Latin American Applied Research 44:137-140 (2014) STUDY ON STRUCTURE-ACTIVITY RELATIONSHIP OF 2E-3- PHENYL PROPENYL ACYLOXY ALKYL PHOSPHONATE MOLECULAR DERIVATIVES H.-M. BI†, P.-T. XIE†, J.-P. HU†, Y. LIU†, F.-Y. YOU† and L.-P. MENG‡ † Handan key laboratory of organic small molecule materials, Handan College, Hebei Handan 056002, China. [email protected] ‡ Hebei Normal University, Shijiazhuang, Hebei Province 050091, China Abstract— The quantum chemistry calculation of obtained. Harmonic vibrational frequencies calculated at 2E-3-phenyl propenyl acyloxy alkyl phosphonate the same level were used for the characterization of sta- derivates was carried out to investigate the relation- tionary points as a minimum. All quantum calculations ship between the structure and plant regulator activ- were performed with the Gaussian 03 program. The ity of these compounds. All the compounds were logP, V, M, Sg and Rm were calculated by Hyperchem studied by HF method with 6-31G* basis set using using the optimized configuration from the result of the PCM model within the self-consistent reaction Gaussian 03. field method to assess solvent effects, and then we es- tablished mathematical correlation between the B. Results and discussions properties and bioactivity of these compounds. The Stability configurations and natural charge result showed that the bioactivity of these com- Figure 1 depicts the structure of compounds. The atom- pounds has a linear relationship with the frontier ic natural charges of compounds are given in Table 1. orbital energy and other properties. At the same These data show that the negative charge is mainly con- time, the active sites of these molecules were predict- centrated in the C (8), and O (10) of carbonyl, These at- ed. These compounds are electron acceptors. oms make the electronegative area of the compound and they could combine with positive area of receptor. The Keywords phosphonate derivatives; quantum positive charge is mainly concentrated in the C (9) of chemistry; quantitative structure-activity relation- carbonyl , P, and N of R in the compound. These atoms ships; solvent effects. are the positive area of the molecule, and they could I. INTRODUCTION combine with negative area of receptor. Phosphonate derivatives are important insecticides (Bai- The energy, main composition and proportion of the riki et al., 2012; Heinze et al., 2012; Chang et al., frontier molecules orbital 2011), have a wide activity about herbicidal sterilization According to the theory of molecular orbital (MO), the and plant growth regulating and so on (Shaekhov et al., highest occupied molecular orbital (HOMO) and the 2011; He, 2003). Wang Tao synthesized 2E-3-phenyl lowest unoccupied molecular orbital (LUMO) have the propenyl acyloxy alkyl phosphonate molecular deriva- greatest influence on the activity of compounds. The re- tives (Wang et al., 2011; He and Liu, 2001) and deter- action between active molecule and macromolecular re- mined the biological activity of these compounds. The