Pyxinol

Deriv Pyxinol, needles (MeOH-HjO), mp 225-226 °C, [a]j3 + 62.8 (CHCI3, c 0.99), by saponification of diacetylpyxinol with KOH-MeOH StL Pyxine endochrysina Nyl. 

Wilkins AL, Elix JA, Gaul KL, Moberg R (1989a) New hopane triterpenoids from lichens in the family Physciaceae. Aust J Chem 42 1415-1422 Wilkins AL, Elix JA, Gonzalez AG, Perez C (1989b) A one-and two-dimensional and C NMR study of some fernene triterpenoids. Aust J Chem 42 1185-1189 Wilkins AL, Elix JA, Whitton AA (1990) A one- and two-dimensional and C NMR study of some lichen triterpenoids of the pyxinol group. Aust J Chem 43 411-417... 

In addition to diacetylpyxinol (501), Yosioka, Yamauchi, and Kitagawa 345) have identified three new dammarane triterpenoids from Pyxine endochrysina pyxinol (502), 3-0-acetylpyxinol (503) and 12-desoxydiacetylpyxinol (504). 

Most of the 20 odd triterpenes that have been structurally determined are derived from pentacyclic hopane (94). The exceptions are friedelin (95), epifriedelanol, taraxerene, ursolic acid, and diacetyl pyxinol. 

Leucotylic acid (98), phlebic acid A (99), and phlebic acid B (100) are hopane derivatives with a 23-carboxylic acid from Parmelia leucotyliza yl., P. entotheiochroa Hue, and Peltigera aphthosa (L.) Willd. Diacetyl pyxinol (101), known from Pyxine endochrysina yX., possesses adammaran skeleton from X-ray analysis of 3/3, 12/3-di-/ -bromobenzoyl pyxinol. 

Wilkins AL, Elix JA, Whitton AA (1990) A One- and Two-Dimensional H and C-NMR Study of some Lichen Triterpenoids of the Pyxinol Group. Aust J Chem 43 411... 

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