Thesis-Final 03 June 2011 pdf - Jacobs University

Results and discussion Chapter 3
The 13 C-NMR shows consistent signals with 1 H-NMR spectrum. The first signal at
21.26 ppm assigned to acetyl carbon C-27. The two CH 2 carbons were found at 36.46
and 36.51 ppm. The signal at 36.46 ppm assigned to C-2 and the other signal at 36.51
ppm assigned to C-6. The three protons of quinide were appeared at 64.21, 68.79 and
72.12 ppm. Due to crosspeaks at HMQC spectrum these peaks were assigned to C-4,
C-3 and C-5 carbons. The typical carbon atom of quinide which is next to carbonyl
group was found at 76.12 ppm and assigned to C-1. The four pear of C=CH protons
were found at 116.75, 117.46, 145.88 and 146.62 ppm. The first two pear assigned to
C-9 and C-18 due to crosspeaks at 1 H 1 H-COSY spectrum then the other pear at
145.88 and 146.62 ppm assigned to C-10 and C-19. The eight carbons of aromatic
groups which has hydrogen attached to it were found around 122.30, 128.33, 128.93,
129.04, 129.09, 129.58, 130.80 and 130.90 ppm. The other two carbons with small
intensity at 131.87 and 134.01 ppm assigned to single carbon atoms of aromatic group
C-11 and C-20. The two signals at 152.49 and 165.43 ppm identified as C-23 and C-8
which are adjacent to oxygen atoms. The last set of peaks at 165.43, 169.24, 171.30
and 177.55 ppm assigned to C-8, C-17, C-26 and C-7 carbons respectively due to
chemical shifts. The infrared spectrum shows strong signals for the two carbonyl
esters at 1765 cm -1 and 1684 cm -1 . Also strong signal at 1633 cm -1 for the aromatic
groups as it was expected.
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F1 Chemical Shift (ppm)
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8.5 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0
F2 Chemical Shift (ppm)
Figure 113 : 1 H 13 C-HMQC spectrum of (1S,3R,4R,5R)-1-cinnamoyl-3-(acetyl p-
coumaroyl) quinide
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