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Abietospiran, the Triterpene from the Bark of the White Fir (Abies alba) By Wolfgang Steglich, Manfred Klaar, Lothar Zechlin, and Hans Jiirgen Hecht"' Dedicated to Professor ASfred Treibs on the occasion of his 80th birthday On work-up of fruiting bodies of the fungus Hymeno- chaete mougeotii we recently isolated a triterpene, C3' H4*04, characterized by an IR band (KBr) at 1785 cm - ' ['I. A re-in- vestigation showed that the compound arises from adhering particles of bark of the white fir (A bies alba Mill.) on which it forms a crystalline coating responsible for the silver-gray col- or of the bark. Fig. 1. Molecular structure of abletosplrdn (for the sake of clarity the enantiomer of formula 11) IS shown). The triterpene (I), which we call abietospiran, can be readily obtained in a pure state by extraction of the topmost layer of the bark with light petroleum and recrystallization from ethyl acetate (ca. 0.14 g/g of bark). Its structure was de- termined by single-crystal X-ray structure ana1ysis''l (Fig. 1). (I) is closely related to cyclograndisolide (2) from the bark of Abies grandi~[~'; hence we assign (1) the same absolute configuration. A 9(1 1)-dehydrolanostane derivative was re- cently isolated from needles of the white fir141. Isolation procedure On Soxhlet extraction with light petroleum (40-60 "C, 2 d), a sample of the topmost layer of bark of Abies ~ l b a [ ~ l (34.4 g) afforded 6.3 g of a crude substance, which yielded 4.9 g of (1) on recrystallization from ethyl acetate; m. p. 219-221 "C, [a]:& -16.8" (c=0.68 in CHC13);IR (KBr): 1785 cm-'; 'H- NMR (CDC13):6=0.34,0.47 (AB system, J = 4 Hz, cyclopro- pyl H), 0.86, 0.92, 1.03, 1.17 (each s, C--CH3), 1.01, 1.24 (each d, J= 7 Hz, CH-CH3), 2.84 (br. s, half-width 5 Hz, 3- H), 3.33 (s, OCH3). Received: June 27, 1979 [Z 289 IE] German version: Angew. Chem. 91, 751 (1979) [l] M. Klaar, W. Steglich, Chem. Ber. 110. 1063 (1977). [2] (1) crystallizes in the orthorhombic space group P2,2,2, with a=3006.7(8), b = 712.2(4). c= 1293.4(5) pm, Z=4. 2485 independent reflections were re- corded in the range 2 . 5 ~ 8 ~ 6 5 . 0 " on a STOE single crystal diffractometer with Ni-filtered CuK., radiation; R=3.9% for 2410 reflections with f s 2 m . For details of X-ray structure analysis, see H. J. Hecht el a/.. to be pub- lished. 131 F. H. Allen. J. P. Kutney, J. Trotter. N. D. Weskoft, Tetrahedron Lett. 1971, 283. [4] J.-C. Muller, G. Ourisson, Phytochemistry 13, 1615 (1974). [5] Dead fir tree from Sinzing (nr. Regenshurg, Germany). (I) could also be iso- lated from living fir trees. We thank Prof. Dr. A. Bresinsky for providing the bark. Crystal Structure of Na,NO,[**] By Martin Jansen['l The Raman spectra of Na3N04 and K3N04 were inter- preted assuming the presence of NO:- groups[']; in contrast to Na3N0312t, therefore, those compounds can be regarded as "ortho salts". This is the first deviation from the pronounced tendency of oxoanions of first-row nonmetals to achieve low coordination numbers by forming multiple bonds, in con- trast to their higher homologs. It thus appeared appropriate to confirm the results of vibrational spectroscopy by X-ray structure analysis, especially since no precise information was available about the dimensions of the NO: - ion. Growth of crystals was made difficult by the high reactivi- ty and the thermal sensitivity of Na3N04:addition of fluxes or solvents effected decomposition; temperatures above 500 "C led to attack of the crucible material owing to the ba- sic and oxidizing properties of the orthonitrates. Long-term experiments at a maximum temperature of 415 "C finally proved successful. Several silver crucibles were filled with microcrystalline Na3NO4['I, closed with stoppers, and indi- vidually sealed into glass ampoules under argon. They were placed together in a crucible furnace and heated to 415 "C (heat-up rate 10 "C/h). The changes in degree of crystalliza- tion of the samples were examined by removal of one cruci- ble at a time at intervals of 60 d. After 240 d, a size adaquate for single-crystal studies has been reached (diam. z 0.1 mm); the slowly cooled samples (2.5 "C/h) contained crystals that appear free from defects on examination by optical and X- ray methods. Structural proves the existence of tetrahedral or- thoanions in solid Na3N04. In view of the site symmetry 1, Table 1. Distances [pm] in Na3N04. N O(I) 138.4(3) N O(2) 138.9(3) N O(3) 138.1(3) N O(4) 138.2(3) corn. 139.2 139.3 138.7 138.9 138.4 226.2(3) 225.0(3) 225.7(3) 226.4(3) 227.1(3) 225.8(3) ['I Prof. W. Steglich, Dr. M. Klaar, Dr. L. Zechlin Institut fur Organische Chemie und Biochemie der Universitat Gerhard-Domagk-Strasse 1, D-5300 Bonn (Germany) Dr. H. J. Hecht Forschergruppe Ronrgenstrukturanalyse Biologischer Makromolekiile der Universitat Am Hubland, D-8700 Wiirzburg (Germany) 698 0 Verlag Chemie, GmbH, 6940 Weinheim, 1979 ['I Dr. M. Jansen Institut fur Anorganische und Analytische Chemie der Universitat Heinrich-Buff-Ring 58, D-6300 Giessen (Germany) ["I This work was supported by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie. 0570-0833/79/0909-0698 $ 02.50/0 Angew. Chem. Inl. Ed. Engl. 18 (1979) No. 9