ceptor operated on the frontier molecules orbital. EHOMO results showed that these compounds have good plant is the energy of HOMO, which relates to the molecular regulating activity to the plant root cells under certain electron donor abilities. ELUMO is the energy of LUMO, conditions. which relates to the molecular ability of electron ac- A theoretical study of 2E-3-phenyl propenyl acyloxy ceptance. For pesticide molecules, too low-ELUMO or too alkyl phosphonate derivatives was carried out. The high-EHOMO means that the intrinsic molecular activity study found a correlation between the antibacterial ac- is too strong and it is easy to be metabolized in organ- tivity of these compounds (Bittner et al., 2009; Gacitúa ism, The effect of pesticides is difficult to control, so the et al., 2009) and structural parameters. The main factors ELUMO or EHOMO of a pesticide molecule should be suit- affecting the biological activity were analyzed, the in- able to estimate an expected activity value (Wei et al., fluence in biological activity from the changes in the 2009; Yang et al., 1998). molecular structure was explained and the mechanism H 3C H 2C R and sites of action of compounds were discussed. O 3 2 P CH 9 8 7 4 1 O 12 O C H C H C II. METHODS 11 H 3C H 2C O 5 6 A. Method of Calculations 10 All the compounds were studied by HF method with 6- R=(4a) H; (4b)CH3; (4c)CH3CH2; (4d)CH3CH2CH2; 31G* basis set using the PCM model within the self- (4e)(CH3)2CH; (4f)Ph; (4g)4-CH3Ph; (4h)4-ClPh; consistent reaction field method to assess solvent ef- (4i)2-ClPh; (4j)2, 4-Cl2Ph; (4k)4-CH3OPh; fects. For these molecules, the solvation free energies (4l)3-NO2Ph; (4m)2-Furyl; Figure 1. The structure of compounds (ΔGsol) in water and the dipole moments in water were 137 Latin American Applied Research 44:137-140 (2014) Table 1-The atomic natural charge of compounds Compd. P C(1) C(2) C(3) C(4) C(5) C(6) C(7) C(8) C(9) O(10) R 4a 1.516 -0.206 -0.228 -0.188 -0.107 -0.187 -0.230 -0.072 -0.412 0.983 -0.706 — 4b 1.510 -0.211 -0.227 -0.193 -0.099 -0.192 -0.228 -0.092 -0.384 0.988 -0.702 — 4c 1.514 -0.211 -0.227 -0.193 -0.099 -0.192 -0.228 -0.092 -0.383 0.989 -0.702 — 4d 1.512 -0.210 -0.227 -0.191 -0.100 -0.191 -0.228 -0.092 -0.391 0.986 -0.708 — 4e 1.515 -0.210 -0.228 -0.191 -0.100 -0.191 -0.228 -0.092 -0.397 0.983 -0.700 — 4f 1.518 -0.216 -0.227 -0.197 -0.093 -0.197 -0.227 -0.109 -0.366 0.987 -0.706 — 4g 1.518 -0.216 -0.227 -0.197 -0.092 -0.197 -0.228 -0.110 -0.365 0.987 -0.707 — 4h 1.520 -0.214 -0.226 -0.196 -0.095 -0.196 -0.227 -0.104 -0.371 0.986 -0.702 — 4i 1.526 -0.212 -0.228 -0.193 -0.098 -0.193 -0.228 -0.095 -0.377 0.987 -0.696 — 4j 1.528 -0.210 -0.227 -0.191 -0.100 -0.192 -0.229 -0.090 -0.382 0.986 -0.692 — 4k 1.517 -0.216 -0.227 -0.197 -0.092 -0.197 -0.227 -0.110 -0.365 0.988 -0.707 — 4l 1.518 -0.212 -0.226 -0.195 -0.097 -0.194 -0.227 -0.098 -0.377 0.986 -0.696 N 0.666 C(1)0.301; 4m 1.539 -0.207 -0.228 -0.188 -0.105 -0.188 -0.230 -0.079 -0.408 0.984 -0.693 C(2)-0.326 Table 2. The energy of the molecular