Mulliken charge population of the (2E)-IPHC molecule was
analyzed using the B3LYP method with regard to its compositional
groups: phenylpropyl, imidazole and semicarbazide. The results are
presented in Table 4. The horizontal bar diagram of comparative
Mulliken atomic charges are shown in Fig. 4. The comparison
Fig. 3. AIM molecular graph of (2E)-IPHC.
Table 3
AIM analysis for the (2E)-IPHC molecule: electron density rBCP, Laplacian of electron density D2
rBCP, electron kinetic energy density GBCP, total electron energy density HBCP and
interaction energy Eint at bond critical points (BCPs).
BCP rBCP (a.u) D2
rBCP (a.u) GBCP (a.u) HBCP (a.u) VBCP (a.u) Eint (kcal/mol)
C17eC15 0.2284 0.8328 0.1008 0.3090 0.4098 128.57
C15eC13 0.2954 0.8712 0.1034 0.3212 0.4246 133.21
C13eC11 0.2949 0.8716 0.1024 0.3204 0.4228 132.65
C11eC9 0.2946 0.8700 0.1022 0.3198 0.4220 132.40
C9eC7 0.2956 0.8724 0.1035 0.3216 0.4251 133.37
C7eC17 0.2900 0.8400 0.1015 0.3115 0.4130 129.57
C11eH12 0.2669 0.7920 0.0434 0.2413 0.2846 89.29
C17eC18 0.2471 0.6488 0.0715 0.2337 0.3052 95.75
C18eC19 0.2359 0.5896 0.0676 0.2150 0.2827 88.69
C19eC22 0.2213 0.5244 0.0595 0.1906 0.2501 78.46
N4eN5 0.2944 0.4272 0.1545 0.2613 0.4158 130.45
C31eN6 0.2972 0.6068 0.1582 0.3098 0.4680 146.83
C18eN4 0.3329 0.5596 0.2890 0.4289 0.7179 225.24
C22eN2 0.2261 0.2852 0.1194 0.1908 0.3102 97.32
C29eN2 0.2717 0.3924 0.1860 0.2741 0.4701 147.49
C29eN3 0.3276 0.7228 0.1896 0.3703 0.5600 175.70
C27eN3 0.2737 0.4648 0.1418 0.2580 0.3999 125.46
C25eN2 0.2625 0.3520 0.1809 0.2671 0.4501 141.21
C25eC27 0.3073 0.8856 0.1208 0.3422 0.4630 145.26
C31eO1 0.3700 0.5744 0.3439 0.4876 0.8315 260.88
N4/H33 0.0229 0.0936 0.0228 0.0006 0.0221 6.93
C27eH28 0.2707 0.8120 0.0422 0.2454 0.2877 90.26
C22eH24 0.2654 0.7828 0.0427 0.2383 0.2811 88.19
N.G. Haress et al. / Journal of Molecular Structure 1118 (2016) 219e232 223
between the Mulliken charge distribution in the intact (2E)-IPHC
molecule and its separated phenylpropyl moiety indicated that the
Mulliken charge distribution is almost the same in the ring and the
C17 is positive in both the (2E)-IPHC molecule and the phenylpropyl
moiety; whereas the atoms C18 and C19 exhibited some deviation
between the (2E)-IPHC molecule and the phenylpropyl moiety. This
confirms an influence of the attachment of the imidazole ring in the
(2E)-IPHC molecule. Similarly, the imidazole ring in the (2E)-IPHC
molecule displayed deviation of Mulliken charges from that of the
separated imidazole moiety in the atoms N2, N3, C25, and C27. The
atomic charge of C25 in the (2E)-IPHC molecule is more positive as
compared with that of the separated imidazole moiety. Mulliken
charge at the N4 (0.279821 e) atom is less negative than at the N5
(0.4771 e) and N6 (0.7571 e) atoms in the (2E)-IPHC molecule
and they exhibited some deviation from those values at the separated
semicarbazide moiety. Atom C31 (0.736084 e) in the (2E)-
IPHC molecule was computed with the most positive charge due to
its attachment to three electronegative atoms, namely two nitrogen
atoms and one oxygen atom. All hydrogen atoms in the (2E)-IPHC
molecule showed positive values and there was not much deviation
in their charge distribution as compared with that in the compositional
groups. Mulliken charges at the carbonyl and amide groups
in the (2E)-IPHC molecule might contribute positively to its biological
activity.