1. Hz, 44 (dd, J = 17, 10.8 Hz, 1H), 5.39 (d, J = 17.4 Hz, 1H), 5.33 (d, J = 10.8 Hz, 1H), p.2

2. Hz, 00 (s, 1H), 4.97 (s, 1H), pp.48-54

1. Hz, 14 (dt, J = 15.0, 12.6 Hz, 1H), 1.55 (s, 3H), 1.36 (s, 3H), pp.52-55

1. Hz, 87 (s, 3H), 3.85 (s, 3H), 3, ), 2.95 (s, 3H), pp.83-86

. Mmol, The residue was purified by silica gel column chromatography (petroleum ether / ethyl acetate 90:10) to afford IV-30b (20 mg, 63%)