Download - NMR spectroscopy
Spectroscopy Analysis of Natural
Products-1
21.01.2014 EFG-704
By Omer Bayazeid
Introduction:
Origanum vulgare (Lamiaceae) is a perennial herb distributed in Europe,NorthAfrica,America and Asia.
The herb is widely used as a spice in Western diets, and is also commonly used as a traditional medicine for the treatment of various diseases, such as cold, cough, and digestive disorders.
The plant is known for its powerful antimicrobial and antioxidant activities.
The antimicrobial activity of O. vulgare is due to its high content of volatile oils.
The phenolic compounds including flavonoids and phenolic acids, another kind of constituent in O. vulgare, are responsible for its antioxidant activity.
In their work, they report the isolation of six new phenolic compounds (1–6) from O. vulgare, along with known ones:2,5-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, rosmarinic acid, origanoside.
The structures of the new compounds were identified with spectroscopic analyses and acid hydrolysis experiments.
Plant material:
Whole plants of O. vulgare were collected in China, in September 2012.
Extraction and isolation:
The air-dried whole plants of O. vulgare (10.0 kg) were powdered and percolated with 95% (V/V) ethanol solution at room temperature. For Isolation Column chromatography and TLC was performed using precoated silica gel GF254 plates.
Identification of Compounds:
Compound-1:
4-[[(2’,5’-dihydroxybenzoy- l)oxy]methyl] phenyl-O-b-D-glucopyranoside
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1 Cq 157.3 -
2,6 CH 116.3 7.05 (d,8.6)
3,5 CH 129.7 7.37 (d,8.4)
4 Cq 129.8 -
7 CH2 065.4 5.16 (s)
Ring A
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’ Cq 120.6 -
2’ Cq 150.6 -
3’ CH 115.5 6.81 (d, 8.3)
4’ CH 122.0 7.34 (dd, 8.3,2.1)
5’ Cq 145.1 -
6’ CH 116.3 7.38 (d, 2.1)
7’ Cq 165.6 -
Ring B
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’’ CH 100.4 4.89 (d,7.4)
2’’’ CH 73.3 3.26 (m)
3’’’ CH 76.7 3.34 (m)
4’’’ CH 69.8 3.18 (m)
5’’’ CH 77.1 3.27 (m)6’’’ CH2 60.8 3.70(m)
3.74(m)
Sugar Part
D-glucose
HMBC
The NMR data of ring B were identical to those of 2,5-dihydroxy- benzoic acid ,suggesting ring B had two hydroxyls at C-2’ and C-5’ positions, respectively. It was also confirmed by the 1H–1H COSY and HMBC correlations
Identification of Compounds:
Compound-2:
4-[[(3’,4’-dihydroxybenzoyl)oxy]methyl]phenyl-O-B-D-[6-O-(3’’,5’’-dimethoxyl-4’’-hydrox- ybenzoyl)] glucopyranoside
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1 Cq 159.0 -
2,6 CH 117.9 7.03 (d,8.6)
3,5 CH 130.7 7.18 (d,8.6)
4 Cq 132.0 -
7 CH2 067.1 5.16 (s)
Ring A
Carbon No.
Type of
Carbon
13C Signal
δ/ppm
1H signalδ/ppm
1’ Cq 122.9 -
2’ CH 117.6 7.47 (d)
3’ Cq 146.3 -
4’ Cq 152.0 -
5’ CH 116.1 6.85 (d, 8.0)
6’ CH 123.9 7.48 (dd, 8.0,2.4)
7’ Cq 168.3 -
Ring B
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’ Cq 121.5 -
2’’,6’’
CH 108.7 7.33 (s)
3’’,5’’
Cq 149.1 -
4’’ Cq 142.4 -
7’’ Cq 168.0 -
3’’,5’-OMe
CH3 057.1 3.83 (s)
Ring C
Sugar Part Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’’ CH 102.3 4.93 (d,7.4)
2’’’ CH 75.0 3.81 (m)
3’’’ CH 78.1 3.51 (m)
4’’’ CH 72.3 3.51 (m)
5’’’ CH 75.8 3.79 (m)
6’’’ CH2 65.4 4.73 (m) 4.42 (m)
D-glucose
HMBC
The HMBC correlations between δH 4.73 (H-6’’’) and δC 168 (C-7’’) suggested the benzoyl was connected to C-6’’’ through an ester bond.
The positions of methoxy groups were elucidated by the HMBC correlations.
Identification of Compound:
Compound-3:
acacetin 7-O-[4’’’O-acetyl-b-D-apiofuransyl-(1 -3)]- b-D-xylopyranoside
Ring ACarbon No.
