 3
1H, 13C and 15N NMR data for compounds 4Aa and 4Aba,b
4Aa (DMSO-d6)
H (mult., J) C
4Ab (DMSO-d6)
4Aa (CDCl3)
4Ab (CDCl3)
No.
N
-187.7
-65.0
H (mult., J)
C
N
-183.1
-65.9
H (mult., J)
C
N
-188.2
-68.7
H (mult., J)
C
N
-184.5
-70.8
1
2
3
155.7 (C)
156.9 (C)
154.6 (C)
155.8 (C)
4a
4b
5
3.55 (dd, 18.6, 8.4)
4.36 (dd, 18.6, 13.1)
7.31 (dd, 13.1, 8.4)
3.62 (dd, 18.7, 8.3)
4.40 (dd, 18.7, 12.8)
7.34 (dd, 12.8, 8.3)
3.52 (dd, 18.0, 8.4)
4.17 (dd, 18.0, 13.2)
7.31 (dd, 13.2, 8.4)
3.59 (dd, 18.5, 8.7)
4.22 (dd, 18.5, 12.8)
7.28 (dd, 12.8, 8.7)
41.5 (CH2)
41.5 (CH2)
42.2 (CH2)
42.3 (CH2)
59.6 (CH)
174.4 (C)
59.8 (CH)
173.7 (C)
59.2 (CH)
175.0 (C)
59.2 (CH)
173.3 (C)
6
7
10.38 (s)
-250.3
10.77 (s)
-249.0
9.37 (s)
-253.0
9.71 (s)
-251.7
1'
2'
3'
4'
5'
6'
7'
8'
8.73 (d, 9.0)
124.4 (CH)
126.2 (CH)
129.9 (CH)
129.9 (CH)
130.7 (CH)
129.6 (CH)
126.1 (CH)
122.9 (CH)
144.5 (C)
8.73 (d, 9.0)
124.2 (CH)
126.4 (CH)
130.0 (CH)
130.8 (CH)
129.9 (CH)
129.7 (CH)
126.3 (CH)
122.7 (CH)
143.7 (C)
8.57 (d, 8.9)
123.4 (CH)
126.5 (CH)
129.7 (CH)
130.7 (CH)
131.4 (CH)
129.4 (CH)
126.5 (CH)
122.7 (CH)
143.1 (C)
8.56 (d, 8.8)
123.1 (CH)
126.7 (CH)
129.8 (CH)
130.9 (CH)
131.6 (CH)
129.5 (CH)
126.7 (CH)
122.3 (CH)
142.2 (C)
7.70 (ddd, 9.0, 6.5, 1.4)
7.87 (ddd, 8.8, 6.5, 1.2)
8.18 (d, 8.8)
7.73 (ddd, 9.0, 6.5, 1.2)
7.88 (ddd, 8.7, 6.5, 1.2)
8.19 (d, 8.7)
7.64 (ddd, 8.9, 6.6, 1.3)
7.80 (ddd, 8.7, 6.5, 1.1)
8.27 (d, 8.7)
7.67 (ddd, 8.9, 6.5, 1.3)
7.83 (ddd, 8.8, 6.5, 1.1)
8.29 (d, 8.8)
8.18 (d, 8.8)
8.19 (d, 8.8)
8.25 (d, 8.5)
8.27 (d, 8.8)
7.78 (ddd, 8.8, 6.5, 1.3)
7.51 (ddd, 8.8, 6.5, 1.4)
7.96 (d, 8.8)
7.78 (ddd, 8.8, 6.5, 1.3)
7.50 (ddd, 9.0, 6.5, 1.4)
7.92 (d, 9.0)
7.70 (ddd, 8.5, 6.5, 1.2)
7.41 (ddd, 9.0, 6.5, 1.3)
7.96 (d, 9.0)
7.71 (ddd, 8.8, 6.5, 1.2)
7.41 (ddd, 9.0, 6.5, 1.3)
7.88 (m)
9'
10'
8'a
9'a
4'a
10'a
1''
2'',6''
3'',5''
4''
1'''
-74.3
-73.7
-77.3
-73.7
122.6 (C)
123.9 (C)
148.1 (C)
148.5 (C)
130.5 (C)
127.6 (CH)
128.8 (CH)
131.0 (CH)
139.3 (C)
125.2 (CH)
128.1 (CH)
125.0 (CH)
122.5 (C)
124.0 (C)
148.1 (C)
148.5 (C)
130.2 (C)
127.7 (CH)
128.9 (CH)
131.4 (CH)
145.7 (C)
123.5 (CH)
123.8 (CH)
143.0 (C)
123.1 (C)
124.3 (C)
148.7 (C)
149.2 (C)
130.3 (C)
127.0 (CH)
129.1 (CH)
131.3 (CH)
