Structural, Vibrational, and Electronic Properties of the Glucoalkaloid Strictosidine: A Combined Experimental and Theoretical Study

Table 5

Experimental and calculated wavenumbers (cm⁻¹) and assignments for strictosidine.

IR solid		B3LYP 6-31G(d)				Assignment (PED > 5%)
Exp.	IR intensity	Monomer		Dimer
		Calculated	IR intensity	Calculated	IR intensity
		3767	30	3633	62	Stre. OH (96%)
		3732	30	3602	6	Stre. OH (95%)
3430	42	3731	49	3556	225	Stre. OH (96%)
3411	44	3724	44	3535	64	Stre. OH (97%)
3390	43	3656	44	3493	47	Stre. N1-H1 (88%) + tors. H1-N1-C2-C13 (11%)
3382	58	3488	0.27	3475	2.49	Stre. N4-H4 (88%) + bend H4-N4-C5 (11%)
3320	51	3260	4	3260	5	Stre. C18-H18 (70%) + stre. C19-H19 (26%)
3211	20	3246	3	3239	12	Stre. C17-H17 (99%)
		3205	38	3183	22	Stre. C9-H9 (36%) + stre. C10-H10 (39%) + stre. C12-H12 (10%)
3180	17	3193	39	3190	28	Stre. C9-H9 (21%) + stre. C10-H10 (16%) + stre. C11-H11 (30%) + C12-H12 (23%)
3152	9	3183	3	3173	2	Stre. C9-H9 (12%) + stre. C10-H10 (24%) + stre. C11-H11 (32%) + stre. C12-H12 (13%)
3150	25	3176	19	3139	1	Stre. sim. C23-H23 (22%) + stre. sim. C23-H23 (19%) + stre. ass. C23-H23 (24%) + stre. C23-H23 (19%)
3140	22	3176	2	3152	14	Stre. C9-H9 (12%) + stre. C10-H10 (17%) + stre. C11-H11 (43%)
		3175	14	3140	7	Stre. C19-C18 (41%) + stre. sim. C18-H18 (25%) + stre. C19-H19 (18%)
3129	12	3161	2	3125	17	Stre. C9-H19 (66%) + stre. sim. C18-H18 (26%)
3105	10	3144	23	3122	7	Stre. C23-H23 ass. (92%)
3100	11	3103	35	3104	20	Stre. C6′-H6′ (91%)
		3102	35	3082	8	Stre. C5-H5 (47%) + stre. C14-H14 (33%)
		3093	25	3075	28	Stre. C14-H14 (74%)
		3076	10	3072	27	Stre. C15-H15 (85%) + stre. C3-H3 (11%)
		3071	44	3069	28	Stre. sim. C23-H23 (72%)
		3070	2	3063	44	Stre. C3-H3 (57%) + stre. C15-H15 (12%)
		3061	42.72	3061	1	Stre. C5-H5 (86%)
		3060	44	3052	54	Stre. C21-H21 (60%)
		3052	6	3050	48	Stre. C14-H14 (65%)
		3041	19	3042	14	Stre. ass. C6-H6 (77%)
		3040	110	3033	13	Stre. C1′-H1′ (77%)
3020	15	3032	13	3032	28	Stre. C4′-H4′ (62%)
		3017	6	3011	37	Stre. C20-H20 (94%)
		3016	2	3008	5	Stre. C2-H2 (44%) + stre. C5-H5 (46%)
		3013	12	3007	3	Stre. C2′-H2′ (31%) + stre. C4′-H4′ (20%) + stre. C5′-H5′ (35%)
2931	26	2999	50	2997	4	Stre. C6-H6 ass. (71%)
2929	23	2989	1	2992	8	Stre. C3′-H3′ (63%) + stre. C6′-H6′ sim. (18%)
2920	12	2985	44	2988	46	Stre. C6′-H6′ (72%)
1690	62	1767	321	1716	308	Stre. C22=O2 (73%)
1628	41	1694	263	1691	272	Stre. C16=C17 (65%) + bend H17-C17-O3 (12%)
1586	7	1619	2	1591	1.5	Stre. (entire indole portion) (33%)
1527	5	1537	3.5	1519	3.6	Stre. C9=C10 (12%) + bend H10-C10 (20%) + bend H1-N1 (11%)
		1531	1.2	1497	4	Bend (scissoring) H6′-C6′ (80%)
		1527	9	1496	7	Bend (scissoring) C23-H23 (63%)
