A Chemical Study of Burley Tobacco Flavour (Nicotiana tabacum L.). IV. Identification of seven new solanone metabolites including 7,8-dioxabicyclo[3.2.1.]octane- and 4,9-dioxabicyclo[3.3.1]nonane derivatives. Preliminary Communication

✍ Scribed by E. Demole; (Mrs) C. Demole; D. Berthet

• Publisher: John Wiley and Sons
• Year: 1974
• Tongue: German
• Weight: 184 KB
• Volume: 57
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.19740570120

✦ Synopsis

The principal axes of the 50%-thermal vibration ellipsoids for C-and 0-atoms vary between 0.18 and 0.35 8. A qualitative impression of the relative orientation of the ellipsoids can be obtained from the stereoscopic drawing of the molecule in Fig. 2 ) , which also shows the overall conformation of the steroid. The A-ring has a, 'twist'conformation with an approximate twofold-axis through the middle of the 4,5-double bond and C(l)-C(Z). The B-ring has a chair conformation slightly distorted due to the sp2-character of C(5) ; the C-ring is an almost undistorted chair conformation, with torsion angles slightly less than the ideal 60", ( I t 1 ) = 56", and the five-membered D-ring is in an envelope conformation with C(13) as flap (for torsion angles see Fig. ). The 8-acetyl substituent at C(17) has the keto group almost syn-planar with C(16)-C( ), which brings O(23) to a distance of about 2.4 A from the #I-hydrogen on C(16).

A calculation of all intra-and intermolecular distances revealed no abnormally close contacts. A packing diagram is shown in Fig. .