Ethyl 1-(7-chloroquinolin-4-yl)-5-methyl-1H-1,2,3-triazole-4-carboxylate

Scheme 1 General scheme of the reaction. 

Scheme 2 

General procedure for the synthesis of 7-chloroquinoline-1,2,3-triazoyl carboxylates

To a solution of 4-azido-7-chloroquinoline 1 (0.3 mmol, 0.061 g) in DMSO (0.3 mL), was firstly added the β-ketoesters 2a-k (0.3 mmol) and then the catalyst pyrrolidine (0.03 mmol. 0.021 g). The reaction mixture was stirred in an open vial at room temperature for 24 hours. After completion of the reaction, the crude product was purified by column chromatography on silica gel using a mixture of hexanes/ethyl acetate (5:1) as the eluent to afford the desired products 3a-k.

Ethyl 1-(7-chloroquinolin-4-yl)-5-methyl-1H-1,2,3-triazole-4-carboxylate (3a)

Yield: 0.085 g (90%); white solid; mp 128-130 °C;
¹H NMR (CDCl₃, 300 MHz) δ 9.15 (d, 1H, J4.5 Hz, HetAr-H), 8.27 (d, 1H, J1.9 Hz, HetAr-H), 7.60 (dd, 1H, J9.0 and 1.9 Hz, HetAr-H), 7.48 (d, 1H, J4.5 Hz, HetAr-H), 7.34 (d, 1H, J9.0 Hz, HetAr-H), 4.50 (qua, 2H, J7.1 Hz, OCH₂), 2.49 (s, 3H, CH₃), 1.47 (t, 3H, J7.1 Hz, CH₃);
¹³C NMR (CDCl₃, 75 MHz) δ 161.10, 151.28, 149.88, 140.20, 139.34, 137.00, 136.76, 129.67, 128.93, 123.58, 122.09, 118.75, 61.15, 14.18, 9.44;
MS m/z (relative intensity): 316 (7), 259 (15), 243 (17), 231 (19), 217 (45), 215 (100), 214 (22), 205 (16), 203 (19), 189 (28), 181 (27), 179 (27), 164 (26), 162 (80), 137 (15), 135 (44), 127 (44), 126 (27), 100 (20), 99 (65), 83 (30), 75 (15), 74 (14), 43 (25);
HRMS calcd. for C₁₅H₁₄ClN₄O₂ [M + H]⁺: 317.0805; found: 317.0788.

Journal of the Brazilian Chemical Society

On-line version ISSN 1678-4790

J. Braz. Chem. Soc. vol.27 no.1 São Paulo Jan. 2016

http://dx.doi.org/10.5935/0103-5053.20150239

ARTICLES

7-Chloroquinoline-1,2,3-triazoyl Carboxylates: Organocatalytic Synthesis and Antioxidant Properties

Maiara T. Saraiva^a  , Roberta Krüger^a  , Rodolfo S. M. Baldinotti^b  , Eder J. Lenardão^a  , Cristiane Luchese^b  , Lucielli Savegnago^b  , Ethel A. Wilhelm^{b  *}  , Diego Alves^{a  *} 

^aLaboratório de Síntese Orgânica Limpa (LASOL, CCQFA), Universidade Federal de Pelotas (UFPel), CP 354, 96010-900 Pelotas-RS, Brazil

^bGrupo de Pesquisa em Neurobiotecnologia (GPN), CDTec/CCQFA, Universidade Federal de Pelotas (UFPel), CP 354, 96010-900 Pelotas-RS, Brazil

ABSTRACT

We describe herein our results on the synthesis and antioxidant properties of 7-chloroquinoline-1,2,3-triazoyl-4-carboxylates. This class of compounds have been synthesized in moderated to excellent yields by the reaction of 4-azido-7-chloroquinoline with a range of β-ketoesters in the presence of a catalytic amount of pyrrolidine (10 mol%). The synthesized compounds ethyl 1-(7-chloroquinolin-4-yl)-5-methyl-1H-1,2,3-triazole-4-carboxylate and ethyl 1-(7-chloroquinolin-4-yl)-5-phenyl-1H-1,2,3-triazole-4-carboxylate were screened for their in vitro antioxidant activity and the results demonstrated that the first compound reduces the lipid peroxidation levels induced by sodium nitroprusside in liver of mice, while the second compound shown nitric oxide scavenging activity. This is an efficient method to produce new heterocyclic compounds with potential antioxidant activities.
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532016000100041&lng=en&nrm=iso&tlng=en
e-mail: diego.alves@ufpel.edu.br, ethelwilhelm@yahoo.com.br

Figure 1 Biologically important quinolines. 