frontier orbitals (eV) Compd EHOMO ELUMO ΔE Compd EHOMO ELUMO ΔE 4a -8.70554 1.887669 10.5932 4h -8.51778 2.174751 10.69253 4b -8.60322 2.093116 10.69634 4i -8.52621 2.082232 10.60844 4c -8.60131 2.093933 10.69525 4j -8.58608 1.989712 10.57579 4d -8.60921 2.040326 10.64953 4k -8.40757 2.284686 10.69225 4e -8.61274 2.032162 10.64491 4l -8.6073 1.423439 10.03074 4f -8.44594 2.271624 10.71756 4m -8.45737 1.92767 10.38504 4g -8.42607 2.278699 10.70477 Table 3. The main composition and proportion of molecular frontiers orbital Compd R HOMO LUMO C(1)20.39; C(2)3.73; C(3)7.25; C(4)22.02; C(1)14.93; C(3)9.44; C(4)7.81; C(5)6.00; 4a H C(5)7.46; C(6)4.74; C(7)5.92; C(8)23.17; C(6)3.08; C(7)22.51; C(8)17.97; C(9)5.79; O(10)4.85 O(10)5.64; C(1)19.89; C(2)3.61; C(3)7.29; C(4)21.06; C(1)15.52; C(3)9.70; C(4)9.45; C(5)6.03; 4b CH3 C(5)7.61; C(6)4.34; C(7)6.93; C(8)22.52; C(6)3.44; C(7)20.44; C(8)18.12; C(9)5.21; O(10)3.67 O(10)5.17; C(1)19.86; C(2)3.61; C(3)7.29; C(4)21.03; C(1)15.46; C(3)9.67; C(4)9.42; C(5)6.00; 4c CH2CH3 C(5)7.61; C(6)4.34; C(7)6.94; C(8)22.50; C(6)3.44; C(7)20.38; C(8)18.09; C(9)5.18; O(10)3.66 O(10)5.12; C(1)20.08; C(2)3.56; C(3)7.35; C(4)21.36; C(1)14.74; C(3)9.34; C(4)8.57; C(5)5.68; 4d CH2CH2CH3 C(5)7.63; C(6)4.48; C(7)6.96; C(8)22.73; C(6)3.30; C(7)20.32; C(8)17.56; C(9)5.18; O(10)4.40 O(10)5.00; C(1)20.15; C(2)3.55; C(3)7.39; C(4)21.44; C(1)14.82; C(3)9.35; C(4)8.59; C(5)5.76; 4e CH(CH3)2 C(5)7.62; C(6)4.53; C(7)6.94; C(8)22.78; C(6)3.28; C(7)20.66; C(8)17.60; C(9)5.37; O(10)4.54 O(10)5.31; C(1)14.48; C(3)8.87; C(4)9.43; C(5)5.65; C(1)9.32; C(2)3.35; C(3)7.45; C(4)21.21; C(5)7.58; 4f C(6)3.26; C(7)18.38; C(8)16.44; C(9)5.42; C(6)4.08; C(7)8.04; C(8)21.29; O(10)3.99 O(10)5.05; C(1)18.72; C(2)3.20; C(3)7.29; C(4)19.56; C(1)14.60; C(3)8.92; C(4)9.46; C(5)5.63; 4g C H 3 C(5)7.41; C(6)3.94; C(7)8.05; C(8)20.91; C(6)3.31; C(7)18.26; C(8)16.48; C(9)5.38; O(10)4.03 O(10)5.02; C(1)19.61; C(2)3.53; C(3)7.35; C(4)20.66; C(1)13.70; C(3)8.55; C(4)8.71; C(5)5.48; 4h C l C(5)7.58; C(6)4.19; C(7)7.60; C(8)21.29; C(6)3.02; C(7)18.53; C(8)16.12; C(9)5.37; O(10)3.94 O(10)4.98; C l C(1)19.45; C(2)3.37; C(3)7.37; C(4)20.49; C(1)14.52; C(3)8.88; C(4)8.42; C(5)5.73; 4i C(5)7.54; C(6)4.24; C(7)7.38; C(8)22.41; C(6)3.10; C(7)20.37; C(8)17.17; C(9)6.01; O(10)4.10 O(10)5.83; C l C(1)19.65; C(2)3.47; C(3)7.26; C(4)20.85; C(1)13.98; C(3)8.68; C(4)7.80; C(5)5.63; 4j C(5)7.50; C(6)4.36; C(7)7.38; C(8)22.45; C(6)2.90; C(7)20.72; C(8)16.95; C(9)6.02; C l O(10)4.15 O(10)5.86; C(1)13.27; C(2)2.29; C(3)5.27; C(4)13.93; C(1)14.50; C(3)8.87; C(4)9.47; C(5)5.60; 4k O C H 3 C(5)5.36; C(6)2.74; C(7)6.12; C(8)15.15; C(6)3.30; C(7)18.27; C(8)16.46; C(9)5.32; O(10)3.33; R-C 23.85; R-O 5.04 O(10)4.96; N O 2 C(1)20.02; C(2)3.70; C(3)7.32; C(4)21.20; C(7)1.57; C(8)1.35; P 2.01;R-C 52.33; R-N C(5)7.70; C(6)4.30; C(7)7.20; C(8)21.75; 4l 15.77; R-O 21.81 O(10)3.87 C(1)14.41; C(3)9.16; C(4)7.80; C(5)5.86; O C(1)3.29; C(4)3.55; C(8)4.83; C(12)6.59; R-C 4m C(6)3.01; C(7)21.98; C(8)17.75; C(9)5.74; 58.2; P 10.48 O(10)5.66; 138 H.