Table 1. ¹H NMR Data for Compounds 1 and 2(9) (Siphonochilone)^a.

	1		2
H	δH (ppm)	J (Hz)	δH (ppm)	J (Hz)
2	7.07, s		7.02, br m	137.8
4	2.66, dd	14.2, 10.0	2.68, ddd	15.7, 5.4, 1.6
4′	2.47, m		2.12, dddd	15.7, 18.4, 3.0, 1.4
4a	2.42, m		1.81, ddd	10.8, 10.2, 5.4
5			2.40, dqdd	10.2, 7.1, 2.7, 2.1
6	2.91, dt	13.9, 4.6	6.66, dd	10.1, 2.1
6′	2.13, td	13.9, 4.6
7	2.43, dt	13.9, 4.6	5.91, dd	10.1, 2.7
7′	2.66, m
9	2.81, br d	16.9	2.73 dd	16.7, 1.4
9′	2.58, d	16.9	2.64, br d	16.7
3-Me	1.95, s		1.90, d	1.3
5-Me	1.81, s		1.21, d	7.1
8a-Me	1.15, s		1.02, s
OCOMe	1.96, s

^a1H NMR spectra are included in the SI.