Key words: quinolines,  1,2,3-triazoles,  organocatalysis,  cycloaddition,  antioxidant

/////////////


Ujjain,  India

More images

Ujjain

City in India

Ujjain is the largest city in Ujjain district of the Indian state of Madhya Pradesh. It is the administrative center of Ujjain district and Ujjain division. Wikipedia

//////

Multibiphenyl A, New biphenyls from Garcinia multiflora.

Figure 2 Selected HMBC (H→C) and ¹H-¹H correlation spectroscopy (COSY) (–) correlations of 1. 

Compound 1 was obtained as a pale yellow gum. The molecular formula was determined to be C₂₀H₂₂O₆ from the molecular ion peak [M]⁺ at m/z 358.1408 in the EI-HRMS. The IR spectrum indicated that 1 possesses hydroxy (3422 cm^-1), phenyl (2939, 1498 cm^-1), and carbonyl (1721 cm^-1) functional groups. The ¹H and ¹³C NMR spectra (Table 1) revealed the signals for a 1,2,3,4,5-pentasubstituted benzene ring [d_H 6.26 (1H, s, H-6); δ_C 129.6 (C-1), 119.7 (C-2), 144.9 (C-3), 135.0 (C-4), 147.2 (C-5), 105.9 (C-6)], one p-substituted benzene ring [d_H 7.00 (2H, dd, J 8.8, 2.4 Hz, H-8, H-12), 6.74 (2H, dd, J 8.8, 2.4 Hz, H-9, H-11); δ_C 133.8 (C-7), 131.7 (C-8, C-12), 115.7 (C-9, C-11), 157.1 (C-10)], one acetoxyprenyl group [d_H 3.21 (2H, d, J 6.7 Hz, H-1'), 5.44 (1H, d, J6.7 Hz, H-2'), 4.33 (2H, s, H-4'), 1.39 (3H, s, H-5'), and 1.99 (3H, s, H-OAc); δ_C 26.8 (C-1'), 130.7 (C-2'), 134.6 (C-3'), 71.5 (C-4'), 14.0 (C-5'), 172.9, 20.8 (OAc)], and one methoxy group [d_H 3.76 (3H, s, OMe-5); δ_C 56.5 (OMe)], which implied that compound1 was a biphenyl derivative. This conclusion was confirmed by the heteronuclear multiple bond correlation (HMBC) correlations of H-6 with C-7, and of H-8 and H-12 with C-1 (Figure 2). HMBC correlations of H-1' with C-1, C-2, and C-3, and of H-2' with C-1 suggested the acetoxyprenyl group at C-2. The methoxy group was located at C-5 from the HMBC correlations of δ_H 3.76 (OMe) with C-5. Considering the signal for quarternary C-3, C-4, C-10 and the molecular formula of 1, three hydroxy groups were located at C-3, C-4, C-10, respectively. Thus, the structure of 1 was determined as shown (Figure 1), and named multibiphenyl A.

Figure 1 New biphenyls from Garcinia multiflora. 

Multibiphenyl A (1)

Pale yellow gum; [α]_D –11.0 (c 0.07, MeOH); UV (MeOH) l_max / nm (log ε) 570 (2.16), 205 (4.71); IR (KBr) n / cm^-1 3422, 2939, 1721, 1611, 1589, 1498, 1443, 1357, 1266, 1172, 1102, 1045, 1023, 838; ¹H and ¹³C NMR data (400 and 100 MHz, CD₃OD), see Table 1; ESI-MS (positive mode) m/z 381 [M + Na]⁺; EI-HRMS (M⁺) calcd.: 358.1416; found: 358.1408 (C₂₀H₂₂O₆).

