Assignment of Carbon-13 Nuclear Magnetic Resonance Spectra of Some Friedelanes

Article abstract of DOI:10.1002/mrc.1260250202

Carbon-13 resonance assignments of cerin acetate, 2α-pyridine-N-oxyfriedelan-3-one, epi-cerin and its acetate, 3α-hydroxyfriedelan-2-one and its acetate, 3-hydroxyfriedel-3-en-2-one and its acetate, friedelane-3,7-dione, 3β- hydroxyfriedelan-7-one, canophyllol, friedelolactone and friedelolactone-2α-yl acetate, friedelane-2α,3α-diol and its diacetate, friedelane-2β,3α-diyl diacetate, pachysandiyl-A diacetate and friedelane-2β,3β-diyl diacetate have been made.The carbon signals of 3-oxofriedelan-29-ol and its acetate, methyl 3-oxofriedelan-29-oate, 3-oxofriedelan-30-ol, maytenfoliol, maytensifolin-A, maytensifiolin-B, pachysonol and pristimerin reported in the literature have also been considered for their specific resonance assignments.A few signal assignments of some friedelanes, viz. friedelan-28-ol, friedelan-29-ol, friedelan-30-ol, friedelan-29-al, 3-oxofriedelane-21α,26-diol and zeylasterone, reported recently by others, are unusual and have been reviewed.KEY WORDS 13C NMR Friedelanes Revised assignments