1400	20	1418	32	1415	11	Stre. C15-C16 (16%) + bend H17-C17-O3 (27%)
1399	25	1413	4	1413	4	Bend H-C entire indole portion
1377		1399	6	1395	9	Bend H21-C21 (14%) + bend H5′-C5′ (13%) + tors. H5′-C5′-O5-C1′ (10%) + tors. H4′-C4′-OH (16%)
1365	12	1386	3	1375	8	Tors. H14-C14-C3-N4 (11%) + tors. H15-C15-C14-C3 (11%) + H5-C5-N4-C3 (10%)
1360	10	1381	4	1363	1	Bend H1′-C1′ (16%) + bend H4′-C4′ (15%) + tors. C5′-H5′ (19%)
1350	11	1378	32	1362	19	Bend H3′-C3′ (11%) + bend H21-C21 (16%) + bend H1′-C1′ (14%)
1344	18	1367	47	1345	19	Bend H18-C18-C19 (32%) + bend H2′-C2′ (12%)
1328	13	1348	59	1340	52	Bend H17-C17-O3 (15%) + bend H15-C15 (10%)
		1345	66	1346	29	Bend H17-C17 (12%) + tors. H15-C15-C14-C20 (10%)
1303	30	1342	53	1342	41	Bend H1′-C1′ (22%) + tors. H5′-C5′-O5-C1′ (25%)
		1338	65	1327	9	Bend H20-C20 (15%)
1300	33	1326	22	1320	31	Stre. C13-N1-C2 (29%)
1297	25	1312	7	1301	18	Bend H20-C20 (16%) + bend H3-C3 (10%) + tors. H14-C14-C3-N4 (16%)
1250	22	1267	23	1260	17	Bend H-C entire structure
		1257	40	1243	40	Bend O-H (5′) (18%) + bend H4′-C4′ (10%)
1211	13	1253	117	1252	16	Stre. C17-O3 (22%) + H15-C15 (13%)
		1157	137	1132	41	Stre. O-C2′ (12%) + stre. O-C3′ (22%) + stre. O4-C21 (13%)
		1136	191	1136	26	Stre. C2′-O (28%) + stre. C3′-O (19%)
		1130	63	1130	42	Stre. O1-C23 (18%) + O3-C1′ (18%)
		1128	225	1128	152	Stre. C5′-C6′ (12%) + stre. O1-C23 (13%)
		1123	13	1121	67	Stre. C5′-C4′ (20%) + tors. H6-C6-C5-N4 (15%)
		1118	43	1119	53	Stre. C5′-C4′ (50%)
		1109	112	1190	120	Stre. O-C6′ (17%)
		1102	138	1103	18	Stre. O-C6′ (37%)
1073	30	1100	33	1100	66	Stre. C15-C16 (13%)
1069	38	1090	21	1067	294	Stre. O-C4′ (13%)
1060	40	1079	55	1079	99	Stre. O-C6′ (27%)
		1070	230	1046	51	Stre. O5-C1′ (10%)
		1058	33	1042	88	Tors. H19-C19-C18-C20 (53%)
		1046	10	1036	77	Bend H19-C19-C18 (13%)
		1041	12	1030	196	Stre. C10-C11 (15%)
1028	30	1035	33	1027	16	Bend (rocking) H18-C18 (11%)
1020		1028	176	1025	53	Stre. C1′-O5 (32%) + stre. C2′-C3′ (10%) + stre. C5′-C6′ (11%)
		989	14	978	23	Stre. C5-C6 (30%)
960	12	988	5	972	14	Stre. sim. C22-O1-C23 (27%)
		896	29	883	93	Stre. O5-C5′ (13%) + tors. H6′-C6′-C5′-C4′ (18%)
891	7	894	10	893	11	Bend H4-N4 (22%)
		867	10	868	11	Bend H4-N4 (12%)
		856	0.6	856	0.7	Tors. H-C (entire aromatic ring) (59%)
		844	32	843	16	Stre. C3-C14 (13%) + stre. C15-C16 (11%) + tors. H4-N4-C5-C6 (11%)
763	10	764	30	764	4	Out O1-C22-O2-C16 (63%)
720	11	755	38	754	62	Tors. sim. H-C-C (entire aromatic ring) (40%)
700	11	746	14	739	33	Tors. entire indole portion
		619	9	617	5	Tors. entire structure
607	12	606	1.5	606	3	Bend C17-O3-C21 (15%)
		603	12	601	2	Tors. entire structure

The calculated wavenumbers values in the table are unscaled.