One-pot synthesis of 1,2,3-triazole derivatives of maleopimaric and dihydroquinopimaric acids

Article abstract of DOI:10.1134/S1070428017110161

Effective one-pot synthesis of 1,2,3-triazole derivatives of maleopimaric and dihydroquinopimaric acids consists in the reaction of diterpene propargyl esters with organic azides generated in situ in the presence of СuI catalyst.

Full text of DOI:10.1134/S1070428017110161

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2017, Vol. 53, No. 11, pp. 1701–1704. © Pleiades Publishing, Ltd., 2017.
Original Russian Text © E.V. Tret’yakova, E.V. Salimova, E.R. Shakurova, L.V. Parfenova, V.N. Odinokov, 2017, published in Zhurnal Organicheskoi Khimii,
2
017, Vol. 53, No. 11, pp. 1664–1667.
One-Pot Synthesis of 1,2,3-Triazole Derivatives
of Maleopimaric and Dihydroquinopimaric Acids
E. V. Tret’yakova,* E. V. Salimova, E. R. Shakurova, L. V. Parfenova, and V. N. Odinokov
Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, pr. Oktyabrya 141, Ufa, 450075 Russia
*
e-mail: tretyakovaelv@gmail.com
Received May 31, 2017
Abstract—Effective one-pot synthesis of 1,2,3-triazole derivatives of maleopimaric and dihydroquinopimaric
acids consists in the reaction of diterpene propargyl esters with organic azides generated in situ in the presence
of СuI catalyst.
DOI: 10.1134/S1070428017110161
Diene adducts of levopimaric acid and products of
[21–24] we performed the functionalization of
diterpene terminal alkynes in the conditions of reaction
of 1,3-dipolar cycloaddition and carried out the
synthesis of 1,2,3-triazole derivatives of maleopimaric
and dihydroquinopimaric acids.
their further transformations are accessible objects for
chemical modification [1–3], applied as synthetic
platform for development of pharmacologically active
compounds [4]. Maleopimaric and dihydroquino-
pimaric acids are products of the reaction of
levopimaric acid with maleic anhydride and
p-benzoquinone, and their derivatives possess also
antiphlogistic [5], antiviral [6], antitumor [7] properties
and may be considered as promising agents for
preventing and treating gastric ulcer [8].
Initial diterpene terminal alkynes 1 and 2 were
obtained by the reaction of maleopimaric and
dihydroquinopimaric acids chlorides with propargyl
alcohol in anhydrous chloroform at room temperature
[24]. The one-pot synthesis of 1,2,3-triazole
derivatives of diterpenoids 3–6 was performed in two
steps. First the reaction of equimolar amounts of
benzyl or hexyl bromide, triethylamine, and sodium
azide at room temperature in aqueous solution of 1-
Introduction of 1,2,3-triazole fragment into a mole-
cule of diterpenoids is promising because of a wide spec-
trum of biological activity of compounds, containing this
substituent [9, 10]. For compounds of this class anti-
viral [11], antibacterial [12], antitumor [13], antiphlo-
gistic [14] activity is typical, as well as the ability of
selective inhibition of HIV-1 protease [15] and tyrosine
kinase [16].
butanol (H O‒BuOH, 1 : 1) resulted in the formation
2
of the corresponding organic azide that was without
isolation brought into the reaction with propargyl ester
of maleopimaric acid 1 or dihydroquinopimaric acid 2
in the presence of CuI as catalyst. As a result we
obtained 1,2,3-triazole derivatives of maleopimaric (3
and 4) and dihydroquinopimaric (5 and 6) acids in 80–
One of the most significant synthetic methods of
building up five-membered heterocyclic systems is a
,3-dipolar cycloaddition, where azide-alkyne
cycloaddition (CuAAC) catalyzed by cooper salts (I),
with generation of 1,4-disubstituted 1,2,3-triazoles
may serve as a classic example [17]. Alkynes are
accessible [18], while the preparation of azido
derivatives is problematic due to their instability [19],
and the exclusion of the stage of azides isolation
significantly simplifies the synthesis of triazoles [20].
