Table 1.

The correlations between dihedral angles and vicinal coupling constants of compounds 1–3 and related analogues [16].

Compounds	Dihedral Angles	J3′, 4′α (Hz)	Dihedral Angles	J3′, 4′β (Hz)
	(H3′-C3′-C4′-H4′α)		(H3′-C3′-C4′-H4′β)
1 (2′R,3′S)	50.7°	5.3	169.8°	12.8
2 (2′R,3′S)	51.1°	5.4	170.2°	12.7
3 (2′S,3′S)	54.8°	4.7	173.9°	8.3
Epiremisporine B (2′R,3′S)	53.9°	5.9	173.5°	12.5
Epiremisporine B (2′S,3′S)	54.7°	6.4	173.8°	10.1
Epiremisporine B1 (2′R,3′S)	54.2°	6.6	173.8°	11.3
Epiremisporine B1 (2′S,3′S)	56.0°	6.5	175.2°	10.3
Remisporine B (2′S,3′R)	178.8°	12.2	61.0°	4.3