Botrylacton, ein neuer Wirkstoff aus der Nährlösung des Pilzes Botrytis cinerea, 2

Abstract

Botrylacton (1 a), ein Antibioticum aus der Nahrlosung des Pilzes Botrytis cinerea, wurde isoliert und vorwiegend spektroskopisch in der Konstitution aufgeklart. Die Rontgenstrukturanalyse des Acetats ergab die Konfiguration des Tricyclus l a .Botrylactone, a New Antibiotic from the Culture Solution of the Fungus Botrytis Cinereu, 2 l ) Botrylactone (la), an antibiotic, was isolated from the culture solution of the fungus Eotrytis cinerea. Informations about its constitution were taken from mass, 'H, and I3C NMR spectrometry. The absolute configuration was elucidated by X-ray diffraction of the acetate 1 b. To conclude, botrylactone (la) is a tricyclic ring system which may be named as 3,9:4,8-diepoxy-7,9-dihydroxy-2,4,6,8,9-pentamethylpelargono-l,9-iactone.

Botrylactone: new interest in an old molecule—review of its absolute configuration and related compounds

“…Acetylation of it led us to a product whose spectroscopic data were identical to those described for natural acetyl botrylactone whose optical rotation proved to be þ73 (c 2.4 mg, CHCl 3 ), coinciding with the sign described by Welmar et al 9 As a result, it can be inferred that the structure synthesized by Redlich et al should be the enantiomeric to the natural compound, (À)-botrylactone (6). In order to confirm this hypothesis we determined the absolute configuration of natural (þ)-botrylactone using the NMR method.…”

“…Botrylactone is a unique C-9 polyhydroxylated lactone described as a powerful antibiotically active compound reported by Welmar et al 9 Several unsuccessful attempts to isolate this intriguing compound have been made and some of them reported. 10 Recently we isolated it from the B. cinerea cat 2 strain.…”

“…The key NOE correlations were identical to those of 9 indicating that 5 and 9 share the same relative stereochemistry. Therefore, the structure of 2-epihomobotcinolide (5) should be revised to 10 and renamed as botcinin G. Botrylactone was reported for the first time by Welmar et al 9 who initially proposed structure 6a based on spectroscopic data. Although they used the term, 'absolute configuration' in the text of the paper, they did not determine the absolute configuration but its relative configuration by X-ray diffraction of its acetate derivative (6b).…”

“…Although they used the term, 'absolute configuration' in the text of the paper, they did not determine the absolute configuration but its relative configuration by X-ray diffraction of its acetate derivative (6b). 9 Later, Redlich et al synthesized it and revised the originally published structure to 7-OHa-botrylactone (6).…”

“…Welmar et al prepared acetyl botrylactone and reported its optical rotation as þ88 (c 1, CHCl 3 ), 9 while Redlich et al…”