Table 3.

¹³C-¹H and ¹H-¹H coupling constants for monosulfated gymnochrome D (5).

Hydroxypentyl Side Chain		Pentyl Sulfate Side Chain
J-HMBC Correlation	J in Hz a	J-HMBC Correlation	J in Hz a
3 J C3a–H1a′	4	3 J C3b–H1a″	4
3 J C3a–H1b′	5	3 J C3b–H1b″	5
3 J C2–H1a′	8	3 J C5–H1a″	8
3 J C2–H1b′	4	3 J C5–H1b″	4
3 J H2′–H1a′	9.2	3 J H2″–H1a″	9.5
3 J H2′–H1b′	1.9	3 J H2″–H1b″	2.9
3 J C3–H2′		3 J C4–H2″
3 J C3′–H1a′	3	3 J C3″–H1a″	2
3 J C3′–H1b′	2	3 J C3″–H1b″	2
2 J C2′–H1a′	8	2 J C2″–H1a ″	7
2 J C2′–H1b′	3	2 J C2″–H1b″	3

^a Coupling constants are absolute values without sign. The differences in significant digits in the coupling constants are due to the lower measurement accuracies of HMBC-based approaches compared to the extraction from 1D ¹H NMR spectra.