Rearranged 5-Lactaranolide Sesquiterpenes

Compounds included in Part 13 are synthetic derivatives, obtained from blennin A (11.26) 105) and lactarorufin A derivative 11.25 104), respectively. 

In the HNMR spectrum of compound 13.2, the C-13 methylene group doublet was shifted up field (5 3.58, 7= 6.5 Hz) in comparison with the non-rearranged lactone 11.44 in its acetyl derivative 13.3 the signal was shifted downfield (5 4.03 ppm), as expected. 

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