8
9% yields respectively (Scheme 1).
1
1
In H NMR spectra of compounds 3–6 signals of
protons of the acetylene group are absent, and
broadened signals were observed of the proton of
triazole ring at 7.60–7.61 ppm that in the HSQC and
HMBC spectra was correlated with the signals of
2'
3'
atoms С and С of heterocycle in the region 143.44‒
13
1
46.80 and 123.54‒123.71 ppm. In C NMR spectra
In continuation of research on synthetic
transformations of diene adducts of levopimaric acid
of compounds 3 and 5 with benzyl residue resonance
peaks were present from the carbon atoms of the
1
701

1
702
TRET’YAKOVA et al.
Scheme 1.
O
O
H
H
1
9
1
8
O
O
1
0
7
H
1
2
1
1
2
13
15 23
16
9
1. NaN3 ,E t N, t-BuOH
2
4
3
1
4
BrR
1
+
H
O
o
2
3
10
8
7
2. CuI, 20 C
2
1
H
H
O
4'
5
6
3'
R
H
O
1'
N
4
2
'
H
O
O
N
O
22
N
1
3, 4
1
7
O
O
1
6
H
H
H
1
5
12
1
1
8 11 13
12a
4a
2
1
. NaN ,Et N, t-BuOH
3 3
1
0
10b
3
1
4
+
BrR
4
o
2
. CuI, 20 C
9
8
10a
6b
4b
1
9
H
5
H
H
O
O
6
4
'
7
3
'
R
H
H
1
'
2
'
N
N
2
0
O
O
O
O
2
5,6
N
6
R = Bn (3, 5), C H13 (4, 6).
1
aromatic ring in the region 128.07‒135.46 ppm, in H
NMR spectra the signals of aromatic protons were
observed at 7.21‒7.40 ppm. For hexyl-substituted
compounds 4 and 6 the signals of protons of methylene
groups were registered in the region 1.21–1.78, 1.95–
sulfuric acid with subsequent heating at 100‒120°С
during 2‒3 min. For column chromatography neutral
Al O was used (KhromLab, Russia). Propargyl esters
2
3
of maleopimaric and dihydroquinopimaric acids 1 and
2 were synthesized by method [24].
2
.00, and 5.10–5.30 ppm, the signals of protons of
Compounds 3–6. General method. A mixture of
.7 mL (1 mmol) of triethylamine, 0.07 g (1 mmol) of
methyl group appeared as a broadened signal at
0
0
.85 ppm.
sodium azide, and 0.25 mL (1 mmol) of benzyl
bromide or 0.19 mL (1 mmol) of hexyl bromide in 5 mL
of water and 5 mL of 1-butanol was intensively stirred
for 30 min at room temperature. To the mixture were
added 0.44 g (0.5 mmol) of propargyl ester of maleo-
pimaric acid 1 or 0.45 g (0.5 mmol) of propargyl ester
of dihydroquinopimaric acid 2 in 5 mL of 1-butanol
and 0.013 g of cooper(I) iodide, and the reaction
mixture was stirred for 12 h at room temperature (TLC
monitoring). The reaction mixture was poured into 50 mL
of water, the reaction products were extracted with
chloroform (2 × 50 mL), the extract was washed with
Simple and convenient one-pot synthesis of new
,2,3-triazole derivatives of diene adducts of
1
levopimaric acid from alkyl- or aryl halides, sodium
azide, and diterpene terminal acetylenes with copper
iodide as catalyst proceeds in mild conditions and
includes the formation in situ of azides that allows
excluding the isolation of unstable organic azides.
EXPERIMENTAL
1
3
1
С and Н NMR spectra were registered on a pulse
water till neutral washings, dried with CaCl . Solvent
2
spectrometer Bruker Avance III (500.13 and 125.47 МHz
respectively), internal reference tetramethylsilane.
