Letter - spectral assignment
Received: 9 July 2015
Revised: 10 September 2015
Accepted: 16 September 2015
Published online in Wiley Online Library: 19 October 2015
(wileyonlinelibrary.com) DOI 10.1002/mrc.4368
1
13
H and C NMR spectral assignments of
novel naphthalenylphenylpyrazolines
Yearam Jung,a† Seunghyun Ahn,a† Hyeryoung Jung,a Dongsoo Kohb**
and Yoongho Lima*
approximately 50 mM, for the NMR experiments. All NMR experi-
Introduction
ments were performed on an Avance 400 spectrometer (9.4 T;
Bruker, Karlsruhe, Germany) at 25 °C. For the 1H NMR experiments,
Compounds containing pyrazolinyl-1-carbothioamide scaffolds
(Fig. 1A) can act as anticancer agents, antimicrobial agents, and
monoamine oxidase inhibitors.[1–4] When ethyl 2-bromoacetate is
added to pyrazolinyl-1-carbothioamide, 2-pyrazolin-1-ylthiazol-
4(5H)-one (Fig. 1B) is produced.[5] Compounds containing
thiazolone scaffolds show hepatitis C virus inhibitory effects, antitu-
bercular, antibacterial, and antimicrobial activities.[6–8] We designed
naphthalenylphenylpyrazolinyl-1-carbothioamides (Fig. 1C) and
naphthalenylphenyl-2-pyrazolin-1-ylthiazol-4(5H)-ones (Fig. 1D). Five
thousand compounds containing pyrazolinyl-1-carbothioamide scaf-
folds and three thousand compounds containing 2-pyrazolin-1-
ylthiazol-4(5H)-one scaffolds have been reported. Similar to chalcones
(Fig. 1E), naphthalenylphenylpyrazolinyl-1-carbothioamides and
naphthalenylphenyl-2-pyrazolin-1-ylthiazol-4(5H)-ones contain a C6-
C3-C6 skeleton. Chalcones are a group of plant-derived polyphenols.
Because of their diverse biological activities, chalcones are still being
derivatized.[9–12] Therefore, the NMR and mass spectrometric (MS)
data of the compounds we have designed and synthesized could
help us identify newly synthesized derivatives or derivatives isolated
from natural sources in the future. We report herein the complete
1H and 13C NMR data and high resolution MS data of 13 novel
naphthalenylphenylpyrazolinyl-1-carbothioamides and five novel
naphthalenylphenylpyrazolinyl-1-thiazol-4(5H)-ones.
the relaxation delay, 90 ° pulse, spectral width, number of data
points, and digital resolution were set to 1 s, 11.8 μs, 5555 Hz,
32K, and 0.339 Hz/point, respectively. For the 13C NMR experi-
ments, the same parameters were set to 3 s, 15.0μs, 20 964 Hz,
64K, and 0.640Hz/point, respectively. For correlation spectroscopy
(COSY), heteronuclear multiple quantum coherence (HMQC), and
heteronuclear multiple bond connectivity (HMBC), the data points
were set to 2 K × 256 (t2 × t1). The long-range coupling time for
HMBC was set to 40 and 70 ms. The chemical shifts were referenced
to TMS. Prior to Fourier transformation, the two-dimensional NMR
data were processed with zero filling of 2 K and the sine-squared
bell window function using XWin-NMR (Bruker, Karlsruhe,
Germany).[16] All NMR data were analyzed using Sparky.[17]
General experimental procedures
To obtain the high-resolution MS data of the naphthalenylphenyl
pyrazoline derivatives, ultraperformance liquid chromatography-
hybrid quadrupole-time-of-flight mass spectrometry was carried out
on a Waters Acquity ultraperformance liquid chromatography system
(WatersCorp.,Milford,MA,USA)withthehelpofProfessorChoongHwan
LeeatKonkukUniversity,Korea.[18]AllmassdatawereM + Hions.
Experimental
Results and discussion
Syntheses
All of the synthesized naphthalenylphenylpyrazolines are listed
in Table 1. The procedure used to assign the NMR data of
derivative 1, 3-(1-hydroxynaphthalen-2-yl)-5-(2-methoxyphenyl)-
4,5-dihydropyrazole-1-carbothioamide was as follows: The 13C peak
indicating a deshielding appeared at 178.8 ppm and was assigned
1-Hydroxynaphthylchalcone (I), which was prepared via previously
reported methods, was treated with thiosemicarbazide to give
thioamide compounds (1–3).[13] The same procedures were applied
to 2-hydroxynaphthylchalcone (II) to produce the corresponding
thioamide compounds (4-7), which were reacted with ethyl
bromoacetate to give thiazolone compounds (14–18).[14]
Benzochalcone (III) was reacted with hydrazine to form pyrazoline
(IV); then, IV was dissolved in ethanol and treated with an equimo-
lar amount of methoxy-substituted isothiocyanate, and the
resulting solution was refluxed.[15] The reaction mixture was cooled
to room temperature to form a solid, which was recrystallized in
ethanol to produce the pure pyrazole-1-carbothioamide com-
pound. The synthetic process is summarized in Scheme 1.
*
Correspondence to: Yoongho Lim, College of Bioscience and Biotechnology, BMIC,
Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea. E-mail:
** Correspondence to: Dongsoo Koh, Department of Applied Chemistry, College of
Natural Sciences, Dongduk Women’s University, Seoul 136-714, Korea. E-mail:
†
Y. Jung and S. Ahn contributed equally to this work.
a College of Bioscience and Biotechnology, BMIC, Konkuk University, Seoul 05029,
Korea
NMR spectra
The synthesized naphthalenylphenylpyrazolines were prepared in
deuterated dimethyl sulfoxide (DMSO-d6), with concentrations of
b Department of Applied Chemistry, College of Natural Sciences, Dongduk Women’s
University, Seoul 136–714, Korea
Magn. Reson. Chem. 2016, 54, 252–259
Copyright © 2015 John Wiley & Sons, Ltd.
Jung, Yearam