Abietospiran, the Triterpene from the Bark of the White Fir (Abies alba)

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Abietospiran, the Triterpene from the Bark of the White Fir (Abies alba) By Wolfgang Steglich, Manfred Klaar, Lothar Zechlin, and Hans Jiirgen Hecht"' Dedicated to Professor ASfred Treibs on the occasion of his 80th birthday

On work-up of fruiting bodies of the fungus Hymeno- chaete mougeotii we recently isolated a triterpene, C3' H4*04, characterized by an IR band (KBr) at 1785 cm - ' [ ' I . A re-in- vestigation showed that the compound arises from adhering particles of bark of the white fir (A bies alba Mill.) on which it forms a crystalline coating responsible for the silver-gray col- or of the bark.

Fig. 1 . Molecular structure of abletosplrdn (for the sake of clarity the enantiomer of formula 11) I S shown).

The triterpene ( I ) , which we call abietospiran, can be readily obtained in a pure state by extraction of the topmost layer of the bark with light petroleum and recrystallization from ethyl acetate (ca. 0.14 g/g of bark). Its structure was de- termined by single-crystal X-ray structure ana1ysis''l (Fig. 1).

(I) is closely related to cyclograndisolide (2) from the bark of Abies grandi~[~ ' ; hence we assign (1) the same absolute configuration. A 9(1 1)-dehydrolanostane derivative was re- cently isolated from needles of the white fir141.

Isolation procedure

On Soxhlet extraction with light petroleum (40-60 "C, 2 d), a sample of the topmost layer of bark of Abies ~ l b a [ ~ l (34.4 g) afforded 6.3 g of a crude substance, which yielded 4.9 g of (1) on recrystallization from ethyl acetate; m. p. 219-221 "C, [a]:& -16.8" (c=0.68 in CHC13); IR (KBr): 1785 cm-'; 'H- NMR (CDC13): 6=0.34,0.47 (AB system, J = 4 Hz, cyclopro- pyl H), 0.86, 0.92, 1.03, 1.17 (each s, C--CH3), 1.01, 1.24 (each d, J= 7 Hz, CH-CH3), 2.84 (br. s, half-width 5 Hz, 3- H), 3.33 (s, OCH3).

