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A method for isolation of hundreds of milligrams of lolitrem B is reported. Lolitrem E, the most abundant of the minor lolitrems, was isolated from side fractions and its structure determined by mass spectrometry and one-and two-dimensional NMR techniques. Lolitrem E differs from lolitrem B in being an ether, rather than an acetal, derivative of lolitriol. Evidence is presented that the compound previously isolated by Gallagher and co-workers, and assigned the structure of lolitrem C, was in fact lolitrem E. Lolitrem E, which is not tremorgenic in mice, is proposed as a biosynthetic precursor of lolitrem B.

Crystals isolated from the bile of sheep affected by hepatogenous photosensitization after grazing Panicum dichotomiflorum or Panicum schinzii were soluble in acetic acid but essentially insoluble in common organic solvents. The main component of the crystals was identified by acidic and enzymatic hydrolysis, GC-MS, LSIMS, TLC, and 13C NMR spectroscopy, and X-ray analysis as the calcium salt of epismilagenin /S-D-glucuronide. The 13C NMR spectrum was fully assigned, and the structure confirmed by comparison with model compounds (17-oxoetiocholan-3a-ol glucuronide and epismilagenin). Only saponins derived from diosgenin were detected in the foliage of P. dichotomiflorum and P. schinzii. A metabolic pathway for conversion of P. dichotomiflorum and P. schinzii saponins into the major bile crystal component is proposed.

Crystalloid material soluble in acetic acid was isolated from the bile of lambs with alveld (a hepatogenous photosensitization disease which develops after grazing Narthecium ossifragum). The main components of these bile extracts were shown by hydrolysis, GC-MS, TLC, LSIMS, and 13C NMR, and X-ray analysis to be salts of a 4:1 mixture of episarsasapogenin /3-D-glucuronide (1) and epismilagenin /3-Dglucuronide (2). The 13C NMR spectrum of 1 was fully assigned by comparison with the NMR spectra of model compounds. A metabolic route for conversion of the sarsasapogenin saponins oiN. ossifragum into 1 is proposed. Saponins were extracted from the foliage of N. ossifragum, Tribulus terrestris, and Panicum miliaceum. The saponins were hydrolyzed to sapogenins, which were examined by NMR spectroscopy and GC-MS. P. miliaceum afforded a 4:1 mixture of diosgenin and yamogenin, T. terrestris gave a 5:1 mixture of diosgenin and tigogenin, and N. ossifragum yielded a mixture (82:9:5:4) of sarsasapogenin, smilagenin, yamogenin, and another spirostanol, tentatively identified as neotigogenin.

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