Abstract
The tropolones of western red cedar were collected as the green copper chelates deposited on copper–bronze screen exposed to the vapor from the heated wood in commercial kilns. Decomposition of the chelates with hydrogen sulphide yielded a new tropolone as well as the expected thujaplicins. Its infrared and ultraviolet absorption together with hydrogenation and oxidation reactions established it to be 2,7-dihydroxy-4-isopropyl-2,4,6-cycloheptatrien-1-one. Synthesis was achieved by persulphate oxidation of γ-thujaplicin. The natural substance is identical with the 7-hydroxyhinokitiol obtained by Nozoe from the diazonium salt of 7-amino-hinokitiol and on the basis of color reactions and Rf appears to be the unknown "enol" previously noted by Zavarin and Anderson in paper chromatography of tropolone fractions of western red cedar and incense cedar. The concentration in the wood, determined by quantitative paper chromatography, ranged from 0.01 to 0.08%.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