Received: June 27, 1979 [Z 289 IE] German version: Angew. Chem. 91, 751 (1979)

[ l ] M. Klaar, W. Steglich, Chem. Ber. 110. 1063 (1977). [2] (1) crystallizes in the orthorhombic space group P2,2,2, with a=3006.7(8),

b = 712.2(4). c= 1293.4(5) pm, Z=4. 2485 independent reflections were re- corded in the range 2 . 5 ~ 8 ~ 6 5 . 0 " on a STOE single crystal diffractometer with Ni-filtered CuK., radiation; R=3.9% for 2410 reflections with f s 2 m . For details of X-ray structure analysis, see H. J. Hecht el a/.. to be pub- lished.

131 F. H. Allen. J. P. Kutney, J. Trotter. N. D. Weskoft, Tetrahedron Lett. 1971, 283.

[4] J.-C. Muller, G. Ourisson, Phytochemistry 13, 1615 (1974). [ 5 ] Dead fir tree from Sinzing (nr. Regenshurg, Germany). ( I ) could also be iso-

lated from living fir trees. We thank Prof. Dr. A. Bresinsky for providing the bark.

Crystal Structure of Na,NO,[**] By Martin Jansen['l

The Raman spectra of Na3N04 and K3N04 were inter- preted assuming the presence of NO:- groups[']; in contrast to Na3N0312t, therefore, those compounds can be regarded as "ortho salts". This is the first deviation from the pronounced tendency of oxoanions of first-row nonmetals to achieve low coordination numbers by forming multiple bonds, in con- trast to their higher homologs. It thus appeared appropriate to confirm the results of vibrational spectroscopy by X-ray structure analysis, especially since no precise information was available about the dimensions of the NO: - ion.

Growth of crystals was made difficult by the high reactivi- ty and the thermal sensitivity of Na3N04: addition of fluxes or solvents effected decomposition; temperatures above 500 "C led to attack of the crucible material owing to the ba- sic and oxidizing properties of the orthonitrates. Long-term experiments at a maximum temperature of 415 "C finally proved successful. Several silver crucibles were filled with microcrystalline Na3NO4['I, closed with stoppers, and indi- vidually sealed into glass ampoules under argon. They were placed together in a crucible furnace and heated to 415 "C (heat-up rate 10 "C/h). The changes in degree of crystalliza- tion of the samples were examined by removal of one cruci- ble at a time at intervals of 60 d. After 240 d, a size adaquate for single-crystal studies has been reached (diam. z 0.1 mm); the slowly cooled samples (2.5 "C/h) contained crystals that appear free from defects on examination by optical and X- ray methods.

Structural proves the existence of tetrahedral or- thoanions in solid Na3N04. In view of the site symmetry 1,

Table 1. Distances [pm] in Na3N04.

N O(I) 138.4(3) N O(2) 138.9(3) N O(3) 138.1(3) N O(4) 138.2(3)

corn. 139.2 139.3 138.7 138.9

138.4

226.2(3) 225.0(3) 225.7(3) 226.4(3) 227.1 (3) 225.8(3)

['I Prof. W. Steglich, Dr. M. Klaar, Dr. L. Zechlin Institut fur Organische Chemie und Biochemie der Universitat Gerhard-Domagk-Strasse 1, D-5300 Bonn (Germany) Dr. H. J. Hecht Forschergruppe Ronrgenstrukturanalyse Biologischer Makromolekiile der Universitat Am Hubland, D-8700 Wiirzburg (Germany)

698 0 Verlag Chemie, GmbH, 6940 Weinheim, 1979

['I Dr. M. Jansen Institut fur Anorganische und Analytische Chemie der Universitat Heinrich-Buff-Ring 58, D-6300 Giessen (Germany)

["I This work was supported by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie.

0570-0833/79/0909-0698 $ 02.50/0 Angew. Chem. In l . Ed. Engl. 18 (1979) No. 9