Melting points were determined on a Boëtius
apparatus. For TLC Sorbfil plates were used
was evaporated, the precipitate was chromatographed
on a column packed with Al O eluting with methylene
2
3
chloride.
(
1
Sorbpolymer, Russia), eluent hexane‒ethyl acetate,
: 1. Spots were visualized by 10% solution of
(1-Benzyl-1H-1,2,3-triazol-4-yl)methyl 13-iso-
propyl-4,10-dimethyl-2,24-dioxotetradecahydro-1H-
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 53 No. 11 2017

ONE-POT SYNTHESIS OF 1,2,3-TRIAZOLE DERIVATIVES OF MALEOPIMARIC
1703
1
9
5а,е
6b
8а,е
9а,е
8
,12-ethenophenanthro[1,2-c]furan-4-carbo-xylate
(3H, Н ), 1.20‒1.65 m (12Н, Н , Н , Н , Н
,
1
10а,е
10b
11а,е
4а
15
(
3). Yield 0.39 g (89%), mp 102‒104°C. Н NMR
Н
, Н , Н ), 2.14 s (1Н, Н ), 2.33 t (1H, H , J
6.2 Hz), 2.40–2.50 m (4Н, Н , Н ), 2.75 br.s (1Н, Н ),
2
0
2
3
1а
spectrum (СDCl ), δ, ppm: 0.60 s (3H, Н ), 0.65‒0.90
m (5Н, Н , Н , Н ), 1.00 d (3H, Н , J 6.9 Hz),
1
Н
Н , J 8.4 Hz), 2.40 d.t (1H, Н , J 3.0, 14.0 Hz), 2.70
d (1H, Н , J 8.4 Hz), 3.08 d (1H, Н , J 8.4 Hz), 4.30
br.s (2H, H ), 5.10–5.30 m (2H, H ), 5.50 s (1Н, Н ),
7
3
2а,е
1
а
3а,е
18
12
1'
3.12 br.s (1Н, Н ), 4.25 br.s (2H, H ), 5.15–5.22 m
1
9
1е
5
4')
14
.15 d (3H, Н , J 7.0 Hz), 1.21–1.81 m (9Н, Н , Н ,
(2H, H , 5.55 s (1Н, Н ), 7.18–7.36 m (5Harom), 7.60
6
1
а,е
7a,e
9
11а,е
21
3' 13
, H , H , Н ), 1.30 s (3H, Н ), 2.25 d (1H,
s (1H, H ). С NMR spectrum (СDCl ), δ, ppm: 15.90
(С ), 16.60 (С ), 17.18 (С ), 20.01 (С ), 20.55 (С ),
21.27 (С ), 27.88 (С ), 32.89 (С ), 34.75 (С ), 36.70
(С ), 37.14 (С ), 37.88 (С ), 38.11 (С ), 38.18 (С ),
39.87 (C ), 41.28 (С ), 46.77 (С ), 50.55 (С ), 54.85
(С ), 55.11 (C ), 55.85 (С ), 57.77 (C ), 60.55 (С ),
124.11 (C ), 125.47 (C ), 127.00 (Carom), 127.11
(Carom), 127.14 (Carom), 128.02 (C ), 134.00 (C ),
135.16 (C ), 146.84 (C ), 149.11 (C ), 178.59 (C ),
3
7
16
19
18
9
17
16
1
5
12
6
11
15
3
1
'
4'
14
5
8
12
10
10a
3
'
13
4b
2
7
6а
.21–7.40 m (5Harom), 7.61 s (1H, H ). С NMR
2
0
19
10b
4'
4а
1'
1а
spectrum (СDCl ), δ, ppm: 15.49 (С ), 16.70 (С ),
1
3
2
18
19
6
3'
14
6.94 (С ), 20.00 (С ), 20.58 (С ), 21.52 (С ), 29.74
11
17
7
12
3
(
С ), 32.77 (С ), 34.61 (С ), 35.64 (С ), 36.42 (С ),
arom
arom
20
1
0
1
8
15
2'
13
3
7.58 (С ), 37.86 (С ), 40.33 (С ), 45.63 (С ), 46.95
arom
1
4
5
16
9
4'
4
(
С ), 49.19 (С ), 53.00 (С ), 54.06 (С ), 54.71 (C ),
207.21 (C ), 209.00 (C ). Found, %: C 74.00; H 7.90;
N 7.00. C H N O . Calculated, %: C 74.07; H 7.77;
N 7.20.
