Table 3 Parameters of the intramolecular hydrogen bonds in the calculated conformers of
muchimangin B, in vacuo
Conformer
IHB
considered
Parameters of the IHB
HF/6-31G(d,p) results
DFT/B3LYP/6-31+G(d,p)
results
H⋯O
(Å)
O⋯O
(Å)
OĤO
H⋯O
(Å)
O⋯O
(Å)
OĤO
1-a
H23⋯O17
2.087
2.636
115.3
2.034
2.633
117.8
H25⋯O19
1.787
2.617
143.5
1.673
2.576
148.7
H26⋯O19
1.805
2.635
143.5
1.692
2.592
148.5
H28⋯O21
2.139
2.669
114.0
2.082
2.663
116.4
1-b
H23⋯O17
2.083
2.633
115.5
2.036
2.634
117.7
H25⋯O19
1.791
2.620
143.4
1.675
2.576
148.6
H26⋯O19
1.801
2.632
143.6
1.685
2.587
148.7
H28⋯O21
2.141
2.670
114.0
2.082
2.663
116.4
1-c
H23⋯O17
2.093
2.637
115.0
2.036
2.633
117.6
H25⋯O19
1.781
2.612
143.6
1.667
2.571
148.9
H26⋯O19
1.802
2.633
143.6
1.688
2.590
148.7
H28⋯O21
2.135
2.667
114.2
2.079
2.661
116.6
1-d
H23⋯O17
2.084
2.634
115.4
2.030
2.631
117.9
H25⋯O19
1.780
2.612
143.6
1.666
2.570
148.9
H26⋯O19
1.803
2.634
143.6
1.688
2.590
148.7
H28⋯O21
2.136
2.668
114.2
2.078
2.660
116.6
1-e
H23⋯O17
2.088
2.636
115.3
2.036
2.634
117.6
H25⋯O19
1.781
2.612
143.6
1.669
2.572
148.7
H26⋯O19
1.802
2.633
143.6
1.688
2.589
148.7
H28⋯O21
2.136
2.667
114.1
2.079
2.661
116.5
1-f
H23⋯O17
2.084
2.634
115.4
2.027
2.629
118.0
H25⋯O19
1.780
2.611
143.6
1.666
2.570
148.9
H26⋯O19
1.803
2.634
143.6
1.690
2.591
148.6
H28⋯O21
2.137
2.667
114.2
2.080
2.662
116.5
2-a
H23⋯O41
1.807
2.726
162.0
1.736
2.688
162.9
H25⋯O19
1.801
2.629
143.4
1.699
2.594
148.1
H26⋯O19
1.799
2.630
143.6
1.681
2.584
148.8
H28⋯O21
2.140
2.669
113.9
2.082
2.662
116.4
1-g
H23⋯O17
2.062
2.617
115.8
2.006
2.616
118.6
H25⋯O19
1.794
2.624
143.5
1.682
2.583
148.6
H26⋯O19
1.802
2.633
143.6
1.688
2.590
148.7
H28⋯O21
2.140
2.669
114.0
2.083
2.663
116.4
1-h
H23⋯O17
2.081
2.632
115.5
2.032
2.632
117.8
H25⋯O19
1.787
2.617
143.5
1.675
2.577
148.6
H26⋯O19
1.805
2.635
143.5
1.689
2.590
148.6
H28⋯O21
2.135
2.667
114.2
2.080
2.661
116.5
(continued)
Ab-Initio and DFT Study of the Muchimangin-B Molecule
99