Table 1 ¹H and ¹³C NMR data for compounds 1-3 (d in ppm, 1 and 2 in CD₃OD, 3 in CDC1₃, 100 and 400 MHz) 

No.	1		2		3
	δC (m) / ppm	δH (m, J , Hz) / ppm	δC (m) / ppm	δH (m, J , Hz) / ppm	δC (m) / ppm	δH (m, J , Hz) / ppm
1	129.6 s		132.4 s		132.3 s
2	119.7 s		114.2 s		112.4 s
3	144.9 s		142.0 s		141.5 s
4	135.0 s		131.9 s		132.7 s
5	147.2 s		149.6 s		144.8 s
6	105.9 d	6.26 (s, 1H )	106.6 d	6.44 (s, 1H)	105.5 d	6.43 (s, 1H)
7	133.8 s		134.6 s		132.7 s
8	131.7 d	7.00 (dd, 1H, J 8.8 Hz, 2.4)	131.8 d	7.11 (dd, 1H, J 8.4 Hz, 1.9)	130.3 d	7.16 (d, 1H, J 8.6 Hz)
9	115.7 d	6.74 (dd, 1H, J 8.8 Hz, 2.4)	116.0 d	6.82 (dd, 1H, J 8.4 Hz, 1.9)	114.8 d	6.86 (d, 1H, J 8.6 Hz)
10	157.1 s		157.7 s		155.5 s
11	115.7 d	6.74 (dd, 1H, J 8.8 Hz, 2.4)	116.0 d	6.82 (dd, 1H, J 8.4 Hz, 1.9)	114.8 d	6.86 (d, 1H, J 8.6 Hz)
12	131.7 d	7.00 (dd, 1H, J 8.8 Hz, 2.4)	131.8 d	7.11 (dd, 1H, J 8.4 Hz, 1.9)	130.3 d	7.16 (d, 1H, J 8.6 Hz)
1'	26.8 t	3.21 (d, 2H, J 6.7 Hz, CH2)	124.7 d	6.41 (d, 1H, J 10.1 Hz)	21.1 t	2.59 (t, 2H, J 6.6 Hz, CH2)
2'	130.7 d	5.44 (t, 1H, J 6.7 Hz)	124.4 d	5.48 (d, 1H, J 10.1 Hz)	33.0 t	1.72 (t, 2H, J 6.6 Hz, CH2)
3'	134.6 s		77.6 s		74.7 s
4'	71.5 t	4.33 (s, 3H, CH3)	69.0 t	4.27 (d, 1H, J 11.5 Hz, CH2)	26.7 q	1.39 (s, 3H, CH3)
				4.14 (d, 1H, J 11.5 Hz, CH2)
5'	14.0 q	1.39 (s, 3H, CH3)	23.4 q	1.47 (s, 3H, CH3)	26.7 q	1.39 (s, 3H, CH3)
3-OMe	56.5 q	3.76 (s, 3H, OCH3)	56.5 q	3.85 (s, 3H, OCH3)	56.1 q	3.86 (s, 3H, OCH3)
5'- OAc	172.9 s		172.6 s
	20.8 q	1.99 (s, 3H, COCH3)	20.7 q	2.00 (s, 3H, COCH3)

Journal of the Brazilian Chemical Society

On-line version ISSN 1678-4790

J. Braz. Chem. Soc. vol.27 no.1 São Paulo Jan. 2016

http://dx.doi.org/10.5935/0103-5053.20150235

ARTICLES

New Biphenyls from Garcinia multiflora

Xue-Mei Gao^{a  b}  , Bing-Kun Ji^{a  b}  , Yin-Ke Li^{a  c}  , Yan-Qing Ye^a  , Zhi-Yong Jiang^a  , Hai-Ying Yang^a  , Gang Du^a  , Min Zhou^a  , Xiao-Xia Pan^a  , Wen-Xing Liu^a  , Qiu-Fen Hu^{a  *} 

^aKey Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission & Ministry of Education, Kunming, P. R. China

^bJoint Research Centre for International Cross-Border Ethnic Regions Biomass Clean Utilization in Yunnan, Yunnan Minzu University, 650031 Kunming, P. R. China

^cCollege of Resource and Environment, Yuxi Normal University, 653100 Yuxi, P. R. China

ABSTRACT

Three new biphenyls were isolated from Garcinia multiflora. The structures of these biphenyls were elucidated by spectroscopic methods, and their rotavirus activity was evaluated.
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532016000100010&lng=en&nrm=iso&tlng=en
Key words: Garcinia multiflora,  biphenyls,  anti-rotavirus activity

///////

Iranian food

/////

////////