Type of Carbon
13C Signal
δ/ppm
1H signalδ/ppm
2 Cq 163.8 -
3 CH 103.8 6.95 (s)
4 Cq 182.0 -
5 CH 161.1 12.91 (s)
6 CH 099.1 6.38 (d, 2.0)
7 Cq 162.4 -
8 CH 094.4 6.81 (d, 2.0)
9 Cq 157.0 -
10 Cq 105.4 -
Carbon No.
Type of
Carbon
13C Signal
δ/ppm
1H signalδ/ppm
Ring B1’ Cq 122.6 -
2’,6’ Cq 128.4 8.08 (br d, 8.8)
3’,5’ CH 114.6 7.12 (br d, 8.8)
4’ Cq 162.5 -
4’-OMe
Cq 55.6 3.88 (s)
D-xylose
D-apiose
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’ CH 98.2 5.20 (d,7.6)
2’’ CH 75.3 3.52 (m)
3’’ CH 76.5 3.43 (m)
4’’ CH 69.4 3.41 (m)
5’’ CH2 65.7 3.76 (m)3.42 (m)
Sugar Part 1
Sugar Part 2
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’’ CH 108.2 5.38 (br s)
2’’’ CH 76.7 3.43 (m)
3’’’ Cq 77.2 -
4’’’ CH2 73.8 3.98 (m)3.73 (m)
5’’’ CH 67.0 3.92 (s)
Ac CqCH3
169.920.3
-1.82 (s)
HMBC
Identification of Compounds:
Compound-4/5:
apigenin 7-O-[6’’’- O-acetyl-b-D-galactopyranosyl-(1 -3)]-b-D-xylopyranoside.
Ring ACarbon No.
Type of Carbon
13C Signal
δ/ppm
1H signalδ/ppm
2 Cq 164.3 -
3 CH 103.1 6.95 (s)
4 Cq 182.0 -
5 CH 161.1 12.91 (s)
6 CH 099.5 6.38 (d, 2.0)
7 Cq 162.6 -
8 CH 094.7 6.81 (d, 2.0)
9 Cq 156.9 -
10 Cq 105.4 -
Carbon No.
Type of
Carbon
13C Signal
δ/ppm
1H signalδ/ppm
Ring B1’ Cq 121.0 -
2’,6’ Cq 128.6 8.08 (br d, 8.8)
3’,5’ CH 116.0 7.12 (br d, 8.8)
4’ Cq 161.4 -
4’-OMe
Cq 55.6 3.88 (s)
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’ CH 98.7 5.24 (d,7.6)
2’’ CH 75.4 3.52 (m)
3’’ CH 82.7 3.42 (m)
4’’ CH 68.8 3.41 (m)
5’’ CH2 65.6 3.76 (m)3.42 (m)
Sugar Part 1
D-xylose
Sugar Part 2
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’’ CH 104.7 4.51 (d,7.6)
2’’’ CH 74.5 3.05 (m)
3’’’ CH 75.9 3.24 (m)
4’’’ CH 69.7 3.06 (m)
5’’’ CH 73.7 3.42 (m)
6’’ CH2 63.5 3.99 (m)4.09 (m)
Ac CqCH3
170.320.3
-1.82 (s)
D-glactose
HMBC
Identification of Compound:
Compound-6:
Ring ACarbon No.
Type of Carbon
13C Signal
δ/ppm
1H signalδ/ppm
2 Cq 163.8 -
3 CH 103.1 6.95 (s)
4 Cq 182.0 -
5 CH 161.1 12.91 (s)
6 CH 099.6 6.38 (d, 2.0)
7 Cq 162.5 -
8 CH 094.9 6.80 (d, 2.0)
9 Cq 156.9 -
10 Cq 105.4 -
Carbon No.
Type of
Carbon
13C Signal
δ/ppm
1H signalδ/ppm
Ring B1’ Cq 122.7 -
2’,6’ Cq 128.4 8.08 (br d, 8.8)
3’,5’ CH 114.6 7.12 (br d, 8.8)
4’ Cq 162.9 -
4’-OMe
Cq 55.6 3.87 (s)
Sugar Part 1
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’ CH 98.3 5.24 (d,6.3)
2’’ CH 83.3 3.51 (m)
3’’ CH 75.6 3.22 (m)
4’’ CH 69.1 3.26 (m)
5’’ CH2 77.0 3.50 (m)3.42 (m)
6’’ CH2 60.5 3.73 (m)3.49 (m)
D-glucose
Sugar Part 2
Carbon No.
Type of
Carbon
13C Signal δ/ppm
1H signalδ/ppm
1’’’ CH 104.7 4.52(d, 7.6)
2’’’ CH 74.6 3.02 (m)
3’’’ CH 75.9 3.51 (m)
4’’’ CH 69.7 3.09 (m)
5’’’ CH 73.7 3.42 (m)
6’’’ CH2 63.6 3.99 (m)4.13 (m)
Ac Cq CH3
170.320.3
-1.82 (s)
D-glactose
Thank You…