
%0 Journal Article
%A Wilkins, AL 
%A Elix, JA 
%A Whitton, AA 
%T A One- and Two-Dimensional <sup>1</sup>H and <sup>13</sup>C N.M.R. Study of Some Lichen Triterpenoids of the Pyxinol Group
%J Australian Journal of Chemistry
%D 1990/02/01
%V 43
%N 2
%P 411-417
%K 
%R https://doi.org/10.1071/CH9900411
%U https://www.publish.csiro.au/paper/CH9900411 
%X A complete assignment of the 13C and 1H n.m.r. resonances of the lichen triterpenoids, pyxinol, 3,25-di-O-acetylpyxinol and 3,12,25-tri-O-acetylpyxinol has been achieved by using a combination of one- and two-dimensional n.m.r. data and T1 values. Hydrogen bonding between the 12&#946;- hydroxy group and the carbonyl oxygen of the 25-acetoxy group of 3,25- di-O-acetylpyxinol leads to the furan ring system adopting a  conformation different from that adopted by 25-hydroxy analogues, hence differing chemical shifts are observed for some of the carbons of rings C and D and the furan ring. 