138.5 (C)
124.0 (CH)
128.6 (CH)
125.5 (CH)
122.9 (C)
124.3(C)
148.7 (C)
149.2 (C)
129.8 (C)
127.2 (CH)
129.2 (CH)
131.8 (CH)
144.4 (C)
121.7 (CH)
124.5 (CH)
143.8 (C)
8.10 (dd, 7.9, 1.8)
8.12 (dd, 8.1, 1.7)
7.57 (m)
7.57 (m)
7.86 (dd, 8.1, 1.5)
7.52 (m)
7.52 (m)
7.88 (m)
7.55 (m)
7.55 (m)
-
7.54 (t, 7.5)
7.57 (t, 7.5)
-
7.91 (d, 9.2)
8.16 (d, 9.2)
-
-
2''',6''' 7.45 (dd, 8.4, 1.2)
3''',5''' 7.28 (t, 7.2)
4'''
7.93 (d, 9.3)
8.16 (d, 9.3)
7.56 (d, 7.3)
7.30 (dd, 8.4, 7.2)
7.14 (t, 7.2)
7.11 (dd, 7.2, 1.2)
NO2
-10.2
-10.2
a in ppm, J in Hz
bCompounds were recorded at 600 MHz for 1H, 150 MHz for 13C and 61 MHz for 15N.
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TABLE 4
1H, 13C and 15N NMR data for compounds 5Aa and 5Aba,b
5Aa
5Ab
No.
H (mult., J)
C
N
H (mult., J)
C
N
-183.7
-59.6
1
2
-186.8
-56.6
3
160.2 (C)
161.7 (C)
4a
4b
5
6
2.44 (dd, 18.0, 8.4)
3.33 (dd, 18.0, 12.0)
5.09 (dd, 12.0, 8.4)
2.37 (dd, 18.0, 8.6)
3.37 (dd, 18.0, 11.6)
5.10 (dd, 11.6, 8.6)
34.4 (CH2)
34.0 (CH2)
73.8 (CH)
180.1 (C)
74.0 (CH)
178.7 (C)
7
-219.3
-220.6
1'
2'
3'
4'
5'
6'
7'
8'
7.03 (m)
126.4 (CH)
120.3 (CH)
130.0 (CH)
115.0 (CH)
114.1 (CH)
128.9 (CH)
120.1 (CH)
128.5 (CH)
75.3 (C)
7.03 (dd, 8.0, 1.3)
6.87 (ddd, 8.0, 7.4, 1.2)
7.31 (ddd, 8.2, 7.4, 1.2)
7.09 (dd, 8.2, 1.2)
6.90 (dd, 8.4, 1.2)
7.15 (ddd, 8.4, 7.2, 1.4)
6.78 (ddd, 8.2, 7.2, 1.2)
7.47 (m)
125.7 (CH)
120.8 (CH)
130.3 (CH)
115.2 (CH)
114.3 (CH)
129.2 (CH)
120.4 (CH)
127.9 (CH)
75.6 (C)
6.85 (ddd, 8.4, 6.6, 1.2)
7.28 (ddd, 8.4, 6.6, 1.8)
7.03 (m)
6.83 (dd, 8.4, 1.2)
7.12 (m)
6.81 (ddd, 8.4, 6.6, 1.2)
7.55 (m)
9'
10'
8'a
9'a
4'a
10'a
1''
2'',6''
3'',5''
4''
9.55 (s)
-283.4
9.70 (s)
-282.9
117.0 (C)
116.3 (C)
137.5 (C)
138.3 (C)
130.7 (C)
126.7 (CH)
128.8 (CH)
130.5 (CH)
138.5 (C)
127.0 (CH)
128.1 (CH)
126.2 (CH)
116.4 (C)
115.8 (C)
137.4 (C)
138.5 (C)
130.4 (C)
126.9 (CH)
128.8 (CH)
130.9 (CH)
144.5 (C)
126.4 (CH)
123.5 (CH)
144.0 (C)
7.62 (dd, 7.8, 1.2)
7.42 (t, 7.8)
7.45 (t, 7.8)
7.63 (d, 7.0)
7.41 (t, 7.4)
7.47 (m)
1'''
2''',6'''
3''',5'''
4'''
NO2
6.98 (dd, 8.6, 1.3)
7.12 (m)
7.03 (m)
7.36 (d, 9.2)
8.03 (d, 9.2)
-10.7
a in ppm, J in Hz
bCompounds were recorded at 600 MHz for 1H, 150 MHz for 13C and 61 MHz for 15N in DMSO-d6.