1
'
3'
14
5
1
7.70 (C ) 123.71 (C ), 125.14 (C ), 128.07 (Carom),
36
45
3
4
28.22 (Carom), 128.84 (Carom), 129.14 (C ), 134.70
arom
2
'
13
(
Carom), 135.46 (C ), 143.44 (C ), 148.06 (C ),
arom
2
3
24
22
1
7
7
71.18 (C ), 172.90 (C ), 178.27 (C ). Found, %: C
1.00; H 7.54; N 7.00. C H N O . Calculated, %: C
(1-Hexyl-1H-1,2,3-triazol-4-yl)methyl 13-iso-
propyl-7,10a-dimethyl-1,4-dioxohexadecahydro-1H-
4b,12-ethenochrysene-7-carboxylate (6). Yield 0.36
g (80%), mp 113‒115°C. Н NMR spectrum (СDCl ),
δ, ppm: 0.57 s (3H, Н ), 0.65‒0.80 m (2H, Н ), 0.85
34
41
3
5
1.43; H 7.23; N 7.35.
1-Hexyl-1H-1,2,3-triazol-4-yl)methyl 13-iso-
propyl-4,10-dimethyl-23,24-dioxotetradecahydro-
H-8,12-ethenophenanthro[1,2-c]furan-4-carbo-
1
3
(
1
8
6a,e
9
'
16
17
s (3Н, Н ), 1.02 d (3H, Н , J 6.9 Hz), 1.05 d (3H, Н ,
1
1
9
5а,е
1
J 6.9 Hz), 1.18 s (3H, Н ), 1.20‒1.66 m (12Н, Н
,
xylate (4). Yield 0.36 g (83%), mp 108–110°C. Н
NMR spectrum (СDCl ), δ, ppm: 0.60 s (3H, Н ),
0
Н , J 7.0 Hz), 1.20 s (3H, Н ), 1.21–1.78 m (20Н,
Н
Н ), 1.95 br.s (2Н, H ), 2.25 d (1H, Н , J 8.4 Hz),
2
8
5
6
b
8а,е
9а,е
10а,е
10b
11а,е
2
0
Н , Н , Н , Н , Н , Н ), 1.70–1.88 m (6Н,
3
6
'
7'
8'
5'
4а
9
'
18
H , H , Н ), 2.00 br.s (2Н, H ), 2.20 s (1Н, Н ), 2.40
t (1H, H , J 6.2 Hz), 2.50‒2.62 m (4Н, Н , Н ), 2.78
br.s (1Н, Н ), 3.22 br.s (1Н, Н ), 4.42 br.s (2H, H ),
.20‒5.35 m (2H, H ), 5.54 s (1Н, Н ), 7.77 s (1H,
H ). С NMR spectrum (СDCl ), δ, ppm: 13.94 (С ),
5.88 (С ), 16.70 (С ), 16.98
0.53 (С ), 21.23 (С ), 22.42 (C ), 26.00 (C ), 27.75
С ), 29.84 (C ), 31.11 (C ), 32.89 (С ), 34.66 (С ),
6.76 (С ), 36.99 (С ), 37.88 (С ), 38.12 (С ), 38.16
(С ), 38.98 (C ), 41.22 (С ), 46.72 (С ), 49.92 (С ),
50.98 (C ), 54.85 (С ), 55.85 (С ), 60.58 (С ),
57.80 (C ), 125.54 (C ), 126.92 (C ), 146.80 (C ),
148.25 (C ), 178.55 (C ), 208.01 (C ), 209.16 (C ).
