JOURSAL OF SATUR.4L
2 98
[VOL.
PRODUCTS
42, so. 3
H. J. KOCHand A. S.PERLIN, Can. J . Chem., 53, 17. R . G. S.RITCHIE,S . CYR,B. KORSCH, 1424 (1975). and C. PEDERSEN, J . Chent. Soc., Perkin 11, 293 (1974). 18. K . B ~ C K 19. K . BOCKand C. PEDERSES, A c t a Chem. Scand., B2g, 2-58 (1975). 20. P. A. J. GORIKand M. MIZUREK,Canadian J . Chem., 53, 1212 (1975). 21. T. REICHSTEIN and E. WEISS, Adoances zn Carbohydrate Chemistry, 17, 65 (1962). 22. C. S. HUDSON and J. hI. JOHSSOS, J . Org. Chem. 37,2748 (1951).
ERRATA
A. Douglas Kinghorn: Characterization of an irritant 4deoxyphorbal diester from Euphorbia tirucalli. T'ol. 42, No. 1, p. 113. R 2 for structure 2 should be -H instead of -OH. The structure should be positioned as follows:
19
CH3
20
Rs
Ra
Z E 2 -COCH= CH-CH=CHCHtCH*C,Hs 1' 2 ' 3' -I1 5' 6' 7' 8
-H
3 -COCH3
-COCHs -COCHs
-H
R4
LY-H
rrH
L. H. Zalkou-, R. S.Harris, 111, and N. I. Burke: The lower terpenoids of Isocoma wriglttii. Vol. 42, S o . 1, pp. 96-102. The correct spelling for the compound represented by structure 2 is modhephene.