Pyxine

New dammaranes include 25-acetoxy-20(5),24(i )-epoxy-3-oxodammarane (63) and the related alcohol (64) from the lichen Pyxine coccifera and 3/8,20(i )-dihydroxydammar-24-ene (65) and the corresponding ketone (66) from Barbacenia bicolorThe structures of chikusetsusaponins 1 (ginsenoside Rg2) and la have been elucidated." ... [Pg.138]

Two new hopanes, methyl pyxinate (172) and the corresponding acetate (173), occurin the lichen Pyxine endochrysina along with several dammaranes. Full papers have appeared on the structure of leucotylic acid (174) and on the correlation of zeorin (175) with leucotylin (176). On treatment with acid, methyl leucotylate (177) and leucotylin (176) afford methyl isoleucotylate (178) and isoleucotylin (179), respectively. [Pg.227]

C30H52O4, Mr 476.74, needles, mp. 225-226 C, [ajp -b62.8 (CHClj). A dammarane triterpenetriol from the lichen Pyxine endochrysina. [Pg.536]

Yosioka, L, H. Yamauchi, and I. Kitagawa Lichen Triterpenoids V. On the Neutral Triterpenoids of Pyxine endochrysina Nyl. Chem. Pharm. Bull. (Japan) 20, 502 (1972). [Pg.71]

StL Cryptothecia rubrocincta (Ehrenb.) Thor., Pyxine coccifera (Fee) Nyl. [Pg.166]

Deriv 3-Oxo-20(S),24(R)-epoxydammaran-25-ol, needles (MeOH), mp 152-154°C, by saponification of 25-acetoxy-20(S),24(R)-epoxydam-maran-3-one with KOH-MeOH StL Pyxine coccifera (Fee) Nyl. [Pg.362]

Deriv Triacetylpyxinol, needles (MeOH-HjO), mp 180-181 °C, from 3-0-acetylpyxinol with ACjO-NaOAc by heating under reflux for 2h StL Pyxine endochrysina Nyl. [Pg.370]

MeOH-HjO), [a]o + 30.4 (CHCI3, c 1.01), by saponification of diacetyl-12-deoxypyxinol with KOH-MeOH under reflux in 2h StL Pyxine endochrysina Nyl. [Pg.374]

Yosioka I, Matsuda A, Kitagawa I (1966a) Pyxinic acid, a novel lichen triterpene with 3p-hydroxyl function. Tetrahedron Lett 613-616... [Pg.474]

Yosioka I, Yamauchi H, Kitagawa I (1969c) Diacetylpyxinol, a triterpene alcohol from a lichen Pyxine endochrysina Nyl. Tetrahedron Lett 4241-4244... [Pg.474]

In addition to the previously described pyxinic acid (485) 339), Yosioka et al. 345) have isolated methyl pyxinate (486) and methyl 3-0-acetylpyxinate (487) from Pyxine endochrysina. The structure of these esters was verified by direct comparison with the synthetic derivatives obtained from pyxinic acid. [Pg.208]

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). [Pg.211]

More recently Huneck 176) identified two further dammarane triterpenoids from the related species Pyxine coccifera, namely 25-acetoxy-20( S),24(i )-epoxy-3-oxodammarane (505) and 25-acetoxy-3p-hydroxy-20(5),24(i )-epoxy-dammarane (506). [Pg.211]

Yosioka, I., A. Matsuda, and I. Kitagawa Pyxinic Acid, a Novel Lichen Triterpene with 3p-Hydroxyl Function. Tetrahedron Letters 1966, 613. [Pg.234]

Neutral Triterpenoids of Pyxine endochrysina. Chem. Pharm. Bull. (Japan)... [Pg.234]

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. [Pg.515]

In 1965 Chandrasenan et al. (65) proposed structure 514 for pyxiferin, the main pigment from Pyxine coccifera. This substance was subsequently synthesized (see Scheme 159) and found to differ from natural pyxiferin. Later on Huneck (380) identified pyxiferin with chiodectonic acid and proposed structure 515 for this pigment. [Pg.188]

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