FT-IR, Laser-Raman, UV-Vis, and NMR Spectroscopic Studies of Antidiabetic Molecule Nateglinide

Table 1

The experimental and computed vibrational wavenumbers and vibrational assignments of nateglinide results.

Assignment (PED%); Molecular formula: C19H27NO3	Exp. freq. (cm^−1)		The computed parameters for Monomer 2
	IR	Raman	Freq.	Scaled freq.	IIR	SRaman
νsO2H3(100)			3748	3613	78.26	226.52
νsN5H6(100)			3639	3508	32.33	56.46
νsC9H10(17) + νsC11H12(44+ νsC13H14(32)	3289	3285	3206	3091	15.57	292.02
νsC13H14(39) + νsC15H16(10)			3195	3079,98	29.04	42.71
νsC15H16(18)			3186	3071	8.57	107.31
νsC13H14(22) + νsC15H16(67)	3063	3063	3176	3062	3.57	57.71
νsC7H8(68) + νsC9H10(23)	3029		3171	3057	7.64	33.74
νsC18H19(64) + νsC18H20(35)		2937	3044	2934	22.81	112.46
νsC43H44(28) + νsC43H45(32) + νsC43H46(28)	2925		3031	2922	36.09	53.34
νsC33H34(93)	2859	2860	2975	2868	16.76	44.91
νsO1C23(86)	1711		1811	1746	279.97	16.72
νsO4C24(83)	1647	1647	1733	1671	224.63	6.75
νsC9C7(12) + νsC15C13(26)		1607	1654	1594	4.06	36.96
νsC11C9(29) + νsC17C7(22) + δC15C13C11(12)	1541		1633	1574	1.19	8.95
νsN5C24(19) + δH6N5C24(50)	1497		1542	1486	257.57	2.00
δH8C7C9(15) + δH10C9C11(18) + δH14C13C11(18) + δH16C15C17(16) + δC13C11C9(10)	1471		1534	1479	10.80	0.38
δH44C43H46(20) + δH46C43H45(15) + δH48C47H50(20) + δH49C47H48(24)		1462	1513	1459	8.37	10.34
δH32C30H31 (29) + δH37C35H36 (31)		1440	1490	1436	0.69	8.01
δH12C11C9 (18) + δH20C18H19 (25)	1424		1487	1433	7.34	4.42
δH44C43H46(13) + δH45C43H44(10) + δH48C47H50(17) + δH49C47H48(15) + δH50C47H49(15)	1388		1430	1379	9.88	0.76
δH34C33H35(11) + δH45C43H44(11) + δH46C43H45(13)	1367		1411	1360	8.04	0.36
νsO2C23(12) + νsO23C21(10) + δH22C21C23(23)	1339	1339	1391	1341	138.92	6.34
νsC9C7(11) + νsC13C11(13) + νsC15C13(12)+ δH8C7C9(16) + δH12C11C9(10) + δH16C15C17(19)		1311	1361	1312	1.08	2.19
δH3O2C23(15) + τH20C18C17C15(24) + τH22C21C23O2(17)	1290		1339	1291	12.17	6.90
δH26C25C38(23)		1268	1314	1267	2.01	1.47
δH3O2C23(13) + δH22C21C23(28)	1243	1243	1276	1230	11.37	6.35
δH22C21C23(10)	1213	1210	1260	1215	35.96	7.82
δH6N5C24(11) + δH19C18C17(17) + τH22C21C23O2(13)	1187	1182	1224	1180	10.33	12.41
νsC15C13(11) + δH8C7C9(17) + δH10C9C11(16) + δH14C13C11(21) + δH16C15C17(17)+	1157	1155	1207	1164	0.71	3.24
νsO2C23(18) + νsN5C21(35)	1113		1131	1090	150.02	7.17
νsC9C7(19) + νsC15C13(16) + δH8C7C9(10) + δH12C11C9(12)	1081	1080	1110	1070	6.74	4.44
νsC27C25(15) + νsC30C27(11) + νsC38C35(11)	1034	1037	1089	1050	1.62	3.31
νsC38C35(20)	1003	1003	1038	1001	2.60	14.97
τH10C9C11C13(16) + τH12C11C9C7(31) + τH14C13C11C9(26) + τH16C15C17C18(10)	962		1001	965	0.10	0.23
τH8C7C9C11(14) + τH10C9C11C13(25) + τH14C13C11C9(18) + τH16C15C17C18(18)		948	981	946	0.53	0.73
νsC47C41(10) + τH49C47C41C33(10)	933		966	931	4.13	6.27
τH16C15C17C18(10)	914	911	942	908	14.03	1.89
τH8C7C9C11(11) + τH12C11C9C7(13) + τH16C15C17C18(10)	884	880	918	885	0.46	3.67
τH8C7C9C11(26) + τH10C9C11C13(23) + τH14C13C11C9(24) + τH16C15C17C18(26)	825		856	825	0.33	0.73
δC13C11C9(23)	794	790	831	801	1.83	3.28
τC17C7C9C11(10)	752	754	766	738	34.94	2.67
τO4C25N5C24(25) + τO1C21O2C23(10)	721	720	757	730	9.88	1.25
νsC21C18(10) + δC13C11C9(10) + τO1C21O2C23(36)	698		733	707	13.36	10.82
τH8C7C9C11(13) + τC13C11C9C7(13) + τC15C13C11C9(19) + τC17C7C9C11(22)	677		709	683	39.63	0.27
δO1C23O2(41)	577	625	655	631	29.30	8.83
δC17C7C9(11)	557		580	559	8.75	2.77
γC41C30C35C33(12)	458	458	472	455	7.50	2.39
δN5C21C18(10)	424		444	428	2.74	0.98
τH8C7C9C11(12) + τC13C11C9C7(19) + τC15C13C11C9(36)		406	414	399	0.11	0.03
δO2C23C21(14)		261	286	276	5.95	0.70
τC38C35C33C30(12)		227	241	232	1.00	0.31

s, symmetric; as, asymmetric; ν, stretching; δ, in-plane bending; τ, torsion; γ, out-of-plane bending; d_s, scissoring and symmetric bending; ρ, rocking; t, twisting; , wagging; I_IR, IR intensity (km/mol); S_Raman, Raman scattering activity; PED, potential energy distribution; W, wavenumber (cm⁻¹); T, transmittance (%). R²=0.9981 for Monomer 1 and R²=0.9980 for Monomer 2 for IR wavenumbers.