ISSN:
1572-8854
Keywords:
Guayule
;
Parthenium
;
triterpenes
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract The crystal and molecular structures of the title compounds have been determined by direct methods, and refined to a finalR of 0.059 forII and 0.046 forIII. Both molecules crystallize in space group P212121. The cell dimensions forII area=10.096(5),b=11.255(3),c=20.300(7) Å;Z=4,D x=1.188 g cm−3, μ(MoKα)=0.70 cm−1, while the cell dimensions forIII area=7.346(1),b=10.470(3),c=30.546(5) Å;Z=4,D x=1.212 g cm−3, μ(MoKα)=0.74 cm−1. The rings of the triterpene skeletons aretrans-cis-trans-cis connected. The conformations of both molecules are discussed. Also the preparation and the spectral data of (17R, 20S)-3,16-dioxo-25-nor-lanostan-24-oic acid (V) and (17R, 20S)-3,16,24-trioxo-25-hydroxy-16,24-seco-lanostan-25-acetate (VI) are given.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01796059
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