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TABLE 5
Crystal data and structure refinement for 2A and 4Ab
Cmpd
2A
4Ab
Empirical formula
Formula weight
Temperature
Wavelength
Crystal system
Space group
C22H15NO
309.35
173(2) K
0.71073 Å
Triclinic
C29H21N5O2S
503.57
173(2) K
0.71073 Å
Monoclinic
P21/c
P 
Unit cell dimensions
a = 16.5050(7) Å
a = 7.2530(3) Å
b = 8.8491(4) Å
c = 12.8946(6) Å
776.86(6) Å3
2
 = 109.889(4)°
 = 91.500(4)°
 = 92.373(4)°
b = 12.8008(4) Å  = 107.241(4)°
c = 11.9517(5) Å
2411.66(17) Å3
4
Volume
Z
Density (calculated)
Absorption coefficient
F(000)
Crystal size
 range for data
collection
1.322 Mg/m3
0.081 mm-1
324
1.387 Mg/m3
0.173 mm-1
1048
0.365 x 0.257 x 0.047 mm3
3.215 to 26.493°
0.238 x 0.201 x 0.104 mm3
2.959 to 26.496°
Index ranges
-5  h  9, -11  k  10, -16  l  14
-20  h  16, -16  k  10, -14  l  14
Reflections collected
Independent reflections
Completeness to  =
25.242°
5183
10462
3200 [R(int) = 0.0129]
99.8 %
4973 [R(int) = 0.0209]
99.9 %
Absorption correction
Max. and min.
transmission
Refinement method
Data / restraints /
parameters
Analytical
0.996 and 0.978
Analytical
0.985 and 0.969
Full-matrix least-squares on F2
3200 / 0 / 217
Full-matrix least-squares on F2
4973 / 0 / 338
Goodness-of-fit on F2
Final R indices [I > 2(I)]
R indices (all data)
Largest diff. peak and
hole
1.008
1.054
R1 = 0.0436, wR2 = 0.1006
R1 = 0.0646, wR2 = 0.1144
0.199 and -0.161 e.Å-3
R1 = 0.0432, wR2 = 0.0909
R1 = 0.0631, wR2 = 0.1001
0.264 and -0.267 e.Å-3
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7.57
128.9
7.57
131.4
8.12
127.7
H
H
1''
130.2
H
N
H
-65.9
7.93
N
123.5
156.9
41.5
H
N
-183.1
1
10.77
O–
3
N
8.16
123.8
H4.40
145.7
NH
N+
7
O–
173.1
H
N
1'''
-249.0
H
5
H
H
6
3.62
-10.2 N+
S
7.H34
59.8
H
143.0
O
7.92
8.73
124.2
1'
124.0
S
H
H
H
H
122.7
O
7.50
126.3
143.7
7.73
122.5
126.4
7.78
129.7
7.88
130.0
N
148.5
140.1
N
8.19
129.9
8.19
130.8
-73.7
H
H
FIGURE 1 Selected 1H,13C-HMBC () and 1H,15N-HMBC () correlations facilitating structural elucidation
of 4Ab (left) and 1H, 13C and 15N chemical shifts (right).
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H
7.41
128.8
7.63
126.9
S
H
H
N
7.47
130.9
1''
O–
N+
3
-59.6
N
S
N
1
6
130.4
8.03
7.36
1''
-18N3.7
O–
3
161.7
126.4
123.5
5
1
7
H
H
6
178.7
1'''
N
+
H3.37
144.5
7.47
34.0
5
H
H
7
74.0
1'''
-10.7
N144.0
N
H
7.03
O
-220.6
H2.37
125.7
127.9
116.4
138.5
5.10
H
H
H
H
O
1'
1'
75.6
6.87
6.78
115.8
120.8
120.4
7.15
7.31
130.3
-282.9
129.2
137.4
N
N
H
H
6.90
114.3
7.09
115.2
H
9.70
H
H
FIGURE 2 Selected 1H,13C-HMBC () and 1H,15N-HMBC () correlations facilitating structural elucidation
of 5Ab (left) and 1H, 13C and 15N chemical shifts (right).
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FIGURE 3 2D NOESY spectrum showing key cross peaks for determining relative stereochemistry at C-4 and
C-5 of 4Ab in CDCl3.
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FIGURE 4 Molecular structures of 2A (left) and 4Ab (right) with thermal ellipsoids shown at 50% probability.
Cg1, Cg2 and Cg3 represent centroids of individual rings of acridine moiety.
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