Found, %: C 73.02; H 9.14; N 7.50. C35
Calculated, %: C 72.75; H 8.99; N 7.27.
.85 s (3Н, Н ), 1.05 d (3H, Н , J 6.9 Hz), 1.10 d (3H,
1
5
2
3
1
9
21
1
а
12
1'
1
8
а,e
2а,е
3а,е
5
6а,е
7a,e
9
11а,е
6'
7'
, Н , Н , Н , Н , H , H , Н , H , H ,
4
'
14
'
5'
17
5
3
'
13
9'
1
6
15
.40 d.t (1H, Н , J 3.0, 14.0 Hz), 2.75 d (1H, Н , J
3
1
9
18
9
17
1
2
1'
1
2
(
(С ), 19.89 (С ),
.4 Hz), 3.10 d (1H, Н , J 8.4 Hz), 4.40 br.s (2H, H ),
.20–5.35 m (2H, H ), 5.50 s (1Н, Н ), 7.60 s (1H,
1
6
6
8'
7'
4
'
14
1
1
6'
5'
15
3
3
'
13
9'
H ). С NMR spectrum (СDCl ), δ, ppm: 13.94 (С ),
1
3
5
8
12
10
2
0
19
2
18
3
5.49 (С ), 16.75 (С ), 16.93 (С ), 19.94 (С ), 20.56
1
9
6
8'
7'
11
10a
4b
2
7
6а
(
С ), 21.63 (С ), 22.42 (C ), 26.00 (C ), 27.21 (С ),
6
'
5'
17
7
4'
10b
4а
1а
2
9.84 (C ), 31.11 (C ), 32.74 (С ), 34.69 (С ), 35.66
1
2
3
10
1
8
1'
3'
14
2'
(
С ), 36.49 (С ), 37.66 (С ), 37.88 (С ), 40.40 (С ),
15
4
5
4'
13
20
1
4
4
5.63 (С ), 47.24 (С ), 49.27 (С ), 50.98 (C ), 53.04
1
6
9
1'
3'
(
(
(
С ), 53.13 (С ), 57.80 (C ), 123.54 (C ), 125.17
C ), 146.80 (C ), 148.13 (C ), 170.94 (C ), 172.75
C ), 178.09 (C ). Found, %: C 70.00; H 8.14; N
H N O .
51 3 4
1
4
2'
13
23
2
4
22
7
7
.55. C H N O . Calculated, %: C 70.06; H 8.37; N
33 47 3 5
ACKNOWLEDGMENTS
.43.
1-Benzyl-1H-1,2,3-triazol-4-yl)methyl 13-iso-
propyl-7,10a-dimethyl-1,4-dioxohexadecahydro-1H-
b,12-ethenochrysene-7-carboxylate (5). Yield 0.39 g
Structural investigations of compounds 3–6 were
performed in the Center of joint usage “Agidel” at the
Institute of Petrochemistry and Catalysis of the
Russian Academy of Sciences. Study was performed
under the financial support of the Russian Science
Foundation (grant no. 16-13-10051).
(
4
1
(87%), mp 98‒100°C. Н NMR spectrum (СDCl ), δ,
3
1
8
6a,e
ppm: 0.55 s (3H, Н ), 0.75‒0.89 m (2H, Н ), 1.00 d
1
6
17
(
3H, Н , J 6.9 Hz), 1.02 d (3H, Н , J 6.9 Hz), 1.15 s
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 53 No. 11 2017

1
704
TRET’YAKOVA et al.
11. Jordào, A.K., Afonso, P.P., Ferreira, V.F.,
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