Table 3. Comparison of Experimental and Predicted (Calculated) NMR Chemical Shifts for 1^a,b.

			1′S,2′R,3′S,4′S,5′R,1S,3R,6S,7R,10S,11S,14S—1				1′S,2′R,3′S,4′S,5′R,1R,3S,6R,7S,10R,11R,14R—1
position	δC expt	δH expt	δC calc	ΔδC	δH calc	ΔδH	δC calc	ΔδC	δH calc	ΔδH
1	13.9	0.69	15.8	1.9	0.51	–0.18	15.9	2.0	0.44	–0.25
2a	29.8	0.85	28.2	–1.6	0.99	0.14	32.5	2.7	1.16	0.31
2b		2.16			1.97	–0.19			1.84	–0.32
3	72.5		75.8	3.3			75.8	3.3
4a	33.9	0.77	34.1	0.2	0.90	0.13	31.0	–2.9	0.81	0.04
4b		1.35			1.33	–0.02			1.40	0.05
5a	21.3	1.15	21.7	0.4	1.32	0.17	22.3	1.0	1.25	0.10
5b		1.96			1.90	–0.06			2.06	0.10
6	24.2		26.0	1.8			26.2	2.0
7	35	1.35	36.8	1.8	1.26	–0.09	35.6	0.6	1.27	–0.08
8a	26.8	0.75	26.5	–0.3	0.82	0.07	27.0	0.2	0.81	0.06
8b		1.16			1.15	–0.01			1.19	0.03
9a	39.2	0.91	38.7	–0.5	0.91	0.00	38.6	–0.6	0.84	–0.07
9b		1.47			1.42	–0.05			1.48	0.01
10	41.6		44.5	2.9			45.3	3.7
11	36.2		38.5	2.3			37.0	0.8
12a	25.1	1.27	25.5	0.4	1.21	–0.06	25.4	0.3	1.26	–0.01
12b		1.27			1.34	0.07			1.29	0.02
13a	27.9	1.19	30.2	2.3	1.27	0.08	27.6	–0.3	1.32	0.13
13b		1.73			1.73	0.00			1.58	–0.15
14	61.4	1.19	62.4	1.0	1.00	–0.19	61.4	0.0	1.04	–0.15
15	28.5	1.56	31.9	3.4	1.45	–0.11	31.0	2.5	1.52	–0.04
16	23.3	0.91	19.5	–3.8	0.93	0.02	20.4	–2.9	0.92	0.01
17	23	0.87	21.6	–1.4	0.89	0.02	20.9	–2.1	0.84	–0.03
18	19	0.64	15.4	–3.6	0.70	0.06	15.8	–3.2	0.68	0.04
19	19.1	1.02	17.2	–1.9	0.90	–0.12	17.0	–2.1	0.92	–0.10
20	25.8	1	23.3	–2.5	1.00	0.00	23.7	–2.1	1.05	0.05
1′	94.7	4.39	94.0	–0.7	4.30	–0.09	92.9	–1.8	4.31	–0.08
2′	79.3	3.65	78.7	–0.6	3.60	–0.05	78.0	–1.3	3.66	0.01
3′	76.7	3.44	76.6	–0.1	3.37	–0.07	75.8	–0.9	3.44	0.00
4′	70.7	3	69.1	–1.6	3.46	0.46	73.4	2.7	3.28	0.28
5′	76.1	3.13	73.8	–2.3	3.08	–0.05	72.4	–3.7	3.18	0.05
6′a	61.8	3.72	61.2	–0.6	3.67	–0.05	63.8	2.0	3.65	–0.07
6′b		3.37			3.53	0.16			3.46	0.09
rmsec				2.0		0.1		2.1		0.1
DP4+ 1H datad						21.3%				78.7%
DP4+ 13C datad				99.2%				0.8%
DP4+ all datad			97.2%				2.8%

^aδ_C expt, δ_H expt—experimental carbon and proton chemical shifts, δ_C calc, δ_H calc—calculated carbon and proton chemical shifts, Δδ_C—difference between calculated and experimental carbon chemical shifts, Δδ_H—difference between calculated and experimental proton chemical shifts. Bold represents large deviations |Δδ_H| > 0.2, |Δδ_C| > 3.0.

^bδ values were calculated at the B3LYP/6-311++G(2d,2p) level of theory with PCM model using DMSO as solvent.

^cRoot-mean-square error.

^dDP4+ probability.²⁶