Table 4 Vibrational frequencies (harmonic approximation) of the O–H bonds in the muchimangin B molecule
Conformer
Vibrational frequencies
O16−H23
O18−H25
O20−H26
O22−H28
1-a
3,563.57
3,178.20
a
3,178.20
a
3,575.97
3,125.44
b
3,125.44
b
1-b
3,565.50
3,171.05
a
3,171.05
a
3,575.13
3,126.40
b
3,126.40
b
1-c
3,565.60
3,166.40
a
3,166.40
a
3,574.76
3,116.98
b
3,116.98
b
1-e
3,563.93
3,167.91
a
3,167.91
a
3,574.50
3,120.28
b
3,120.28
b
1-f
3,560.61
3,170.09
a
3,170.09
a
3,574.93
3,116.91
b
3,116.91
b
2-a
3,400.16
3,218.00
a
3,218.00
a
3,574.73
3,128.23
b
3,128.23
b
1-g
3,555.22
3,176.18
a
3,176.18
a
3,576.02
3,132.22
b
3,132.22
b
1-h
3,562.12
3,173.64
a
3,173.64
a
3,573.5
3,128.04
b
3,128.04
b
1-i
3,552.34
3,176.70
a
3,176.70
a
3,574.13
3,133.32
b
3,133.32
b
2-b
3,588.72
3,209.91
a
3,209.91
3,575.37
3,131.56
b
3,131.56
b
3-a
3,563.20
3,219.62
a
3,219.62
a
3,687.05
3,126.31
b
3,126.31
b
3-b
3,564.80
3,207.07
a
3,207.07
a
3,687.56
3,130.72
b
3,130.72
b
3-c
3,565.28
3,209.29
a
3,209.29
a
3,686.23
3,120.08
b
3,120.08
b
5-a
3,565.53
2,942.08
3,606.83
3,626.37
5-b
3,566.92
2,954.10
3,606.27
3,625.38
6-b
3,619.97
3,607.98
2,950.89
3,576.63
6-a
3,620.62
3,607.65
2,973.13
3,577.79
5-c
3,567.63
2,930.72
3,607.10
3,625.30
6-c
3,621.91
3,607.44
2,949.33
3,575.95
8
3,589.34
3,027.12
3,605.79
3,626.07
9-b
3,618.82
3,608.18
3,019.10
3,688.67
10
3,406.23
3,561.38
3,604.93
3,626.06
11-a
3,621.74
3,605.86
3,604.63
3,627.26
11-b
3,620.54
3,605.91
3,604.41
3,626.48
11-c
3,623.20
3,605.11
c
3,605.11
c
3,626.62
3,604.92
d
3,604.92
d
DFT/B3LYP/6-31+G(d,p) results in vacuo. The frequency values have been scaled by the factor 0.964,
recommended for DFT/B3LYP/6-31+G(d,p) calculations [24]
a H25 and H26 moving symmetrically toward O19 and away from it
b H25 and H26 moving asymmetrically toward O19 and away from it (when one approaches, the other
moves away)
c H25 and H26 moving symmetrically toward O17 and O21 respectively
d H25 and H26 moving asymmetrically toward O17 and O21 respectively
102
L. Mammino et al.