proton nuclear magnetic resonance ( 1h-nmr ) spectra at 90 mhz were measured for a number of side chain isomers of phytosterols ( sterols with a c8h17 side chain , and delta 24- , 24-methylene , delta 22- , 24-ethylidene , 24-methly , 24-ethyl , 24-methyl-delta 22- , 24-ethyl delta 22- , and 24-ethyl-delta 22,25 ( 27 ) -sterols ) with or without a lanthanide shift reagent , tris [ 1,1,1,2,2,3,3 - heptafluoro - 7,7 - dimethyloctane - 4,6 - dionato ] ytterbium , yb ( fod ) 3 , and the effect of yb ( fod ) 3 on the side chain methyl protons is discussed .
C0031866
phytosterols
C0038323
sterols