trans-Bicyclo[5.1.0]octane

✍ Scribed by Prof. Dr. W. Kirmse; Dipl.-Chem. Ch. Hase

• Book ID: 101547089
• Publisher: John Wiley and Sons
• Year: 1968
• Tongue: English
• Weight: 273 KB
• Volume: 7
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.196808912

✦ Synopsis

X-ray analysis of the 4-(p-bromobenzoate) ( 2 6 ) leads to the relative configuration of the molecule (Fig. ) (space group P 2 1 , Z = 2 , a = 1 0 . 2 0 A , b = 2 0 . 2 9 A , c = -7 . 9 3 A , $ = 9 0 . 5 2 ' ) . The structure was determined, fully automatically, by finding the position of the bromine atom from Patterson synthesis and subsequent treatment by phase-improvement methods. The pseudoasymmetry due to the position of the bromine could be overcome in that work[****]. This proves the structure (2a) of lumiphorbol triacetate. and shows isophorbol ( l b ) t o be the 4cr-phorbol (4a,9,12$,13,20pentahydroxy-l.6-tigliadien-3-one). Accordingly, lumiphorbol f 2 c ) is a 4a,9,12@,13,20-pentahydroxy-l,7: 2,6-dicyclo-4a-tiglian-3-one or a 7,8@,10,12a-tetrahydroxy-14-(hydroxy-methyI)-l,6,6,9-tetramethylhexacyclo[l0.2.1.02~ 11.03*'4.04r*0. 05~7]pentadecan-l5-one 161.