Two new diterpenes related to bertyadionol have been isolated and their structure determined. Degradation of bertyadionol to 2R-methylsuccinic acid provided the configuration at C-2 for this compound. The absolute stereochemistry of bertyadionol and its congeners was established by application of INDOR and NOE techniques.
Photochemistry of bertyadionol and related compounds
作者:E.L. Ghisalberti、P.R. Jefferies、R.F. Toia
DOI:10.1016/s0040-4020(01)93610-5
日期:1978.1
in terms of a novel photorearrangement resulting in transannular bond formation. The structure of this photoproduct was elucidated by a combination of chemical and spectroscopic methods. Two relatedcompounds, diterpene B and D, and their acetate derivatives when photolysed underwent E→Z isomerisation of the conjugated double bond and epimerization about one centre of the cyclopropyl moiety.
The construction of the jatrapholane skeleton was accomplished. The key-step of the synthesis is biomimetic transannular C-C bond formation of a lathyrane-type skeleton. (C) 2001 Elsevier Science Ltd. All rights reserved.